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Improving the Forecasts of Coastal Wind Speeds in Tianjin,China Based on the WRF Model with Machine Learning Algorithms

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Journal of Meteorological Research 2024年第3期38卷 570-585页

作者： Weihang ZHANG Meng TIAN Shangfei hai Fei WANG Xiadong AN Wanju li Xiaodong li lifang SHENG College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao266100China Tianjin Key Laboratory for Oceanic Meteorology Tianjin Institute of Meteorological ScienceTianjin300074China CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing100081China Qingdao Meteorological Bureau Qingdao266003China

Characterized by sudden changes in strength,complex influencing factors,and significant impacts,the wind speed in the circum-Bohai Sea area is relatively challenging to *** the western side of Bohai Bay,as the economic center of the circum-Bohai Sea,Tianjin exhibits a high demand for accurate wind *** this study,three machine learning algorithms were employed and compared as post-processing methods to correct wind speed forecasts by the Weather Research and Forecast(WRF)model for *** results showed that the random forest(RF)achieved better performance in improving the forecasts because it substantially reduced the model bias at a lower computing cost,while the support vector machine(SVM)performed slightly worse(especially for stronger winds),but it required an approximately 15 times longer computing *** back propagation(BP)neural network produced an average forecast significantly closer to the observed forecast but insufficiently reduced the *** regard to wind speed frequency forecasting,the RF method commendably corrected the forecasts of the frequency of moderate(force 3)wind speeds,while the BP method showed a desirable capability for correcting the forecasts of stronger(force>6)*** addition,the 10-m u and v components of wind(u_(10)and v_(10)),2-m relative humidity(RH_(2))and temperature(T_(2)),925-hPa u(u925),sea level pressure(SLP),and 500-hPa temperature(T_(500))were identified as the main factors leading to bias in wind speed forecasting by the WRF model in Tianjin,indicating the importance of local dynamical/thermodynamic processes in regulating the wind *** study demonstrates that the combination of numerical models and machine learning techniques has important implications for refined local wind forecasting.

关键词： machine learning Weather Research and Forecast(WRF)model wind speed forecasting coastal region

Sourcing the merits of 3D integrated air cathodes for highperformance Zn-air batteries by bubble pump consumption chronoamperometry

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Nano Research 2024年第8期17卷 6951-6959页

作者： Mengxuan li linfeng Yu hai liu Chuanyi Zhang Jiazhan li liang Luo Xiaoming Sun State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Zn-air batteries(ZABs)as a potential energy conversion system suffer from low power density(typically≤200 mW·cm^(−2)).Recently,three-dimensional(3D)integrated air cathodes have demonstrated promising performance over traditional twodimensional(2D)plane ones,which is ascribed to enriched active sites and enhanced diffusion,but without experimental ***,we applied a bubble pump consumption chronoamperometry(BPCC)method to quantitatively identify the gas diffusion coefficient(D)and effective catalytic sites density(ρEC)of the integrated air cathodes for ***,the D andρEC values can instruct consequent optimization on the growth of Co embedded N-doped carbon nanotubes(CoNCNTs)on carbon fiber paper(CFP)and aerophilicity tuning,giving 4 times D and 1.3 timesρEC over the conventional 2D Pt/C-CFP *** a result,using the CoNCNTs with half-wave potential of merely 0.78 V ***(Pt/C:0.89 V ***),the superaerophilic CoNCNTs-CFP cathode-based ZABs exhibited a superior peak power density of 245 mW·cm^(−2) over traditional 2D Pt/C-CFP counterparts,breaking the threshold of 200 mW·cm^(−2).This work reveals the intrinsic feature of the 3D integrated air cathodes by yielding exact D andρEC values,and demonstrates the feasibility of BPCC method for the optimization of integrated electrodes,bypassing trial-and-error strategy.

关键词： Zn-air batteries three-dimensional(3D)integrated air cathodes superaerophilic gas diffusion coefficient effective catalytic sites density

Protein succinylation,hepatic metabolism,and liver diseases

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World Journal of Hepatology 2024年第3期16卷 344-352页

作者： Shuang liu Rui li Ya-Wen Sun hai lin hai-Fang li College of Animal Science and Veterinary Medicine Shandong Agricultural UniversityTai’an 271018Shandong ProvinceChina College of life Sciences Shandong Agricultural UniversityTai’an 271018Shandong ProvinceChina

Succinylation is a highly conserved post-translational modication that is processed via enzymatic and non-enzymatic *** exhibits strong effects on protein stability,enzyme activity,and transcriptional *** succinylation is extensively present in the liver,and increasing evidence has demonstrated that succinylation is closely related to hepatic *** instance,histone acetyltransferase 1 promotes liver glycolysis,and the sirtuin 5-induced desuccinylation is involved in the regulation of the hepatic urea cycle and lipid ***,the effects of succinylation on hepatic glucose,amino acid,and lipid metabolism under the action of various enzymes will be discussed in this *** addition,how succinylases regulate the progression of different liver diseases will be reviewed,including the desuccinylation activity of sirtuin 7,which is closely associated with fatty liver disease and hepatitis,and the actions of lysine acetyltransferase 2A and histone acetyltransferase 1 that act as succinyltransferases to regulate the succinylation of target genes that influence the development of hepatocellular *** view of the diversity and significance of protein succinylation,targeting the succinylation pathway may serve as an attractive direction for the treatment of liver diseases.

关键词： Protein succinylation Hepatic metabolism Fatty liver Hepatitis Hepatocellular carcinoma

Microstructure and properties of TP2 copper tube with La microalloying by horizontal continuous casting

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China Foundry 2018年第1期15卷 31-36页

作者： Jin-hu Wu Shi-hong Zhang Yan Chen hai-hong li hong-wu Song Ming Cheng Jin-song liu Institute of Metal Research Chinese Academy of Sciences Shenvang 110016 China University of Chinese Academy of Sciences Beijing 100049. China School of Environment and Materials Engineering Yantai University Yantai 264005 China

The TP2 copper tube was prepared with La microalloying by horizontal continuous casting(HCC). The absorptivity of La and its effects on microstructure, tensile and corrosion properties of HCC TP2 copper tube were studied by means of the inductively coupled plasma optical emission spectrometer(ICP-OES), optical microscope(OM), scanning electron microscope(SEM) and potentiodynamic polarization measurements. The results show that the absorptivity of La in the HCC TP2 copper tube is about 15% under antivacuum conditions due to the good chemical activities of La. The impurity elements in copper tube such as O, S, Pb and Si can be significantly reduced, and the average columnar dendrite spacing of the copper tube can also be reduced from 2.21 mm to 0.93 mm by adding La. The ultimate tensile strength and the elongation with and without La addition are almost unchanged. However, the annual corrosion rate of the HCC TP2 copper tube is reduced from 10.18 mm·a^(-1) to 9.37 mm·a^(-1) by the purification effect of trace La.

关键词： rare earth microstructure mechanical properties corrosion resistance HCC TP2 copper tube

Differential Innervation of Secretory Coils and Ducts in Human Eccrine Sweat Glands

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Chinese Medical Journal 2018年第16期131卷 1964-1968页

作者： Zhan Ouyang hai-hong li Ming-Jun Zhang Si-Tian Xie liu-Hang-Hang Cheng Department of Burn and Plastic Surgery The Second Affiliated Hospital Shantou University Medical College Shantou Guangdong 515041 China

Background： Previous studies demonstrate that eccrine sweat glands are innervated by both cholinergic and adrenergic nerves. However, it is still unknown whether the secretory coils and ducts ofeccrine sweat glands are equally innervated by the sympathetic nerve fibers. To welt understand the mechanisms on sweat secretion and reabsorption, the differential innervation of secretory coils and ducts in human eccrine sweat glands was investigated in the study. Methods： From June 2016 to June 2017, six human skins were fixed, paraffin-embedded, and cut into 5 μm-thick sections, followed by costaining for nerve fiber markers protein gene product 9.5 （PGP 9.5）, tyrosine hydroxylase （TH） and vasoactive intestinal peptide （VIP）, and eccrine sweat gland markers K7, S100P, and K14 by combining standard immunofluorescence with tyramide signal amplification （IF-TSA）. Stained sections were observed under the microscope, photographed, and analyzed. Results： The fluorescent signals of PGP 9.5, TH, and VIP were easily visualized, by 1F-TSA, as circular patterns surrounding eccrine sweat glands, but only PGP 9.5 could be observed by standard IF. The IF-TSA method is more sensitivity than standard IF in detecting antigens expressed at low levels. PGP 9.5, TH, and VIP appeared primarily surrounding the secretory coils and sparsely surrounding the sweat ducts. Conclusion： Sweat secretion is mainly controlled by autonomic nerves whereas sweat reabsorption is less affected by nerve activity.

关键词： Duct Eccrine Sweat Glands Innervation Nerve Fibers Secretory Coil Tyramide Signal Amplification

Computed tomography-based radiomics combined with machine learning allows differentiation between primary intestinal lymphoma and Crohn's disease

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World Journal of Gastroenterology 2024年第25期30卷 3155-3165页

作者： Meng-Jun Xiao Yu-Teng Pan Jia-He Tan hai-Ou li hai-Yan Wang Department of Radiology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021Shandong ProvinceChina Medical Science and Technology Innovation Center Shandong First Medical University&Shandong Academy of Medical SciencesJinan 250000Shandong ProvinceChina University of California DavisCA 95616United States Qilu Hospital Cheeloo College of MedicineShandong UniversityJinan 250012Shandong ProvinceChina

BACKGROUND Due to similar clinical manifestations and imaging signs,differential diagnosis of primary intestinal lymphoma(PIL)and Crohn's disease(CD)is a challenge in clinical *** To investigate the ability of radiomics combined with machine learning methods to differentiate PIL from *** We collected contrast-enhanced computed tomography(CECT)and clinical data from 120 patients form center 1.A total of 944 features were extracted singlephase images of CECT *** the last absolute shrinkage and selection operator model,the best predictive radiographic features and clinical indications were *** from 54 patients were collected at center 2 as an external validation set to verify the robustness of the *** area under the receiver operating characteristic curve,accuracy,sensitivity and specificity were used for *** A total of five machine learning models were built to distinguish PIL from *** on the results from the test group,most models performed well with a large area under the curve(AUC)(>0.850)and high accuracy(>0.900).The combined clinical and radiomics model(AUC=1.000,accuracy=1.000)was the best model among all *** Based on machine learning,a model combining clinical data with radiologic features was constructed that can effectively differentiate PIL from CD.

关键词： Primary intestinal lymphoma Crohn's disease Radiomics Machine learning Diagnosis

Supermassive black holes triggered by QCD axion bubbles

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Communications in Theoretical Physics 2024年第5期76卷 134-139页

作者： hai-Jun li Ying-Quan Peng Wei Chao Yu-Feng Zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still *** this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion *** this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after *** QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase *** consider a general case in which the axion bubbles are formed with the bubble effective angle θ_(eff)∈(0,π],leading to the minimum PBH mass∼■(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼■(10^(16))*** PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion

Precise control of page cache for containers

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Frontiers of Computer Science 2024年第2期18卷 17-30页

作者： Kun WANG Song WU Shengbang li Zhuo HUANG Hao FAN Chen YU hai JIN National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing Lab School of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Container-based virtualization isbecoming increasingly popular in cloud computing due to its efficiency and *** isolation is a fundamental property of *** works have indicated weak resource isolation could cause significant performance degradation for containerized applications and enhanced resource ***,current studies have almost not discussed the isolation problems of page cache which is a key resource for *** leverage memory cgroup to control page cache ***,existing policy introduces two major problems in a container-based ***,containers can utilize more memory than limited by their cgroup,effectively breaking memory ***,the Os kernel has to evict page cache to make space for newly-arrived memory requests,slowing down containerized *** paper performs an empirical study of these problems and demonstrates the performance impacts on containerized *** we propose pCache(precise control of page cache)to address the problems by dividing page cache into private and shared and controlling both kinds of page cache separately and *** do so,pCache leverages two new technologies:fair account(f-account)and evict on demand(EoD).F-account splits the shared page cache charging based on per-container share to prevent containers from using memory for free,enhancing memory *** EoD reduces unnecessary page cache evictions to avoid the performance *** evaluation results demonstrate that our system can effectively enhance memory isolation for containers and achieve substantial performance improvement over the original page cache management policy.

关键词： page cache memory cgroup container isolation cloud computing

High-temperature wetting behavior between slag and refractory

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Journal of Iron and Steel Research(International) 2024年第6期31卷 1304-1319页

作者： Yong-xin Wang Ya-ge li Ya-bo Gao Zhong Huang hai-jun Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Slag corrosion is one of the main factors of the damage of refractory,and its primary manifestations involve the melting of refractory in slag and the slag penetration into refractory,both of which are highly related to the wetting behavior between slag and *** high-temperature wettability could be characterized by parameters including the surface tension,adhesion work,and spreading coefficient of the slag on refractory surface,and it could be suppressed by altering the slag/refractory interface,thus resulting in an improved anti-corrosion *** this,the key knowledges of the slag corrosion,theory of wetting behavior and test of high-temperature contact angle were firstly ***,the major factors influencing the high-temperature slag wetting behavior were discussed based on the aspects of slag composition,refractory composition,and surface ***,the future research direction was proposed in this field.

关键词： High-temperature wetting Refractory Slag corrosion Surface tension