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On Proof of the C^1 Stability Conjecture

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Acta Mathematica Sinica,English Series 2005年第3期21卷 533-540页

作者： Yong ZHANG Shao bo.GAN School of Mathematical Sciences Soochow University Suzhou 215006 P. R. China School of Mathematical Sciences Peking University Beijing 100084 P. R. China

It seems that in Mane＇s proof of the C^1 Ω-stability conjecture containing in the famous paper which published in I. H. E. S. （1988）, there exists a deficiency in the main lemma which says that for f ∈F^1 （M） there exists a dominated splitting TMPi（f） =ei^s the direlf sum of E and F Fi^u（O 〈 i 〈 dim M） such that if ei^s is contracting, then Fi^u is expanding. In the first part of the paper, we give a proof to fill up this deficiency. In the last part of the paper, we, under a weak assumption, prove a result that seems to be useful in the study of dynamics in some other stability context.

关键词： The C^1 stability conjecture Dominated splitting Shadowing property Axiom A No-cycle condition

Influence of steel corrosion on axial and eccentric compression behavior of coral aggregate concrete column

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Frontiers of Structural and Civil Engineering 2021年第6期15卷 1415-1425页

作者： bo.DA Yan CHEN Hongfa YU Haiyan MA bo.YU Da CHEN Xiao CHEN Zhangyu WU Jianbo.GUO State Key Labo.atory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China College of Harbo.r Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Key Labo.atory of Coastal Disaster and Defence of Ministry of Education Hohai UniversityNanjing 210098China Guangxi Key Labo.atory of Disaster Prevention and Engineering Safety Guangxi UniversityNanning 530004China Department of Civil and Airport Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

To study the behavior of coral aggregate concrete(CAC)column under axial and eccentric compression,the compression behavior of CAC column with different types of steel and initial eccentricity(ei)were tested,and the deformation behavior and ultimate bearing capacity(Nu)were *** results showed that as the ei increases,the Nu of CAC column decreases ***,the steel corrosion in CAC column is severe,which reduces the steel section and steel strength,and decreases the Nu of CAC *** durability of CAC structures can be improved by using new organic coated *** the influence of steel corrosion and interfacial bo.d deterioration,the calculation models of Nu under axial and eccentric compression were presented.

关键词： coral aggregate concrete column axial compression eccentric compression steel corrosion calculation model

Optimal Operation of Energy Internet Based on User Electricity Anxiety and Chaotic Spatial Variation Particle Swarm Optimization

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Tsinghua Science and Technology 2018年第3期23卷 243-253页

作者： Dongsheng Yang Qianqian Chong bo.Hu Min Ma Department of Information Science and Engineering Northeastern University Liaoning Electric Power Company

Ignoring load characteristics and not considering user feeling with regard to the optimal operation of Energy Internet（ei） results in a large error in optimization. Thus, results are not consistent with the actual operating conditions. To solve these problems, this paper proposes an optimization method based on user Electricity Anxiety（EA） and Chaotic Space Variation Particle Swarm Optimization（CSVPSO）. First, the load is divided into critical load, translation load, shiftable load, and temperature load. Then, on the basis of the different load characteristics,the concept of the user EA degree is presented, and the optimization model of the ei is provided. This paper also presents a CSVPSO algorithm to solve the optimization problem because the traditional particle swarm optimization algorithm takes a long time and particles easily fall into the local optimum. In CSVPSO, the particles with lower fitness value are operated by using cross operation, and velocity variation is performed for particles with a speed lower than the setting threshold. The effectiveness of the proposed method is verified by simulation *** results show that the proposed method can be used to optimize the operation of ei on the basis of the full consideration of the load characteristics. Moreover, the optimization algorithm has high accuracy and computational efficiency.

关键词： Electricity Anxiety(EA) Energy Internet(ei) chaotic spatial variation particle swarm optimization optimal operation

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国内外自然资源与经济增长研究述评

技术经济与管理研究 2010年第1期 105-108页

作者：仲素梅武博南京审计学院江苏南京210029 南京河海大学江苏南京210098

自然资源是经济增长过程中的一个要素,理论上这个要素能够扩大生产可能性边界,但现实生活中自然资源常常阻碍了经济增长。文章通过查阅中外相关资料,就自然资源与经济增长关系的研究进展及理论成果做一个梳理和总结。

关键词：自然资源经济增长述评

Dynamics and Relationships of Ca,Mg,Fe in Litter,Soil Fauna and Soil in Pinus koraiensis-Broadleaf Mixed Forest

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Chinese Geographical Science 2008年第3期18卷 284-290页

作者： SONG bo.YIN Xiuqin ZHANG Yu DONG Weihua College of Urban and Environmental Sciences Northeast Normal University Changchun 130024 China

The Liangshui Natural Reserve in Heilongjiang Province of China was selected as the study area. The authors collected the samples of forest litter （Tilia amurensis, Fraxinus mandshurica, Pinus koraiensis, Acer mono, Betula costata, and mixed litter）, soil in humus horizon （0--5cm） and soil horizon （5-20cm）, and soil macrofauna （Oligochaeta, Geophiloporpha and Juliformia） from 2001 to 2002. The role of soil macrofauna in the material cycle was analyzed through comparing the macro-element contents among various parts of the subsystems and using enrichment index （El）. The results indicate that dynamic changes of various litters are very complicated. The contents of Fe in each kind of litter increase firstly, and then decrease in the study period. The changes of macro-element contents are greater in the broad-leaf litter than in the coniferous litter, and the mixed litter is in the middle level, but the differences among them are not significant. The contents of Mg and Fe in humus are higher than those in soil, but the contents of Ca in soil are higher than that in humus. The dynamic changes of macro-element contents in soil and soil fauna are not consistent with those in litter. The diplopod presented obvious enrichment of Ca and Mg （E1〉1）, but it does not significantly enrich Fe. Earthworm has a stronger enrichment ability of Fe than diplopod and scolopendra, but E1〈1. Soil fauna can make great influences on the material cycle of the subsystems.

关键词： soil fauna litter decomposition macro-element cycle Liangshui Natural Reserve

Novel high-voltage self-adaptive power device based on interface charge＊

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Chinese Physics B 2011年第2期20卷 408-415页

作者： Wu Li-Juan Hu Sheng-Dong Zhang bo.Li Zhao-Ji State Key Labo.atory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu 610054 China College of Communication Engineering Chengdu University of Information Technology Chengdu 610225 China College of Communication Engineering Chongqing University Chongqing 400044 China

This paper presents a novel high-voltage lateral double diffused metal-oxide semiconductor （LDMOS） with self- adaptive interface charge （SAC） layer and its physical model of the vertical interface electric field. The SAC can be self-adaptive to collect high concentration dynamic inversion holes, which effectively enhance the electric field of dielectric buried layer （ei） and increase breakdown voltage （BV）. The BV and ei of SAC LDMOS increase to 612 V and 600 V/tim from 204 V and 90.7 V/ttm of the conventional silicon-on-insulator, respectively. Moreover, enhancement factors of r/which present the enhanced ability of interface charge on ei are defined and analysed.

关键词： self-adaptive interface charge inversion holes dielectric layer electric field breakdown voltage

A comparison of deep learning methods for seismic impedance inversion

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Petroleum Science 2022年第3期19卷 1019-1030页

作者： Si-bo.Zhang Hong-Jie Si Xin-Ming Wu Shang-Sheng Yan Huawei Cloud ei Product Department Xi'anShaanxi710077China School of Earth and Space Sciences University of Science and Technology of ChinaHefeiAnhui230026China

Deep learning is widely used for seismic impedance inversion,but few work provides in-depth research and analysis on designing the architectures of deep neural networks and choosing the network *** paper is dedicated to comprehensively studying on the significant aspects of deep neural networks that affect the inversion *** experimentally reveal how network hyperparameters and architectures affect the inversion performance,and develop a series of methods which are proven to be effective in reconstructing high-frequency information in the estimated impedance *** demonstrate that the proposed multi-scale architecture is helpful to reconstruct more high-frequency details than a conventional ***,the reconstruction of high-frequency information can be further promoted by introducing a perceptual loss and a generative adversarial network from the computer vision *** importantly,the experimental results provide valuable references for designing proper network architectures in the seismic inversion problem.

关键词： Seismic inversion Impedance Deep learning Network architecture

Shape Optimization of Pressure Vessel Head Based on the Super-ellipse Equation

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Journal of Harbin Institute of Technology(New Series) 2013年第4期20卷 52-62页

作者： Yi-Ming Zhou bo.Wang Geng-Dong Cheng State Key Labo.atory of Structural Analysis for Industrial Equipment Dalian University of Technology

This paper studies optimal shape design of pressure vessel head subject to internal uniform *** optimization aims at minimizing its maximum stress while the volume of the vessel head remains no less than the standard ellipsoidal ***-ellipse curve is selected to describe the middle surface shape of the vessel head because it represents a large family of curves with only two or three parameters and makes the design and manufacture *** performance of different elements and element sizes of FEM modeling is carefully studied in view of computational cost,accuracy and noises of von Mises *** response surface of the maximum stress *** design parameters is approximated by a Kriging surrogate model with ei criterion for sampling adding,based on the parameter optimization which is carried out to search the optimal ***,it is shown by numerical comparison that the super-ellipsoidal head is better than the standard ellipsoidal head and the other vessel heads in the literature.

关键词： shape optimization super-ellipse function Kriging pressure vessel head sampling criterion

Temporal Variations in Soil CO_2 Efflux Under Diferent Land Use Types in the Black Soil Zone of Northeast China

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Pedosphere 2013年第5期23卷 636-650页

作者： HAN Xiao-Zeng LI Hai-bo.W. R. HORWATH National Field Research Station of Agro-Ecosystem in Hailun Northeast Institute of Geography and Agro-ecology Chinese Academy of Sciences College of Plant Sciences Jilin University of Agricultural Science and Technology Department of Land Air and Water Resources University of California

The quantification of soil CO2 effiux is crucial for better understanding the interactions between driving variables and C losses from black soils in Northeast China and for assessing the function of black soil as a net source or sink of atmospheric CO2 depending upon land use. This study investigated responses of soil CO2 effiux variability to soil temperature interactions with different soil moisture levels under various land use types including grassland, bare land, and arable （maize, soybean, and wheat） land in the black soil zone of Northeast China. The soil CO2 effiuxes with and without live roots, defined as the total CO2 efftux （FtS） and the root-free CO2 ei^lux （FrfS）, respectively, were measured from April 2009 to May 2010 using a static closed chamber technique with gas chromatography. The seasonal soil CO2 fluxes tended to increase from the beginning of the measurements until they peaked in summer and then declined afterwards. The mean seasonal FtS ranged from 20.3=h7.8 to 58.1~21.3 mg CO2-C m-2 h-1 for all land use types and decreased in the order of soybean land ~ grassland 〉 maize land ~ wheat land ） bare land, while the corresponding values of FrfS were relatively lower, ranging from 20.3~7.8 to 42.3~21.3 mg CO2-C m-2 h-1. The annual cumulative FtS was in the range of 107-315 g CO2-C m-2 across all land uses types. The seasonM CO2 effiuxes were significantly （P 〈： 0.001） sensitive to soil temperature at 10 cm depth and were responsible for up to 62% of the CO2 effiux variability. Correspondingly, the temperature coefficient Q10 values varied from 2.1 to 4.5 for the seasonal FtS and 2.2 to 3.9 for the FrfS during the growing season. Soil temperature interacting with soil moisture accounted for a significant fraction of the CO2 flux variability for FtS （up to 61%） and FrfS （up to 67%） via a well-defined multiple regression model, indicating that temperature sensitivity of C02 flux can be mediated by water availability, especially under water stress.

关键词： interaction root soil moisture temperature sensitivity water stress