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Algebraic test of relative form closure grasps with its implementation

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Science China(Technological Sciences) 2014年第7期57卷 1401-1410页

作者： xiong YouLun xiong tao WANG YuHui State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology

This paper presents an approach to algebraic detection of relative form closure for a multi-fingered grasp G and gives an attention to the classification of relative form *** or not a grasp G is of relative form closure has been verified by the geometric criterion 0?rintC[G](xiong Y L,xiong X *** structure and geometric interpretation of rigid complex fixture *** Trans Autom Sci Eng,2007,4:252–264;xiong Y *** of point contact restraint and qualitative analysis of robot *** China Ser A-Math,1994,37:629–640).Our aim is at transferring the geometric criterion into an algebraic formulation by a theorem that a grasp G is relative form closure,if,and only if the origin 0 can be represented as a positive convex combination of *** we develop a constructive procedure called ri-simplex algorithm to find a positive convex combination of G when it has relative form *** closure is considered as a special case of relative form closure,when the grasp G can affinely span the whole space,while partly relative form closure is referred to as form closed relative to a subset G1 of G.

关键词： relative form closure algebraic test PCC(positive convex combination) ri-simplex algorithm simplex grasp complex grasp

Conservative Discontinuous Galerkin/Hermite Spectral Method for the Vlasov-Poisson System

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Communications on Applied Mathematics and Computation 2022年第1期4卷 34-59页

作者： Francis Filbet tao xiong Institut de Mathématiques de Toulouse UniversitéPaul SabatierToulouse 31062France School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computing Xiamen UniversityXiamen 361005Fujian ProvinceChina

We propose a class of conservative discontinuous Galerkin methods for the Vlasov-Pois-son system written as a hyperbolic system using Hermite polynomials in the velocity *** schemes are designed to be systematically as accurate as one wants with prov-able conservation of mass and possibly total *** properties in general are hard to achieve within other numerical method frameworks for simulating the Vlasov-Poisson *** proposed scheme employs the discontinuous Galerkin discretization for both the Vlasov and the Poisson equations,resulting in a consistent description of the distribu-tion function and the electric *** simulations are performed to verify the order of the accuracy and conservation properties.

关键词： Energy conserving Discontinuous Galerkin method Hermite spectral method Vlasov-Poisson

A High Order Bound Preserving Finite Difference Linear Scheme for Incompressible Flows

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Communications in Computational Physics 2022年第6期32卷 126-155页

作者： Guoliang Zhang tao xiong School of Mathematical Sciences Xiamen UniversityXiamenFujian 361005P.R.China School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computing Xiamen UniversityXiamenFujian 361005P.R.China

We propose a high order finite difference linear scheme combined with ahigh order bound preserving maximum-principle-preserving (MPP) flux limiter tosolve the incompressible flow system. For such problem with highly oscillatory structure but not strong shocks, our approach seems to be less dissipative and much lesscostly than a WENO type scheme, and has high resolution due to a Hermite reconstruction. Spurious numerical oscillations can be controlled by the weak MPP fluxlimiter. Numerical tests are performed for the Vlasov-Poisson system, the 2D guidingcenter model and the incompressible Euler system. The comparison between the linearand WENO type schemes, with and without the MPP flux limiter, will demonstrate thegood performance of our proposed approach.

关键词： Finite difference scheme high order Hermite reconstruction MPP flux limiter incompressible flow Vlasov-Poisson

Influence of Probiotic Fermented Fruit and Vegetables on Human Health and the Related Industrial Development Trend

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Engineering 2021年第2期7卷 212-218页

作者： Qianqian Guan tao xiong Mingyong Xie State Key Laboratory of Food Science and Technology Nanchang 330047China College of Food Science and Technology Nanchang UniversityNanchang 330031China

The paper briefly discusses the relationship between chronic diseases and gut health,and points out that an imbalance of intestinal microflora and an inadequate intake of dietary fiber are two important causes of chronic *** paper also summarizes the research status of probiotic fermented fruit and vegetables,and discusses the main achievements of our group in this field and future developments of the related *** application of fermentation technology to fruit and vegetable processing and the development of a series of probiotic fermented fruit and vegetable products not only increase the added value of fruit and vegetables,but also organically combine probiotics and their active metabolites with prebiotics(dietary fiber,etc.),thereby promoting intestinal health as well as preventing and relieving chronic *** technology provides a new approach to the study of the effect of probiotics on human health,and will have a revolutionary influence on probiotic application and on the fruit and vegetable processing ***,fruit and vegetable fermentation technology has excellent market potential.

关键词： Probiotic Fermented fruit and vegetables Human health Chronic disease prevention

Profit Guided or Statistical Error Guided? A Study of Stock Index Forecasting Using Support Vector Regression

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Journal of Systems Science & Complexity 2017年第6期30卷 1425-1442页

作者： HU Zhongyi BAO Yukun CHIONG Raymond xiong tao School of Information Management Wuhan University School of Management Huazhong University of Science and Technology School of Electrical Engineering and Computing The University of Newcastle College of Economics and Management Huazhong Agricultural University

Stock index forecasting has been one of the most widely investigated topics in the field of financial forecasting. Related studies typically advocate for tuning the parameters of forecasting models by minimizing learning errors measured using statistical metrics such as the mean squared error or mean absolute percentage error. The authors argue that statistical metrics used to guide parameter tuning of forecasting models may not be meaningful, given the fact that the ultimate goal of forecasting is to facilitate investment decisions with expected profits in the future. The authors therefore introduce the Sharpe ratio into the process of model building and take it as the profit metric to guide parameter tuning rather than using the commonly adopted statistical metrics. The authors consider three widely used trading strategies, which include a na¨?ve strategy, a filter strategy and a dual moving average strategy, as investment scenarios. To verify the effectiveness of the proposed profit guided approach, the authors carry out simulation experiments using three global mainstream stock market indices. The results show that profit guided forecasting models are competitive, and in many cases produce significantly better performances than statistical error guided models. This implies thatprofit guided stock index forecasting is a worthwhile alternative over traditional stock index forecasting practices.

关键词： Financial market investment trading strategy parameter optimization stock index forecasting support vector regression

High Order Conservative Finite Difference/Fourier Spectral Methods for Inviscid Surface Quasi-Geostrophic Flows

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Communications in Computational Physics 2022年第10期32卷 1474-1509页

作者： Nan Zhang Zhiping Mao tao xiong School of Mathematical Sciences Xiamen UniversityXiamenFujian361005P.R.China School of Mathematical Sciences Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific ComputingXiamen UniversityXiamenFujian361005P.R.China

In this paper,we develop an effective conservative high order finite difference scheme with a Fourier spectral method for solving the inviscid surface quasigeostrophic equations,which include a spectral fractional Laplacian determining the vorticity for the transport velocity of the potential *** fractional Laplacian is approximated by a Fourier-Galerkin spectral method,while the time evolution of the potential temperature is discretized by a high order conservative finite difference *** essentially non-oscillatory(WENO)reconstructions are also considered for *** to a low regularity of problems involving such a fractional Laplacian,especially in the critical or supercritical regime,directly applying the Fourier spectral method leads to a very oscillatory transport velocity associated with the gradient of the vorticity,*** smooth *** of using an artificial filter,we propose to reconstruct the velocity from the vorticity with central difference *** results are performed to demonstrate the good performance of our proposed approach.

关键词： Finite difference WENO Fourier spectral fractional Laplacian surface quasigeostrophic flow

A New Property of Conjugated Polymer PFP: Catalytic Degradation of Methylene Blue Aqueous Solution

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Chinese Chemical Letters 2005年第10期16卷 1361-1363页

作者： Bi tao SU Shi xiong SHE Shi xiong MIN Zhan Ying MA Key Lab of Gansu Polymer Materials Department of Chemistry Northwest Normal University Lanzhou 730070

A new property of conjugated polymer poly（furancarbinol-co-phenol）（PFP） was studied. The target copolymer was used as a catalyst after proper heating treatment. And dye methylene blue （MB） could be fully degraded and largely mineralized on PFP, under natural light or even in dark, in a few minutes. Furthermore, the catalytic activity could be preserved after several runs and the catalyst was readily separated. The effect of calcination temperature was also observed.

关键词： PFP catalytic property MB degradation mineralization.

Theoretical Studies on Dehydrogenation Reactions in Mg2（BH4）2（NH2）2 Compounds

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Chinese Journal of Chemical Physics 2012年第6期25卷 676-680,I0003页

作者： Zheng Chen Zhe-ning Chen An-an Wu Guo-tao Wu Zhi-tao xiong Ping Chen Xin Xu State Key Laboratory for Physical Chemistry of Solid Surface Fujian Provincial Key Laboratoryof Theoretical and Computational Chemist04 College of Chemistry and Chemical Engineering XiamenUniversity Xiamen 361005 China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China MOE Laboratory for Computational Physical Science Shanghai Key Laboratory of Molecular Catalysisand Innovative Materials Department of Chemistry Center of Chemistry for Energy Materials FudanUniversity Shanghai 200433 China

Borohydrides have been recently hightlighted as prospective new materials due to their high gravimetric capacities for hydrogen storage. It is, therefore, important to under- stand the underlying dehydrogenation mechanisms for further development of these ma- terials. We present a systematic theoretical investigation on the dehydrogenation mecha- nisms of the Mg2（BH4）2（NH2）2 compounds. We found that dehydrogenation takes place most likely via the intermolecular process, which is favorable both kinetically and thermo- dynamically in comparison with that of the intramolecular process. The dehydrogenation of Mg2（BH4）2（NH2）2 initially takes place via the direct combination of the hydridie H in BH4 and the protie H in NH2-, followed by the formation of Mg-H and subsequent ionic recombination of Mg-Hδ-…Hδ＋-N.

关键词： Hydrogen storage Density functional theory Metal borohydride

Hypothalamic-pituitary-derived melanocortin axis links to myelopoiesis and immunotherapy

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The Innovation 2023年第4期4卷 9-10页

作者： Chao Zhang Ya-xiong tao Fundamental Research Center Shanghai Yangzhi Rehabilitation Hospital(Shanghai Sunshine Rehabilitation Center)Tongji UniversityShanghai 201619China Department of Anatomy Physiology and PharmacologyCollege of Veterinary MedicineAuburn UniversityAuburnAL 36849USA

Melanocortins,including a-melanocyte stimulating hormone(a-MSH),b-MSH,g-MSH,and adrenocorticotropin(ACTH),are ancient peptides highly conserved in vertebrates and exhibit diverse well-established functions,including dermal pigmentation,adrenal steroidogenesis and cell proliferation,energy homeostasis,and inflammation.1 Melanocortins exert their diverse functions through five melanocortin receptors(MCRs),MC1R-MC5R,numbered based on the sequence of their cloning.

关键词： homeostasis cortin stimulating