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Complementarity of CFD,experimentation and reactor models for solving challenging fluidization problems

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Particuology 2010年第6期8卷 498-500页

作者： John R. grace Tingwen Li Department of Chemical and Biological Engineering University of British Columbia Vancouver V6T 1Z3 Canada National Energy Technology Laboratory 3610 Collins Ferry Rd Morgantown WV26507 USA

Experimentalists, numerical modellers and reactor modellers need to work together, not only just for validation of numerical codes, but also to shed fundamental light on each other＇s problems and underlying assumptions. Several examples are given, Experimental gas axial dispersion data provide a means of choosing the most appropriate boundary condition （no slip, partial slip or full slip） for particles at the wall of fluidized beds. CFD simulations help to identify how close ＂two-dimensional＂ experimental columns are to being truly two-dimensional and to representing three-dimensional columns. CFD also can be used to provide a more rational means of establishing assumptions needed in the modelling of two-phase fluidized bed reactors, for example how to deal with cases where there is a change in molar flow （and hence volumetric flow） as a result of chemical reactions.

关键词： Fluidization Mixing Computational Fluid dynamics Wall slip Reactor modelling Volume change

Analytical and Observational Investigation of Colors Effects on Drag Reduction in Penguins

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Journal of Bionic Engineering 2022年第4期19卷 1036-1053页

作者： grace Tenorio Anna Zagrai William Allen Mostafa Hassanalian Department of Mechanical Engineering New Mexico TechSocorroNM87801USA Cottonwood Valley Charter School SocorroNM87801USA Depertment of Biosciences Swansea UniversitySwanseaSA28PPUK

All 18 extant species of penguin are strongly countershaded,having dark dorsal and light ventral *** this paper,the thermal effects of this body color in penguins are investigated through analytical and observational ***,a thermal analysis that takes into account the environmental characteristics of penguins’habitats,fluxes,and morphology is used to analytically calculate penguin dorsal surface ***,a turbulent analytical solution for a heated boundary layer over a flat plate is applied to show that the dark color on the top of the penguins’bodies is very effective at skin drag *** verify this result,a 2D model penguin is computationally analyzed at different temperatures,confirming in principle underwater skin drag reduction through color-based surface warming with efficiency savings of up to 30%.Finally,to study how color-based increases in body surface temperatures are maintained through foraging dives,thermal cameras are used to measure the surface temperature of captive penguins before and after *** study shows conceptually that dark dorsal coloration in penguins could have a significant influence on in-water drag.

关键词： Animal coloration Drag Energy balance Irradiation Penguin Thermal imaging Skin friction

Intensity-curvature functional based digital high pass filter of the bivariate cubic B-spline model polynomial function

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Visual Computing for Industry,Biomedicine,and Art 2019年第1期2卷 75-92页

作者： Carlo Ciulla grace Agyapong Faculty of Information Systems VisualizationMultimediaand AnimationUniversity of Information Science and TechnologySt.Paul the ApostlePartizanska B.B.Ohrid 6000Republic of North Macedonia Faculty of Communication Networks and Security University of Information Science and TechnologySt.Paul the ApostlePartizanska B.B.Ohrid 6000Republic of North Macedonia

This research addresses the design of intensity-curvature functional(ICF)based digital high pass filter(HPF).ICF is calculated from bivariate cubic B-spline model polynomial function and is called ICF-based *** order to calculate ICF,the model function needs to be second order differentiable and to have non-null classic-curvature calculated at the origin(0,0)of the pixel coordinate *** theoretical basis of this research is called intensitycurvature *** concept envisions to replace signal intensity with the product between signal intensity and sum of second order partial derivatives of the model *** of the concept in two-dimensions(2D)makes it possible to calculate the ICF of an *** treatise is presented to demonstrate the hypothesis that ICF is HPF *** evidence then validates the assumption and also extends the comparison between ICF-based HPF and ten different HPFs among which is traditional HPF and particle swarm optimization(PSO)based *** comparison of image space and k-space magnitude,results indicate that HPFs behave *** HPF filtering and ICF-based filtering are superior to PSO-based *** filtered with traditional HPF are sharper than images filtered with ICF-based *** contribution of this research can be summarized as follows:(1)Math description of the constraints that ICF need to obey to in order to function as HPF;(2)Math of ICF-based HPF of bivariate cubic B-spline;(3)Image space comparisons between HPFs;(4)K-space magnitude comparisons between *** research provides confirmation on the math procedure to use in order to design 2D HPF from a model bivariate polynomial function.

关键词： Intensity-curvature functional High pass filter B-spline Particle swarm optimization K-space

Farnesoid X receptor,the bile acid sensing nuclear receptor,in liver regeneration

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Acta Pharmaceutica Sinica B 2015年第2期5卷 93-98页

作者： Guodong Li grace L.Guo Department of General Surgery the Fourth Hospital of Harbin Medical University Division of Biobank Research Department of General Surgery the Fourth Hospital of Harbin Medical University Department of Pharmacology and Toxicology Ernest Mario School of Pharmacy Rutgers the State University of New Jersey

The liver is unique in regenerative potential, which could recover the lost mass and function after injury from ischemia and resection. The underlying molecular mechanisms of liver regeneration have been extensively studied in the past using the partial hepatectomy(PH) model in rodents, where 2/3 PH is carried out by removing two lobes. The whole process of liver regeneration is complicated, orchestrated event involving a network of connected interactions, which still remain fully elusive. Bile acids(BAs) are ligands of farnesoid X receptor(FXR), a nuclear receptor of ligand-activated transcription factor. FXR has been shown to be highly involved in liver regeneration. BAs and FXR not only interact with each other but also regulate various downstream targets independently during liver regeneration. Moreover, recent findings suggest that tissue-specific FXR also contributes to liver regeneration significantly. These novel findings suggest that FXR has much broader role than regulating BA, cholesterol, lipid and glucose metabolism. Therefore, these researches highlight FXR as an important pharmaceutical target for potentialuse of FXR ligands to regulate liver regeneration in clinic. This review focuses on the roles of BAs and FXR in liver regeneration and the current underlying molecular mechanisms which contribute to liver regeneration.

关键词： Farnesoid X receptor Liver regeneration Bile acids Fibroblast growth factor 15 Liver-intestine croass talk Transmembrane G protein coupled receptor 5

Designing mechanically tough graphene oxide materials using deep reinforcement learning

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npj Computational Materials 2022年第1期8卷 2139-2147页

作者： Bowen Zheng Zeyu Zheng grace X.Gu Department of Mechanical Engineering University of CaliforniaBerkeleyCA94720USA Department of Industrial Engineering and Operations Research University of CaliforniaBerkeleyCA94720USA

Graphene oxide(GO)is playing an increasing role in many ***,it remains unanswered how to strategically distribute the functional groups to further enhance *** utilize deep reinforcement learning(RL)to design mechanically tough *** design task is formulated as a sequential decision process,and policy-gradient RL models are employed to maximize the toughness of *** show that our approach can stably generate functional group distributions with a toughness value over two standard deviations above the mean of random *** addition,our RL approach reaches optimized functional group distributions within only 5000 rollouts,while the simplest design task has 2×10^(11)***,we show that our approach is scalable in terms of the functional group density and the GO *** present research showcases the impact of functional group distribution on GO properties,and illustrates the effectiveness and data efficiency of the deep RL approach.

关键词： toughness tough oxide

Hydrodynamics and solids mixing in fluidized beds with inclined-hole distributors

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Particuology 2019年第2期17卷 19-28页

作者： Alhussain Bakhurji Xiaotao Bi John R. grace Fluidization Research Centre Department of Chemical and Biological Engineering University of British Columbia Vancouver V6TJZ3 Canada

Experimental fluidization results were compared for three gas distributors with the same opening ratio but different orifice in clinations (30,45 , and 90 ). Hydrodynamic studies were con ducted with glass beads (diameter 154p.m) to evaluate the impacts of orifice inclination and static bed depth on pressure drop, pressure drop fluctuations, bed expansion, and minimum fluidization velocity. Solids residence time distributions were determined using phosphoresce nt tracer particles (mea n diameter 76 pm), activated by ultraviolet light. The bed pressure drop was higher with the inclined-hole distributors and increased with static bed height. In a shallow bed, the inclined-hole distributors gave less expansion;however, in deep beds, the orifice angle had negligible influence on bed expansion. The minimum fluidization velocity varied with static bed height for the inclined-hole distributors and was higher for steeper angles. The turnover time estimated using bubbling-bed equations matched the experimental results well for vertical mixing. Probes and ports at the walls of the fluidization column reduced the dense-phase downward velocity by up to 40%. The tangential particle velocity was highest for the 30 -hole distributor and decreased with increasing orifice angle. Tangential mixing was described by a dispersion model;the dispersion coefficient for the inclined-hole distributors was approximately twice that for the 90 -hole distributor in a shallow bed.

关键词： Swirling fluidized bed Fluidization Solids mixing Inclined-hole distributor

Design of Neural Network Based Wind Speed Prediction Model Using GWO

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Computer Systems Science & Engineering 2022年第2期40卷 593-606页

作者： R.Kingsy grace R.Manimegalai Department of Computer Science and Engineering Sri Ramakrishna Engineering CollegeCoimbatore641022India Department of Computer Science and Engineering PSG Institute of Technology and Applied ResearchCoimbatore641062India

The prediction of wind speed is imperative nowadays due to the increased and effective generation of wind *** power is the clean,free and conservative renewable *** is necessary to predict the wind speed,to implement wind power *** paper proposes a new model,named WT-GWO-BPNN,by integrating Wavelet Transform(WT),Back Propagation Neural Network(BPNN)and GreyWolf Optimization(GWO).The wavelet transform is adopted to decompose the original time series data(wind speed)into approximation and detailed ***-BPNN is applied to predict the wind *** is used to optimize the parameters of back propagation neural network and to improve the convergence *** work uses wind power data of six months with 25,086 data points to test and verify the performance of the proposed *** proposed work,WT-GWO-BPNN,predicts the wind speed using a three-step procedure and provides better *** Absolute Error(MAE),Mean Squared Error(MSE),Mean absolute percentage error(MAPE)and Root mean squared error(RMSE)are calculated to validate the performance of the proposed *** results demonstrate that the proposed model has better performance when compared to other methods in the literature.

关键词： Wind speed wavelet transform back propagation neural network grey wolf optimization time series

Diabetic Retinopathy Diagnosis Using ResNet with Fuzzy Rough C-Means Clustering

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Computer Systems Science & Engineering 2022年第8期42卷 509-521页

作者： R.S.Rajkumar A.grace Selvarani Sri Ramakrishna Engineering College Coimbatore641022India

Diabetic Retinopathy(DR)is a vision disease due to the long-term prevalenceof Diabetes *** affects the retina of the eye and causes severedamage to the *** not treated on time it may lead to permanent vision lossin diabetic ***’s development in science has no medication to cureDiabetic ***,if diagnosed at an early stage it can be controlledand permanent vision loss can be *** to the diabetic population,experts to diagnose Diabetic Retinopathy are very less in particular to local *** an automatic computer-aided diagnosis for DR detection is *** paper,we propose an unsupervised clustering technique to automatically clusterthe DR into one of its five development *** deep learning based unsupervisedclustering is made to improve itself with the help of fuzzy rough c-meansclustering where cluster centers are updated by fuzzy rough c-means clusteringalgorithm during the forward pass and the deep learning model representationsare updated by Stochastic Gradient Descent during the backward pass of *** proposed method was implemented using python and the results were takenon DGX server with Tesla V100 GPU *** experimental result on the publicallyavailable Kaggle dataset shows an overall accuracy of 88.7%.The proposedmodel improves the accuracy of DR diagnosis compared to the existingunsupervised algorithms like k-means,FCM,auto-encoder,and FRCM withalexnet.

关键词： Diabetic retinopathy detection diabetic retinopathy diagnosis fuzzy rough c-means clustering unsupervised CNN clustering

In vivo mouse models to study bile acid synthesis and signaling

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国际肝胆胰疾病杂志:英文版 2023年第5期22卷 466-473页

作者： Anisha Bhattacharya Rulaiha E Taylor grace L Guo Department of Pharmacology and Toxicology Ernest Mario School of PharmacyRutgersThe State University of New JerseyPiscatawayNew JerseyUSA Rutgers Center for Lipid Research RutgersThe State University of New JerseyNew BrunswickNew JerseyUSA Environmental and Occupational Health Sciences Institute RutgersThe State University of New JerseyPiscatawayNew JerseyUSA VA New Jersey Health Care System Veterans Administration Medical CenterEast OrangeNew JerseyUSA

The synthesis of bile acids(BAs)is carried out by complex pathways characterized by sequential chemical reactions in the liver through various cytochromes P450(CYP)and other *** the integrity of these pathways is crucial for normal physiological function in mammals,encompassing hepatic and neurological *** on the deficiencies in BA synthesis genes offers valuable insights into the significance of BAs in modulating farnesoid X receptor(FXR)signaling and metabolic *** creating mouse knockout(KO)models,researchers can manipulate deficiencies in genes involved in BA synthesis,which can be used to study human diseases with BA *** KO mouse models allow for a more profound understanding of the functions and regulations of genes responsible for BA ***,KO mouse models shed light on the distinct characteristics of individual BA and their roles in nuclear receptor ***,alterations of BA synthesis genes in mouse models have distinct differences when compared to human diseases caused by the same BA synthesis gene *** review summarizes several mouse KO models used to study BA synthesis and related human diseases,including mice deficient in Cyp7a1,Cyp27a1,Cyp7a1/Cyp27a1,Cyp8b1,Cyp7b1,Cyp2c70,Cyp2a12,and Cyp2c70/Cyp2a12,as well as germ-free mice.

关键词： Bile acid Species difference Farnesoid X receptor Liver diseases