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Cooperative fusion particle filter tracker

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Science China(Information Sciences) 2014年第8期57卷 142-155页

作者： WANG LingFeng yan HongPing pan ChunHong National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of Sciences College of Information and Engineering China University of Geosciences Beijing

Robust visual tracking has become an important topic in the field of computer *** multiple cues has proved to be a promising approach to visual tracking in situations where no single cue is *** this work,a new particle filter based visual tracking algorithm is *** introducing a new cooperative fusion strategy,the proposed tracker has better fault tolerance ability than the traditional *** are performed in various tracking scenes to evaluate the proposed algorithm,and the results show improved tracking accuracy.

关键词： visual tracking multi-cue fusion cooperative fusion CoFPF-tracker sum-tracker product-tracker

Effects of land use and changes in cover on the transformation and transportation of iron:A case study of the Sanjiang Plain,Northeast China

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Science China Earth Sciences 2011年第5期54卷 686-693页

作者： pan XiaoFeng yan BaiXing Yoh MUNEOKI Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Tokyo University of Agriculture and Technology Tokyo 1838509 Japan

Wetland reclamation has been ongoing in the Sanjiang Plain since the mid-1950s,which has resulted in major changes in wetlands and the agriculture ecosystem in the region that have influenced the iron output to the Sea of Okhotsk and limited the primary productivity in the North Pacific *** study was conducted to investigate the chemical forms of iron in different aquatic environments(agricultural water including groundwater,paddy water,and canal water;wetland water including marsh water,marsh streams,and main streams) with the cross-flow filtration method to reveal the transportation and transformation characteristics of iron in response to major land use *** addition,the factors affecting iron behavior in different water bodies were *** marsh water and streams,the concentrations of dissolved iron were higher due to the high organic matter contents and marsh water becoming the main iron source for river *** conversion of dissolved iron into acid-labile iron occurred during the discharge of wetland water into marsh *** primarily existed in both the >0.7 and <0.01 μm size fractions,accounting for about 58.3% and 26.4% of the total dissolved iron,*** agricultural irrigation systems,ferrous ion entered the paddy fields from groundwater,and a fraction of this ferrous iron was subsequently converted into high molecular weight and medium molecular weight iron(colloid iron) in paddy and canal ***,the concentrations of total dissolved iron decreased by 62.5% from underground to the surface due to the formation of *** this,water discharge in agriculture is still an important iron source for rivers and has the potential to supplement iron due to its higher acid-labile iron *** use and cover change and agricultural irrigation increased the iron content of surface soil,but reduced the output of iron in water ***,the concentration of total dissolved iron in water systems has be

关键词： land use and cover change marsh water marsh river agricultural water iron species Sanjiang Plain

Review and suggestions for estimating particulate organic carbon and dissolved organic carbon inventories in the ocean using remote sensing data

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Acta Oceanologica Sinica 2014年第1期33卷 1-10页

作者： pan Delu LIU Qiong BAI yan State Key Laboratory of Satellite Ocean Environment Dynamics the Second Institute of Oceanography State Oceanic Administration National Marine Environmental Forecasting Center State Oceanic Administration

Dissolved organic carbon（DOC） and particulate organic carbon（POC） are basic variables for the ocean carbon *** of the distribution and inventory of these variables is important for a better estimation and understanding of the global carbon *** to its considerable advantages in spatial and temporal coverage,remote sensing data provide estimates of DOC and POC inventories,which are able to give a synthetic view for the distribution and transportation of carbon *** estimate organic carbon inventories using remote sensing involves integration of the surface concentration and vertical profile models,and the development of these models is critical to the accuracy of ***,the distribution and control factors of DOC and POC in the ocean first are briefly summarized,and then studies of DOC and POC inventories and flux estimations are reviewed,most of which are based on field data and few of which consider the vertical distributions of POC or *** is some research on the estimation of POC inventory by remote sensing,mainly in the open ocean,in which three kinds of vertical profile models have been proposed：the uniform,exponential decay,and Gauss ***,research on remote-sensing estimation of the DOC inventory remains lacking.A synthetic review of approaches used to estimate the organic carbon inventories is offered and the future development of methods is discussed for such estimates using remote sensing data in coastal waters.

关键词： ocean carbon inventory dissolved organic carbon particulate organic carbon remote sensing

Fluid Dynamics of Flapping Insect Wing in Ground Effect

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Journal of Bionic Engineering 2014年第1期11卷 52-60页

作者： Jie Wu Chang shu Ning Zhao Weiwei yan Department of Aerodynamics Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China Department of Mechanical Engineering National University of Singapore 10 Kent Ridge Crescent 119260 Singapore College of Metrology and Measurement Engineering China Jiliang University Hangzhou 310018 P. R. China

The fluid dynamics of flapping insect wing in ground effect is investigated numerically in this study. To model the insect wing cross-section in forward-flight mode, the laminar flow over a NACA0012 airfoil animated by a combination of harmonic plunge and pitch rotation is considered. To implement the simulation, the proposed immersed boundary-lattice Boltzmann method is employed. By fixing the Reynolds number and the amplitude of motion, we systematically examine the influences of the distance between the foil and the ground and the flapping frequency on the flow behaviors. As compared to the situation out of ground effect, the forces for foil placed in close proximity to the ground show some differences. The mean drag coefficient is increased at low frequency and decreased at high frequency. Meanwhile, the mean lift coefficient is increased at both low and high frequencies and decreased at middle frequency. Moreover, an interesting phenomenon with oblate vortices due to vortex interaction with the ground is observed.

关键词： flapping insect wing ground effect drag reduction lift enhancement

Density enhancement mechanism of upwind schemes for low Mach number flows

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Acta Mechanica Sinica 2018年第3期34卷 431-445页

作者： Bo-Xi Lin Chao yan shu-Sheng Chen School of Aeronautic Science and Engineering Beihang University

Many all-speed Roe schemes have been proposed to improve performance in terms of low speeds. Among them, the F-Roe and T-D-Roe schemes have been found to get incorrect density fluctuation in low Mach flows, which is expected to be with the square of Mach number. Asymptotic analysis presents the mechanism of how the density fluctuation problem relates to the incorrect order of terms in the energy equation paU△U. It is known that changing the upwind scheme coefficients of the pressure-difference dissipation term DP and the velocity-difference dissipation term in the momentum equation DPU to the order of O （c- 1） and O（c0） can improve the level of pressure and velocity accuracy at low speeds. This paper shows that corresponding changes in energy equation can also improve the density accuracy in low speeds. We apply this modification to a recently proposed scheme, TV-MAS, to get a new scheme, TV-MAS2. Unsteady Gresho vortex flow, double shear-layer flow, low Mach number flows over the inviscid cylinder, and NACA0012 airfoil show that energy equation modification in these schemes can obtain the expected square Ma scaling of density fluctuations, which is in good agreement with corresponding asymptotic analysis. Therefore, this density correction is expected to be widely implemented into allspeed compressible flow solvers.

关键词： Energy equation Density fluctuation Roe TV-MAS Low speeds All speeds Computational fluid dynamics

Synthesis and characterization of magnetic polymer microspheres with a core-shell structure

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China Particuology 2007年第1期5卷 180-185页

作者： Ming Lu shu Bai Kun yang yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

Non-porous magnetic polymer microspheres with a core-shell structure were prepared by a novel micro-suspension polymerization technique. A stable iron oxide ferrofluid was used to supply the magnetic core, and the polymeric shell was made of glycidyl methacrylate （GMA monomer） and ethylene dimethacrylate （cross-linker）. In the preparation, polyvinyl alcohol was used as the stabilizer, and a lauryl alcohol mixture as the dispersant. The influence of various conditions such as aqueous phase volume, GMA and initiator amounts, reaction time and stirring speed on the character of the microspheres was investigated. The magnetic microspheres were then characterized briefly. The results indicate that the microspheres with active epoxy groups had a narrow size distribution range from 1 to 10 μm with a volume-weighted mean diameter of 4.5 μm. The saturation magnetization reached 19.9 emu/g with little coercivity and remanence.

关键词： Ferrofluid Micro-suspension polymerization Magnetic microspheres Particle size Magnetization

Relationship between ATPase activity and conjugated polyamines in mito-chondrial membrane from wheat seedling roots under osmotic stress

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Journal of Environmental Sciences 2004年第5期16卷 712-716页

作者： LIUHuai-pan LIUJun ZHANGyan-yan LIUYou-liang KeyLaboratoryofCropGrowthRegulation MinistryofAgricultureCollegeofLifeScienceNanjingAgricultureUniversityNanjing210095China

The effects of osmotic stress on the ATPase activity, the contents of —SH group and conjugated polyamines in mitochondrial membrane from wheat seedling [Triticum aestivum L. cv. Yumai No.18(drought-tolerant) and cv. Yumai No.9(drought-sensitive)] roots were investigated. The results showed that ATPase activity and —SH group content decreased with polyethylene glycol(PEG) 6000(-0.55 MPa) treatment for 7 d, in concert with the decrease of the ratio of noncovalently conjugated spermidine(NCC-Spd)/noncovalently conjugated putrescine(NCC-Put) and increase of the covalently conjugated putrescine(CC-Put). Osmotic stress injury to yangmai No.9 seedlings was alleviated greatly with 1 mmol/L exogenous spermidine(Spd), in concert with marked increases of the ratio of NCC-Spd/NCC-Put, —SH group contents and ATPase activity in mitochondrial membrane. Under osmotic stress, the concomitant treatment of Yumai No.18 seedlings with methylglyoxyl bis(guanylhydrazone) (MGBG), an inhibitor of S-adenosyl methionine decarboxylase(SAMDC), and phenanthrolin (o-Phen), an inhibitor of transglutaminase(TGase), caused a significant decrease of the ratio of NCC-Spd / NCC-Put, CC-Put contents, respectively, in concert with the marked decreases of ATPase activity, —SH group content and its tolerance to osmotic stress. All the results above suggested that osmotic stress tolerance of wheat seedlings was associated with the ATPase activity, the contents of —SH group, NCC-Spd and CC-Put in mitochondrial membrane.

关键词： ATPase conjugated polyamines mitochondria osmotic stress wheat(Triticum aestivum L.)

Mercury transportation in soil via using gypsum from flue gas desulfurization unit in coal-fired power plant

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Journal of Environmental Sciences 2013年第9期25卷 1858-1864页

作者： Kelin Wang William Orndorff yan Cao Weiping pan Institute for Combustion Science and Environmental Technology Western Kentucky University

The mercury flux in soils was investigated, which were amended by gypsums from flue gas desulphurization （FGD） units of coal- fired power plants. Studies have been carried out in confined greenhouses using FGD gypsum treated soils. Major research focus is uptakes of mercury by plants, and emission of mercury into the atmosphere under varying application rates of FGD gypsum, simulating rainfall irrigations, soils, and plants types. Higher FGD gypsum application rates generally led to higher mercury concentrations in the soils, the increased mercury emissions into the atmosphere, and the increased mercury contents in plants （especially in roots and leaves）. Soil properties and plant species can play important roles in mercury transports. Some plants, such as tall fescue, were able to prevent mercury from atmospheric emission and infiltration in the soil. Mercury concentration in the stem of plants was found to be increased and then leveled off upon increasing FGD gypsum application. However, mercury in roots and leaves was generally increased upon increasing FGD gypsum application rates. Some mercury was likely absorbed by leaves of plants from emitted mercury in the atmosphere.

关键词： flue gas desulphurization gypsums soils mercury emissions mercury uptakes mercury infiltration greenhouse tests

An acetic acid refluxing-electrochemistry combined strategy to activate supported-platinum electrocatalysts

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Particuology 2017年第1期15卷 111-117页

作者： yan Feng Jinding pan Hui Liu Jun yang State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of ChineseAcademy of Sciences No. 19A Yuquan Road Beijing 100049 China Center for Mesoscience Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China

Surfactant removal from the surface of platinum-based nanoparticles prepared using solution-based methods is a prerequisite to realize their high catalytic performance for electrochemical reactions. Herein, we report an effective approach combining acetic acid refluxing with an electrochemical process for the removal of amine- or thiol-based capping agents from the surface of supported-platinum nanoparticles. This strategy involves surfactant protonation by refluxing the supported-platinum particles in acetic acid followed by surfactant removal by subsequent electrochemical treatment at high potential. We demon- strate that this combined activation process is essential to enhance platinum particle performance in catalyzing direct methanol fuel cell reactions, including methanol oxidation and oxygen reduction reac- tions. The studies in this work show promise in electrocatalysis applications of solution-based materials synthesis.

关键词： Platinum Nanoparticle Methanol oxidation reaction Oxygen reduction reaction Electrocatalysis