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Multiscale spatiotemporal meteorological drought prediction:A deep learning approach

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Advances in Climate Change Research 2024年第2期15卷 211-221页

作者： jia-li ZHANG Xiao-Meng HUANG Yu-Ze SUN Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModellingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China

Reliable monitoring and thorough spatiotemporal prediction of meteorological drought are crucial for early warning and decision-making regarding drought-related *** utilisation of multiscale methods is effective for a comprehensive evaluation of drought occurrence and progression,given the complex nature of meteorological ***,the nonlinear spatiotemporal features of meteorological droughts,influenced by various climatological,physical and environmental factors,pose significant challenges to integrated prediction that considers multiple indicators and time *** address these constraints,we introduce an innovative deep learning framework based on the shifted window transformer,designed for executing spatiotemporal prediction of meteorological drought across multiple *** formulate four prediction indicators using the standardized precipitation index and the standard precipitation evaporation index as core methods for drought definition using the ERA5 reanalysis *** indicators span time scales of approximately 30 d and one ***-term indicators capture more anomalous variations,whereas long-term indicators attain comparatively higher accuracy in predicting future *** focus on the East Asian region,notable for its diverse climate conditions and intricate terrains,to validate the model's efficacy in addressing the complexities of nonlinear spatiotemporal *** model's performance is evaluated from diverse spatiotemporal viewpoints,and practical application values are analysed by representative drought *** results substantiate the effectiveness of our proposed model in providing accurate multiscale predictions and capturing the spatiotemporal evolution characteristics of *** of the four drought indicators accurately delineates specific facets of the meteorological drought ***,three representative drought events,namely flash drought,sustained drought and severe drought,

关键词： Meteorological drought Spatiotemporal prediction Multiscale Swim transformer Deep learning

Characteristics and Preliminary Causes of Tropical Cyclone Remote Precipitation over China

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JOURnaL OF OCEAN UNIVERSITY OF CHIna 2024年第4期23卷 845-858页

作者： jia, li Ren, Fumin Mcbride, John Leonard Cong, Chunhua nanjing Univ Informat Sci & Technol Sch Atmospher Sci Nanjing 210044 Peoples R China Chinese Acad Meteorol Sci State Key Lab Severe Weather Beijing 100081 Peoples R China Univ Melbourne Sch Earth Sci Melbourne Vic 3052 Australia Bur Meteorol Res & Dev Div Melbourne 3052 Australia Shandong Meteorol Bur Jinan 250031 Peoples R China

In this study, the characteristics and preliminary causes of tropical cyclone remote precipitation (TRP) over China during the period from 1979 to 2020 are investigated. Results indicated that approximately 72.42% of tropical cyclones (TCs) in the Western Pacific produce TRP over China. The peak months for TRP are July and August. The four key regions of TRP are the adjacent areas between the Sichuan and Shaanxi Provinces, the northern coast of the Bohai Sea, the coast of the Yellow Sea, and the southern coast area. The typical distance between the station with TRP and the TC center ranges from 1500 to 2500 km. Most of these stations are situated north to 60 degrees west of north of the TC. The south-west water vapor transportation on the west side of the TC is crucial to TRP. TRP has a decreasing trend because of the decrease in the number of TCs that generate TRP. From the perspective of large-scale environmental conditions, a decrease in the integrated horizontal water vapor transport in Mainland China, the weakening of upward motion at approximately 25 degrees-35 degrees N, which is inconducive to convection, and an increase in low-level vertical wind shear, which is unfavorable for the development of TC in areas with high frequencies of TRP-related TCs, are the factors that result in the decreasing trend of TRP.

关键词： tropical cyclone remote precipitation characteristics causes PREDECESSOR RAIN EVENTS STATISTICAL-AnaLYSIS EAST

A study of novel real-time power balance strategy with virtual asynchronous machine control for regional integrated electric-thermal energy systems

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Science China(Technological Sciences) 2024年第7期67卷 2074-2086页

作者： WANG Rui li Ming-jia WANG YiBo SUN QiuYe ZHANG Pinjia College of Information Science and Engineering Northeastern UniversityShenyang 110819China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China

The development of regional integrated electric-thermal energy systems(RIETES) is considered a promising direction for modern energy supply systems. These systems provide a significant potential to enhance the comprehensive utilization and efficient management of energy resources. Therein, the real-time power balance between supply and demand has emerged as one pressing concern for system stability operation. However, current methods focus more on minute-level and hour-level power optimal scheduling methods applied in RIETES. To achieve real-time power balance, this paper proposes one virtual asynchronous machine(VAM) control using heat with large inertia and electricity with fast response speed. First, the coupling timescale model is developed that considers the dynamic response time scales of both electric and thermal energy systems. Second, a real-time power balance strategy based on VAM control can be adopted to the load power variation and enhance the dynamic frequency response. Then, an adaptive inertia control method based on temperature variation is proposed, and the unified expression is further established. In addition, the small-signal stability of the proposed control strategy is validated. Finally, the effectiveness of this control strategy is confirmed through MATLAB/Simulink and HIL(Hardware-in-the-Loop) experiments.

关键词： regional integrated electric-thermal energy systems real-time power balance virtual asynchronous machine adaptive inertia small-signal stability

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Demonstration of safety characteristics and effects on gut microbiota of Lactobacillus gasseri HMV18

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Food Science and Human Wellness 2024年第2期13卷 611-620页

作者： Xianxian jia Miaomiao jia Xiang Gao Xiang li Mengyuan Wang Shengqiang Du Rui Huang Xiaotong li Jun Zhang Shujin li Chunling Ma Yan Zhang Bin Cong Department of Pathogen Biology Institute of basic MedicineHebei Medical UniversityShijiazhuang 050017China Research Unit of Digestive Tract Microecosystem Pharmacology and Toxicology Chinese Academy of Medical SciencesShijiazhuang 050017China Institute of Basic Medicine Hebei Medical UniversityShijiazhuang 050017China College of Forensic Medicine Hebei Key Laboratory of Forensic MedicineCollaborative Innovation Center of Forensic Medical Molecular IdentificationHebei Medical UniversityShijiazhuang 050017China Hebei Food Safety Key Laboratory Hebei Food Inspection and Research InstituteShijiazhuang 050227China

Human normal flora is a source of *** safety characteristics of a specific isolate determine its application in foods or *** food-borne-pathogen antagonist strain Lactobacillus gasseri HMV18 is one of the isolates from normal human *** this work,we assessed the in vitro pH tolerance,bile tolerance,biogenic amine production,mucin utilization,and safety of in vivo administration to mice to evaluate general health,organ-body weight index,organ histopathological change,whether *** HMV18 can colonize in the gut or modulate the gut microbiota after oral *** results suggest that *** HMV18 can tolerate pH 3 for 2 h,3%bile for 3 h,biogenic amine negative,mucin usage negative,does not encode verified toxins,and cause no visible change in mice's *** HMV18 might not colonize in mice's gut,but can significantly affect the structure of gut microbiota.A bibliographical survey suggested that there were as few as 8 opportunistic infection cases from 1984 to 2022 and that the possibility for *** to cause infection is relatively ***,this work provides a basis for the foods or drugs application of *** HMV18 and gives a map of experiments for the safety assessment of probiotics.

关键词： Probiotics Lactobacillus gasseri Safety assessment Gut microbiota

Effect of Sc on Al_(3)Fe phase and mechanical properties of as-cast AA5052 aluminum alloy

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China Foundry 2024年第3期21卷 257-264页

作者： Yang li Qing Yu Feng-feng Chen jia-wen He Hong-mei Yang Meng-nie li Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical *** studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the *** this study,the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%,0.05%,0.2%,and 0.3%*** results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052 alloy through Sc *** ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.

关键词： AA5052 aluminum alloy Al3Fe phase mechanical properties grain boundary

Stress-assisted corrosion mechanism of 3Ni steel by using gradient boosting decision tree machining learning method

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1311-1321页

作者： Xiaojia Yang Jinghuan jia Qing li Renzheng Zhu Jike Yang Zhiyong liu Xuequn Cheng Xiaogang li Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China AECC Key Laboratory of Advanced Corrosion and Protection of Aeronautical Materials AECC Beijing Institute of Aeronautical MaterialsBeijing 100095China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China

Traditional 3Ni weathering steel cannot completely meet the requirements for offshore engineering development,resulting in the design of novel 3Ni steel with the addition of microalloy elements such as Mn or Nb for strength enhancement becoming a *** stress-assisted corrosion behavior of a novel designed high-strength 3Ni steel was investigated in the current study using the corrosion big data *** information on the corrosion process was recorded using the galvanic corrosion current monitoring *** gradi-ent boosting decision tree(GBDT)machine learning method was used to mine the corrosion mechanism,and the importance of the struc-ture factor was *** exposure tests were conducted to verify the calculated results using the GBDT *** indic-ated that the GBDT method can be effectively used to study the influence of structural factors on the corrosion process of 3Ni ***-ferent mechanisms for the addition of Mn and Cu to the stress-assisted corrosion of 3Ni steel suggested that Mn and Cu have no obvious effect on the corrosion rate of non-stressed 3Ni steel during the early stage of *** the corrosion reached a stable state,the in-crease in Mn element content increased the corrosion rate of 3Ni steel,while Cu reduced this *** the presence of stress,the increase in Mn element content and Cu addition can inhibit the corrosion *** corrosion law of outdoor-exposed 3Ni steel is consistent with the law based on corrosion big data technology,verifying the reliability of the big data evaluation method and data prediction model selection.

关键词： weathering steel stress-assisted corrosion gradient boosting decision tree machining learning

Unraveling the complex roles of macrophages in obese adipose tissue:an overview

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Frontiers of Medicine 2024年第2期18卷 205-236页

作者： Chang Peng Jun Chen Rui Wu Haowen jiang jia li Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou310000China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China University of Chinese Academy of Sciences Beijing100049China Department of Prosthodontics Shanghai Engineering Research Center of Advanced Dental Technology and MaterialsShanghai Key Laboratory of Stomatology&Shanghai Research Institute of StomatologyNational Clinical Research Center for Oral DiseasesShanghai Ninth People’s HospitalCollege of StomatologyShanghai Jiao Tong University School of MedicineShanghai200011China

Macrophages,a heterogeneous population of innate immune cells,exhibit remarkable plasticity and play pivotal roles in coordinating immune responses and maintaining tissue homeostasis within the context of metabolic *** activation of inflammatory macrophages in obese adipose tissue leads to detrimental effects,inducing insulin resistance through increased inflammation,impaired thermogenesis,and adipose tissue ***,adipose tissue macrophages also play a beneficial role in maintaining adipose tissue homeostasis by regulating angiogenesis,facilitating the clearance of dead adipocytes,and promoting mitochondrial *** the heterogeneity of macrophages in obese adipose tissue is crucial for unraveling the pathogenesis of obesity and holds significant potential for targeted therapeutic ***,the dual effects and some potential regulatory mechanisms of macrophages in adipose tissue have been elucidated using single-cell *** this review,we present a comprehensive overview of the intricate activation mechanisms and diverse functions of macrophages in adipose tissue during obesity,as well as explore the potential of drug delivery systems targeting macrophages,aiming to enhance the understanding of current regulatory mechanisms that may be potentially targeted for treating obesity or metabolic diseases.

关键词： obesity inflammation adipose tissue macrophages adipose tissue homeostasis

Wireless Power Supply Based on MNG-MNZ Metamaterial for Cardiac Pacemakers

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 103-112页

作者： Weihua Chen Jingtao jia Xiaoheng Yan Yuhang Song jiayi li Faculty of Electrical and Control Engineering Liaoning Technical UniversityNo.188Longwan South StreetXingchengHuludao 125105China CES

To solve the low power transfer efficiency and magnetic field leakage problems of cardiac pacemaker wireless powering, we proposed a wireless power supply system suitable for implanted cardiac pacemaker based on mu-negative(MNG) and mu-nearzero(MNZ) metamaterials. First, a hybrid metamaterial consisted of central MNG unit for magnetic field concentration and surrounding MNZ units for magnetic leakage shielding was established by theoretical calculation. Afterwards, the magnetic field distribution of wireless power supply system with MNG-MNZ metamaterial slab was acquired via finite element simulation and verified to be better than the distribution with conventional MNG slab deployed. Finally, an experimental platform of wireless power supply system was established with which power transfer experiment and system temperature rise experiment were *** and experimental results showed that the power transfer efficiency was improved from 44.44%,19.42%, 8.63% and 6.19% to 55.77%, 62.39%, 20.81%and 14.52% at 9.6 mm, 20 mm, 30 mm and 50 mm,respectively. The maximum SAR acquired by SAR simulation under human body environment was-7.14 dbm and maximum reduction of the magnetic field strength around the receiving coil was 2.82 A/m. The maximum temperature rise during 30min charging test was 3.85℃,and the safety requirements of human bodies were met.

关键词： Cardiac pacemaker MNG metamaterial MNZ metamaterial Wireless power supply system

Effects of two silicone resin coatings on performance of FeSiAl magnetic powder cores

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1279-1288页

作者： jia-qi liu Zheng-qu Zhu Pu Wang Yi-fan li Jing Pang jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Qingdao Yunlu Advanced Materials Technology Co. Ltd.Qingdao266232ShandongChina

Two silicon resins with excellent thermal stability,JH1123 and JH7102,are used as the insulated agents and binders for the gas-atomized FeSiAl powder,and corresponding magnetic powder cores(MPCs)are *** insulation capability and application prospects of the two silicon resins are evaluated by comparing the magnetic properties of the coated powder and *** scanning electron microscopy,energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy results show that uniform insulation layers are both formed on the powder ***1123 has stronger binding ability,and the JH1123-coated powder exhibits severe agglomeration,with d50(average particle size)approximately twice that of the JH7102-coated *** as-prepared MPCs exhibit outstanding soft magnetic ***,the permeability of FeSiAl@JH1123 is up to 74.0,which is 35.5%higher than that of FeSiAl@JH7102 because JH1123 can further improve the density of the *** for FeSiAl@JH7102,it has better direct current bias and lower core loss of 716.9 mW cm^(−3) at 20 mT and 1000 kHz due to its lower coercivity and greater anti-magnetic saturation ability.A comprehensive comparison shows that FeSiAl@JH1123 is suitable for medium and high frequency applications,while FeSiAl@JH7102 is more suitable for high frequency *** indicates that the use of JH1123 and JH7102 silicon resins for binding and insulated coating not only simplifies the preparation process of MPCs,but also enables the controlled production of MPCs for different applications.

关键词： FeSiAl Insulated coating Magnetic powder core Permeability Core loss