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局部无缝垂直参考基准面的建立方法研究

武汉大学学报（信息科学版） 2006年第5期31卷 448-450页

作者：赵建虎张红梅 John e hughes Clarke 武汉大学测绘学院武汉市珞喻路129号430079 武汉大学动力与机械学院武汉市东湖南路8号430072 新伯伦瑞克大学图形组

为在局域建立一个无缝垂直参考基准面,提出了两步转换的思想和方法,即从大地高到正高然后到海图高。利用该方法,构造了Saint John河高程转换模型,并在该河段建立了无缝垂直参考基准面,且得到了实际验证。

关键词：大地高正常高海图基准海图基准高程

The response of temperature and hydrostatic pressure of zinc-blende Ga_xIn_(1-x)As semiconducting alloys

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Chinese Physics B 2012年第12期21卷 327-334页

作者： A.r.Degheidy e.B.elkenany Department of Physics Faculty of ScienceMansoura University

The electronic band structure of GaxIn1-xAs alloy is calculated by using the local empirical pseudo-potential method including the effective disorder potential in the virtual crystal approximation. The compositional effect of the electronic energy band structure of this alloy is studied with composition x ranging from 0 to 1. Various physical quantities such as band gaps, bowing parameters, refractive indices, and high frequency dielectric constants of the considered alloys with different Ga concentrations are calculated. The effects of both temperature and hydrostatic pressure on the calculated quantities are studied. The obtained results are found to be in good agreement with the available experimental and published data.

关键词： temperature hydrostatic pressure to GaxIn1-xAs alloys

Artificial senses for characterization of food quality

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Journal of Bionic engineering 2004年第3期1卷 159-173页

作者： r.e. Lacey Biological and Agricultural engineering Department Texas A & M University USA

Food quality is of primary concern in the food industry and to the consumer. Systems that mimic human senses have been developed and applied to the characterization of food quality. The five primary senses are: vision, hearing, smell, taste and touch. In the characterization of food quality, people assess the samples sensorially and differentiate “good”from “bad”on a continuum. However, the human sensory system is subjective, with mental and physical inconsistencies, and needs time to work. Artificial senses such as machine vision, the electronic ear, electronic nose, electronic tongue, artificial mouth and even artificial the head have been developed that mimic the human senses. These artificial senses are coordinated individually or collectively by a pat- tern recognition technique, typically artificial neural networks, which have been developed based on studies of the mechanism of the human brain. Such a structure has been used to formulate methods for rapid characterization of food quality. This research presents and discusses individual artificial sensing systems. With the concept of multi-sensor data fusion these sensor systems can work collectively in some way. Two such fused systems, artificial mouth and artificial head, are described and discussed. It indicates that each of the individual systems has their own artificially sensing ability to differentiate food samples. It further indicates that with a more complete mimic of human intelligence the fused systems are more powerful than the individual sys- tems in differentiation of food samples.

关键词： food quality artificial senses quality quantification artificial neural networks feature extraction multi-sensor data fusion

Grid Voltage Sensor-less Protection Scheme for One Cycle-Controlled Single-phase Photovoltaic Inverter Systems

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CSee Journal of Power and energy Systems 2022年第6期8卷 1720-1729页

作者： Venkata r.reddy Sreeraj e.S. are with National Institute of Technology Goa Farmagudi Ponda 403401India

One-cycle-controlled(OCC)inverters are suitable for small single-phase photovoltaic distributed-generator systems because of their simplicity,phase-locked-loop free structure,grid voltage sensor-less operation,and *** voltage sensor-less control helps reduce cost and increases reliability in *** various sensors are used for implementation of a protection *** this paper,a grid voltage sensorless protection scheme for OCC based single-phase inverter systems is *** estimated value of voltage at point of common coupling(VPCC)is used for protecting the system during over/under voltage conditions of the grid,implementing of voltage ride through conditions,and for disconnecting the grid during islanded *** VPCC is estimated from the measured inverter current,switching pulses,and the measured dc-link voltage using a second-order *** and experimental studies are performed to verify the efficacy of the proposed voltage sensor-less protection mechanism triggered using estimated VPCC.

关键词： One cycle control photovoltaic systems voltage sensorless voltage protection over/under voltage protection islanding detection

Ion-acoustic waves at the night side of Titan's ionosphere:higher-order approximation

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Communications in Theoretical Physics 2020年第5期72卷 70-77页

作者： S M Ahmed e r Hassib U M Abdelsalam r e Tolba W M Moslem Department of Mathematics Faculty of ScienceSuez UniversitySuezEgypt Department of Mathematics Faculty of ScienceFayoum UniversityFayoumEgypt Department of Mathematics Rustaq College of EducationOman Centre for Theoretical Physics The British University in Egypt(BUE)El-Shorouk CityCairoEgypt Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt

Nonlinear solitary waves are investigated for a plasma system at the night side of Titan's *** plasma model consists of three positive ions,namely C2H5^+,HCNH^+,and C3H5^+,as well as Maxwellian *** basic set of fluid equations is reduced to a Korteweg de-Vries(KdV)equation and linear inhomogeneous higher order KdV(LIHO-KdV)*** solitary wave solutions of both equations are obtained using a renormalization *** solitary waves'existence region and the wave profile are investigated,and their dependences on the plasma parameters at the night side of Titan's ionosphere are *** solitary waves'phase velocities are subsonic or supersonic,and the propagating pulses are usually *** effect of higher-order corrections on the perturbation theory is *** is found that the higher-order contribution makes the amplitude slightly taller,which is suitable for describing the solitary waves when the amplitude augments.

关键词： plasmas ion-acoustic waves planets and satellites:atmospheres

Assessing probabilities of unique events： Calibrating qualitative likelihood judgments into a probability distribution

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Chinese Business review 2010年第9期9卷 54-60页

作者： Warren r. hughes Department of economics University of Waikato Hamilton 3240 New Zealand

Multifaceted events in an organizational environment usually need to be assigned probabilities as a prerequisite to analytical decision-making. If the decision situation is unique, a lack of relevant historical frequency data may preclude use of traditional probability models such as the normal, binomial etc. In this case, an individual decision maker （DM） or an informed group of persons can input into a procedure as outlined here to determine a probability distribution that leads to the expected values of alternative actions or fair values of securities. The individual or group member must decide qualitatively on the extent to which one event is ＂more likely＂ than another where both events are ranked adjacent （i.e., closest to each other） in terms of likelihood. even though the individual or group members may lack experience in orthodox probability assessment, these pairwise ＂more likely＂ judgments on the relative likelihood of events are not overly demanding for persons familiar with the possible outcomes in the situation under analysis.

关键词： decision analysis probability assessment Bayesian revision strategic planning

Isogeometric Collocation:A Mixed Displacement-Pressure Method for Nearly Incompressible elasticity Dedicated to Professor Karl Stark Pister for his 95th birthday

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Computer Modeling in engineering & Sciences 2021年第12期129卷 1125-1150页

作者： S.Morganti F.Fahrendorf L.De Lorenzis J.A.evans T.J.r.hughes A.reali Department of electrical Computer and Biomedical EngineeringUniversita degli Studi di PaviaPavia27100Italy Institute of Applied Mechanics Technische Universitat BraunschweigBraunschweig38106Germany Department of Mechanical and Process engineering Zurich8092Switzerland Department of Aerospace engineering Sciences University of Colorado BoulderColorado80309USA Institute for Computational engineering and Sciences The University of Texas at AustinTexas78712USA Department of Civil engineering and Architecture Universita degli Studi di PaviaPavia27100Italy

We investigate primal and mixed u−p isogeometric collocation methods for application to nearly-incompressible isotropic *** primal method employs Navier’s equations in terms of the displacement unknowns,and the mixed method employs both displacement and pressure *** benchmarks for what might be considered acceptable accuracy,we employ constant-pressure Abaqus finite elements that are widely used in engineering *** a basis of comparisons,we present results for compressible *** the methods were completely satisfactory for the compressible ***,results for low-degree primal methods exhibited displacement locking and in general deteriorated in the nearly-incompressible *** results for the mixed methods behaved very well for two of the problems we studied,achieving levels of accuracy very similar to those for the compressible *** third problem,which we consider a“torture test”presented a more complex story for the mixed methods in the nearly-incompressible case.

关键词： Isogeometric analysis isogeometric collocation nearly-incompressible elasticity

Mid/far-infrared photo-detectors based on graphene asymmetric quantum wells

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Chinese Physics B 2016年第9期25卷 573-580页

作者： e Ben Salem r Chaabani S Jaziri Institut Preparatoire aux etudes d'Ingenieurs de Tunis 2 Rue Jawaher Lel Nahrou Monfleury 1089 Tunisie Laboratoire de Physique de la Matiere Condensee Departement de Physique Faculte des Sciences de Tunis Campus Universitaire 2092 Tunisie Departement de Physique Faculte des Sciences de Bizerte Jarzouna 7021 Bizerte

We conducted a theoretical study on the electronic properties of a single-layer graphene asymmetric quantum *** of energy levels is limited by electron–hole conversion at the barrier interfaces and free-electron ***–hole conversion at the barrier interfaces can be controlled by introducing an asymmetry between barriers and taking into account the effect of the interactions of the graphene sheet with the *** interaction with the substrate induces an effective mass to carriers,allowing observation of Fabry–P′erot resonances under normal incidence and extinction of Klein *** asymmetry,between barriers creates a transmission gap between confined states and free-electron continuum,allowing the large graphene asymmetric quantum well to be exploited as a photo-detector operating at mid-and far-infrared frequency regimes.

关键词： graphene quantum wells reflection coefficient photo-detector

Structure,stability,catalytic activity,and polarizabilities of small iridium clusters

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Chinese Physics B 2018年第6期27卷 225-230页

作者： Francisco e Jorge José r da Costa Venaancio Unidade Academica dc Ffsica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Departamento de Ffsica Universidade Federal do Espfrito Santo 29060-900 Vitoria Brazil

At the second order Douglas–Kroll–Hess（DKH2） level, the B3 PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters（Irn, n≤8）. These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n≤4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior,whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified.

关键词： B3PW91 functional all-electron basis sets DKH2 calculations iridium clusters polarizabilities