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Convex hull of set in thick part of Teichmller space

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Science China Mathematics 2014年第9期57卷 1799-1810页

作者： LIU LiXin SHIGA Hiroshige sun ZongLiang Department of Mathematics Sun Yat-sen University Department of Mathematics Tokyo Institute of Technology Department of Mathematics Shenzhen University

Let X be a non-elementary Riemann surface of type(g,n),where g is the number of genus and n is the number of punctures with 3g-3+n>*** T(X)be the Teichmller space of *** constructing a certain subset E of T(X),we show that the convex hull of E with respect to the Teichmller metric,the Carathodory metric and the Weil-Petersson metric is not in any thick part of the Teichmler space,*** implies that convex hulls of thick part of Teichmller space with respect to these metrics are not always in thick part of Teichmller space,as well as the facts that thick part of Teichmller space is not always convex with respect to these metrics.

关键词： Carathéodory metric Teichmuller metric Weil-Petersson metric convex hull Dehn twist

Modeling and analysis of pelletization process based on a multi-hole pelletizing device

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International Journal of Agricultural and Biological Engineering 2019年第1期12卷 17-23页

作者： Qinghai Jiang Kai Wu Yu sun School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

A multi-hole pelletizing device(MPD)was proposed to simulate the granular extrusion process of animal feed due to its cheap,fast,and controllable *** compression mechanism was analyzed and discussed according to the compression force-time *** study applied response surface methodology(RSM)with a central composite design(CCD)to develop predictive models for the compression force Fout and the pellet properties which includes pellet densityρp,pellet moisture content Mcp,and pellet tensile strength Dp based on the *** effects of feedstock moisture content Mcf(10%-18%w.b.),feedstock particle size Sf(8 meshes-24 meshes),die temperature Td(70°C-110°C)and compression speed Vc(5 mm/min to 25 mm/min)were *** surface models developed for the compression force and pellet properties have adequately described the pelleting process(R^(2)>0.95).The results showed the significant effects of all factors and most of the squared and interaction terms on the compression force and pellet physical *** can be concluded from the present study that moisture content and die temperature,followed by compression speed and feedstock particle size are the interacting process factors influencing compression force and pellet properties.

关键词： animal feed pelletization modeling compression force response surface methodology analysis of variance

Computational Modeling of Optical Response from Excitons in a Nano OpticalMedium

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Communications in Computational Physics 2008年第10期4卷 1051-1068页

作者： Yuanchang sun Hiroshi Ajiki Gang Bao Department of Mathematics Michigan State UniversityEast LansingMI 48824USA Graduate School of Engineering Science Osaka University1-3 MachikaneyamaToyonaka 560-8531Japan

Consider a time-harmonic electromagnetic plane wave incident on a microscopic *** the medium,at any given frequencyω,more than one polariton mode can arise with the same frequency but different wavenumbers due to the presence of *** Maxwell’s boundary conditions,additional boundary conditions are required to handle the multi-mode *** order to model the confinement effect of excitons in the microscopic semiconductor,Maxwell’s equations and the Schr¨odinger equation are coupled to characterize the polarization in terms of the quantum *** the weak confinement regime,we derive a perturbed dispersive dielectric constant by taking the exciton effect into *** also analyze and compute the optical linear response of the exciton in both one-dimensional and two-dimensional *** the one-dimensional case,the existence and uniqueness of the analytical solution are established in the resonance region.A finite difference method is developed to compute the two dimensional confinement.

关键词： Nano optics exciton modeling

Adaptive Iterative Learning Control for a Class of Nonlinear Time-varying Systems with Unknown Delays and Input Dead-zone

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IEEE/CAA Journal of Automatica Sinica 2014年第3期1卷 302-314页

作者： Jianming Wei Yunan Hu Meimei sun the Department of Control Engineering Naval Aeronautical Engineering Institute

This paper presents an adaptive iterative learning control(AILC) scheme for a class of nonlinear systems with unknown time-varying delays and unknown input dead-zone.A novel nonlinear form of dead-zone nonlinearity is *** assumption of identical initial condition for iterative learning control(ILC) is removed by introducing boundary layer *** uncertainties with time-varying delays are compensated for by using appropriate Lyapunov-Krasovskii functional and Young’s *** basis function neural networks are used to model the time-varying *** hyperbolic tangent function is employed to avoid the problem of *** to the property of hyperbolic tangent function,the system output is proved to converge to a small neighborhood of the desired trajectory by constructing Lyapunov-like composite energy function(CEF) in two cases,while keeping all the closedloop signals ***,a simulation example is presented to verify the effectiveness of the proposed approach.

关键词： Adaptive systems Delays Iterative methods Learning (artificial intelligence) Nonlinear systems Time-varying systems Trajectory Adaptive iterative learning control nonlinear time-varying systems unknown input dead-zone unknown time-varying delays Nonlinear time-varying system Radial basis function networks Iterative learning control output(systems) Nonlinear systems trajectory delay time-varying systems iterative methods Dead band hyperbolic tangent Adaptive systems

Polysaccharides from Agrocybe cylindracea residue alleviate type 2-diabetes-induced liver and colon injuries by p38 MAPK signaling pathway

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Food Bioscience 2022年第3期47卷 858-872页

作者： Wenxue sun Yaohan Zhang Le Jia College of Life Science Shandong Agricultural UniversityTaian271018PR China

In this experiment,we investigated the possible mechanism of polysaccharides from Agrocybe cylindracea residue (PACR) on ameliorating the type-2-diabetes-induced liver and colon *** experiments have proved that PACR could reduce the oxidative damage and inflammatory ***,the PACR could restore lipid levels,decrease the level of liver and colon lesions in injured mice,and finally play a role in protecting liver and *** results showed that PACR could be used as a supplement to decrease blood glucose and relieve T2DM and reduce oxidative stress and inflammatory response by inhibiting the activation of p38 MAPK signaling pathway.

关键词： Type 2 diabetes Polysaccharides p38 MAPK signal pathways

Anomalous temperature dependent photoluminescence properties of CdS_xSe_(1-x) quantum dots

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Science China(Physics,Mechanics & Astronomy) 2010年第10期53卷 1842-1846页

作者： YU DongQi CHEN Xi ZHANG HeQiu HU LiZhong sun JingChang QIAO ShuangShuang sun KaiTong ZHU JinXia School of Physics and Electronic Technology Liaoning Normal UniversityDalian 116029China School of Physics and Optoelectronic Technology Dalian University of TechnologyDalian 116024China

CdSxSe1-x quantum dots were fabricated by a simple spin-coating heat volatilization method on InP *** dependent photoluminescence of CdSxSe1-x quantum dots was carried out in a range of 10-300 *** integrated photoluminescence intensity revealed an anomalous behavior with increasing temperature in the range of 180-200 *** band gap energy showed a redshift of 61.34 meV when the temperature increased from 10 to 300 *** component ratio of S to Se in the CdSxSe1-x quantum dots was valued by both the X-ray diffraction data and photoluminescence peak energy at room temperature according to Vegard ***,the parameters of the Varshni relation for CdS0.9Se0.1 materials were also obtained using photoluminescence peak energy as a function of temperature and the best-fit curve:α=(3.5 ± 0.1)10-4 eV/K,and β=210 ± 10 K (close to the Debye temperature θD of the material).

关键词： CdSxSe1-x quantum dots temperature dependent photoluminescence

Line Fault Detection of DC Distribution Networks Using the Artificial Neural Network

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Energy Engineering 2023年第7期120卷 1667-1683页

作者： Xunyou Zhang Chuanyang Liu Zuo sun Country College of Mechanical and Electrical Engineering Chizhou UniversityChizhou247000China School of Electrical Engineering Southeast UniversityNanjing210096China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing211106China

ADC distribution network is an effective solution for increasing renewable energy utilization with distinct benefits,such as high efficiency and easy ***,a sudden increase in the current after the occurrence of faults in the network may adversely affect network *** study proposes an artificial neural network(ANN)-based fault detection and protection method for DC distribution *** ANN is applied to a classifier for different faults ontheDC *** backpropagationneuralnetwork is used to predict the line current,and the fault detection threshold is obtained on the basis of the difference between the predicted current and the actual *** proposed method only uses local signals,with no requirement of a strict communication *** experiments are conducted for the proposed algorithm on a two-terminal DC distribution network modeled in the PSCAD/EMTDC and developed on the MATLAB *** results confirm that the proposed method can accurately detect and classify line faults within a few milliseconds and is not affected by fault locations,fault resistance,noise,and communication delay.

关键词： Artificial neural network DC distribution network fault detection

Pollination and seed dispersal of Aquilaria sinensis(Lour.)Gilg(Thymelaeaceae):An economic plant species with extremely small populations in China

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Plant Diversity 2016年第5期38卷 227-232页

作者： Gao Chen Changqiu Liu Weibang sun Kunrning Botanical Garden Kunrning Institute of BotanyChinese Academy of SciencesKunrning 650201YunnanChina Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina

Pollination and seed dispersal in angiosperms have long been investigated in order to understand the coevolution of plants and ***,the signals from flowers and/or seeds to attract pollinators and/or seed dispersers have received comparatively little *** this study,the pollination biology and seed dispersal of the vulnerable agarwood plant Aquilaria sinensis(Lour.) Gilg,a traditional medicinal plant in China,was studied in its natural distribution *** reproductive tactics of *** were studied in detail by employing various tests dealing with fruit set and also seed *** headspace extraction followed by GC-MS analysis was also performed in order to reveal the composition of floral *** results showed that noctuids and pyralids are the most effective pollinators of pollinator-dependent *** main compounds of the floral scent were(E,E)-α-Farnesene(61.9 ± 3.2%),trans-Ocimene(16.6 ± 1.2%),and Benzyl salicylate(4.6 ± 1.1%).The results obtained from seed dispersal experiments indicate that hornets are effective seed dispersers and they may play an important role in long-distance seed dispersal of *** on our findings,we recommend several protection methods for this threatened agarwood plant in China.

关键词： Aquilaria GC-MS Pollination Pyralidae Seed dispersal Vespa

An Analysis of the Steric Sea Level Change by Introducing Sea Surface Temperature

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Journal of Ocean University of China 2013年第1期12卷 37-44页

作者： sun Ruili LI Lei LI Peiliang Physical Oceanography Laboratory Ocean University of China

In this paper, we use the optimum interpolation sea surface temperature (OISST) provided by the National Center for Environmental Prediction (NCEP) to replace the temperature in the top three layers in the ISHII data, and make use of the modified ISHII temperature data to calculate the thermosteric sea level (called modified steric sea level (SSL) hereafter). We subtract the modified SSL and the steric sea level (called ordinary SSL hereafter) derived from the ISHII temperature and salinity from the steric sea level (SSL) provided by the Gravity Recovery and Climate Experiment (GRACE), respectively, and find that the rms error of the difference of the former is obviously smaller than that of the latter. Therefore we reach the conclusion that under the assumption that the GRACE SSL is accurate, the modified SSL can reflect the true steric sea level more accurately. Making use of the modified SSL, we can find that the modified SSL in sea areas of different spatial scales shows an obvious rising trend in the upper 0-700 m layer for the period 1982-2006. The global mean SSL rises with a rate of 0.6 mm year-1 .The modified SSLs in sea areas of different spatial scales all show obvious oscillations with period of one year. There are oscillations with periods of 4-8 years in global oceans and with periods of 2-7 years in the Pacific. The Empirical Orthogonal Function method is applied to the sea areas of different spatial scales and we find that the first modes all have obvious 1-year period oscillations, the first mode of the global ocean has 4-8 year period oscillations, and that of the Pacific has 2-6 year period oscillations. The spatial distribution of the linear rising trend of the global modified SSL in the upper 0-700 m layer is inhomogeneous with intense regional characteristics. The modified SSL linear trend indicates a zonal dipole in the tropical Pacific, rising in the west and descending in the east. In the North Atlantic, the modified SSL indicates a meridion

关键词： GRACE ISHII OISST steric sea level