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Cloud-Type-Dependent 1DVAR Algorithm for Retrieving Hydrometeors and Precipitation in Tropical Cyclone Nanmadol from GMI Data

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Advances in Atmospheric Sciences 2024年第3期41卷 407-419页

作者： Linjun HAN Fuzhong WENG hao hu Xiuqing hu School of the Environment China University of Geosciences(Wuhan)Wuhan 430074China Chinese Academy of Meteorological Sciences Beijing 100081China CMA Earth System Modeling and Prediction Centre Beijing 100081China Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological Center(National Center for Space Weather)of CMABeijing 100081China

Understanding the structure of tropical cyclone(TC)hydrometeors is crucial for detecting the changes in the distribution and intensity of precipitation.In this study,the GMI brightness temperature and cloud-dependent 1DVAR algorithm were used to retrieve the hydrometeor profiles and surface rain rate of TC Nanmadol(2022).The Advanced Radiative Transfer Modeling System(ARMS)was used to calculate the Jacobian and degrees of freedom(△DOF)of cloud water,rainwater,and graupel for different channels of GMI in convective conditions.The retrieval results were compared with the Dual-frequency Precipitation Radar(DPR),GMI 2A,and IMERG products.It is shown that from all channels of GMI,rain water has the highest△DOF,at 1.72.According to the radiance Jacobian to atmospheric state variables,cloud water emission dominates its scattering.For rain water,the emission of channels 1–4 dominates scattering.Compared with the GMI 2A precipitation product,the 1DVAR precipitation rate has a higher correlation coefficient(0.713)with the IMERG product and can better reflect the location of TC precipitation.Near the TC eyewall,the highest radar echo top indicates strong convection.Near the melting layer where Ka-band attenuation is strong,the double frequency difference of DPR data reflects the location of the melting.The DPR drop size distribution(DSD)product shows that there is a significant increase in particle size below the melting layer in the spiral rain band.Thus,the particle size may be one of the main reasons for the smaller rain water below the melting layer retrieved from 1DVAR.

关键词： cloud-dependent 1DVAR hydrometeor precipitation GMI DPR

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The Conversion of Non-Dispersed Polymers into Low-Potassium Anti-Collapse Drilling Fluids

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Fluid Dynamics & Materials Processing 2024年第2期20卷 325-335页

作者： hao hu Jian Guan Shanfa Tang Jialuo Rong Yuanpeng Cheng School of Petroleum Engineering Yangzte UniversityWuhan430100China hubei Key Laboratory of Oil and Gas Drilling and Production Engineering Yangtze UniversityWuhan430100China School of Petroleum Engineering Yangtze UniversityNational Engineering Research Center for Oil&Gas Drilling and Completion TechnologyWuhan430100China Engineering Technology Research Institute of PetroChina Great Wall Drilling Engineering Co. Ltd.Panjin124000China

Different drillingﬂuid systems are designed according to mineral composition,lithology and wellbore stability of different strata.In the present study,the conversion of a non-dispersed polymer drillingﬂuid into a low potas-sium anti-collapsing drillingﬂuid is investigated.Since the two drillingﬂuids belong to completely different types,the key to this conversion is represented by new inhibitors,dispersants and water-loss agents by which a non-dispersed drillingﬂuid can be turned into a dispersed drillingﬂuid while ensuring wellbore stability and reason-able rheology(carrying sand—inhibiting cuttings dispersion).In particular,the(QYZ-1)inhibitors and(FSJSS-2)dispersants are used.The former can inhibit the hydration expansion capacity of clay,reduce the dynamic shear force and weaken the viscosity;the latter can improve the sealing effect and reduce theﬁltrate loss.The results have shown that after adding a reasonable proportion of these substances(QYZ-1:FSJSS-2)to the non-dispersed polymer drillingﬂuid,while the apparent viscosity,plastic viscosity,structural viscosity andﬂuidity index under-went almost negligible changes,the dynamic plastic ratio increased,and theﬁltration loss decreased signiﬁcantly,thereby indicating good compatibility.According to the tests(conducted in the Leijia area),the density was 1.293 g/cm3,and after standing for 24 h,the SF(static settlement factor)was 0.51.Moreover,theﬁltration loss was reduced to 4.0 mL,the rolling recovery rate reached 96.92%,with excellent plugging and anti-collapse performances.

关键词： Non-dispersed polymer drilling fluid low potassium anti-collapsing drilling fluid drilling fluid conversion drilling fluid reuse filter vector

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Analysis of conductance and interfacial polarisation behaviours of silicone rubber based on frequency domain spectroscopy

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High Voltage 2024年第1期9卷 56-65页

作者： hao hu Zhidong Jia Xilin Wang Ruiyang Guan Weinan Fan Simin Luo Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhenChina Guangzhou Power Supply China Southern Power Grid Company Ltd.GuangzhouChina

Silicone rubber(SR)is widely used for cable insulation and operates in multi-stress coupling conditions.Its dielectric properties and ageing performance are the essential factors affecting cable operation.In this study,the frequency domain spectroscopy of unaged SR and SR aged under various conditions is measured.The dielectric responses before and after ageing are analysed in depth by the conjoint analysis via multiple complex planes(permittivity,conductivity,and modulus).Typical conductivity and interfacial polarisation properties,as well as property changes resulting from thermal and tensile ageing,are examined.Experimental results show that tensile ageing promotes conductance and interfacial polarisation,while thermal ageing shows the opposite effects.Based on the multi-core model and charge carrier hopping transport model,thermal and tensile ageing mechanisms on the conductance and interfacial polarisation behaviours of SR are demonstrated.Both behaviours exhibit positively correlated changing characteristics,suggesting that the two behaviours may originate from a common process.The carrier transport process,promoted by the tensile effect and slightly suppressed by the thermal effect,is the primary factor and considered an important indicator to evaluate the dielectric properties of SR insulation.

关键词： interfacial rubber insulation

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Artificial neural network-based method for discriminating Compton scattering events in high-purity germaniumγ-ray spectrometer

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Nuclear Science and Techniques 2024年第2期35卷 64-84页

作者： Chun-Di Fan Guo-Qiang Zeng hao-Wen Deng Lei Yan Jian Yang Chuan-hao hu Song Qing Yang Hou College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China

To detect radioactive substances with low activity levels,an anticoincidence detector and a high-purity germanium(HPGe)detector are typically used simultaneously to suppress Compton scattering background,thereby resulting in an extremely low detection limit and improving the measurement accuracy.However,the complex and expensive hardware required does not facilitate the application or promotion of this method.Thus,a method is proposed in this study to discriminate the digital waveform of pulse signals output using an HPGe detector,whereby Compton scattering background is suppressed and a low minimum detectable activity(MDA)is achieved without using an expensive and complex anticoincidence detector and device.The electric-field-strength and energy-deposition distributions of the detector are simulated to determine the relationship between pulse shape and energy-deposition location,as well as the characteristics of energy-deposition distributions for fulland partial-energy deposition events.This relationship is used to develop a pulse-shape-discrimination algorithm based on an artificial neural network for pulse-feature identification.To accurately determine the relationship between the deposited energy of gamma(γ)rays in the detector and the deposition location,we extract four shape parameters from the pulse signals output by the detector.Machine learning is used to input the four shape parameters into the detector.Subsequently,the pulse signals are identified and classified to discriminate between partial-and full-energy deposition events.Some partial-energy deposition events are removed to suppress Compton scattering.The proposed method effectively decreases the MDA of an HPGeγ-energy dispersive spectrometer.Test results show that the Compton suppression factors for energy spectra obtained from measurements on ^(152)Eu,^(137)Cs,and ^(60)Co radioactive sources are 1.13(344 keV),1.11(662 keV),and 1.08(1332 keV),respectively,and that the corresponding MDAs are 1.4%,5.3%,and 21.6%lower,respectively.

关键词： High-purity germaniumγ-ray spectrometer Pulse-shape discrimination Compton scattering Artificial neural network Minimum detectable activity

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Scutellarein Ameliorated Chondrocyte Inflammation and Osteoarthritis in Rats

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Current Medical Science 2024年第2期44卷 355-368页

作者： Shao-ze JING Shu-han YANG Yun-kun QU Hai-hu hao hua WU Department of Orthopedics Third Hospital of Shanxi Medical UniversityShanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalTaiyuan 030032China Department of Orthopedics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:Osteoarthritis(OA)is a degenerative joint disorder characterized by the gradual degradation of joint cartilage and local inflammation.This study aimed to investigate the anti-OA effect of scutellarein(SCU),a single-unit flavonoid compound obtained from Scutellaria barbata D.Don,in rats.Methods:The extracted rat chondrocytes were treated with SCU and IL-1β.The chondrocytes were divided into control group,IL-1βgroup,IL-1β+SCU 50µmol/L group,and IL-1β+SCU 100µmol/L group.Morphology of rat chondrocytes was observed by toluidine blue and safranin O staining.CCK-8 method was used to detect the cytotoxicity of SCU.ELISA,qRT-PCR,Western blotting,immunofluorescence,SAβ-gal staining,flow cytometry,and bioinformatics analysis were applied to evaluate the effect of SCU on rat chondrocytes under IL-1βintervention.Additionally,anterior cruciate ligament transection(ACL-T)was used to establish a rat OA model.Histological changes were detected by safranin O/fast green,hematoxylin-eosin(HE)staining,and immunohistochemistry.Results:SCU protected cartilage and exhibited anti-inflammatory effects via multiple mechanisms.Specifically,it could enhance the synthesis of extracellular matrix in cartilage cells and inhibit its degradation.In addition,SCU partially inhibited the nuclear factor kappa-B/mitogen-activated protein kinase(NF-κB/MAPK)pathway,thereby reducing inflammatory cytokine production in the joint cartilage.Furthermore,SCU significantly reduced IL-1β-induced apoptosis and senescence in rat chondrocytes,further highlighting its potential role in OA treatment.In vivo experiments revealed that SCU(at a dose of 50 mg/kg)administered for 2 months could significantly delay the progression of cartilage damage,which was reflected in a lower Osteoarthritis Research Society International(OARSI)score,and reduced expression of matrix metalloproteinase 13(MMP13)in cartilage.Conclusion:SCU is effective in the therapeutic management of OA and could serve as a potential candidate for future clinical drug therapy for OA.

关键词： scutellarein osteoarthritis apoptosis mitogen-activated protein kinase(MAPK) nuclear factor kappa-B(NF-κB)

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Tailoring the microstructure of Mg-Al-Sn-RE alloy via friction stir processing and the impact on its electrochemical discharge behaviour as the anode for Mg-air battery

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Journal of Magnesium and Alloys 2024年第4期12卷 1554-1565页

作者： Jingjing Liu hao hu Tianqi Wu Jinpeng Chen Xusheng Yang Naiguang Wang Zhicong Shi School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006China hunan Institute of Metrology and Test Changsha 410014China Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

Constructing the magnesium alloy with fine grains,low density of dislocations,and weak crystal orientation is of crucial importance to enhance its comprehensive performance as the anode for Mg-air battery.However,this unique microstructure can hardly be achieved with conventional plastic deformation such as rolling or extrusion.Herein,we tailor the microstructure of Mg-Al-Sn-RE alloy by using the friction stir processing,which obviously refines the grains without increasing dislocation density or strengthening crystal orientation.The Mg-air battery with the processed Mg-Al-Sn-RE alloy as the anode exhibits higher discharge voltages and capacities than that employing the untreated anode.Furthermore,the impact of friction stir processing on the electrochemical discharge behaviour of Mg-Al-Sn-RE anode and the corresponding mechanism are also analysed according to microstructure characterization and electrochemical response.

关键词： Magnesium anode Electrochemical discharge behaviour Mg-air battery Friction stir processing

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FusionNN:A Semantic Feature Fusion Model Based on Multimodal for Web Anomaly Detection

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Computers, Materials & Continua 2024年第5期79卷 2991-3006页

作者： Li Wang Mingshan Xia hao hu Jianfang Li Fengyao Hou Gang Chen Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Spallation Neutron Source Science Center(SNSSC) Dongguan523803China School of Nuclear Technology University of Chinese Academy of SciencesBeijing100049Chin

With the rapid development of the mobile communication and the Internet,the previous web anomaly detectionand identificationmodels were built relying on security experts’empirical knowledge and attack features.Althoughthis approach can achieve higher detection performance,it requires huge human labor and resources to maintainthe feature library.In contrast,semantic feature engineering can dynamically discover new semantic featuresand optimize feature selection by automatically analyzing the semantic information contained in the data itself,thus reducing dependence on prior knowledge.However,current semantic features still have the problem ofsemantic expression singularity,as they are extracted from a single semantic mode such as word segmentation,character segmentation,or arbitrary semantic feature extraction.This paper extracts features of web requestsfrom dual semantic granularity,and proposes a semantic feature fusion method to solve the above problems.Themethod first preprocesses web requests,and extracts word-level and character-level semantic features of URLs viaconvolutional neural network(CNN),respectively.By constructing three loss functions to reduce losses betweenfeatures,labels and categories.Experiments on the HTTP CSIC 2010,Malicious URLs and HttpParams datasetsverify the proposedmethod.Results show that compared withmachine learning,deep learningmethods and BERTmodel,the proposed method has better detection performance.And it achieved the best detection rate of 99.16%in the dataset HttpParams.

关键词： Feature fusion web anomaly detection multimodal convolutional neural network(CNN) semantic feature extraction

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Agricultural production structure,market conditions and farmers’nutritional intake in rural China

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Journal of Integrative Agriculture 2022年第6期21卷 1812-1824页

作者： WAN Yue hu hao Wuyang hu College of Economics and Management Nanjing Agricultural UniversityNanjing 210095P.R.China Department of Agricultural Environmentaland Development EconomicsThe Ohio State UniversityColumbus 43210USA

Nutrition poverty alleviation is an effective measure to improve the nutritional status of economically disadvantaged individuals,fundamentally improving their health and reducing poverty.Based on the Entitlement Theory and using the China Health and Nutrition Survey(CHNS)data,this paper examines the relationship between farmers’nutritional intake,production structure and regional market conditions.Results show that farmers with diversified production have better nutritional intake than those who specialize.Furthermore,the correlation between regional market conditions and nutritional intake varies between economically disadvantaged and non-economically disadvantaged households.Market conditions significantly influence the carbohydrate and fat intake of economically disadvantaged households and are positively associated with the dietary structure and nutritional intake of non-economically disadvantaged ones.Moreover,income is positively correlated with the nutritional intake of non-economically disadvantaged households but not with economically disadvantaged ones.

关键词： Chinese farmer nutrition economically disadvantaged households diversity of agricultural production regional market conditions

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4-Nitrocatechol as a novel matrix for low-molecular-weight compounds in situ detection and imaging in biological tissues by MALDI-MSI

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Chinese Chemical Letters 2024年第6期35卷 486-490页

作者： hualei Xu Manman Han Haiqiang Liu Liang Qin Lulu Chen hao hu Ran Wu Chenyu Yang hua Guo Jinrong Li Jinxiang Fu Qichen hao Yijun Zhoub Jinchao Fengb Xiaodong Wang Key Laboratory of Mass Spectrometry Imaging and Metabolomics(Minzu University of China) State Ethnic Affairs CommissionBeijing 100081China College of Life and Environmental Sciences Centre for Imaging&Systems BiologyMinzu University of ChinaBeijing 100081China

Low-molecular-weight(LMW)compounds are ubiquitous in living organisms and play essential roles in biological processes.The direct analysis of LMW compounds in biological tissues by matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI)could provide a more comprehensive understanding of their essential functions.Here,we evaluated 4-nitrocatechol(4-NC)as a novel positive-ion matrix for enhancing in situ detection and imaging of LMW compounds from the rat liver,brain,and germinating Chinese-yew seed by MALDI-MS.Our results showed that the 4-NC possessed remarkable features,including strong ultraviolet absorption,uniform matrix crystal,excellent chemical stability,and fewer matrix-related background peaks.The use of 4-NC led to the successful detection of 232,218,and193 LMW compounds from the three abovementioned tissue sections,respectively.Also,the use of 4-NC improved the imaging quality of LMW compounds in tissue sections through MALDI-MSI and has the potential as a matrix for MALDI tissue imaging of LMW compounds.

关键词： MALDI-MSI 4-Nitrocatechol LMW compounds In situ detection Tissue imaging

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康德自由与自然因果性的相容论论证

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哲学动态 2024年第4期 58-69,128页

作者：胡好湖南师范大学中华伦理文明研究中心、湖南师范大学哲学系

在康德哲学中,自由与自然因果性的相容论面临两难:如果自然因果性成立,自由怎么办;如果自由得以可能,自然因果性又怎么办。前一方面的重点是积极自由的可能性论证。既然知性世界和感官世界截然二分,那么无时间的理知原因是否可能产生时... 详细信息

在康德哲学中,自由与自然因果性的相容论面临两难:如果自然因果性成立,自由怎么办;如果自由得以可能,自然因果性又怎么办。前一方面的重点是积极自由的可能性论证。既然知性世界和感官世界截然二分,那么无时间的理知原因是否可能产生时间中的自然结果?这即是异质性难题。对于解决该难题,相较于以往的取消论和转化论,例示说更具优势,它是指,我们能够设想命令这一例子来体现积极自由,由此证成它的可能性。至于后一方面,很少有人注意到,一旦自由得到拯救,它会反过来威胁自然因果性的连续性和必然性。其中,连续性问题可以通过回溯出与理性因果性一致的自然原因来解决,必然性问题则可以通过自由任意选择不同的自然因果序列来解决。由此,康德相容论面临的两难问题能够得到妥善解决。

关键词：决定论异质性连续性必然性

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