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Source apportionment of PM_(2.5)using PMF combined online bulk and single-particle measurements:Contribution of fireworks and biomass burning

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Journal of Environmental Sciences 2024年第2期136卷 325-336页

作者： Yanjing Zhang Wenshuai Li Lei Li Mei Li Zhen zhou Jianzhen Yu Yang zhou Frontier Science Center for Deep Ocean Multispheres and Earth System(FDOMES)and Physical Oceanography Laboratory Ocean University of ChinaQingdaoShandong 266100China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdaoShandong 266100China Institute of Atmospheric Environment Safety and Pollution Control Jinan UniversityGuangdong 510632China Institute of Environment Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Department of Chemistry Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Division of Environment The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

Fireworks(FW)could significantly worsen air quality in short term during *** to similar tracers with biomass burning(BB),the fast and precise qualification of FW and BB is still *** this study,online bulk and single-particle measurements were combined to investigate the contributions of FW and BB to the overall mass concentrations of PM_(2.5)and specific chemical species by positive matrix factorization(PMF)during the Chinese New Year in Hong Kong in February *** combined information,fresh/aged FW(abundant ^(140)K_(2)NO_(3)^(+)and ^(213)K_(3)SO_(4)^(+)formed from ^(113)K_(2)Cl^(+)discharged by fresh FW)can be extracted from the fresh/aged BB sources,in addition to the Second Aerosol,Vehicles+Road Dust,and Sea Salt *** contributions of FW and BB were investigated during three high particle matter episodes influenced by the pollution transported from the Pearl River Delta *** fresh BB/FW contributed 39.2%and 19.6%to PM_(2.5)during the Lunar Chinese New Year ***,the contributions of aged FW/BB enhanced in the last two episodes due to the aging process,evidenced by high contributions from secondary ***,the fresh BB/FW showed more significant contributions to nitrate(35.1%and15.0%,respectively)compared with sulfate(25.1%and 5.9%,respectively)and OC(14.8%and11.1%,respectively)on *** comparison,the aged FW contributed more to sulfate(13.4%).Overall,combining online bulk and single-particle measurement data can combine both instruments’advantages and provide a new perspective for applying source apportionment of aerosols using PMF.

关键词： Source apportionment PMF Online bulk measurements Single particle analysis Fireworks Biomass burning

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Properties and Characteristics of Regolith-Based Materials for Extraterrestrial Construction

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Engineering 2024年第6期37卷 159-181页

作者： Cheng zhou Yuyue Gao Yan zhou Wei She Yusheng Shi Lieyun Ding Changwen Miao National Center of Technology Innovation for Digital Construction Huazhong University of Science and TechnologyWuhan 430074China School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering Southeast UniversityNanjing 214135China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The construction of extraterrestrial bases has become a new goal in the active exploration of deep *** the construction techniques,in situ resource-based construction is one of the most promising because of its good sustainability and acceptable economic cost,triggering the development of various types of extraterrestrial construction materials.A comprehensive survey and comparison of materials from the perspective of performance was conducted to provide suggestions for material selection and *** types of typical construction materials are discussed in terms of their reliability and applicability in extreme extraterrestrial ***,thermal and optical,and radiation-shielding properties are *** influencing factors and optimization methods for these properties are *** the perspective of material properties,the existing challenges lie in the comprehensive,long-term,and real characterization of regolith-based construction ***,the suggested future directions include the application of high-throughput characterization methods,accelerated durability tests,and conducting extraterrestrial experiments.

关键词： Extraterrestrial construction Characterization Mechanical property Thermal property Optical property Radiation-shielding

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A reweighted damped singular spectrum analysis method for robust seismic noise suppression

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Petroleum Science 2024年第3期21卷 1671-1682页

作者： Wei-Lin Huang Yan-Xin zhou Yang zhou Wei-Jie Liu Ji-Dong Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China SINOPEC Geophysical Research Institute Nanjing211103jiangsuChina

(Multichannel)Singular spectrum analysis is considered as one of the most effective methods for seismic incoherent noise *** utilizes the low-rank feature of seismic signal and regards the noise suppression as a low-rank reconstruction ***,in some cases the seismic geophones receive some erratic disturbances and the amplitudes are dramatically larger than other *** presence of this kind of noise,called erratic noise,makes singular spectrum analysis(SSA)reconstruction unstable and has undesirable effects on the final *** robustify the low-rank reconstruction of seismic data by a reweighted damped SSA(RD-SSA)*** incorporates the damped SSA,an improved version of SSA,into a reweighted *** damping operator is used to weaken the artificial disturbance introduced by the low-rank projection of both erratic and random *** central idea of the RD-SSA method is to iteratively approximate the observed data with the quadratic norm for the first iteration and the Tukeys bisquare norm for the rest *** RD-SSA method can suppress seismic incoherent noise and keep the reconstruction process robust to the erratic *** feasibility of RD-SSA is validated via both synthetic and field data examples.

关键词： Singular spectrum analysis Damping operator Seismic erratic noise Seismic signal processing Robust low-rank reconstruction

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Prediction of damage potential in mainshock–aftershock sequences using machine learning algorithms

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 919-938页

作者： zhou zhou Wang Meng Han Miao Yu Xiaohui Lu Dagang School of Civil and Transportation Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Multi-Functional Shaking Tables Laboratory Beijing University of Civil Engineering and ArchitectureBeijing 100044China College of Civil Engineering Tongji UniversityShanghai 200092China College of Civil Engineering and Architecture Guilin University of TechnologyGuilin 541004China School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China

Assessing the potential damage caused by earthquakes is crucial for a community’s emergency *** this study,four machine learning(ML)methods—random forest,extremely randomized trees,AdaBoost(AB),and gradient boosting(GB)—were employed to develop prediction models for the damage potential of the mainshock(DIMS)and mainshock–aftershock sequences(DIMA).Building structures were modeled using eight single-degree-of-freedom(SDOF)systems with different hysteretic rules.A set of 662 recorded mainshock–aftershock(MS-AS)ground motions was selected from the PEER *** intensity measures(IMs)were chosen to represent the characteristics of the mainshock and *** results revealed that the selected ML methods can well predict the structural damage potential of the SDOF systems,except for the AB *** GB model exhibited the best performance,making it the recommended choice for predicting DIMS and DIMA among the four ML ***,the impact of input variables in the prediction was investigated using the shapley additive explanations(SHAP)*** high-correlation variables were sensitive to the structural period(T).At T=1.0 s,the mainshock peak ground velocity(PGVM)and aftershock peak ground displacement(PGDA)significantly influenced the prediction of *** T increased to 5.0 s,the primary high-correlation factor of the mainshock IMs changed from PGVM to the mainshock peak ground displacement(PGDM);however,the highcorrelation variable of the aftershock IMs remained *** high-correlation factors for DIMS showed trends similar to those of ***,a table summarizing the first and second high-correlation variables for predicting DIMS and DIMA were provided,offering a valuable reference for parameter selection in seismic damage prediction for mainshock–aftershock sequences.

关键词： machine learning mainshock-aftershock damage potential prediction the high-correlation variables SDOF systems

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Seasonal increase in nest defense,but not egg rejection,in a cuckoo host

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Avian Research 2024年第1期15卷 50-54页

作者： Bo zhou Wei Liang Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou 571158China Institute of Biological Resources Jiangxi Academy of ScienceNanchang 330096China

The interactions between avian brood parasites and their hosts provide an informative and easy-to-handle system for studying *** brood parasitism reduces the reproductive success of hosts,and thus,hosts have evolved anti-parasitic strategies,such as rejecting parasitic eggs and adopting aggressive nest defense strategies,to avoid the cost brought on by brood *** test whether host anti-parasitic strategies are adjusted with the risk of being parasitized when the breeding seasons of brood parasites and hosts are not synchronous,we conducted a field experiment assessing nest defense and egg recognition behaviors of the Isabelline Shrike(Lanius isabellinus),a host of the Common Cuckoo(Cuculus canorus).In the local area,the host Isabelline Shrike begins to breed in April,whereas the summer migratory Common Cuckoo migrates to the local area in May and begins to lay parasitic *** showed that nest defense behaviors of the Isabelline Shrike increases significantly after cuckoo arrival,showing higher aggressiveness to cuckoo dummies,with no significant difference in attack rates among cuckoo,sparrowhawk and dove dummies,but their egg rejection did not change *** results imply that Isabelline Shrikes may adjust their nest defense behavior,but not egg rejection behavior,with seasonality.

关键词： Aggression Anti-parasite strategy Egg rejection Mismatch cuckoo parasitism Nest defense

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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

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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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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

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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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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

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