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HYDRODYNAMIC MODEL OF THE WEIS-FOGH HYDROFOIL

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Journal of Hydrodynamics 1996年第4期8卷 35-39页

作者： Zhang She-sheng wu xiu-heng Wang Xian-fu(Department of mathematics, wuhan Transportation University, wuhan 430063, P. R. China) wuhan Transportation Univ Wuhan China

The paper discusses a mathematic model of the Weis-Fogh hydrofoil under the flow upstream with a separation vortex. The analysis makes use of a single-vortex model. We establish the motion equation of the vortex and the initial condition. Applying the complex function theory, we also obtain the analytic formula of the hydrodynamic integrations'which have the complex parameter and the singularity POint. The numeric results compare well with experiment.

关键词： hydrofoil mathematic model hydrodynamic force

Simulation of roof snow loads based on a multi-layer snowmelt model:Impact of building heat transfer

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Building Simulation 2024年第6期17卷 907-932页

作者： Xuanyi Zhou heng Chen Yue wu Tiange Zhang State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai200092China

To investigate the impact of building heat transfer on roof snow loads,roof snow loads and snow load thermal coefficients from 61 Chinese sites over a period of 50 years are simulated based on basic meteorological data such as temperature,humidity,wind speed,and precipitation,and a multi-layer snowmelt model considering the building heat ***,the accuracy of the multi-layer snowmelt model is validated using the data of observed ground snow load and roof snow melting *** relationship between meteorological conditions,snow cover characteristics,and thermal coefficients of snow loads in three representative sites is then ***,the characteristics of thermal coefficients in each zone are analyzed by combining them with the statistical results of meteorological data from 1960 to 2010,and the equations of thermal coefficients in different zones on indoor temperatures and roof heat transfer coefficients are fitted ***,the equations in this paper are compared with the thermal coefficients in the main snow load *** results indicate that the snowmelt model using basic meteorological data can effectively provide samples of roof snow *** the cold zone where the snow cover lasts for a long time and does not melt easily,the thermal coefficients of the snow loads on the heating buildings are lower than those in the warm zone due to the long-term influence of the heat from inside the *** coefficients are negatively correlated with indoor temperatures and roof heat transfer *** the indoor temperature is too low or the roof insulation is good,the roof snow load may exceed the ground snow *** thermal coefficients for heated buildings in the main snow load codes are more conservative than those calculated in this paper,and the thermal coefficients for buildings with lower indoor temperatures tend to be smaller.

关键词： snowmelt model roof snow load building heat transfer thermal coefficient load code

Multi-endpoint assays reveal more severe toxicity induced by chloraminated effluent organic matter than chloraminated natural organic matter

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Journal of Environmental Sciences 2024年第1期135卷 310-317页

作者： Hai-Yan Wang De-xiu wu Ye Du Xiao-Tong Lv Qian-Yuan wu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environmental Protection Key Laboratory of Microorganism Application and Risk Control Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China College of Architecture and Environment Sichuan UniversityChengdu 610000China

Disinfection by chloramination produces toxic byproducts and the difference in toxicity of reclaimed and drinking water treated by chloramination remains *** study investigated cytotoxic effects at the same concentrations of dissolved organic matter and showed that chloraminated effluent organic matter(EfOM)induced 1.7 times higher cytotoxicity than chloraminated natural organic matter(NOM)applied to simulate drinking *** EfOM induced more reactive nitrogen species than chloraminated NOM,and chloraminated EfOM and NOM induced similar and higher levels of reactive oxygen species than the negative control,***,intracellular macromolecule damage indicated by DNA/RNA damage marker 8–hydroxy-(deoxy)guanosine and the intracellular protein carbonyl concentration induced by chloraminated EfOM was higher and slightly more than that induced by chloraminated NOM,*** data were consistent with the effects on cell physiological *** cycle arrest mainly occurred in G2 phase by chloraminated EfOM and *** apoptotic cells,which could return to normal,increased upon exposure to high concentrations of chloraminated EfOM and ***,necrotic cells were significantly increased from 0.5%to 2.5%when the concentration increased from 20-to 60-fold chloraminated EfOM,but were not obviously changed by chloraminated *** results indicated that the comprehensive intracellular changes induced by toxic substances in chloraminated EfOM were more irreversible and induced more cell death than chloraminated NOM.

关键词： Cytotoxicity Intracellular active nitrogen/oxygen Intracellular oxidative damage Cell necrosis Reclaimed water

One-step hydrothermal synthesis of Cit-NaYbF_(4):Er^(3+)nanocrystals with enhanced red upconversion emission for in vivo fluorescence molecular tomography

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Journal of Rare Earths 2024年第1期42卷 36-45,I0002页

作者： Xiaoli Luo Qichen Chen Hongbo Guo heng Zhang Xiaowei He wu Zhao School of Mathematics and Computer Science Ningxia Normal UniversityGuyuan756099China School of Information Science and Technology Northwest UniversityXi'an710127China

Fluorescence imaging techniques represent essential tools in in vitro,preclinical,and clinical *** this study,an improved one-step hydrothermal method to synthesize citric acid(CA)modifiedα-NaYbF_(4):2%Er^(3+)nanocrystals was *** introduction of various doping ions into NaYbF_(4):2%Er^(3+)and the different valence states of the same ions affect both the crystal size and upconversion luminesce *** fore,we investigated the upconversion luminesce nce enha ncement of NaYbF_(4):2%Er^(3+)by ion doping and find that the upconversion luminescence intensity of the upconversion nanoparticles(UCNPs)co-doped with 5 mol%Fe^(2+)ions shows the greatest enhancement,especially for red emission at654 ***,HeLa cells incubated with UCNPs allow for imaging with strong red upconversion emission detectio *** laser scanning microscope(CLSM)fluorescent images of HeLa cells indicate that NaYbF_(4):2%Er/5%Fe^(2+)leads to a clear outline and improves visualization of the cell *** addition,the CA coated NaYbF_(4):2%Er^(3+)/5%Fe^(2+)nanoparticles and NaYbF_(4):2%Er^(3+)/5%Fe^(2+)show low cytotoxicity in HeLa *** imaging reveals the efficiency of these UCNPs to analyze the lungs,liver,and ***,these results indicate that the Cit-NaYbF_(4):2%Er^(3+)/5%Fe^(2+)UCNPs are efficient nanoprobes for fluorescence molecular to mography.

关键词： Hydrothermal method Fe^(2+)ion doping Tuning size Nanoprobes Fluorescence imaging Rare earths

Polypore funga and species diversity in tropical forest ecosystems of Africa,America and Asia,and a comparison with temperate and boreal regions of the Northern Hemisphere

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Forest Ecosystems 2024年第4期11卷 391-400页

作者： heng Zhao Yingda wu Zhirong Yang Honggao Liu Fang wu Yucheng Dai Yuan Yuan State Key Laboratory of Efficient Production of Forest Resources School of Ecology and Nature ConservationBeijing Forestry UniversityBeijing 100083China Key Laboratory of Forest and Grassland Fire Risk Prevention Ministry of Emergency ManagementChina Fire and Rescue InstituteBeijing 102202China Yunnan Key Laboratory of Gastrodia and Fungi Symbiotic Biology Zhaotong UniversityZhaotong 657000China Yunnan Engineering Research Center of Green Planting and Processing of Gastrodia Zhaotong UniversityZhaotong 657000China

Polypores play a cru cial role in energy recycling and forest regeneration in forest *** majority of them are wood degraders;some are forest pathogens and others are ectomycorrhizal *** basidiocarps provide food and shelter for many organisms,mostly invertebrates,but also some vertebrates,as well as food and medicine for *** extensive research on the species diversity and phylogenetic relationships of polypores in recent years,there remains a lack of comprehensive understanding of their distribution patterns and species composition at the large *** of polypores from the tropical zone,including tropical Africa,tropical America,and tropical Asia,were analyzed for species diversity,distribution patterns,major taxa,and nutritional modes.A total of 1,902 polypore species was found in the three regions,representing 8 orders,46families,and 250 genera of *** orders Polyporales(especially the family Polyporaceae)and Hymenochaetales(especially the family Hymenochaetaceae)had the most prolific taxa,with their species accounting for 93.4%of the total polypores *** of 1,565(or 82.3%)of the total 1,902 species were found in only one of the three regions studied,and we treat them temporarily as"regional endemic species".Only 141species were shared among all three regions,accounting for a mere 7.4%.Tropical Africa and tropical America had the greatest number of shared species and the highest S?rensen similarity index(SC)*** forests had a higher species richness compared with temperate to boreal forests of the Northern Hemisphere,and in addition,also a higher proportion of white rot polypores compared to brown rot and ectomycorrhizal *** study outlines the distribution patterns and species diversity of polypores in the world,shedding light on their ecological significance in diverse ecosystems.

关键词： Agaricomycetes Macrofungi Species composition Wood-decay fungi

RESEARCH AND PROGRESS OF WEISFOGH MECHANISM HYDRODYNAMICS

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Journal of Hydrodynamics 1999年第3期11卷 55-60页

作者： Zhang She sheng, wu xiu heng, Wan Xian fu Department of Mathematics, wuhan Transportation Univercity, wuhan 430063, P.R.China (Received Sep. 28, 1998)

Attention is focused on the research and progress of Weis Fogh mechanism hydrodynamics in this paper. We review some physical models and mathematical models of Weis Fogh mechanism, and also describe some analytic me... 详细信息

关键词： Weis Fogh mechanism hydrodynamics mathematical model

Single-structure 3-axis Lorentz force magnetometer based on an AlN-on-Si MEMS resonator

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Microsystems & Nanoengineering 2024年第3期10卷 75-86页

作者： Cheng Tu Xu-heng Ou-Yang Ying-jie wu Xiao-sheng Zhang School of Integrated Circuit Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

This work presents a single-structure 3-axis Lorentz force magnetometer(LFM)based on an AlN-on-Si MEMS *** operation of the proposed LFM relies on the flexible manipulation of applied excitation currents in different directions and frequencies,enabling the effective actuation of two mechanical vibration modes in a single device for magnetic field measurements in three ***,the excited out-of-plane drum-like mode at 277 kHz is used for measuring the x-and y-axis magnetic fields,while the in-plane square-extensional mode at 5.4 MHz is used for measuring the z-axis magnetic *** different configurations of applied excitation currents ensure good crossinterference immunity among the three *** to conventional capacitive LFMs,the proposed piezoelectric LFM utilizes strong electromechanical coupling from the AlN layer,which allows it to operate at ambient pressure with a high *** understand and analyze the measured results,a novel equivalent circuit model for the proposed LFM is also reported in this work,which serves to separate the effect of Lorentz force from the unwanted capacitive *** demonstrated 3-axis LFM exhibits measured magnetic responsivities of 1.74 ppm/mT,1.83 ppm/mT and 6.75 ppm/mT in the x-,y-and z-axes,respectively,which are comparable to their capacitive counterparts.

关键词： resonator Lorentz structure

A Power Data Anomaly Detection Model Based on Deep Learning with Adaptive Feature Fusion

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Computers, Materials & Continua 2024年第6期79卷 4045-4061页

作者： xiu Liu Liang Gu Xin Gong Long An Xurui Gao Juying wu State Grid Information&Telecommunication Co.of SEPC Big Data CenterTaiyuan030000China

With the popularisation of intelligent power,power devices have different shapes,numbers and *** means that the power data has distributional variability,the model learning process cannot achieve sufficient extraction of data features,which seriously affects the accuracy and performance of anomaly ***,this paper proposes a deep learning-based anomaly detection model for power data,which integrates a data alignment enhancement technique based on random sampling and an adaptive feature fusion method leveraging dimension *** at the distribution variability of power data,this paper developed a sliding window-based data adjustment method for this model,which solves the problem of high-dimensional feature noise and low-dimensional missing *** address the problem of insufficient feature fusion,an adaptive feature fusion method based on feature dimension reduction and dictionary learning is proposed to improve the anomaly data detection accuracy of the *** order to verify the effectiveness of the proposed method,we conducted effectiveness comparisons through elimination *** experimental results show that compared with the traditional anomaly detection methods,the method proposed in this paper not only has an advantage in model accuracy,but also reduces the amount of parameter calculation of the model in the process of feature matching and improves the detection speed.

关键词： Data alignment dimension reduction feature fusion data anomaly detection deep learning

Productivity in the Southern Ocean Antarctic Zone during the Northern Hemisphere Glaciation(NHG)and its link to atmospheric pCO_(2)

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Science China Earth Sciences 2024年第7期67卷 2242-2252页

作者： Yiming wu Jingteng GUO Xiangyu ZHAO Wenshen XIAO heng LIU Zhifang XIONG Tiegang LI Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266237China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratoryof Polar Ecosystem and Climate Change Shanghai Jiao Tong UniversityMinistry of EducationShanghai 200030China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China

A decrease in atmospheric CO_(2)partial pressure(pCO_(2))is considered an important prerequisite for the onset and intensification of Northern Hemisphere Glaciation(NHG).However,how the ocean sequestered missing CO_(2)during the NHG is still *** in surface productivity and deep ventilation in the Southern Ocean(SO)have been proposed to explain the variations in atmospheric pCO_(2)over the last eight glacial cycles,but it is unclear whether these mechanisms contributed to the decrease in atmospheric pCO_(2)during the *** titanium-normalized contents and mass accumulation rates of biogenic opal and total organic carbon from the International Ocean Discovery Program(IODP)Expedition 374 Site U1524A,we reconstruct the productivity in the Ross Sea,Antarctica,from 3.3 Ma to 2.4 *** productivity records exhibit a long-term decreasing trend and several distinct phased evolutionary ***,the local productivity fluctuated dramatically during 3.3-3.0 Ma,decreased gradually during 3.0-2.6 Ma,and remained relatively constant during 2.6-2.4 *** comparing productivity with its potential influences,we infer that the phased and long-term evolutions of productivity were mainly controlled by changes in deep ocean *** ice expansion might have decreased productivity during 3.3-3.0 Ma by light *** in eolian dust input have little effect on *** analysis revealed no coupling linkage between productivity and atmospheric pCO_(2),indicating that the productivity in the SO Antarctic Zone(AZ)was not the main factor controlling the atmospheric CO_(2)decrease during the *** improve our understanding of the role of SO processes in the NHG,further studies should focus on the potential influences of deep ocean ventilation on atmospheric pCO_(2)in the AZ,and similar studies should also be extended to the sea area in the Subantarctic Zone.

关键词： Ross Sea Biogenic opal Total organic carbon Deep ocean ventilation Sea ice Ocean carbon cycle