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APPROXIMATION BY WALSH-KACZMARZ-FEJR MEANS ON THE HARDY SPACE

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Acta Mathematica Scientia 2014年第5期34卷 1593-1602页

作者： george TEPHNADZE Department of Mathematics Faculty of Exact and Natural Sciences Tbilisi State UniversityChavchavadze Str. 1 Tbilisi 0128 Georgia Department of Engineering Sciences and Mathematics Lule University of TechnologySE-971 87 Lule Sweden

The main aim of this paper is to find necessary and sufficient conditions for the convergence of Walsh-Kaczmarz-Fej′er means in the terms of the modulus of continuity on the Hardy spaces Hp, when 0〈p≤1/2.

关键词： Walsh-Kaczmarz system Fej6r means martingale Hardy space modulus ofcontinuity

Estimating spatial attribute means in a GIS environment

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Science China Earth Sciences 2010年第2期53卷 181-188页

作者： CHRISTAKOS george Department of Geography San Diego State UniversitySan Diego CA 92182-4493USA

The estimation of geographical attributes is a crucial matter for many real-world problems,and the issue of accuracy stands out when the estimation is used for between-regions *** this work,our concern is area attribute estimation in a GIS *** estimate the area attribute value with a mean Kriging technique,and the probability distribution of the estimate is *** is the best linear unbiased observed spatial population mean estimate and can be used in more relaxed situations than the block Kriging *** theoretical analysis and empirical study show that the mean Kriging technique outperforms the ordinary Kriging,spatial random sampling,and simple random sampling techniques in estimating the observable spatial population mean across space.

关键词： spatial mean mean Kriging spatial dependence GIS

Simulation of heterogeneous two-phase media using random fields and level sets

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Frontiers of Structural and Civil Engineering 2015年第2期9卷 114-120页

作者： george STEFANOU Institute of Structural Analysis & Antiseismic Research School of Civil Engineering National Technical University of AthensZografou Campus Athens 15780 Greece Institute of Structural Analysis & Dynamics of Structures Department of Civil Engineering Aristotle University of ThessalonikiThessaloniki 54124 Greece

The accurate and efficient simulation of random heterogeneous media is important in the framework of modeling and design of complex materials across multiple length scales. It is usually assumed that the morphology of a random microstructure can be described as a non-Gaussian random field that is completely defined by its multivariate distribution. A particular kind of non-Gaussian random fields with great practical importance is that of translation fields resulting from a simple memory-less transformation of an underlying Gaussian field with known second-order statistics. This paper provides a critical examination of existing random field models of heterogeneous two-phase media with emphasis on level-cut random fields which are a special case of translation fields. The case of random level sets, often used to represent the geometry of physical systems, is also examined. Two numerical examples are provided to illustrate the basic features of the different approaches.

关键词： two-phase media microstructure random fields level sets shape recovery

Linear and non-linear pseudocapacitances with or without diffusion control

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Progress in Natural Science:Materials International 2021年第6期31卷 792-800页

作者： george Zheng Chen Department of Chemical and Environmental Engineering and Advanced Materials Research Group Faculty of Engineering University of Nottingham

Pseudocapacitance is an important reversible charge storage mechanism in many electrode materials. Although the concept was first proposed in early 1960s, it has been more widely studied following the observation of rectangular cyclic voltammograms(CVs) when testing some transition metal oxides and electronically conducting polymers, and the association with supercapacitor. However, interpretation of pseudocapacitance is inconsistent in the literature. Although all agree that materials are pseudocapacitive if they undergo Faradaic reactions and exhibit rectangular CVs, some have regarded any surface confined Faradaic reactions which may present non-rectangular or even peak-shaped CVs to be pseudocapacitive. In the case of rectangular CVs, the amount of charge stored in the electrode is a linear function of the electrode potential, whilst for non-rectangular or peakshaped CVs, the relationship is non-linear. It is shown in this article that only linear pseudocapacitance is of relevance to supercapacitor, but non-linear pseudocapacitance may find applications in rechargeable battery and supercapattery. Further, it is clarified that the equation i = kv + kvis useful in analysis of electrode kinetics in terms of surface confinement and diffusion control. However, this kinetic equation is blind to the thermodynamically determined charge storage mechanisms as shown by experimental evidence, and should not be used to differentiate non-capacitive Faradaic processes from pseudocapacitance, either linear or non-linear.

关键词： Pseudocapacitance Cyclic voltammetry Galvanostatic charging and discharging Supercapacitor Rechargeable battery Supercapattery

Nafamostat mesylate attenuates the pathophysiologic sequelae of neurovascular ischemia

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Neural Regeneration Research 2020年第12期15卷 2217-2234页

作者： george Zaki Ghali Michael george Zaki Ghali United States Environmental Protection Agency ArlingtonVAUSA Department of Toxicology Purdue UniversityWest LafayetteINUSA Department of Neurological Surgery University of California San FranciscoSan FranciscoCAUSA Department of Neurobiology and Anatomy Drexel University College of MedicinePhiladelphiaPAUSA

Nafamostat mesylate,an apparent soi-disant panacea of sorts,is widely used to anticoagulate patients undergoing hemodialysis or cardiopulmonary bypass,mitigate the inflammatory response in patients diagnosed with acute pancreatitis,and reverse the coagulopathy of patients experiencing the commonly preterminal disseminated intravascular coagulation in the Far *** serine protease inhibitor nafamostat mesylate exhibits significant neuroprotective effects in the setting of neurovascular *** mesylate generates neuroprotective effects by attenuating the enzymatic activity of serine proteases,neuroinflammatory signaling cascades,and the endoplasmic reticulum stress responses,downregulating excitotoxic transient receptor membrane channel subfamily 7 cationic currents,modulating the activity of intracellular signal transduction pathways,and supporting neuronal survival brain-derived neurotrophic factor/TrkB/ERK1/2/CREB,nuclear factor kappa *** effects collectively reduce neuronal necrosis and apoptosis and prevent ischemia mediated disruption of blood-brain barrier *** clinical applications of these compounds may mitigate ischemic reperfusion injury in patients undergoing cardiac,hepatic,renal,or intestinal transplant,preventing allograft rejection,and treating solid organ *** effects mediated by nafamostat mesylate support the wise conduct of randomized prospective controlled trials in Western countries to evaluate the clinical utility of this compound.

关键词： apoptosis cerebrovascular excitotoxicity infarction ischemia nafamostat mesylate necrosis neuroprotection serine protesae subarachnoid hemorrhage

Navigation sensors and systems in GNSS degraded and denied environments

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Chinese Journal of Aeronautics 2015年第1期28卷 1-10页

作者： george T.Schmidt IEEE Aerospace and Electronic Systems Society

Position, velocity, and timing（PVT） signals from the Global Positioning System（GPS）are used throughout the world but the availability and reliability of these signals in all environments has become a subject of concern for both civilian and military applications. This presentation summarizes recent advances in navigation sensor technology, including GPS, inertial, and other navigation aids that address these concerns. Also addressed are developments in sensor integration technology with several examples described, including the Bluefin-21 system mechanization.

关键词： navigation inertial GNSS environments receiver degraded military addressed presentation advances

An Algorithm for Constructing 3D Struts

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Journal of Computer Science & Technology 2009年第1期24卷 56-64页

作者： george W.Hart Department of Computer Science Stony Brook UniversityStony BrookNY 11794U.S.A.

A simple robust ＂strut algorithm＂ is presented which, when given a graph embedded in 3D space, thickens its edges into solid struts. Various applications, crystallographic and sculptural, are shown in which smooth high-genus forms are the output. A toolbox of algorithmic techniques allow for a variety of novel, visually engaging forms that express a mathematical aesthetic. In sculptural examples, hyperbolic tessellations in the Poincare plane are transformed in several ways to three-dimensional networks of edges embodied within a plausibly organic organization. By the use of different transformations and adjustable parameters in the algorithms, a variety of attractive forms result. The techniques produce watertight boundary representations that can be built with solid freeform fabrication equipment. The final physical output satisfies the ＂coolness criterion,＂ that passers by will pick them up and say ＂Wow, that＇s cool!＂

关键词： sculpture solid modeling echinoderm algorithms fine arts computer-aided design

A TWO-LEVEL GENETIC ALGORITHM FOR SCHEDULING IN ASSEMBLY ISLANDS WITH FIXED-POSITION LAYOUTS

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Journal of Systems Science and Systems Engineering 2010年第2期19卷 150-161页

作者： george Q.HUANG Department of Industrial and Manufacturing Systems Engineering The University of Hong Kong

This paper focuses on the scheduling problem in assembly islands environment with fixed-position layouts. In such configuration, the product normally remains in one location for its entire manufacturing period while machines, materials and workers are moved to an assembly site called an assembly island. This production layout has some unique features such as moving assembly workers, tools and materials; limited space at assembly site; considerable distance between islands. The authors first give the definition and mathematical model for the scheduling problem and then propose a two-level genetic algorithm to obtain a near optimal solution to minimize the makespan. Experimental results show that this algorithm is effective. The performance analysis of the proposed algorithm indicates that it is more efficient in the airline or shipbuilding industry than in the machine or tool final assembly companies.

关键词： Assembly islands scheduling genetic algorithm

Traveling wave effect on the seismic response of a steel arch bridge subjected to near fault ground motions

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Earthquake Engineering and Engineering Vibration 2007年第3期6卷 245-257页

作者：徐艳 george C Lee MCEER University at BuffaloNY 14260 USA Department of Bridge EngineeringTongji UniversityShanghai 200092China MCEER University at BuffaloNY 14260USA

In the 1990s, several major earthquakes occurred throughout the world, with a common observation that near fault ground motion （NFGM） characteristics had a distinct impact on causing damage to civil engineering structures that could not be predicted by using far field ground motions. Since then, seismic responses of structures under NFGMs have been extensively examined, with most of the studies focusing on structures with relatively short fundamental periods, where the traveling wave effect does not need to be considered. However, for long span bridges, especially arch bridges, the traveling wave （only time delay considered） effect may be very distinct and is therefore important. In this paper, the results from a case study on the seismic response of a steel arch bridge under selected NFGMs is presented by considering the traveling wave effect with variable apparent velocities. The effects of fling step and long period pulses of NFGMs on the seismic responses of the arch bridge are also discussed.

关键词： traveling wave effect arch bridge near fault ground motion fling step long period pulses