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Probabilistic Response and Short-Term Extreme Load Estimation of Offshore Monopile Wind Turbine Towers by Probability Density Evolution Method

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China Ocean Engineering 2022年第3期36卷 363-371页

作者： ZHANG hui XU Ya-zhou School of Building Services Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055China School of Civil Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

A new analysis framework based on probability density evolution method(PDEM)and its Chebyshev collocation solution are introduced to predict the dynamic response and short-term extreme load of offshore wind turbine(OWT)towers subjected to random sea state.With regard to the stochastic responses,random function method is employed to generate samples of sea elevation,the probability density evolution equation(PDEE)is solved to calculate time-variant probability density functions of structural responses.For the probabilistic load estimation,a FAST model of NREL 5MW offshore turbine is established to obtain samples of bending moment at the tower base.The equivalent extreme event theory is used to construct a virtual stochastic process(VSP)to assess the short-term extreme load.The results indicate that the proposed approach can predict time-variant probability density functions of the structural responses,and shows good agreement with Monte Carlo simulations.Additionally,the predicted short-term extreme load can capture the fluctuation at the tail of the extreme value distribution,thus is more rational than results from the typical distribution models.Overall,the proposed method shows good adaptation,precision and efficiency for the dynamic response analysis and load estimation of OWT towers.

关键词： offshore wind turbine probability density evolution method Chebyshev collocation matrix exponential Monte Carlo

Gorenstein AC-Projective and AC-Injective Modules over Formal Triangular Matrix Rings

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Algebra Colloquium 2022年第3期29卷 475-490页

作者： Dejun Wu hui zhou Department of Applied Mathematics Lanzhou University of Technology Lanzhou 730050China

Let A and B be rings and U a(B,A)-bimodule.If BU is flat and UA is finitely generated projective(resp.,BU is finitely generated projective and UA is flat),then the characterizations of level modules and Gorenstein AC-projective modules(resp.,absolutely clean modules and Gorenstein AC-injective modules)over the formal triangular matrix ring T=(A0 UB)are given.As applications,it is proved that every Gorenstein AC-projective left T-module is projective if and only if each Gorenstein AC-projective left A-module and B-module is projective,and every Gorenstein AC-injective left T-module is injective if and only if each Gorenstein AC-injective left A-module and B-module is injective.Moreover,Gorenstein AC-projective and AC-injective dimensions over the formal triangular matrix ring T are studied.

关键词： formal triangular matrix ring Gorenstein AC-projective module level module absolutely clean module

Insider Trading with a Random Deadline under Partial Observations:Maximal Principle Method

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Acta Mathematicae Applicatae Sinica 2022年第4期38卷 753-762页

作者： Kai XIAO Yong-hui zhou School of Mathematical Sciences Guizhou Normal UniversityGuiyang 550001China School of Big Data and Computer Science Guizhou Normal UniversityGuiyang 550001China

For a revised model of Caldentey and Stacchetti(Econometrica,2010)in continuous-time insider trading with a random deadline which allows market makers to observe some information on a risky asset,a closed form of its market equilibrium consisting of optimal insider trading intensity and market liquidity is obtained by maximum principle method.It shows that in the equilibrium,(i)as time goes by,the optimal insider trading intensity is exponentially increasing even up to infinity while both the market liquidity and the residual information are exponentially decreasing even down to zero;(ii)the more accurate information observed by market makers,the stronger optimal insider trading intensity is such that the total expect profit of the insider is decreasing even go to zero while both the market liquidity and the residual information are decreasing;(iii)the longer the mean of random time,the weaker the optimal insider trading intensity is while the more both the residual information and the expected profit are,but there is a threshold of trading time,half of the mean of the random time,such that if and only if after it the market liquidity is increasing with the mean of random time increasing.

关键词： continuous-time insider trading random deadline partial observations filtering theory maximal principle

Circulation in the South China Sea is in a state of forced oscillation:Results from a simple reduced gravity model with a closed boundary

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Acta Oceanologica Sinica 2022年第7期41卷 1-12页

作者： Rui Xin Huang hui zhou Woods Hole Oceanographic Institution Woods HoleFalmouthMassachusetts02543USA Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao266071China Laboratory for Ocean Dynamics and Climate Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao266237China University of Chinese Academy of Sciences Beijing100049China

The South China Sea(SCS)is a narrow semi-enclosed basin,ranging from 4°–6°N to 21°–22°N meridionally.It is forced by a strong annual cycle of monsoon-related wind stress.The Coriolis parameter f increases at least three times from the southern basin to the northern basin.As a result,the basin-cross time for the first baroclinic Rossby wave in the southern part of the basin is about 10-times faster than that in the northern part,which plays the most vitally important role in setting the circulation.At the northernmost edge of SCS,the first baroclinic Rossby wave takes slightly less than 1 year to move across the basin,however,it takes only 1–2 months in the southernmost part.Therefore,circulation properties for a station in the model ocean are not solely determined by the forcing at that time instance only;instead,they depend on the information over the past months.The combination of a strong annual cycle of wind forcing and large difference of basin-cross time for the first baroclinic Rossby wave leads to a strong seasonal cycle of the circulation in the SCS,hence,the circulation is dominated by the forced oscillations,rather than the quasi-steady state discussed in many textbooks.The circulation in the SCS is explored in detail by using a simple reduced gravity model forced by seasonally varying zonal wind stress.In particular,for a given time snap the western boundary current in the SCS cannot play the role of balancing mass transport across each latitude nor balancing mechanical energy and vorticity in the whole basin.In a departure from the steady wind-driven circulation discussed in many existing textbooks,the circulation in the SCS is characterized by the imbalance of mechanical energy and vorticity for the whole basin at any part of the seasonal cycle.In particular,the western boundary current in the SCS cannot balance the mass,mechanical energy,and vorticity in the seasonal cycle of the basin.Consequently,the circulation near the western boundary cannot be interpreted in terms of the wind stress and therm

关键词： South China Sea ocean circulation annual cycle first baroclinic Rossby wave propagation western boundary current forced ossilation

Collective effects in an incompressible electronic liquid

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National Science Review 2023年第6期10卷 168-182页

作者： Jian-Jian Miao hui-Ke Jin Yi zhou Department of Physics The Chinese University of Hong Kong Department of Physics TQM Technische Universitat Munchen Institute of Physics Chinese Academy of Sciences Songshan Lake Materials Laboratory Kavli Institute for Theoretical Sciences & CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences

Starting from Landau’ s kinetic equation,we show that an electronic liquid in d=2,3 spatial dimensions depicted by a Landau-type effective theory will become incompressible on condition that the Landau parameters satisfy either(ⅰ) 1+F1s/d=0 or(ⅱ) F0s→+∞. Condition(ⅰ) is the Pomeranchuk instability in the current channel and suggests a quantum spin liquid(QSL) state with a spinon Fermi surface;while condition(ⅱ) means that the strong repulsion in the charge channel leads to a conventional charge and thermal insulator.In the collisionless regime(ωτ>>1) and the hydrodynamic regime(ωτ<<1),the zero and first sound modes have been studied and classified by symmetries,including the longitudinal and transverse modes in d=2,3 and the higher angular momentum modes in d=3.The sufficient(and/or necessary) conditions of these collective modes have been revealed.It has been demonstrated that some of these collective modes will behave in quite different manners under incompressibility condition(ⅰ) or(ⅱ).Possible nematic QSL states and a hierarchy structure for gapless QSL states have been proposed in d=3.

关键词： quantum spin liquid Landau-type effective theory collective modes zero sound first sound

Stabilization/solidification mechanisms of tin tailings and fuming slag-based geopolymers for different heavy metals

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FRONTIERS OF ENVIRONMENTAL SCIENCE & ENGINEERING 2024年第5期18卷 56-56页

作者： zhou, Xian Zhang, Zhengfu Yang, hui Kunming Univ Sci & Technol Sch Mat Sci & Engn Kunming 650093 Peoples R China Kunming Met Res Inst Co Ltd Kunming 650031 Peoples R China

Tin mine tailings (TMT) and fuming slag (FS) contain many heavy metals (As, Cr, Cu, Zn and Mn) that cause severe pollution to the environment. Herein, geopolymers were prepared using TMT, FS and flue gas desulfurization gypsum (FGDG) to immobilize heavy metals, and their compressive strength and heavy metal leaching toxicity were investigated. It was first determined that T4F5 (TMT:FS = 4:5) sample exhibited the highest compressive strength (7.83 MPa). T4F5 achieved 95% immobilization efficiency for As and Cr, and nearly 100% for Cu, Zn and Mn, showing good immobilization performance. A series of characterization analyses showed that heavy metal cations can balance the charge in the geopolymer and replace Al in the geopolymer structure to form covalent bonds. In addition, about 2%-20% of heavy metal Fe was immobilized in hydration products, heavy metal hydroxides and non-bridging Si-O and Al-O coordination with silica-aluminate matrices. AsO33- was oxidized into AsO43-, which may form Ca-As or Fe-As precipitates. Cr2O72- was converted to CrO42- under alkaline environment and then combined with OH- to form Cr(OH)3 precipitates. Mn2+ may react directly with dissolved silicate to form Mn2SiO4 and also form Mn(OH)2 precipitates. The unstable Mn(OH)2 can be further oxidized to MnO2. The heavy metal cations were immobilized in the silicoaluminate lattice, while the anions tended to form insoluble precipitates. These results may benefit the industry and government for better handling of TMT, FS and solid wastes containing the abovementioned five heavy metals.

关键词： Heavy metals Cementitious materials Tin tailings Stabilization/solidification Redox ORE PROCESSING RESIDUE MSWI FLY-ASH IMMOBILIZATION SOLIDIFICATION/STABILIZATION ADSORPTION SPECIATION BEHAVIOR CD(II) PB(II)

Regulatory role of exosomes in colorectal cancer progression and potential as biomarkers

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癌症生物学与医学:英文版 2023年第8期20卷 575-598页

作者： Juan hui Mingzhen zhou Guangzhou An hui Zhang Yuanyuan Lu Xin Wang Xiaodi Zhao Department of Gastroenterology Tangdu HospitalAir Force Medical UniversityXi’an 710038China State Key Laboratory of Cancer Biology and National Clinical Research Center for Digestive Diseases Xijing Hospital of Digestive DiseasesAir Force Medical UniversityXi’an 710032China Department of Radiation Protection Medicine Ministry of Education Key Laboratory of Hazard Assessment and Control in Special Operational EnvironmentFaculty of Preventive MedicineAir Force Medical UniversityXi’an 710032China Department of Traditional Chinese Medicine Tangdu HospitalAir Force Medical UniversityXi’an 710038China

Colorectal cancer(CRC)remains an enormous challenge to human health worldwide.Unfortunately,the mechanism underlying CRC progression is not well understood.Mounting evidence has confirmed that exosomes play a vital role in CRC progression,which has attracted extensive attention among researchers.In addition to acting as messengers between CRC cells,exosomes also participate in the CRC immunomodulatory process and reshape immune function.As stable message carriers and liquid biopsy option under development,exosomes are promising biomarkers in the diagnosis or treatment of CRC.In this review we have described and analyzed the biogenesis and release of exosomes and current research on the role of exosomes in immune regulation and metastasis of CRC.Moreover,we have discussed candidate exosomal molecules as potential biomarkers to diagnose CRC,predict CRC progression,or determine CRC chemoresistance,and described the significance of exosomes in the immunotherapy of CRC.This review provides insight to further understand the role of exosomes in CRC progression and identify valuable biomarkers that facilitate the clinical management of CRC patients.

关键词： Colorectal cancer exosome immunoregulation immunotherapy metastasis

Total Saponin Fraction of Dioscorea Nipponica Makino Improves Gouty Arthritis Symptoms in Rats via M1/M2 Polarization of Monocytes and Macrophages Mediated by Arachidonic Acid Signaling

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Chinese Journal of Integrative Medicine 2023年第11期29卷 1007-1017页

作者： zhou Qi SUN hui-juan ZHANG Xi-wu Research Institute of Chinese Medicine Heilongjiang University of Chinese MedicineHarbin(150040)China Graduate School Heilongjiang University of Chinese MedicineHarbin(150040)China

Objective:To explore the mechanism of effects of total saponin fraction from Dioscorea Nipponica Makino(TSDN)on M1/M2 polarization of monocytes/macrophages and arachidonic acid(AA)pathway in rats with gouty arthritis(GA).Methods:Seventy-two Sprague Dawley rats were randomly divided into 4 groups(n=18 in each):normal,model,TSDN at 160 mg/kg,and celecoxib at 43.3 mg/kg.Monosodium urate crystal(MSU)was injected into the rats’ankle joints to induce an experimental GA model.Blood and tissue samples were collected on the 3rd,5th,and 8th days of drug administration.Histopathological changes in the synovium of joints were observed via hematoxylin and eosin(HE)staining.The expression levels of arachidonic acid(AA)signaling pathway were assessed via real-time polymerase chain reaction(q PCR)and Western blot.Flow cytometry was used to determine the proportion of M1 and M2 macrophages in the peripheral blood.An enzyme-linked immunosorbent assay(ELISA)was used to detect interleukine(IL)-1β,tumor necrosis factoralpha(TNF-α),IL-4,IL-10,prostaglandin E_(2)(PGE_(2)),and leukotriene B4(LTB4).Results:HE staining showed that TSDN improved the synovial tissue.q PCR and Western blot showed that on the 3rd,5th and 8th days of drug administration,TSDN reduced the m RNA and protein expressions of cyclooxygenase(COX)2,microsomal prostaglandin E synthase-1 derived eicosanoids(m PGES-1),5-lipoxygenase(5-LOX),recombinant human mothers against decapentaplegic homolog 3(Smad3),nucleotide-binding oligomerization domain-like receptor protein 3(NALP3),and inducible nitric oxide synthase(i NOS)in rats’ankle synovial tissues(P<0.01).TSDN decreased COX1 m RNA and protein expression on 3rd and 5th day of drug administration and raised it on the 8th day(both P<0.01).It lowered CD68 protein expression on days 3(P<0.01),as well as m RNA and protein expression on days 5 and 8(P<0.01).On the 3rd,5th,and 8th days of drug administration,TSDN elevated the m RNA and protein expression of Arg1 and CD163(P<0.01).Flow cytometry results showed that TSDN decreased

关键词： Smad3 Blood mother

Effects of Total Saponins from Dioscorea Nipponica Makino on Monosodium Urate-Induced M1-Polarized Macrophages through Arachidonic Acid Signaling Pathway:An in vitro Study

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Chinese Journal of Integrative Medicine 2023年第1期29卷 44-51页

作者： zhou qi SUN hui-juan LIU Shu-min Research Institute of Chinese Medicine Heilongjiang University of Chinese MedicineHarbin150040China Graduate School Heilongjiang University of Chinese MedicineHarbin150040China Technological Innovation Team of Basic Theory Study Research of Institution of Higher Education in Heilongjiang Province Heilongjiang University of Chinese MedicineHarbin150040China

Objective To investigate and reveal the underlying mechanism of the effect of total saponins from Dioscoreae nipponica Makino(TSDN)on the arachidonic acid pathway in monosodium urate(MSU)crystal-induced M1-polarized macrophages.Methods M1 polarization of RAW264.7 cells were induced by 1µg/mL lipopolysaccharide(LPS).The methylthiazolyldiphenyl-tetrazolium bromide method was then used to screen the concentration of TSDN.MSU(500µg/mL)was used to induce the gouty arthritis model.Afterwards,10µg/L TSDN and 8µmol/L celecoxib,which was used as a positive control,were added to the above LPS and MSU-induced cells for 24 h.The mRNA and protein expressions of cyclooxygenase(COX)2,5-lipoxygenase(5-LOX),microsomal prostaglandin E synthase derived eicosanoids(mPGES)-1,leukotriene B(LTB)4,cytochrome P450(CYP)4A,and prostaglandin E_(2)(PGE_(2))were tested by real-time polymerase chain reaction and Western blotting,respectively.The enzyme-linked immunosorbent assay was used to test the contents of M1 markers,including inducible nitric oxid synthase(NOS)2,CD80,and CD86.Results TSDN inhibited the proliferation of M1 macrophages and decreased both the mRNA and protein expressions of COX2,5-LOX,CYP4A,LTB4,and PGE_(2)(P<0.01)while increased the mRNA and protein expression of mPGES-1(P<0.05 or P<0.01).TSDN could also significantly decrease the contents of NOS2,CD80,and CD86(P<0.01).Conclusion TSDN has an anti-inflammation effect on gouty arthritis in an in vitro model by regulating arachidonic acid signaling pathway.

关键词： gouty arthritis Dioscorea nipponica Makino arachidonic acid signaling pathway M1/M2 polarization