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Large Deviations and Moderate Deviations for Kernel Density Estimators of Directional Data

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Acta Mathematica Sinica,English Series 2010年第5期26卷 937-950页

作者： fu qing GAO Li Na LI School of Mathematics and Statistics Wuhan University Wuhan 430072 P. R. China Department of Mathematics Tongji University Shanghai 200092 P. R. China

Let fn be the non-parametric kernel density estimator of directional data based on a kernel function K and a sequence of independent and identically distributed random variables taking values in d-dimensional unit sphere Sd-1. It is proved that if the kernel function is a function with bounded variation and the density function f of the random variables is continuous, then large deviation principle and moderate deviation principle for {sup x∈sd-1 ｜fn（x） - E（fn（x））｜, n ≥ 1} hold.

关键词： kernel density estimator directional data moderate deviations large deviations

Crisis of Transient Chaos

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Chinese Physics Letters 2002年第7期19卷 901-903页

作者： Wang wen-Xiu, Lu Yun-qing Department of Physics and Complexity Science Center Yangzhou University

A new kind of crisis, which is marked by a sudden change of a strange repeller, is observed in an electronic relaxation oscillator. Firstly, by its simplified piecewise linear model, we show analytically that a strange repeller appears after a hole-induced crisis, and that the fractal dimension of the strange repeller and the average lifetime of the iterations in the region occupied by the original attractor suddenly change at the critical parameter value when the repeller disappears. Our numerical investigation convinces us that the corresponding phenomenon can be found in the original electronic relaxation oscillator.

关键词： Fractal dimension

Analysis method and algorithm design of biological sequence problem based on generalized k-mer vector

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Applied Mathematics(A Journal of Chinese Universities) 2021年第1期36卷 114-127页

作者： LIU wen-li WU qing-biao Department of Mathematics Zhejiang UniversityHangzhou 310027China Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology Zhejiang UniversityZijingang CampusHangzhou 310012China

K-mer can be used for the description of biological sequences and k-mer distribution is a tool for solving sequences analysis problems in *** can use k-mer vector as a representation method of the k-mer distribution of the biological ***,such as similarity calculations or sequence assembly,can be described in the k-mer vector *** helps us to identify new features of an old sequence-based problem in bioinformatics and develop new algorithms using the concepts and methods from linear space *** this study,we defined the k-mer vector space for the generalized biological *** meaning of corresponding vector operations is explained in the biological *** presented the vector/matrix form of several widely seen sequence-based problems,including read quantification,sequence assembly,and pattern detection *** advantages and disadvantages are ***,we implement a tool for the sequence assembly problem based on the concepts of k-mer vector *** shows the practicability and convenience of this algorithm design strategy.

关键词： vector space biological sequence k-mer algorithm design analysis method.

Strange quark star and the parameter space of the quasi-particle model

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Communications in Theoretical Physics 2021年第10期73卷 125-131页

作者： wen-Hua Cai qing-Wu Wang College of physics Sichuan UniversityChengdu 610064China

The properties of strange quark stars are studied within the quasi-particle model. Taking into account chemical equilibrium and charge neutrality, the equation of state(EOS) of(2+ 1)-flavor quark matter is obtained. We illustrate the parameter spaces with constraints from two aspects: one is based on the astronomical results of PSR J0740+ 6620 and GW 170 817,and the other is based on the constraints proposed from the theoretical study of a compact star that the EOS must ensure the tidal deformability Λ_(1.4)=190_(-120)^(+390) and support a maximum mass above 1.97M⊙. It is found that neither type of constraints can restrict the parameter space of the quasi-particle model in a reliable region and thus we conclude that the low mass compact star cannot be a strange quark star.

关键词： strange quark compact star tidal deformability quasi-particle model neutron star

Altered intrinsic functional connectivity of the primary visual cortex in youth patients with comitant exotropia: a resting state fMRI study

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International Journal of Ophthalmology(English edition) 2018年第4期11卷 668-673页

作者： Pei-wen Zhu Xin Huang Lei Ye Nan Jiang Yu-Lin Zhong qing Yuan fu-qing Zhou Yi Shao Department of Ophthalmology the First Affiliated Hospital of Nanchang University Eye Center Renmin Hospital of Wuhan University Wuhan University Department of Radiology the First Affiliated Hospital of Nanchang University

AIM： To evaluate the differences in the functional connectivity（FC） of the primary visual cortex（V1） between the youth comitant exotropia（CE） patients and health subjects using resting functional magnetic resonance imaging（f MRI） ***： Totally, 32 CEs（25 males and 7 females） and 32 healthy control subjects（HCs）（25 males and 7 females） were enrolled in the study and underwent the MRI scanning. Two-sample t-test was used to examine differences in FC maps between the CE patients and HCs. RESULTS： The CE patients showed significantly less FC between the left brodmann area（BA17） and left lingual gyrus/cerebellum posterior lobe, right middle occipital gyrus, left precentral gyrus/postcentral gyrus and right inferior parietal lobule/postcentral gyrus. Meanwhile, CE patients showed significantly less FC between right BA17 and right middle occipital gyrus（BA19, 37）.CONCLUSION： Our findings show that CE involves abnormal FC in primary visual cortex in many regions, which may underlie the pathologic mechanism of impaired fusion and stereoscopic vision in CEs.

关键词： comitant exotropia functional connectivity primary visual cortex spontaneous activity

Chemical and biological flocculation process to treat municipal sewage and analysis of biological function

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Journal of Environmental Sciences 2005年第1期17卷 163-167页

作者： XIASi-qing YANGDian-hai XUBin ZHAOJian-fu StateKeyLaboratoryofPollutionControlandResourceReuse TongjiUniversityShanghai200092China

The pilot scale experimental apparatus and the procedure of the chemical and biological flocculation process to verify the feasibility in treating Shanghai municipal sewage were introduced in this paper. In addition, the biological function of the process was discussed. The results of optimal running showed that in the reaction tank, the concentration of mixed liquor suspended solid(MLSS) was 2 g/L, hydraulic retention time(HRT) was 35 min, dosage of liquid polyaluminium chloride(PAC) was 60 mg/L, and the concentration of polyacrylamide(PAM) was 0 5 mg/L. The effluent average concentrations of COD Cr , TP, SS and BOD 5 were 50 mg/L, 0 62 mg/L, 18 mg/L, and 17 mg/L, respectively. These were better than the designed demand. In addition, the existence of biological degradation in this system was proven by several methods. The removal efficiencies of the chemical and biological flocculation process were 20% higher than that of the chemical flocculation process above at the same coagulant dosage. The treatment process under different situations was evaluated on a pilot scale experiment, and the results provided magnificent parameters and optimal condition for future operation of the plant.

关键词： chemical and biological flocculation process municipal water biological function

Effect of C-Tetramethyl Calix[4]resorcinarene Acrylate on Curing Behavior and Film Properties of Thiol-acrylate Coating System

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Chemical Research in Chinese Universities 2009年第5期25卷 760-766页

作者： fu Qi SHI wen-fang Joint Laboratory of Polymer Thin Films and Solution Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 P. R. China

An octa-functional acrylate of C-tetramethyl calix[4]resorcinarene（CMC-4-RA） was facilely synthesized and characterized with ^1H NMR, ^13C NMR and FTIR spectroscopy. The CMC-4-RA was added to a thiol-acrylate system with different mass ratios, and exposed to a middle pressure mercury lamp. The maximum photopolymerization rate and final vinyl group conversion in the cured film increased greatly along with CMC-4-RA addition that was monitored with Photo-DSC. The tensile strength and pendulum hardness were improved significantly after the addition of CMC-4-RA. With increasing the content of CMC-4-RA to 60%（mass fraction）, the glass transition temperature increased from 34.2 ℃ to 84.1 ℃; the cross-link density was calculated to be increased from 23.83 mmol/cm^3 to 82.40 mmol/cm^3 according to dynamic mechanical thermal analysis; the thermostability was greatly improved.

关键词： Calixresorcinarene Acrylate UV curing Film

Approaching the theoretical capacity of TiO_(2) anode in a photorechargeable lithium-ion battery

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Nano Research 2024年第4期17卷 2655-2662页

作者： wen Yan Jie Wang qing Hu Jingjing fu Mohamed K.Albolkany Tian Zhang Xiao Lu Fei Ye Bo Liu School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China

New generation of lithium-ion batteries(LIBs)integrating solar energy conversion and storage is emerging,as they could solve the fluctuation problem in the utilization of solar ***-rechargeable lithium-ion batteries(PR-LIBs)are ideal devices for such target,in which solar energy is converted into electricity and stored in *** order to achieve the high performance of PR-LIB,it is crucial to develop dual-function electrode materials that can synergistically capture solar energy and store ***,we present photo-rechargeable lithium-ion batteries using defective black TiO_(2) as photoanode prepared by lithium *** photoanode exhibits excellent photo response in full solar spectrum with a capacity enhancement of 46.4%under illumination,corresponding to the energy conversion efficiency of 4.4%at the current density of 1 A·g^(-1).When illumination is applied at 20 mA·g^(-1),the battery capacity increases from~230 in dark to~349 mAh·g^(-1) at the first cycle,and then stabilizes at 310 mAh·g^(-1),approaching the theoretical value of 335 mAh·g^(-1) of TiO_(2) electrode *** finding provides thoughts for breaking the capacity limitations in TiO_(2) and paves the way for powering LIBs by solar illumination.

关键词： photo-rechargeable lithium-ion batteries photoanode defective TiO_(2)(D-TiO_(2))

Combined effect of repetitive transcranial magnetic stimulation and physical exercise on cortical plasticity

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Neural Regeneration Research 2020年第11期15卷 1986-1994页

作者： Ya-wen Yang wen-Xiu Pan qing Xie Department of Rehabilitation Medicine Ruijin HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Department of Rehabilitation Medicine Shanghai Ruijin Rehabilitation HospitalShanghaiChina

Physical exercise can minimize dysfunction and optimize functional motor recovery after stroke by modulating cortical ***,the limitation of physical exercise is that large amounts of time and effort are necessary to significantly improve motor function,and even then,substantial exercise may not be sufficient to normalize the observed ***,interventions that could be used to strengthen physical exercise-induced neuroplasticity may be valuable in treating hemiplegia after *** transcranial magnetic stimulation seems to be a viable strategy for enhancing such *** a non-invasive cortical stimulation technique,repetitive transcranial magnetic stimulation is able to induce longterm plastic changes in the motor ***,repetitive transcranial magnetic stimulation was found to optimize the plastic changes caused by motor training,thereby enhancing the long-term effects of physical exercise in stroke ***,it is believed that the combination of repetitive transcranial magnetic stimulation and physical exercise may represent a superior method for restoring motor function after stroke.

关键词： functional recovery motor cortex neuroplasticity physical exercise primary motor cortex repetitive transcranial magnetic stimulation stroke