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Fractional-Order Control for a Novel Chaotic System Without equilibrium

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Ieee/CAA Journal of Automatica Sinica 2019年第4期6卷 1000-1009页

作者： Shuyi Shao mou Chen the College of Automation engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Ieee

The control problem is discussed for a chaotic system without equilibrium in this *** the basis of the linear mathematical model of the two-wheeled self-balancing robot,a novel chaotic system which has no equilibrium is *** basic dynamical properties of this new system are studied via Lyapunov exponents and Poincar′e *** further demonstrate the physical realizability of the presented novel chaotic system,a chaotic circuit is *** using fractional-order operators,a controller is designed based on the state-feedback *** to the Gronwall inequality,Laplace transform and Mittag-Leffler function,a new control scheme is explored for the whole closed-loop *** the developed control scheme,the state variables of the closed-loop system are controlled to stabilize them to ***,the numerical simulation results of the chaotic system with equilibrium and without equilibrium illustrate the effectiveness of the proposed control scheme.

关键词： Chaotic system circuit implementation fractional-order stabilization

Dynamic Flight Stability of a Model Hoverfly in Inclined-Stroke-Plane Hovering

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Journal of Bionic engineering 2012年第3期9卷 294-303页

作者： Xiaolei mou Mao Sun Key Laboratory of Fluid Mechanics(Ministry of education China)Beihang UniversityBeijing 100191P.R.China

Most hovering insects flap their wings in a horizontal plane, called ＇normal hovering＇. But some of the best hoverers, e.g. true hoverflies, hover with an inclined stroke plane. In the present paper, the longitudinal dynamic flight stability of a model hoverfly in inclined-stroke-plane hovering was studied. Computational fluid dynamics was used to compute the aerodynamic derivatives and the eigenvalue and eigenvector analysis was used to solve the equations of motion. The primary findings are as follows. （1） For inclined-stroke-plane hovering, the same three natural modes of motion as those for normal hovering were identified： one unstable oscillatory mode, one stable fast subsidence mode, and one stable slow subsidence mode. The unstable oscillatory mode and the fast subsidence mode mainly have horizontal translation and pitch rotation, and the slow subsidence mode mainly has vertical translation. （2） Because of the existence of the unstable oscillatory mode, inclined-stroke-plane hov- ering flight is not stable. （3） Although there are large differences in stroke plane and body orientations between the in- clined-stroke-plane hovering and normal hovering, the relative position between the mean center of pressure and center of mass for these two cases is not very different, resulting in similar stability derivatives, hence similar dynamic stability properties for these two types of hovering.

关键词： insect dynamic flight stability inclined-stroke-plane hovering natural modes of motion

An improved wind quality control for the China-France Oceanography Satellite (CFOSAT) scatterometer

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Acta Oceanologica Sinica 2024年第5期43卷 100-109页

作者： Xiaoheng mou Wenming Lin School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Key Laboratory of Space Ocean Remote Sensing and Application Ministry of Natural ResourcesBeijing 100081China

Quality control(QC)is an essential procedure in scatterometer wind retrieval,which is used to distinguish good-quality data from poor-quality wind vector cells(WVCs)for the sake of wind *** current wind processor of the China-France Oceanography Satellite(CFOSAT)scatterometer(CSCAT)adopts a maximum likelihood estimator(MLe)-based QC method to filter WVCs affected by geophysical noise,such as rainfall and wind *** the first Ku-band rotating fan-beam scatterometer,CSCAT can acquire up to 16 observations over a single WVC,giving abundant information with diverse incidence/azimuth angles,as such its MLe statistical characteristics may be different from the previous *** this study,several QC indicators,including MLe,its spatially averaged value(MLe_(m)),and the singularity exponents(Se),are analyzed using the collocated Global Precipitation Mission rainfall data as well as buoy data,to compare their sensitivity to rainfall and wind *** results show that wind error characteristics of CSCAT under different QC methods are similar to those of other Ku-band scatterometers,i.e.,Se is more suitable than other parameters for the wind QC at outer-swath and nadir regions,while MLe_(m) is the best QC indicator for the sweet region ***,Se is much more favorable than others at high wind *** combining different indicators,an improved QC method is developed for *** validation with the collocated buoy data shows that it accepts more WVCs,and in turn,improves the quality control of CSCAT wind data.

关键词： China-France Oceanography Satellite(CFOSAT) scatterometer winds quality control(QC) singularity exponent(Se)

Novel virulence factor dupA of Helicobacter pylori as an important risk determinant for disease manifestation:An overview

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World Journal of Gastroenterology 2020年第32期26卷 4739-4752页

作者： Jawed Alam Avijit Sarkar Bipul Chandra Karmakar mou Ganguly Sangita paul Asish K Mukhopadhyay Division of Infectious Diseases Institute of Life ScienceBhubaneswar 751023India Division of Bacteriology ICMR-National Institute of Cholera and Enteric DiseasesKolkata 700010India

Helicobacter pylori(***)is a microaerophilic,Gram-negative,human gastric pathogen found usually in the mucous lining of *** infects more than 50%of the world’s population and leads to gastroduodenal *** outcome of disease depends on mainly three factors:Host genetics,environment and bacterial *** these,bacterial virulence factors such as cagA,vacA are well known for their role in disease ***,based on the global epidemiological results,none of the bacterial virulence(gene)factors was found to be associated with particular diseases like duodenal ulcer(DU)in all ***,substantial importance has been provided for research in strain-specific genes outside the cag pathogenicity island,especially genes located within the plasticity *** found within the plasticity regions was first demonstrated in 2005 and was proposed for duodenal ulcer development and reduced risk of gastric cancer in certain geographical *** to the discrepancies in report from different parts of the world in DU development related to *** virulence factor,dupA became an interesting area of research in elucidating the role of this gene in the disease *** this review,we shed light on the detailed information available on the polymorphisms in dupA and their clinical *** have critically appraised several pertinent studies on dupA and discussed their merits and *** review also highlights dupA gene as an important biomarker for DU in certain populations.

关键词： Helicobacter pylori Plasticity region Duodenal ulcer Gastric cancer dupA gene

Light-Programmable Assemblies of Isotropic Micromotors

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Research 2022年第4期2022卷 481-492页

作者： Shengping Che Jianhua Zhang Fangzhi mou Xia Guo Joshua e.Kauffman Ayusman Sen Jianguo Guan State Key Laboratory of Advanced Technology for Materials Synthesis and Processing International School of Materials Science and EngineeringWuhan University of Technology122Luoshi RoadWuhan 430070China Department of Chemistry The Pennsylvania State UniversityUniversity ParkPA16802USA

“Life-like”nonequilibrium assemblies are of increasing significance,but suffering from limited steerability as they are generally based on micro/nanomotors with inherent asymmetry in chemical composition or geometry,of which the vigorous random Brownian rotations disturb the local ***,we demonstrate that isotropic photocatalytic micromotors,due to the persistent phoretic flow from the lluminated to shadowed side rrespective of their Brownian rotations,experience lightprogrammable local interactions(reversibly from atraction to repulsion and/or alignment)depending on the direction of the incident ***,they can be organized into a variety of tunable nonequilibrium assemblies,such as apolar solids(i.e.,immobile colloidal crystal),polar liquids(ie.,phototactic colloidal stream),and polar solids(i.e.,phototactic colloidal crystal),which can further be“cut”into a predesigned pattern by utilizing the switching motor-motor interactions at superimposedlight *** work facilitates the development of active matters and motile functional microdevices.

关键词： Brownian rotation nonequilibrium

Characteristics of soil water retention curve at macro-scale

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Science China(Technological Sciences) 2009年第10期52卷 2990-2996页

作者： TIAN FuQiang mou LiQin HU HePing State Key Laboratory of Hydro-Science and engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China

Scale adaptable hydrological models have attracted more and more attentions in the hydrological modeling research community, and the constitutive relationship at the macro-scale is one of the most important issues, upon which there are not enough research activities yet. Taking the constitutive relationships of soil water movement--soil water retention curve (SWRC) as an example, this study extends the definition of SWRC at the micro-scale to that at the macro-scale, and aided by Monte Carlo method we demonstrate that soil property and the spatial distribution of soil moisture will affect the features of SWRC greatly. Furthermore, we assume that the spatial distribution of soil moisture is the result of self-organization of climate, soil, ground water and soil water movement under the specific boundary conditions, and we also carry out numerical experiments of soil water movement at the vertical direction in order to explore the relationship between SWRC at the macro-scale and the combinations of climate, soil, and groundwater. The results show that SWRCs at the macro-scale and micro-scale presents totally different features, e.g., the essential hysteresis phenomenon which is exaggerated with increasing aridity index and rising groundwater table. Soil property plays an important role in the shape of SWRC which will even lead to a rectangular shape under drier conditions, and power function form of SWRC widely adopted in hydrological model might be revised for most situations at the macro-scale.

关键词： scale issue constitutive relationship soil water retention curve Richards equation

Relaxor behavior and superior ferroelectricity of Y_(2)O_(3)-doped(Ba_(0.98)Ca_(0.02))(Ti_(0.94)Sn_(0.04)Zr_(0.02))O_(3) lead-free ceramics

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Journal of Rare earths 2022年第6期40卷 942-951,I0004页

作者： Sifan Wang Qibin Liu enpei Cai Fanghui mou An Xue College of Material and Metallurgy Guizhou UniversityGuiyang 550025China Key Laboratory for Modern Manufacturing Technology of educational Ministry Guiyang 550025China

To upgrade the electric properties of lead-free piezoceramics,(1-x)(Ba_(0.98)Ca_(0.02)Ti_(0.94)Sn_(0.04)Zr_(0.02))O_(3)-xY_(2)O_(3)(abbreviated as(1-x)BCTSZ-xY,x=0 mol%,0.02 mol%,0.04 mol%,0.06 mol%,0.08 mol%and 0.1 mol%)ceramics were successfully synthesized by traditional solid-state sintering *** phase structure and microstructure of ceramics were investigated by X-ray diffraction(XRD),scanning electron microscopy(SeM)and piezoresponse force microscopyeramics(PFM).The electric properties of ceramics were researched through piezoelectric,dielectric and ferroelectric test *** results show that all samples have pure perovskite structure and favorable electric *** optimal electric properties which especially include superior ferroelectric properties are gained when Y_(2)O_(3)content is 0.06 mol%(d_(33)=419 pC/N,k_(p)=52%,T_(c)=89.5℃,ε_(r)=26900,tanδ=2.86%,P_(r)=14.41μC/cm^(2),ec=1.8 kV/cm).Moreover,the temperature-dependent dielectricity of samples shows apparent relaxor behavior under different *** Curie-Weiss law further proves that all samples are typical relaxor ferroelectrics,and the relaxor degree of samples decreases with increase of Y_(2)O_(3)*** conclusion,Y_(2)O_(3)plays a significant role in enhancing electric properties of BCTSZ ceramics.

关键词： Lead-free ceramics Y2O_(3)doping Relaxor behavior Ferroelectric properties Rare earths

Processes Controlling the Carbonate Chemistry of Surface Seawater Along the 150°e Transect in the Northwest Pacific Ocean

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Journal of Ocean University of China 2022年第6期21卷 1529-1537页

作者： mou Liang ZHANG Honghai CHeN Zhaohui HU Yubin Institute of Marine Science and Technology Shandong UniversityQingdao 266237China Frontiers Science Center for Deep Ocean Multispheres and earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100China

The problem of ocean acidification caused by the increase of atmospheric carbon dioxide concentration is becoming increasingly *** observation in the northwest Pacific Ocean was carried out along the 150°e transect in November *** distribution characteristics and influencing factors of the surface seawater carbonate chemistry,including dissolved inorganic carbon(DIC),total alkalinity(TA),pH,partial pressure of carbon dioxide(pCO_(2))and aragonite saturation state(Ω_(arag))were *** and TA ranged from 1915 to 2014μmol kg^(−1)and 2243 to 2291μmol kg^(−1),respectively;DIC in general decreased with decreasing latitude,but TA had no clear latitudinal ***_(2)values increased with the decrease of latitude and were all below the atmospheric pCO_(2)level,ranging from 332 to 387μ*** on the total hydrogen ion concentration scale(pH_(T))decreased with the decrease of latitude in the range of 8.044–8.110,whileΩ_(arag) increased with the decrease of latitude in the range of 2.61–3.88,suggesting that the spatial distributions of pH_(T) andΩ_(arag) were out of *** with the present,the predicted values of pH_(T) and Ω_(arag) by the end of this century would decrease remarkedly;larger declines were found in the higher pH_(T) and Ω_(arag) regions,resulting in the differences along the meridional gradient becoming smaller for bothpH_(T) and Ω_(arag).

关键词： ocean acidification carbonate system aragonite saturation state seawater pH Pacific Ocean

Carbon nanomaterial addition changes soil nematode community in a tall fescue mesocosm

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Pedosphere 2022年第5期32卷 777-784页

作者： Shulan ZHAO Xue BAI Mengdi mou Lian DUO Tianjin Key Laboratory of Animal and Plant Resistance College of Life SciencesTianjin Normal UniversityTianjin 300387(China)

Carbon nanomaterials have been widely used in industry and inevitably enter the ***,there is little information about their influence on the abundance and diversity of soil nematode *** evaluated the impact of three kinds of carbon nanomaterials(graphene,graphene oxide,and carbon nanotubes)on the abundance and diversity of soil nematodes after growing tall fescue for 130 d using a laboratory pot experiment.A total of 29 genera of nematodes were identified in all the *** nanomaterials significantly increased the abundance of total nematodes and plant *** presence of graphene and graphene oxide increased the numbers of bacterivores,and graphene benefited *** total nematode abundance was1.9-2.9 times greater in the carbon nanomaterial treatments than in the control with no carbon nanomaterial ***,graphene oxide and carbon nanotubes decreased the values of nematode community parameters,e.g.,diversity,species richness,and structure *** with the control,the addition of graphene resulted in a community with a higher plant-parasitic index(i.e.,the maturity index of the plant-parasitic nematodes).Overall,our findings highlight that the addition of carbon nanomaterials has a negative influence on the composition and diversity of the nematode community,simplifying the community structure.

关键词： carbon nanotubes community diversity community structure graphene graphene oxide nematode abundance plant-parasitic index species richness