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Regionalization of Precipitation Regimes in China

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Atmospheric and Oceanic Science Letters 2009年第5期2卷 301-307页

作者： Chen Li-Juan Chen De-Liang Wang hui-Jun Yan Jing-hui National Climate Center Laboratory for Climate Studies Chinese Meteorological Administration Beijing 100081 China Department of Earth Sciences University of Gothenburg Gothenburg 40530 Sweden Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Precipitation regimes of China were mapped by using empirical orthogonal function (EOF) analysis with orthogonal rotation based on normalized monthly mean precipitation data at 400 stations from 1961 to *** regional boundaries were defined with the maximum-loading *** results identified 13 consistent and contiguous precipitation regions with distinct regional variations in China that are expected to reflect dominant regional patterns focusing on seasonal and interannual precipitation *** precipitation regionalization is operationally useful for seasonal and interannual climate predictions.

关键词： regionalization precipitation China REOF

Sliced Average Variance Estimation for Tensor Data

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 630-655页

作者： Chuan-quan LI Pei-wen XIAO Chao YING Xiao-hui LIU School of Statistics Jiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013China Biostatistics and Medical Informatics University of Wisconsin MadisonMadison 53726USA

Tensor data have been widely used in many fields,e.g.,modern biomedical imaging,chemometrics,and economics,but often suffer from some common issues as in high dimensional *** to find their low-dimensional latent structure has been of great interest for *** this end,we develop two efficient tensor sufficient dimension reduction methods based on the sliced average variance estimation(SAVE)to estimate the corresponding dimension reduction *** first one,entitled tensor sliced average variance estimation(TSAVE),works well when the response is discrete or takes finite values,but is not■consistent for continuous response;the second one,named bias-correction tensor sliced average variance estimation(CTSAVE),is a de-biased version of the TSAVE *** asymptotic properties of both methods are derived under mild *** and real data examples are also provided to show the superiority of the efficiency of the developed methods.

关键词： tensor data sliced average variance estimation sufficient dimension reduction central subspace

Thermodynamic prediction of thermal diffusivity and thermal conductivity in Mg–Zn–La/Ce system

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Journal of Materials Science & Technology 2022年第2期97卷 147-155页

作者： Tianci Xie hui Shi Hongbin Wang Qun Luo Qian Li Kuo-Chih Chou State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

Basic thermal properties and mechanical properties are critical parameters for the structural magnesium *** atoms and second phases can improve mechanical properties,but are deteriorating the heat dissipation *** experimental determination of alloys,it is found that REMg12 phases have fewer negative impacts on thermal diffusivities thanτ;*** the same intermetallic compound,the solute atom Zn have more negative influences on thermal diffusivities of Mg-Zn-La/Ce alloys than the content of second *** order to quantitatively evaluate thermal conductivities and further design Mg alloys with both high strength and high thermal conductivity,a calculated method is provided to describe the thermal diffusivity of alloys as a function of alloy composition and phase constitution.A set of parameters for expression of thermal diffusivity of Mg-Zn-La/Ce alloys were obtained through assessing the experimental *** thermal conductivities of Mg-Zn-La/Ce system were predicted and agreed well with experimental values with calculation error of 1.6%and standard error of±3.0 W/(m K).The calculation method considering thermal diffusivity resistivity improves the calculation accuracy and would be physically significant.

关键词： Mg-Zn-La/Ce alloys Thermal conductivity Mechanical properties CALPHAD Thermodynamics

Association between retinopathy,nephropathy,and periodontitis in type 2 diabetic patients:a Meta-analysis

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International Journal of Ophthalmology(English edition) 2021年第1期14卷 141-147页

作者： hui-Qun Wu Xiao Wei Jin-Yi Yao Jian-Yan Qi hui-Min Xie Ai-Min Sang Kui Jiang Department of Medical Informatics Medical School of Nantong UniversityNantong 226001Jiangsu ProvinceChina Department of Ophthalmology Affiliated Hospital of Nantong UniversityNantong 226001Jiangsu ProvinceChina

AIM:To verify the association between retinopathy,nephropathy,and periodontitis in type 2 diabetic(T2 D)***:Several electronic databases were available for our comprehensive search including China National Knowledge Infrastructure(CNKI),Chinese VIP Information(VIP),Wanfang,Web of Science,ScienceDirect and PubMed and were queried for relevant citations(updated to Mar.2019).RevMan was utilized to perform Meta analysis and publication bias *** evaluation of the methodological quality of included studies,a fixed or random effect model was utilized to analyze data from included ***:A total of eight articles were finally included in this Meta *** all 3987 subjects,there were 1207 T2 D patients accompanying with microvascular complications and 1734 patients with periodontitis as *** Meta forest plot presented little heterogeneity of the eight studies(P<0.00001,I^(2)=89%).The total effect demonstrated periodontitis was associated with overall microvascular complications(OR:1.96,95%CI:1.67-2.30,Z=8.25,P<0.00001).Subgroup investigations among the studies in Asian(OR:2.33,95%CI:1.91-2.85)and North American(OR:1.42,95%CI:1.08-1.86)populations confirmed the existed association between retinopathy,nephropathy,and *** the strength of such associations between periodontitis and diabetic microvascular complications were more obvious in the Asians than North *** the results indicated that periodontitis was associated with diabetic retinopathy(OR:3.77,95%CI:2.71-5.24),diabetic nephropathy(OR:1.55,95%CI:1.24-1.94)in T2 D ***:The periodontitis is associated with diabetic retinopathy,diabetic nephropathy among T2 D patients and further large sample size clinical trials are in need to confirm the findings.

关键词： periodontitis diabetic retinopathy diabetic nephropathy diabetes Meta-analysis

Unloading damage patterns of rock slopes in open pit mines and analyses of their mechanisms

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Journal of Mountain Science 2023年第12期20卷 3648-3664页

作者： WANG Jian-ming ZHOU Zi-han DOU Wei CHEN Zhong-hui School of Engineering Management Shanxi Vocational University of Engineering Science and TechnologyTaiyuan 030000China Department of Civil Engineering Tsinghua UniversityBeijing 100084China China Construction Sixth Engineering Bureau CORP. LTDNanjing 210000China School of Mechanics&Civil Engineering China University of Mining and TechnologyBeijing 100083China

The stability of slopes is essential for ensuring safe production in open-pit *** and managing the deformation and failure of the slope rock mass becomes more challenging as the slope height *** investigate the damage patterns of slopes with varying heights,three slope models were developed based on a rock slope in Dagushan,*** deformation failure processes of slopes under the influence of excavation and unloading were analyzed using the base friction test method in combination with digital image technology *** results supported the following findings:(1)Unloading tensile stress caused lateral partitioning in the *** the foot and top of the slope underwent initial tensile cracks.(2)The destabilization mechanism of unloading deformation in slopes of different heights involved a combination of traction at the foot of the slope or pushing at the top of the slope,followed by accelerated deformation,deceleration creep,and overall destabilization.(3)The unloading damage patterns of slopes at different heights were summarized as follows:compression tension cracking,traction,and slip damage for medium and low slopes;compression tension cracking,traction,and slip failure for the upper part of high slopes;and relaxation tension cracking,pushing,traction,and slip failure for the lower ***,the upper part of ultra-high slopes exhibited compression tension cracking,traction,and slip failure,while the middle and lower parts displayed relaxation tension cracking,pushing,traction,and slip ***,numerical simulations were conducted to verify the results of the test analyses,which demonstrated good *** research results were of great engineering value for proposing effective safety management measures for high slopes.

关键词： Excavation and unloading Displacement field Deformation mechanism Damage pattern Base friction test

A Study on Non-coplanar Baseline Effects for Mingantu Spectral Radioheliograph

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Research in Astronomy and Astrophysics 2022年第10期22卷 111-118页

作者： Qiu-Ping Yang Feng Wang hui Deng Ying Mei Wei Wang Yunnan Observatories Chinese Academy of SciencesKunming 650216China Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China University of Chinese Academy of Sciences Beijing 100049China Center of Astrophysics Guangzhou UniversityGuangzhou 510006China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

As a dedicated solar radioheliograph,the MingantU SpEctral RadioHeliograph(MUSER)has a maximum baseline of more than 3000 m and a frequency range of 400 MHz–15 *** to the classical radio interferometry theory,the non-coplanar baseline effect(i.e.,w-term effect)would be considered and calibrated for such a radio ***,little previous literature made the qualitative or quantitative analyses on w-term effects of solar radioheliograph *** study proposes a complete quantitative analysis of w-term effects for the *** a brief introduction of the MUSER,we systematically investigate the baseline variations over a year and analyze the corresponding variations of *** further studied the effects of the w-term in the imaging for the specified extended source,i.e.,the *** discussed the possible effects of the w-term,such as image distortion and so *** simulated results show that the w-term is an essential and unavoidable issue for solar radio imaging with high spatial resolution.

关键词： instrumentation interferometers-Sun radio radiation-methods data analysis

Rock characteristics and dynamic fragmentation process of the 2018 Daanshan rockslide in Beijing,China

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Journal of Mountain Science 2023年第2期20卷 448-465页

作者： FAN Tian-zhen AN hui-cong OUYANG Chao-jun WANG Dong-po State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China Key laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

This study investigated the failure mechanism associated with the rock mass structure and the dynamic fragmentation process of blocky rocks of the 2018 Daanshan rockslide that occurred on 11 August,*** was found that the initially collapsed rock of this rockslide was partitioned along the unconformity and strata *** analyzed how the unique rock mass structure,coupled with the road cut and the antecedent rainfall,jointly resulted in its *** on the rock types and geological structures,the initial stratified configuration of a discrete element model was setup to reveal the influences of the local *** numerical model was divided into three *** 1 is the basalt of the Nandaling Formation,the normal and shear stiffnesses of the basalt particles are set as 80 MPa and 40 *** 2 and 3 are the sandstones interbedded with mudstone and sandstone of the Shihezi Formation,and the normal and shear stiffnesses of these parts were set as 6 MPa and 10 MPa,*** dynamic process of the rockslide,particularly the rock fragmentation process,was numerically analyzed using a 3D discrete element *** numerical results were compared with real-time videos and field *** results show that the rock fragmentation and the final deposition range match well with the real disaster phenomenon,and the calculation accuracy of the rockslide reaches 82.41%.Moreover,a parameter sensitivity analysis was conducted,and classical uniform models under different bonding forces were established;the stratified model can better restore the true state of the fragmentation,movement,and deposition processes of ***,for complicated rocks with significant differences in lithology,clarifying the rock mass stratigraphy is essential for an accurate reconstruction of the dynamic process of rockslides.

关键词： Discrete element method Rockslide Stratified model Numerical modeling Fragmentation Daanshan rockslide

Thermally Chargeable Proton Capacitor Based on Redox-Active Effect for Energy Storage and Low-Grade Heat Conversion

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Energy & Environmental Materials 2023年第1期6卷 384-391页

作者： Yufeng An Zhiwei Li Yao Sun Zhijie Chen Jiangmin Jiang hui Dou Xiaogang Zhang Jiangsu Key Laboratory of Electrochemical Energy Storage Technologies College of Material Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 211106China

Thermal energy is abundantly available in our daily life and industrial production,and especially,low-grade heat is often regarded as a *** and utilizing this ignored energy by low-cost and simple technologies may become a smart countermeasure to relieve the energy ***,a unique device has been demonstrated to achieve high value-added conversion of low-grade heat by introducing redox-active organic alizarin(AZ)onto N-doped hollow carbon nanofibers(N–HCNF)***-prepared N–HCNF/AZ can deliver a high specific capacitance of 514.3 F g^(-1)(at 1 A g^(-1))and an outstanding rate capability of 60.3%even at 50 A g^(-1).Meanwhile,the assembled symmetric proton capacitor can deliver a high energy density of 28.0 Wh kg^(-1) at 350.0 W kg^(-1) and a maximum power density of 35.0 kW kg^(-1) at 17.0 Wh kg^(-1).Significantly,the thermally chargeable proton capacitors can attain a surprisingly high Seebeck coefficient of 15.3 mV K^(-1) and a power factor of 6.02µW g^(-1).Taking advantage of such high performance,a satisfying open-circuit voltage of 481.0 mV with a temperature difference of 54 K is *** research provides new insights into construction of high value-added energy systems requiring high electrochemical performances.

关键词： capacitors low-grade heat redox-active effect thermal chargeability

Blockage of the Deep-Sea Mining Pump Transporting Large Particles with Different Sphericity

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China Ocean Engineering 2023年第2期37卷 343-352页

作者： TENG Shuang KANG Can LI Ming-hui QIAO Jin-yu DING Ke-jin School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China Zibo Product Quality Testing Research Institute Zibo 255063China Shanghai Marine Equipment Research Institute Shanghai 200031China

The present study aims to plumb blockage of the deep-sea mining pump transporting large particles with different shapes. A numerical work was performed through combining the computational fluid dynamics(CFD) technique and the discrete element method(DEM). Six particle shapes with sphericity ranging from 0.67 to 1.0 were selected. A velocity triangle is built with the absolute, relative, and circumferential velocities of particles. Velocity triangles with absolute velocity angles ranging from 90° to 180° prevail in the first-stage impeller. With declining sphericity, more particles follow the velocity triangle with absolute velocity angles ranging from 0° to 90°, which weakens the ability of particles to pass through the flow passage. Furthermore, the forces acting on the particles traveling in the impeller passage are analyzed. Large particles, especially non-spherical ones, suffer from high centrifugal force and therefore move along the suction surface of the impeller blades. Non-spherical particles undergo great drag force as a result of large surface area. The distribution of drag force angles is featured by two peaks, and one vanishes due to *** particle sphericity declines, both magnitude and angle of the pressure gradient force decrease. Variation of the drag force and the pressure gradient force causes clockwise deflection of the centripetal force, resulting in deflection and elongation of particle trajectory, which increases the possibility of blockage.

关键词： deep-sea mining pump particle sphericity velocity triangle force angle particle trajectory blockage