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COmPACTLY SUPPORTED BOX-SPLINE WAVELETS

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Analysis in theory and Applications 1992年第3期8卷 77-100页

作者： C.K.Chui J.Stckler J.D.Ward center for approximation theory department of mathematics texas a&m university college station TX 77843-3368 department of mathematics university of Duisburg D-4100 Duisburg Germany

A general procedure for constructing multivariate non-tensor-product wavelets that gen- erate an orthogonal decomposition of L^2(R~),s≥ 1,is described and applied to yield explicit formulas for compactly supported spline-wavelets based on the multiresolution analysis of L^2(R^s),1≤s≤3,generated by any box spline whose direction set constitutes a unimodular *** particular,when univariate cardinal B-splines are considered,the minimally sup- ported cardinal spline-wavelets of Chui and Wang are recovered.A refined computational scheme for the orthogonalization of spaces with compactly supported wavelets is given.A recursive approximation scheme for“truncated”decomposition sequences is developed and a sharp error bound is included.A condition on the symmetry or anti-symmetry of the wavelets is applied to yield symmetric box-spline wavelets.

关键词： COmPACTLY SUPPORTED BOX-SPLINE WAVELETS

approximation of the Spectral Fractional Powers of the Laplace-Beltrami Operator

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Numerical mathematics(theory,methods and Applications) 2022年第4期15卷 1193-1218页

作者： Andrea Bonito Wenyu Lei department of mathematics Texas A&M UniversityCollege StationTX 77843USA SISSA-International School for Advanced Studies Via Bonomea 26534136 TriesteItaly

We consider numerical approximation of spectral fractional Laplace-Beltrami problems on closed *** proposed numerical algorithms rely on their Balakrishnan integral representation and consists a sinc quadrature coupled with standard finite element methods for parametric *** up to a log term,optimal rate of convergence are observed and derived analytically when the discrepancies between the exact solution and its numerical approximations are measured in L^(2)and H^(1).The performances of the algorithms are illustrated on different settings including the approximation of Gaussian fields on surfaces.

关键词： Fractional diffusion Laplace-Beltrami FEm parametric methods on surfaces Gaussian fields

On the Radiative Properties of Ice Clouds:Light Scattering, Remote Sensing,and Radiation Parameterization

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Advances in Atmospheric Sciences 2015年第1期32卷 32-63页

作者： Ping YANG Kuo-Nan LIOU Lei BI Chao LIU Bingqi YI Bryan A.BAUm department of Atmospheric Sciences Texas A&M University College Station Joint Institute for Regional Earth System Science and Engineering and Department of Atmospheric and Oceanic SciencesUniversity of California Space Science and Engineering center University of Wisconsin-Madison

Presented is a review of the radiative properties of ice clouds from three perspectives： light scattering simulations, remote sensing applications, and broadband radiation parameterizations appropriate for numerical models. On the subject of light scattering simulations, several classical computational approaches are reviewed, including the conventional geometric-optics method and its improved forms, the finite-difference time domain technique, the pseudo-spectral time domain technique, the discrete dipole approximation method, and the T-matrix method, with specific applications to the computation of the singlescattering properties of individual ice crystals. The strengths and weaknesses associated with each approach are *** reference to remote sensing, operational retrieval algorithms are reviewed for retrieving cloud optical depth and effective particle size based on solar or thermal infrared（IR） bands. To illustrate the performance of the current solar- and IR-based retrievals, two case studies are presented based on spaceborne observations. The need for a more realistic ice cloud optical model to obtain spectrally consistent retrievals is demonstrated. Furthermore, to complement ice cloud property studies based on passive radiometric measurements, the advantage of incorporating lidar and/or polarimetric measurements is *** performance of ice cloud models based on the use of different ice habits to represent ice particles is illustrated by comparing model results with satellite observations. A summary is provided of a number of parameterization schemes for ice cloud radiative properties that were developed for application to broadband radiative transfer submodels within general circulation models（GCms）. The availability of the single-scattering properties of complex ice habits has led to more accurate radiation parameterizations. In conclusion, the importance of using nonspherical ice particle models in GCm simulations for climate studies is

关键词： ice clouds light scattering remote sensing radiative property parameterization

Non-Darcian Flow Toward a Finite-Diameter Vertical Well in a Confined Aquifer

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Pedosphere 2008年第3期18卷 288-303页

作者： WEN Zhang HUANG Guan-Hua ZHAN Hong-Bin college o.f Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 （China） Chinese-Israeli International center for Research and Training in Agriculture Beijing 100083 （China） department of Geology and Geophysics Texas A＆M University College Station Texas 77843-3115 （USA）

Non-Darcian radial flow toward a finite-diameter, fully penetrating well in a confined aquifer was analyzed on the basis of the Izbash equation with consideration of the wellbore storage effect. We derived semi-analytical solutions of drawdown by using the Boltzmann transform, and obtained approximate analytical solutions of the drawdown at early and late times. mATLAB programs were developed to facilitate computation of the semi-analytical solutions. The turbulence factor v which was directly related to the pumping rate appeared to have negligible influence upon the wellbore well function at early times, but imposed significant influence at intermediate and late times. However, the turbulence factor v imposed non-negligible influence upon the aquifer well function during the entire pumping period, provided that the observation point was not sufficiently close to the wellbore. Sensitivity analysis indicated that the power index n in the Izbash equation had less influence on the type curves at the face of the pumping wellbore, but had much greater influence upon the well function in the aquifer. As the n values increased, the drawdown in the aquifer decreased at early times and increased at late times. The Boltzmann transformation could only be used in an approximate sense for radial non-Darcian flow problems. This approximation would provide accurate solutions at early times, and introduce small but consistent discrepancies at intermediate and late times for the wellbore well function.

关键词： finite-diameter well non-Darcian flow' type curves well function wellbore storage

Prediction and assessment of demand response potential with coupon incentives in highly renewable power systems

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Protection and Control of modern Power Systems 2020年第1期5卷 124-137页

作者： Hao ming Bainan Xia Ki-Yeob Lee Adekunle Adepoju Srinivas Shakkottai Le Xie Electric Reliability Council of texas 800 Airport RdTaylorTX 78664USA Intellectual Ventures BellevueWAUSA department of Electrical and Computer Engineering Texas A&M UniversityCollege StationTXUSA

Demand Response(DR)provides both operational and financial benefits to a variety of stakeholders in the power *** example,in the deregulated market operated by the Electric Reliability Council of texas(ERCOT),load serving entities(LSEs)usually purchase electricity from the wholesale market(either in day-ahead or real-time market)and sign fixed retail price contracts with their ***,incentivizing end-consumers’load shift from peak to off-peak hours could benefit the LSE in terms of reducing its purchase of electricity under high prices from the real-time *** the first-of-its-kind implementation of Coupon Incentive-based Demand Response(CIDR),the EnergyCoupon project provides end-consumers with dynamic time-of-use DR event announcements,individualized load reduction targets with EnergyCoupons as the incentive for meeting these targets,as well as periodic lotteries using these coupons as lottery tickets for winning dollar-value gifts.A number of methodologies are developed for this special type of DR program including price/baseline prediction,individualized target setting and a lottery *** paper summarizes the methodologies,design,critical findings,as well as the potential generalization of such an *** of the EnergyCoupon with a conventional Time-of-Use(TOU)price-based DR program is also *** results in the year 2017 show that by combining dynamic coupon offers with periodic lotteries,the effective cost for demand response providers in EnergyCoupon can be substantially reduced,while achieving a similar level of demand reduction as conventional DR programs.

关键词： EnergyCoupon Incentive-based demand response Critical peak pricing Electricity market Prospect theory

BEST approximation FROm STEPPED SUBSPACES

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Analysis in theory and Applications 1985年第2期 29-49页

作者： Francis J.Narcowich Joseph D.Ward David A.Legg Indiana department of mathematics texas A & m university college station texas 77843 Fort Wayne Indiana university-Purdue university

1 .introduction Beeause nest algebras and,more generally,reflexive algebraswith a eo!nnl utative lattiee of Projeetions form a large,rieh elassof non一selfadjoint algebras,mueh interest has been shown in them

关键词： BEST approximation FROm STEPPED SUBSPACES

Rate Constitutive Theories of Orders n and 1n for Internal Polar Non-Classical Thermofluids without memory

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Applied mathematics 2016年第16期7卷 2033-2077页

作者： Karan S. Surana Stephen W. Long J. N. Reddy department of mechanical Engineering University of Kansas Lawrence USA department of mechanical Engineering Texas A & M University College Station USA

In recent papers, Surana et al. presented internal polar non-classical Continuum theory in which velocity gradient tensor in its entirety was incorporated in the conservation and balance laws. Thus, this theory incorporated symmetric part of the velocity gradient tensor (as done in classical theories) as well as skew symmetric part representing varying internal rotation rates between material points which when resisted by deforming continua result in dissipation (and/or storage) of mechanical work. This physics referred as internal polar physics is neglected in classical continuum theories but can be quite significant for some materials. In another recent paper Surana et al. presented ordered rate constitutive theories for internal polar non-classical fluent continua without memory derived using deviatoric Cauchy stress tensor and conjugate strain rate tensors of up to orders n and Cauchy moment tensor and its conjugate symmetric part of the first convected derivative of the rotation gradient tensor. In this constitutive theory higher order convected derivatives of the symmetric part of the rotation gradient tensor are assumed not to contribute to dissipation. Secondly, the skew symmetric part of the velocity gradient tensor is used as rotation rates to determine rate of rotation gradient tensor. This is an approximation to true convected time derivatives of the rotation gradient tensor. The resulting constitutive theory: (1) is incomplete as it neglects the second and higher order convected time derivatives of the symmetric part of the rotation gradient tensor;(2) first convected derivative of the symmetric part of the rotation gradient tensor as used by Surana et al. is only approximate;(3) has inconsistent treatment of dissipation due to Cauchy moment tensor when compared with the dissipation mechanism due to deviatoric part of symmetric Cauchy stress tensor in which convected time derivatives of up to order n are considered in the theory. The purpose of this pap

关键词： Rate Constitutive Theories Non-Classical Thermofluids Without memory Convected Time Derivatives Internal Rotation Gradient Tensor Generators and Invariants Cauchy moment Tensor

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铁-卟啉氧化还原酶体系催化机理的新解

化学教育 2016年第12期37卷 4-7页

作者：王志鹏袁金颖清华大学化学系北京100084 Chemistry department Texas A&M UniversityCollege Station TX 77840 USA)

铁-卟啉体系是生物体内众多重要氧化还原酶的活性中心。卟啉作为大环共轭配体,与中心铁原子的配位情况较小分子配合物复杂。其氧化还原反应的机理研究表明该过程中存在许多带正电荷或自由基的铁氧复合物中间体,这些中间体的空间结构和... 详细信息

铁-卟啉体系是生物体内众多重要氧化还原酶的活性中心。卟啉作为大环共轭配体,与中心铁原子的配位情况较小分子配合物复杂。其氧化还原反应的机理研究表明该过程中存在许多带正电荷或自由基的铁氧复合物中间体,这些中间体的空间结构和其中心铁原子的氧化态变化情况难以用经典的价键理论或价层电子对互斥理论等进行解释,且核心中间体的形成机理因不同酶而异。基于对其结构与氧化还原机理的分析,对几个相关问题提出一些较为简便的理解。以期对生物无机化学、配位化学、生物有机化学与酶学的教学和科研有所帮助。

关键词：铁-卟啉氧化还原酶化合物-I

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形式电荷之辨析与应用

化学教育（中英文） 2020年第22期41卷 98-104页

作者：王志鹏马新雨蒋振雄缑允梓张军颜惠娟许兵王鹏 department of Chemistry Texas A&M UniversityTX.United Surtes 7840 清华大学化学系北京100084 Division of Genetics Department of MedicineBrigham and Women's HospitalDepartment of Biological Chemistry and Molecular PharmacologyHarvard Medical SchoolBostonMA 0215 department of Biology Texas A&M UniversityCollege StationTX 77843 department of Plant Pathology and microbiology Texas A&M UniversityTXUnited States77843 北京师范大学教师教育研究中心北京100875 中山大学附属第一医院烧伤外科广东广州510080

从基础的元素化学和化学结构理论入手,系统性地举例辨析形式电荷的若干相关问题,讨论其与真实电荷、化合价、氧化态和电子对之别,并举例在前沿金属配合物等领域的应用。以期对化学基础教学与推广有助。

关键词：化学专业形式电荷化合价本科教育