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Reinforcement Learning and Its Applications in Modern Power and Energy Systems: A Review

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Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1029-1042页

作者： Di Cao Weihao Hu Junbo Zhao Guozhou Zhang Bin Zhang Zhou Liu Zhe Chen Frede Blaabjerg the Wide-area Measurement and Control Sichuan Provincial Key Laboratory School of Mechanical and Electrical EngineeringUniversity of Electronic Science and Technology of ChinaChengduChina the Department of Electrical and Computer Engineering Mississippi State UniversityStarkvilleMississippiUSA the Department of Energy Technology Aalborg UniversityAalborgDenmark

With the growing integration of distributed energy resources(DERs),flexible loads,and other emerging technologies,there are increasing complexities and uncertainties for modern power and energy *** brings great challenges to the operation and ***,with the deployment of advanced sensor and smart meters,a large number of data are generated,which brings opportunities for novel data-driven methods to deal with complicated operation and control *** them,reinforcement learning(RL)is one of the most widely promoted methods for control and optimization *** paper provides a comprehensive literature review of RL in terms of basic ideas,various types of algorithms,and their applications in power and energy *** challenges and further works are also discussed.

关键词： Reinforcement learning deep reinforcement learning power system operation and control optimization

Comparison of Cellular Automaton and Phase Field Models to Simulate Dendrite Growth in Hexagonal Crystals

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Journal of Materials Science & Technology 2012年第2期28卷 137-146页

作者： Mohsen Asle Zaeem Hebi Yin Sergio D. Felicelli Center for Advanced Vehicular Systems Mississippi State University Starkville MS 39759 USA Mechanical Engineering Department Mississippi State University Starkville MS 39759 USA Materials Processing Group Oak Ridge National Laboratory Oak Ridge TN 37831 USA

A cellular automaton （CA）-finite element （FE） model and a phase field （PF）-FE model were used to simulate equiaxed dendritic growth during the solidification of hexagonal metals. In the CA-FE model, the conservation equations of mass and energy were solved in order to calculate the temperature field, solute concentration, and the dendritic growth morphology. CA-FE simulation results showed reasonable agreement with the previously reported experimental data on secondary dendrite arm spacing （SDAS） vs cooling rate. In the PF model, a PF variable was used to distinguish solid and liquid phases similar to the conventional PF models for solidification of pure materials. Another PF variable was considered to determine the evolution of solute concentration. Validation of both models was performed by comparing the simulation results with the analytical model developed by Lipton-Glicksman-Kurz （LGK）, showing quantitatively good agreement in the tip growth velocity at a given melt undercooling. Application to magnesium alloy AZ91 （approximated with the binary Mg-8.9 wt% AI） illustrates the difficulty of modeling dendrite growth in hexagonal systems using CA-FE regarding mesh-induced anisotropy and a better performance of PF-FE in modeling multiple arbitrarily-oriented dendrites growth.

关键词： Dendrite growth Cellular automaton Phase-field model Finite element~ Magnesium alloy

Using probiotics to improve swine gut health and nutrient utilization

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Animal Nutrition 2017年第4期3卷 331-343页

作者： Shengfa F.Liao Martin Nyachoti Department of Animal and Dairy Sciences Mississippi State University Department of Animal Science University of Manitoba

To maintain a healthy gut is definitely key for a pig to digest and absorb dietary nutrients efficiently. A balanced microbiota(i.e., a healthy micro-ecosystem) is an indispensable constituent of a healthy ***, the live microorganisms which, when administered in adequate amounts, confer good health benefits onto the host, are a category of feed additives that can be used to replenish the gut microbial population while recuperating the host immune system. Besides their antitoxin and diarrhea reduction effects, dietary supplementation of probiotics can improve gut health, nutrient digestibilities and,therefore, benefit nutrient utilization and growth performance of pigs. Current knowledge in the literature pertinent to the beneficial effects of utilizing various probiotics for swine production has been comprehensively reviewed, and the safety and the risk issues related to probiotic usage have also been discussed in this paper. Considering that the foremost cost in a swine operation is feed cost, feed efficiency holds a very special, if not the paramount, significance in commercial swine production. Globally,the swine industry along with other animal industries is moving towards restricting and eventually a total ban on the usage of antibiotic growth promoters. Therefore, selection of an ideal alternative to the in-feed antibiotics to compensate for the lost benefits due to the ban on the antibiotic usage is urgently needed to support the industry for profitable and sustainable swine production. As is understood, a decision on this selection is not easy to make. Thus, this review paper aims to provide some much needed up-to-date knowledge and comprehensive references for swine nutritionists and producers to refer to before making prudent decisions and for scientists and researchers to develop better commercial products.

关键词： Probiotic Feed additive Gut health Antibiotic growth promoter Nutrition Swine

Avian succession along ecological gradients： Insight from species-poor and species-rich communities of Sylvia warblers

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Current Zoology 2011年第3期57卷 307-317页

作者： Alban GUILLAUMET Roger PRODON EPHE CEFE-CNRS UMR 5175 1919 route de Mende 34293 Montpellier cedex 5 France Department of Wildlife Fisheries & Aquaculture Mail Stop 9690 Mississippi State University Mississippi MS 39762 USA

The mechanisms responsible for species replacement during ecological successions is a long-standing and open debate. In this study, we examined the distribution of the Sardinian warbler Sylvia melanocephala along two grassland-to-forest gradients, one in a high-diversity area （Albera-Aspres chain in Catalonia： eight Sylvia warbler species） and one in a low-diversity area （Mount Hymittos in Greece： four species）. In Catalonia, distribution models suggested that the apparent exclusion of S. melanocephala from the open and forest ends of the gradient may be explained entirely by the preference of S. melanocephala for mid-successional shrublands. However, a joint analysis of both data sets revealed that： 1） S. melanocephala was more evenly dis- tributed along the vegetation gradient in Greece, suggesting ecological release in the low-diversity area; and 2） a distribution model assuming interspecific competition （based on the distribution of Sylvia species showing a negative co-occurrence pattern with S. melanocephala） had a significantly higher predictive ability than a distribution model based on habitat variables alone. Our study supports the view that species turnover along ecological gradients generally results from a combination of intrinsic preferences and interspecific competition [Current Zoology 57 （3）： 307-317, 2011].

关键词： Avian succession Cross-validation Diffuse competition Ecological release GLM Habitat selection Nichewidening Species distribution model

Asymptomatic early acute appendicitis initiated and diagnosed during colonoscopy: A case report

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World Journal of Gastroenterology 2005年第34期11卷 5398-5400页

作者： Michelle Petro Anil Minocha Division of Digestive Diseases university of mississippi Medical Center Jackson MS 39216 USA

Colonoscopic diagnosis of asymptomatic early acute appendicitis is exceedingly rare. Although obstruction of common physiologic mechanism of acute appendicitis, all of the previously documented cases in the literature have only shown a patent appendiceal lumen with pus flowing into the cecum. We present the case of a patient undergoing colonoscopy for colorectal cancer evaluation with no abdominal symptoms. An obstructed, swollen appendix was seen. The process was probably initiated during the colonoscopy, documenting perhaps the earliest stage of acute appendicitis for the first time. Endoscopic, CT and microsCOpic documentation of the case is also presented.

关键词： Colonoscopy Appendicitis Complications Endoscopy

Comparison and predicted equation of energy expenditure during walking or running among Caucasians,African Americans and Asians

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Sports Medicine and Health Science 2021年第3期3卷 171-176页

作者： Xi Jin Teresa Carithers Mark Loftin Nutrition and Hospitality Management The University of MississippiMSUSA Health Exercise Science and Recreation ManagementThe University of MississippiMSUSA

Knowledge of measured energy expenditure(EE)during walking and running is important for exercise ***,research on the EE comparison and EE predicted equation during walking or running among different ethnicities is *** purpose of the current study was to compare EE to walk or run 1 mile in Caucasian,African American and Asian adults and to develop a regression equation to predict EE to walk or run 1 *** hundred and twenty-four participants were included(71 Caucasians,68 African Americans and 85 Asians)with 3 groups(normal weight walking,overweight walking and running).EE was measured via indirect *** of variance was used to compare EE across *** regression analysis was employed for EE prediction,and the prediction equation was cross-validated.A significant EE difference was found between walking and running among three *** prediction equation was:EE=0.978 Body Weight-4.571 Gender(male=1;female=2)+3.524 Ethnicities(Caucasians=1,African Americans=2,Asians=3)+32.447(standard error of estimate=12.5 kcal·mile^(-1)).The equation was valid through cross-validation,so it is recommended to apply for calculating EE during walking or running 1 mile among Cauca-sians,African Americans and Asians.

关键词： Energy expenditure Predicted equation Caucasians African Americans Asians

A Spectral Time-Domain Method for Computational Electrodynamics

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Advances in Applied Mathematics and Mechanics 2009年第6期1卷 781-798页

作者： James V.Lambers Department of Mathematics University of Southern MississippiHattiesburgMS 39406-0001 USA

Ever since its introduction by Kane Yee over forty years ago,the finitedifference time-domain(FDTD)method has been a widely-used technique for solving the time-dependent Maxwell’s equations that has also inspired many other *** paper presents an alternative approach to these equations in the case of spatially-varying electric permittivity and/or magnetic permeability,based on Krylov subspace spectral(KSS)*** methods have previously been applied to the variable-coefficient heat equation and wave equation,and have demonstrated high-order accuracy,as well as stability characteristic of implicit timestepping schemes,even though KSS methods are *** methods for scalar equations compute each Fourier coefficient of the solution using techniques developed by Golub and Meurant for approximating elements of functions of matrices by Gaussian quadrature in the spectral,rather than physical,*** show how they can be generalized to coupled systems of equations,such as Maxwell’s equations,by choosing appropriate basis functions that,while induced by this coupling,still allow efficient and robust computation of the Fourier coefficients of each spatial component of the electric and magnetic *** also discuss the application of block KSS methods to problems involving non-self-adjoint spatial differential operators,which requires a generalization of the block Lanczos algorithm of Golub and Underwood to unsymmetric matrices.

关键词： Spectral methods Gaussian quadrature block Lanczos method Maxwell’s equations

Extracting Information from the Atom-Laser Wave Function Using Interferometric Measurement with a Laser Standing-Wave Grating

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Chinese Physics Letters 2001年第8期18卷 1000-1003页

作者： LIU Zheng-Dong ZENG Liang LIN Yu WU Qiang ZHU Shi-Yao Department of Physics Zhejiang UniversityHangzhou 310027 The university of Texas-Pan American EdinburgTX 78539U.S.A Department of Physics and Astronomy Mississippi State UniversityMississippi StateMS 39762U.S.A Department of Physics Hong Kong Baptist UniversityHong Kong

The reconstruction of the atom-laser wave function is performed using interferometric measurement with a standing-wave grating,and the results in this scheme are *** relation between the measurement data and the atomic wave function are also *** scheme is quite applicable and effectively avoids the initial random phase problem of the method that employs the laser running *** information which is encoded in the atom-laser wave is extracted.

关键词： wave scheme Wave

NUMERICAL MODELING OF SUSPENDED SEDIMENT TRANSPORT IN CHANNEL BENDS

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Journal of Hydrodynamics 2006年第4期18卷 411-417页

作者： HUANG Sui-liang JIAY．F,WANG Sam S. Y. College of Environmental Science and Engineering Nankai University Tianjin 300071 China National Center for Computational Hydroscience and Engineering The University of Mississippi Oxford USA

An algorithm to compute three-dimensional sediment transport effect was proposed in this paper to enhance the capability of depth-averaged numerical models. This algorithm took into account of non-uniform distributions of flow velocities and suspended sediment concentrations along water depth, it significantly enhanced the applicability of 2D models in simulating open channel flows, especially in channel bends. Preliminary numerical experiments in a U-shaped and a sine-generated experimental channel indicate that the proposed method performs quite well in predicting the change of bed-deformation in channel bends due to suspended sediment transport. This method provides an effective alternative for the simulations of channel morphodynamic changes.

关键词： algorithm dispersion terms bends suspended sediment transport 2D numerical model