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Application analysis of empirical mode decomposition and phase space reconstruction in dam time-varying characteristic

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Science china(Technological Sciences) 2010年第6期53卷 1711-1716页

作者： ZHANG ZhiJun1,2,3,GU ChongShi1,2,BAO TengFei1,2,ZHANG Lan1,2 & YU Hong1,2 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering,Hohai university,nanjing 210098,china 2 National engineering Research Center of Water Resources Efficient Utilization and engineering Safety,Hohai university,nanjing 210098,china 3 Department of civil,Environmental and Geomatic engineering,Swiss Federal Institute of technology,Zurich 8093,Switzerland State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering Hohai University Nanjing China National engineering Research Center of Water Resources Efficient Utilization and engineering Safety Hohai University Nanjing China Department of civil Environmental and Geomatic Engineering Swiss Federal Institute of Technology Zurich Switzerland

In view of some courses of the time-varying characteristics processing in the analysis of dam deformation,the paper proposes a new method to analyze the dam time-varying characteristic based on the empirical mode decomposition and phase space reconstruction *** of all,to reduce the influences on the traditional statistical model from human factors and assure the analysis accuracy,response variables of the time-varying characteristic are obtained by the way of the empirical mode decomposition;and then,a phase plane of those variables is reconstructed to investigate their processing *** methods have already been applied to an actual project and the results showed that data interpretation with the assists of empirical mode decomposition and phase space reconstruction is effective in analyzing the perturbations of response variables,explicit in reflecting the entire development process,and valid for obtaining the evolution rules of the time-varying *** methodology is a powerful technical support for people to further master the rules of dam operation.

关键词： dam safety monitoring dam time-varying characteristic empirical mode decomposition phase space reconstruction

Adsorption separation of carbon dioxide,methane,and nitrogen on Hβand Na-exchangedβ-zeolite

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Journal of Energy Chemistry 2008年第4期17卷 391-396页

作者： Xiaoliang Xu Xingxiang Zhao Linbing Sun Xiaoqin Liu State Key Laboratory of Materials-Oriented Chemical engineering,college of Chemistry and Chemical engineering,nanjing university of technology,nanjing 210009,Jiangsu,china State Key Laboratory of Materials-Oriented Chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 Jiangsu China

Adsorption isotherms of carbon dioxide(CO),methane(CH),and nitrogen(N)on Hβand sodium exchangedβ-zeolite(Naβ)were volumetrically measured at 273 and 303 *** results show that all isotherms were of Brunauer typeⅠand well correlated with Langmuir-Freundlich *** sodium ions exchange,the adsorption amounts of three adsorbates increased,while the increase magnitude of COadsorption capacity was much higher than that of CHand *** selectivities of COover CHand COover Nenhanced after sodium ***,the initial heat of adsorption data implied a stronger interaction of COmolecules with Na~+ ions in Naβ.These results can be attributed to the larger electrostatic interaction of COwith extraframework cations in ***,Naβshowed a decrease in the selectivity of CHover N,which can be ascribed to the moderate affinity of Nwith Naβ.The variation of isosteric heats of adsorption as a function of loading indicates that the adsorption of COin Naβpresents an energetically heterogeneous *** the contrary,the adsorption of CHwas found to be essentially homogeneous,which suggests the dispersion interaction between CHand lattice oxygen atoms,and such interaction does not depend on the exchangeable cations of zeolite.

关键词： CO2 CH4 N2 adsorption separation Hβ Naβ

CHANGES OF PAN EVAPORATION IN THE UPPER REACH OF THE YANGTZE RIVER

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Journal of Hydrodynamics 2011年第4期23卷 503-509页

作者： RONG Yan-shu WANG Wen JIANG Hai-yan college of Hydrology and Water Resources Hohai University Nanjing 210098 China State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering Hohai University Nanjing 210098 China

The upper reach of the Yangtze River, 4 511 km long from west to east, contains a great amount of water resources of the Yangtze River Basin. This article studies the characteristics of the pan evaporation, the related meteorological variables, and their effects on the pan evaporation, based on the data of the daily pan evaporation （1980-2008） and other meteorological variables （1961-2008）. The results show that the linear trend of the pan evaporation has remarkable regional features, i.e., the decrease trend in the southwest and the increase trend in the northeast of the investigated region, and the Yangtze River is approximately the boundary of these trends. The meteorological variables have different effects on the pan evaporation depending on the fact that they are in the category the thermal variables or the dynamic variables. The thermal meteorological variables （i.e., air temperature, diurnal temperature range, and sunshine duration） have positive partial correlations with the pan evaporation, while the dynamic ones （air pressure, rainfall, and relateive humidity） have negative correlations with the pan evaporation. The correlation of the wind speed remains to be investigated.

关键词： linear time trend meteorological variable pan evaporation partial correlation Yangtze River

Bathynotus:A key trilobite taxon for global stratigraphic boundary correlation between Cambrian Series 2 and Cambrian Series 3

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Progress in Natural Science:Materials International 2009年第1期19卷 99-105页

作者： Jin Peng a,b,Yuanlong Zhao b,Jinliang Yuan c,Lu Yao b,Hong Yang b a Department of Earth Sciences,nanjing university,nanjing 210093,china b college of Resource and Environmental engineering,Guizhou university(Caijiaguan Campus),Guiyang 550003,china c nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,nanjing 210008,china Department of Earth Sciences Nanjing University Nanjing 210093 China college of Resource and Environmental engineering Guizhou University (Caijiaguan Campus) Guiyang 550003 China nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Cambrian trilobite Bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed ***,its 12th and 13th pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural *** genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South china,the Tarim Basin of china,and *** occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early ***,we recognize three species of Bathynotus from china,including *** which is widespread around the *** six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are *** exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2 and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2 and Cambrian Series *** late appearance datum(LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2 and Cambrian Series 3.

关键词： Bathynotus Age Cambrian Series 2 Boundary Correlation

Pyridine-H_5PMo_(10)V_2O_(40) hybrid catalysts for liquid-phase hydroxylation of benzene to phenol with molecular oxygen

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Science china Chemistry 2009年第8期52卷 1264-1269页

作者： GE HanQing1,LENG Yan1,ZHANG FuMin1,PIAO JiaRui2,ZHOU ChangJiang1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented Chemical engineering,college of Chemistry and Chemical engineering,nanjing university of technology,nanjing 210009,china 2 Petrochemical Research Institute,Petrochina Company Ltd.,Beijing 100083,china State Key Laboratory of Materials-Oriented Chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing China Petrochemical Research Institute PetroChina Company Ltd. Beijing China

Pyridine(Py)-modified Keggin-type vanadium-substituted heteropoly acids(PynPMo10V2O40,n=1 to 5) were prepared by a precipitation method as organic/inorganic hybrid catalysts for direct hydroxylation of benzene to phenol in a pressured batch reactor and their structures were detected by *** various catalysts,Py3PMo10V2O40 exhibits the highest catalytic activity(yield of phenol,11.5%),without observing the formation of catechol,hydroquinone and benzoquinone in the reaction with 80 vol% aqueous acetic acid,molecular oxygen and ascorbic acid used as the solvent,oxidant and reducing reagent,*** of reaction temperature,reaction time,oxygen pressure,amount of ascorbic acid and catalyst on yield of phenol were investigated to obtain the optimal reaction conditions for phenol *** can greatly promote the catalytic activity of the Py-free catalyst(H5PMo10V2O40),mostly because the organic π electrons in the hybrid catalyst may extend their conjugation to the inorganic framework of heteropoly acid and dramatically modify the redox properties,at the same time,pyridine adsorbed on heteropoly acids can promote the effect of "pseudo-liquid phase",thus accounting for the enhancement of phenol yield.

关键词： hydroxylation benzene organic/inorganic hybrid catalyst phenol heteropoly acid pyridine

Decisive influence of the ionization strength of cosmic rays on the cavitation characteristics of pure water

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Science china(Technological Sciences) 2009年第6期52卷 1804-1808页

作者： CHANG JinShi college of Water Conservancy & civil engineering,china Agricultural university,Beijing 100083,china college of Water Conservancy & civil engineering China Agricultural University Beijing China

The experiment result in this article shows that the initial and critical cavitation pressure of pure water are both increasing along with the increase of height above sea level,and the ionization strength of cosmic rays in the lower aerosphere is the crucial factor which influences the cavitation pressure of pure *** author concludes the relationship between the cavitaion pressure of pure water and the height above sea ***,air particles in water caused by the radiation of cosmic rays can exist in the water for a long time and will not escape.

关键词： initial cavitaiton pressure critical cavitation pressure ionization strength of cosmic rays height above sea level

SONIC SPEED AND SHOCK WAVE IN HIGH VELOCITY AERATED FLOWS FROM HIGH HEAD DISCHARGE STRUCTURES

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Journal of Hydrodynamics 2003年第4期15卷 98-103页

作者： Dong Zhi-yong Schood of civil and Architectural engineering, Zhejiang university of technology, Hangzhou 310014, china Sch. of civil and Arch. Eng. Zhejiang Univ. of Technol. Hangzhou 310014 China

The compressible characteristics in aerated flows at the high velocity ofabout 50m/s were analyzed. Based on the theory of compressible the relations between the sonic speedand shock wave in high-velocity aerated flow were theoretically deduced. And comparisons withmeasured data were made. The theoretical and experimental results show the sonic speed in aeratedflow is merely of the order of several-dozen meters per second, and its minimum value is only 20m/s, which is far much less than that in water or air alone. So high subsonic flow, supersonic flowand transonic flow as well as compression wave, shock wave and expansion wave similarly toaerodnamics may be produced in high velocity aerated flow at the speed of the order of 50m/s. Hencethe influences of these compressible characteristics on high head discharge structures can not beneglected, especially on super high dams over 200m high.

关键词： sonic speed shock wave aerated flow super high dam compressibility

A two-dimensional study on natural convection and heat transfer in the enclosure with heat transfer and radiation coupled in natural convection

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Science china(Technological Sciences) 2010年第4期53卷 991-999页

作者： ZHAN NaiYan1,2,YANG Mo1 & XU PeiWei2 1 college of Power engineering,university of Shanghai for Science and technology,Shanghiai 200093,china 2 Department of Environmental engineering,Jilin Architectural and civil engineering Institute,Changchun 130021,china college of Power engineering University of Shanghai for Science and Technology Shanghiai China Department of Environmental engineering Jilin Architectural and Civil Engineering Institute Changchun China

Numerical investigation using SIMPLE algorithm with QUICK scheme for natural convection and heat transfer in the enclosure bounded by a solid wall and with heat transfer and radiation coupled in natural convection has been *** various parameters are:Rayleigh number(from 103 to 105),dimensionless conductivity of bounding wall(from 0 to 100),dimensionless wall thickness(from 0 to 0.6) and radiation emissivity of all surfaces(from 0 to 1).The results suggest that flow and heat transfer are influenced by *** is a dominant action on flow and heat *** increase of the thermal conductivity of wall,flow and heat transfer turn *** temperature distribution changes *** the thermal conductivity of wall is over a certain critical number,the increasing trend of flow and heat transfer may *** increase of enclosure wall thickness,flow and heat transfer turn *** the enclosure wall thickness is over a certain critical number,the flow and heat transfer will turn slow.

关键词： conduction natural convection radiation couple numerical simulation

Unscented Kalman filtering in the additive noise case

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Science china(Technological Sciences) 2010年第11期53卷 929-941页

作者： LIU Ye1,YU AnXi1,ZHU JuBo2 & LIANG DianNong1 1 college of Electronic Science and engineering,National university of Defense technology,Changsha 410073,china 2 Science college,National university of Defense technology,Changsha 410073,china college of Electronic Science and engineering National University of Defense Technology Changsha China Science college National University of Defense Technology Changsha China

The unscented Kalman filter(UKF) has four implementations in the additive noise case,according to whether the state is augmented with noise vectors and whether a new set of sigma points is redrawn from the predicted state(which is so-called resampling) for the observation *** paper concerns the differences of performances for those implementations,such as accuracy,adaptability,computational complexity,*** conditionally equivalent relationships between the augmented and non-augmented unscented transforms(UTs) are proved for several sampling strategies that are commonly ***,we find that the augmented and non-augmented UKFs have the same filter results with the additive measurement noise,but only have the same state predictions with the additive process *** is not believed to be necessary in some ***,we find out that resampling can be helpful for an adaptive Kalman *** will improve the convergence and accuracy of the filter when the large scale state modeling bias or unknown maneuvers ***,some universal designing principles for a practical UKF are given as follows:1) for the additive observation noise case,it's better to use the non-augmented UKF;2) for the additive process noise case,when the small state modeling bias or maneuvers are involved,the non-resampling algorithms with state whether augmented or not are candidates for filters;3) the resampling and non-augmented algorithm is the only choice while the large state modeling bias or maneuvers are latent.

关键词： unscented Kalman filter additive noise unscented transformation augmented redraw sigma points adaptive