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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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Thermodynamic Fit Functions of the Two-Phase Fluid and Critical Exponents 被引量:1
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作者 Albrecht Elsner 《Engineering(科研)》 2014年第12期789-826,共38页
Two-phase fluid properties such as entropy, internal energy, and heat capacity are given by thermodynamically defined fit functions. Each fit function is expressed as a temperature function in terms of a power series ... Two-phase fluid properties such as entropy, internal energy, and heat capacity are given by thermodynamically defined fit functions. Each fit function is expressed as a temperature function in terms of a power series expansion about the critical point. The leading term with the critical exponent dominates the temperature variation between the critical and triple points. With β being introduced as the critical exponent for the difference between liquid and vapor densities, it is shown that the critical exponent of each fit function depends (if at all) on β. In particular, the critical exponent of the reciprocal heat capacity c﹣1 is α=1-2β and those of the entropy s and internal energy u are?2β, while that of the reciprocal isothermal compressibility?κ﹣1T is γ=1. It is thus found that in the case of the two-phase fluid the Rushbrooke equation conjectured α +?2β + γ=2 combines the scaling laws resulting from the two relations c=du/dT and?κT=dlnρ/dp. In the context with c, the second temperature derivatives of the chemical potential μ and vapor pressure p are investigated. As the critical point is approached, ﹣d2μ/dT2 diverges as c, while?d2p/dT2 converges to a finite limit. This is explicitly pointed out for the two-phase fluid, water (with β=0.3155). The positive and almost vanishing internal energy of the one-phase fluid at temperatures above and close to the critical point causes conditions for large long-wavelength density fluctuations, which are observed as critical opalescence. For negative values of the internal energy, i.e. the two-phase fluid below the critical point, there are only microscopic density fluctuations. Similar critical phenomena occur when cooling a dilute gas to its Bose-Einstein condensate. 展开更多
关键词 CRITICAL Condition U = 0 CRITICAL OPALESCENCE Rushbrooke Equation THERMODYNAMIC FIT functions for Saturated Water Vapor and Liquid Volumes Vapor Pressure Chemical Potential Entropy Internal ENERGY Free ENERGY Heat Capacity
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Monitoring Zenithal Total Delays over the three different climatic zones from IGS GPS final products:A comparison between the use of the VMF1 and GMF mapping functions 被引量:4
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作者 Benachour Labib Jianguo Yan +2 位作者 Jean-Pierre Barriot Fangzhao Zhang Peng Feng 《Geodesy and Geodynamics》 2019年第2期93-99,共7页
The International GNSS Service(IGS) final products(ephemeris and clocks-correction) have made the GNSS an indispensable low-cost tool for scientific research, for example sub-daily atmospheric water vapor monitoring. ... The International GNSS Service(IGS) final products(ephemeris and clocks-correction) have made the GNSS an indispensable low-cost tool for scientific research, for example sub-daily atmospheric water vapor monitoring. In this study, we investigate if there is a systematic difference coming from the choice between the Vienna Mapping Function 1(VMF1) and the Global Mapping Function(GMF) for the modeling of Zenith Total Delay(ZTD) estimates, as well as the Integrated Precipitable Water Vapor(IPWV) estimates that are deduced from them. As ZTD estimates cannot be fully separated from coordinate estimates, we also investigated the coordinate repeatability between subsequent measurements.For this purpose, we monitored twelve GNSS stations on a global scale, for each of the three climatic zones(polar, mid-latitudes and tropical), with four stations on each zone. We used an automated processing based on the Bernese GNSS Software Version 5.2 by applying the Precise Point Positioning(PPP)approach, L3 Ionosphere-free linear combination, 7 cutoff elevation angle and 2 h sampling. We noticed an excellent agreement with the ZTD estimates and coordinate repeatability for all the stations w.r.t to CODE(the Center for Orbit Determination in Europe) and USNO(US Naval Observatory) products, except for the Antarctic station(Davis) which shows systematic biases for the GMF related results. As a final step, we investigated the effect of using two mapping functions(VMF1 and GMF) to estimate the IPWV,w.r.t the IPWV estimates provided by the Integrated Global Radiosonde Archive(IGRA). The GPS-derived IPWV estimates are very close to the radiosonde-derived IPWV estimates, except for one station in the tropics(Tahiti). 展开更多
关键词 International GNSS Service (IGS) VIENNA MAPPING FUNCTION 1 (VMF1) Global MAPPING FUNCTION (GMF) Precise Point Positioning (PPP) Zenith TOTAL DELAY (ZTD) Zenith Wet DELAY (ZWD) Integrated Precipitable Water Vapor (IPWV)
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Hyperbolic Fibonacci and Lucas Functions, “Golden” Fibonacci Goniometry, Bodnar’s Geometry, and Hilbert’s Fourth Problem—Part II. A New Geometric Theory of Phyllotaxis (Bodnar’s Geometry) 被引量:2
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作者 Alexey Stakhov Samuil Aranson 《Applied Mathematics》 2011年第2期181-188,共8页
This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries–New ... This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries–New Geometric Theory of Phyllotaxis (Bodnar’s Geometry) and Hilbert’s Fourth Problem based on the Hyperbolic Fibonacci and Lucas Functions and “Golden” Fibonacci λ-Goniometry (λ > 0 is a given positive real number). Although these discoveries refer to different areas of science (mathematics and theoretical botany), however they are based on one and the same scientific ideas-the “golden mean,” which had been introduced by Euclid in his Elements, and its generalization—the “metallic means,” which have been studied recently by Argentinian mathematician Vera Spinadel. The article is a confirmation of interdisciplinary character of the “Mathematics of Harmony”, which originates from Euclid’s Elements. 展开更多
关键词 Euclids Fifth Postulate Lobachevskis GEOMETRY HYPERBOLIC GEOMETRY PHYLLOTAXIS Bodnars GEOMETRY Hilberts Fourth Problem The Golden and Metallic Means Binet Formukas HYPERBOLIC FIBONACCI and Lucas functions Gazale Formulas Golden FIBONACCI λ-Goniometry
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A comparison of piecewise cubic Hermite interpolating polynomials,cubic splines and piecewise linear functions for the approximation of projectile aerodynamics 被引量:5
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作者 C.A.Rabbath D.Corriveau 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期741-757,共17页
Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and repr... Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and representative numerical model of projectile flight requires a relatively good approximation of the aerodynamics.The aerodynamic coefficients of the projectile model should be described as a series of piecewise polynomial functions of the Mach number that ideally meet the following conditions:they are continuous,differentiable at least once,and have a relatively low degree.The paper provides the steps needed to generate such piecewise polynomial functions using readily available tools,and then compares Piecewise Cubic Hermite Interpolating Polynomial(PCHIP),cubic splines,and piecewise linear functions,and their variant,as potential curve fitting methods to approximate the aerodynamics of a generic small arms projectile.A key contribution of the paper is the application of PCHIP to the approximation of projectile aerodynamics,and its evaluation against a set of criteria.Finally,the paper provides a baseline assessment of the impact of the polynomial functions on flight trajectory predictions obtained with 6-degree-of-freedom simulations of a generic projectile. 展开更多
关键词 Aerodynamic coefficients PIECEWISE POLYNOMIAL functions CUBIC splines Curve fitting PIECEWISE linear functions PIECEWISE CUBIC HERMITE interpolating POLYNOMIAL PROJECTILE modelling and simulation Fire control inputs Precision Ballistic computer software
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Hyperbolic Fibonacci and Lucas Functions, “Golden” Fibonacci Goniometry, Bodnar’s Geometry, and Hilbert’s Fourth Problem—Part III. An Original Solution of Hilbert’s Fourth Problem 被引量:3
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作者 Alexey Stakhov Samuil Aranson 《Applied Mathematics》 2011年第3期283-293,共11页
This article refers to the “Mathematics of Harmony” by Alexey Stakhov [1], a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries—New Geom... This article refers to the “Mathematics of Harmony” by Alexey Stakhov [1], a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries—New Geometric Theory of Phyl-lotaxis (Bodnar’s Geometry) and Hilbert’s Fourth Problem based on the Hyperbolic Fibonacci and Lucas Functions and “Golden” Fibonacci -Goniometry ( is a given positive real number). Although these discoveries refer to different areas of science (mathematics and theoretical botany), however they are based on one and the same scien-tific ideas—The “golden mean,” which had been introduced by Euclid in his Elements, and its generalization—The “metallic means,” which have been studied recently by Argentinian mathematician Vera Spinadel. The article is a confirmation of interdisciplinary character of the “Mathematics of Harmony”, which originates from Euclid’s Elements. 展开更多
关键词 Euclids Fifth Postulate Lobachevskis GEOMETRY HYPERBOLIC GEOMETRY Phyllotaxis Bodnars GEOMETRY Hilberts FOURTH Problem the Golden and Metallic Means Binet Formulas HYPERBOLIC FIBONACCI and Lucas functions Gazale Formulas Golden FIBONACCI -Goniometry
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Hyperbolic Fibonacci and Lucas Functions, “Golden” Fibonacci Goniometry, Bodnar’s Geometry, and Hilbert’s——Part I. Hyperbolic Fibonacci and Lucas Functions and “Golden” Fibonacci Goniometry 被引量:1
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作者 Alexey Stakhov Samuil Aranson 《Applied Mathematics》 2011年第1期74-84,共11页
This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discove-ries—New... This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discove-ries—New Geometric Theory of Phyllotaxis (Bodnar’s Geometry) and Hilbert’s Fourth Problem based on the Hyperbolic Fibonacci and Lucas Functions and “Golden” Fibonacci λ-Goniometry ( λ > 0 is a given positive real number). Although these discoveries refer to different areas of science (mathematics and theoretical botany), however they are based on one and the same scientific ideas—the “golden mean”, which had been introduced by Euclid in his Elements, and its generalization—the “metallic means”, which have been studied recently by Argentinian mathematician Vera Spinadel. The article is a confirmation of interdisciplinary character of the “Mathematics of Harmony”, which originates from Euclid’s Elements. 展开更多
关键词 Euclids Fifth Postulate Lobachevskis GEOMETRY HYPERBOLIC GEOMETRY Phyllotaxis Bodnars GEOMETRY Hilberts Fourth Problem The Golden and Metallic Means Binet Formulas HYPERBOLIC FIBONACCI and Lucas functions Gazale Formulas Golden FIBONACCI λ-Goniometry
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Associated Hermite Polynomials Related to Parabolic Cylinder Functions
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2019年第1期15-42,共28页
In analogy to the role of Lommel polynomials ?in relation to Bessel functions Jv(z) the theory of Associated Hermite polynomials in the scaled form ?with parmeter v to Parabolic Cylinder functions Dv(z) is developed. ... In analogy to the role of Lommel polynomials ?in relation to Bessel functions Jv(z) the theory of Associated Hermite polynomials in the scaled form ?with parmeter v to Parabolic Cylinder functions Dv(z) is developed. The group-theoretical background with the 3-parameter group of motions M(2) in the plane for Bessel functions and of the Heisenberg-Weyl group W(2) for Parabolic Cylinder functions is discussed and compared with formulae, in particular, for the lowering and raising operators and the eigenvalue equations. Recurrence relations for the Associated Hermite polynomials and for their derivative and the differential equation for them are derived in detail. Explicit expressions for the Associated Hermite polynomials with involved Jacobi polynomials at argument zero are given and by means of them the Parabolic Cylinder functions are represented by two such basic functions. 展开更多
关键词 Bessel functions Lommel POLYNOMIALS PARABOLIC CYLINDER functions ASSOCIATED Hermite POLYNOMIALS Jacobi POLYNOMIALS Recurrence Relations Lowering and Raising Operators Heisenberg-Weyl GROUP Motion GROUP of Plane Irreducible Representations
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AN INTEGRATION METHOD WITH FITTING CUBIC SPLINE FUNCTIONS TO A NUMERICAL MODEL OF 2ND-ORDER SPACE-TIME DIFFERENTIAL REMAINDER——FOR AN IDEAL GLOBAL SIMULATION CASE WITH PRIMITIVE ATMOSPHERIC EQUATIONS
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作者 辜旭赞 张兵 王明欢 《Journal of Tropical Meteorology》 SCIE 2013年第4期388-396,共9页
In this paper,the forecasting equations of a 2nd-order space-time differential remainder are deduced from the Navier-Stokes primitive equations and Eulerian operator by Taylor-series expansion.Here we introduce a cubi... In this paper,the forecasting equations of a 2nd-order space-time differential remainder are deduced from the Navier-Stokes primitive equations and Eulerian operator by Taylor-series expansion.Here we introduce a cubic spline numerical model(Spline Model for short),which is with a quasi-Lagrangian time-split integration scheme of fitting cubic spline/bicubic surface to all physical variable fields in the atmospheric equations on spherical discrete latitude-longitude mesh.A new algorithm of"fitting cubic spline—time step integration—fitting cubic spline—……"is developed to determine their first-and2nd-order derivatives and their upstream points for time discrete integral to the governing equations in Spline Model.And the cubic spline function and its mathematical polarities are also discussed to understand the Spline Model’s mathematical foundation of numerical analysis.It is pointed out that the Spline Model has mathematical laws of"convergence"of the cubic spline functions contracting to the original functions as well as its 1st-order and 2nd-order derivatives.The"optimality"of the 2nd-order derivative of the cubic spline functions is optimal approximation to that of the original functions.In addition,a Hermite bicubic patch is equivalent to operate on a grid for a 2nd-order derivative variable field.Besides,the slopes and curvatures of a central difference are identified respectively,with a smoothing coefficient of 1/3,three-point smoothing of that of a cubic spline.Then the slopes and curvatures of a central difference are calculated from the smoothing coefficient 1/3 and three-point smoothing of that of a cubic spline,respectively.Furthermore,a global simulation case of adiabatic,non-frictional and"incompressible"model atmosphere is shown with the quasi-Lagrangian time integration by using a global Spline Model,whose initial condition comes from the NCEP reanalysis data,along with quasi-uniform latitude-longitude grids and the so-called"shallow atmosphere"Navier-Stokes primitive equations in the spherical coordinates.The Spline Model,which adopted the Navier-Stokes primitive equations and quasi-Lagrangian time-split integration scheme,provides an initial ideal case of global atmospheric circulation.In addition,considering the essentially non-linear atmospheric motions,the Spline Model could judge reasonably well simple points of any smoothed variable field according to its fitting spline curvatures that must conform to its physical interpretation. 展开更多
关键词 NUMERICAL forecast and NUMERICAL SIMULATION 2nd-order SPACE-TIME differential REMAINDER NUMERICAL model cubic spline functions Navier-Stokes PRIMITIVE EQUATIONS quasi-Lagrangian time-split integration scheme global SIMULATION case
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Special Numbers on Analytic Functions
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作者 Yilmaz Simsek 《Applied Mathematics》 2014年第7期1091-1098,共8页
The aim of this paper is to give some analytic functions which are related to the generating functions for the central factorial numbers. By using these functions and p-adic Volkenborn integral, we derive many new ide... The aim of this paper is to give some analytic functions which are related to the generating functions for the central factorial numbers. By using these functions and p-adic Volkenborn integral, we derive many new identities associated with the Bernoulli and Euler numbers, the central factorial numbers and the Stirling numbers. We also give some remarks and comments on these analytic functions, which are related to the generating functions for the special numbers. 展开更多
关键词 BERNOULLI NUMBERS Euler NUMBERS The Central FACTORIAL NUMBERS Array Polynomials STIRLING NUMBERS of the First KIND and the Second KIND Generating Function Functional Equation Analytic functions
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Uniformly Bounded Set-Valued Composition Operators in the Spaces of Functions of Bounded Variation in the Sense of Riesz
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作者 Wadie Aziz Nelson Merentes 《International Journal of Modern Nonlinear Theory and Application》 2015年第4期226-233,共8页
We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty ... We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty bounded closed and convex values, are an affine function. 展开更多
关键词 j-Variation in the SENSE of RIESZ SET-VALUED functions Left and Right Regularizations UNIFORMLY BOUNDED OPERATOR Composition (Nemytskij) OPERATOR Jensen Equation
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Consequences of Invariant Functions for the Riemann Hypothesis
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作者 Michael Mark Anthony 《Advances in Pure Mathematics》 2025年第1期36-72,共37页
This paper attempts to form a bridge between a sum of the divisors function and the gamma function, proposing a novel approach that could have significant implications for classical problems in number theory, specific... This paper attempts to form a bridge between a sum of the divisors function and the gamma function, proposing a novel approach that could have significant implications for classical problems in number theory, specifically the Robin inequality and the Riemann hypothesis. The exploration of using invariant properties of these functions to derive insights into twin primes and sequential primes is a potentially innovative concept that deserves careful consideration by the mathematical community. 展开更多
关键词 LambertW Function Principal Branch Riemann Hypothesis ITERATIONS Robin Inequality Robin Integers INVARIANCE Gauss Gamma Function Li-Function Prime Counting Function Sums of Divisors INVARIANCE PRIMES Twin Primes
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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1050-1062,共13页
The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has... The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta. 展开更多
关键词 ELECTROSTATIC Electron POSITRON COULOMB Force ATTRACTION REPULSION Wave Function Electric Magnetic Radiation Pressure Shell THEOREM 3D Computer Model Quantum
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Dynamic design of a nonlinear energy sink with NiTiNOL-steel wire ropes based on nonlinear output frequency response functions 被引量:7
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作者 Yewei ZHANG Kefan XU +3 位作者 Jian ZANG Zhiyu NI Yunpeng ZHU Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第12期1791-1804,共14页
A novel vibration isolation device called the nonlinear energy sink(NES)with NiTiNOL-steel wire ropes(NiTi-ST)is applied to a whole-spacecraft system.The NiTi-ST is used to describe the damping of the NES,which is cou... A novel vibration isolation device called the nonlinear energy sink(NES)with NiTiNOL-steel wire ropes(NiTi-ST)is applied to a whole-spacecraft system.The NiTi-ST is used to describe the damping of the NES,which is coupled with the modified Bouc-Wen model of hysteresis.The NES with NiTi-ST vibration reduction principle uses the irreversibility of targeted energy transfer(TET)to concentrate the energy locally on the nonlinear oscillator,and then dissipates it through damping in the NES with NiTi-ST.The generalized vibration transmissibility,obtained by the root mean square treatment of the harmonic response of the nonlinear output frequency response functions(NOFRFs),is first used as the evaluation index to analyze the whole-spacecraft system in the future.An optimization analysis of the impact of system responses is performed using different parameters of NES with NiTi-ST based on the transmissibility of NOFRFs.Finally,the effects of vibration suppression by varying the parameters of NiTi-ST are analyzed from the perspective of energy absorption.The results indicate that NES with NiTi-ST can reduce excessive vibration of the whole-spacecraft system,without changing its natural frequency.Moreover,the NES with NiTi-ST can be directly used in practical engineering applications. 展开更多
关键词 NONLINEAR energy sink(NES) vibration isolation NiTiNOL-steel wire ROPE (NiTi-ST) NONLINEAR output frequency response function(NOFRF) ROOT mean square TRANSMISSIBILITY
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Mitochondrial Dysfunctions in Patients with Migraine
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作者 R. Alloush M. Haroun +2 位作者 A. Shalash H. El-Fawal M. Hamdy 《Neuroscience & Medicine》 2019年第4期339-353,共15页
Study Objectives: Migraine is a complex neurovascular disease and is believed to be due to a mixture of genetic and environmental factors. Study design: This was a cross-sectional observational prospective hospital ba... Study Objectives: Migraine is a complex neurovascular disease and is believed to be due to a mixture of genetic and environmental factors. Study design: This was a cross-sectional observational prospective hospital based study conducted on 100 participants. They were divided into two groups;Group A: 50 migrainous patients according to the criteria of the International Classification of Headache Disorders and Group B: 50 healthy subjects both groups were age and sex matched. All subjects underwent a full neurological and psychiatric examination. Full headache evaluation sheet used in headache outpatient clinic in Ain Shams University Hospitals and HIT-6? Headache Impact Test was used. Assay of serum level of N-acetyl-aspartate (NAA) as mitochondrial function marker was done. Results: There was no significant difference between both groups regarding gender, age or age group, marital state, education, residence and special habits. However, there was a statistical significant difference as regards family history of migraine more in patient group. In this study, serum NAA levels in migraine patients were significantly lower than in healthy controls. Decreased NAA level is generally believed to be a sign of reduced neuronal and glial mitochondrial function. Also, migraine with aura patients showed lower NAA levels when compared to migraine without aura subtypes. However, there was no significant correlation was found between NAA serum levels, and gender, age at onset, age group, type of aura, duration of the illness, type of onset of pain, frequent site of pain, time to max severity, severity of attack, and daily functions (social life, work, psychological wellbeing, sleep and cognition). Conclusions: Findings of this study indicate that NAA in serum may be a marker for neuronal dysfunction predisposing to migraine, probably related to the reduced mitochondria function. 展开更多
关键词 MIGRAINE MIGRAINE with AURA MIGRAINE without AURA Mitochondrial Function Marker N-ACETYL-ASPARTATE (NAA) Magnetic Resonance Spectroscopy (MRS) and Liquid Chromatography-Mass SPECTROMETRY (LC/MS)
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Responses of soil microbial communities and functions associated with organic carbon mineralization to nitrogen addition in a Tibetan grassland 被引量:7
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作者 Ruyi LUO Jiafa LUO +4 位作者 Jianling FAN Deyan LIU Jin-Sheng HE Nazia PERVEEN Weixin DING 《Pedosphere》 SCIE CAS CSCD 2020年第2期214-225,共12页
Alpine grasslands with a high soil organic carbon(SOC)storage on the Tibetan Plateau are experiencing rapid climate warming and anthropogenic nitrogen(N)deposition;this is expected to substantially increase the soil N... Alpine grasslands with a high soil organic carbon(SOC)storage on the Tibetan Plateau are experiencing rapid climate warming and anthropogenic nitrogen(N)deposition;this is expected to substantially increase the soil N availability,which may impact carbon(C)cycling.However,little is known regarding how N enrichment influences soil microbial communities and functions relative to C cycling in this region.We conducted a 4-year field experiment on an alpine grassland to evaluate the effects of four different rates of N addition(0,25,50,and 100 kg N ha^-1 year^-1)on the abundance and community structure(phospholipid fatty acids,PLFAs)of microbes,enzyme activities,and community level physiological profiles(CLPP)in soil.We found that N addition increased the microbial biomass C(MBC)and N(MBN),along with an increased abundance of bacterial PLFAs,especially Gram-negative bacterial PLFAs,with a decreasing ratio of Gram-positive to Gram-negative bacteria.The N addition also stimulated the growth of fungi,especially arbuscular mycorrhizal fungi,reducing the ratio of fungi to bacteria.Microbial functional diversity and activity of enzymes involved in C cycling(β-1,4-glucosidase and phenol oxidase)and N cycling(β-1,4-N-acetyl-glucosaminidase and leucine aminopeptidase)increased after N addition,resulting in a loss of SOC.A meta-analysis showed that the soil C/N ratio was a key factor in the response of oxidase activity to N amendment,suggesting that the responses of soil microbial functions,which are linked to C turnover relative to N input,primarily depended upon the soil C/N ratio.Overall,our findings highlight that N addition has a positive influence on microbial communities and their associated functions,which may reduce soil C storage in alpine grasslands under global change scenarios. 展开更多
关键词 ALPINE GRASSLAND C cycling C TURNOVER COMMUNITY level physiological profiles(CLPP) enzyme activity MICROBIAL COMMUNITY composition MICROBIAL function N input
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Functionals and Functional Derivatives of Wave Functions and Densities
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作者 A. Gonis 《World Journal of Condensed Matter Physics》 2014年第3期179-199,共21页
It is shown that the process of conventional functional differentiation does not apply to functionals whose domain (and possibly range) is subject to the condition of integral normalization, as is the case with respec... It is shown that the process of conventional functional differentiation does not apply to functionals whose domain (and possibly range) is subject to the condition of integral normalization, as is the case with respect to a domain defined by wave functions or densities, in which there exists no neighborhood about a given element in the domain defined by arbitrary variations that also lie in the domain. This is remedied through the generalization of the domain of a functional to include distributions in the form of , where ?is the Dirac delta function and is a real number. This allows the determination of the rate of change of a functional with respect to changes of the independent variable determined at each point of the domain, with no reference needed to the values of the functional at different functions in its domain. One feature of the formalism is the determination of rates of change of general expectation values (that may not necessarily be functionals of the density) with respect to the wave functions or the densities determined by the wave functions forming the expectation value. It is also shown that ignoring the conditions of conventional functional differentiation can lead to false proofs, illustrated through a flaw in the proof that all densities defined on a lattice are -representable. In a companion paper, the mathematical integrity of a number of long-standing concepts in density functional theory are studied in terms of the formalism developed here. 展开更多
关键词 FUNCTIONAL FUNCTIONAL Derivative FUNCTIONAL Derivative of WAVE functions FUNCTIONAL DERIVATIVES with RESPECT to WAVE functions FUNCTIONAL DERIVATIVES with RESPECT to Density RATE of CHANGE of a FUNCTIONAL RATE of CHANGE of Expectation Values RATE of CHANGE of a WAVE Function
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Complements to the Theory of Higher-Order Types of Asymptotic Variation for Differentiable Functions 被引量:1
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作者 Antonio Granata 《Advances in Pure Mathematics》 2019年第5期434-479,共46页
The purpose of this paper is to add some complements to the general theory of higher-order types of asymptotic variation developed in two previous papers so as to complete our elementary (but not too much!) theory in ... The purpose of this paper is to add some complements to the general theory of higher-order types of asymptotic variation developed in two previous papers so as to complete our elementary (but not too much!) theory in view of applications to the theory of finite asymptotic expansions in the real domain, the asymptotic study of ordinary differential equations and the like. The main results concern: 1) a detailed study of the types of asymptotic variation of an infinite series so extending the results known for the sole power series;2) the type of asymptotic variation of a Wronskian completing the many already-published results on the asymptotic behaviors of Wronskians;3) a comparison between the two main standard approaches to the concept of “type of asymptotic variation”: via an asymptotic differential equation or an asymptotic functional equation;4) a discussion about the simple concept of logarithmic variation making explicit and completing the results which, in the literature, are hidden in a quite-complicated general theory. 展开更多
关键词 HIGHER-ORDER Regularly-Varying functions HIGHER-ORDER Rapidly-Varying functions Smoothly-Varying functions Exponentially-Varying functions Logarithmically-Varying functions ASYMPTOTIC Differential EQUATIONS As-ymptotic Functional EQUATIONS ASYMPTOTIC VARIATION of Wronskians
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Certain Subclasses of Bi-univalent Functions Associated with(u,v)-Chebyshev Polynomials
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作者 Timilehin Gideon Shaba Sibel Yalcin +1 位作者 Gangadharan Murugusundaramoorthy Maslina Darus 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期429-442,共14页
For the new subclass B of the bi-univalent functions constructed with the help of the(u,v)-Chebyshev polynomials of the second type,we get estimates for the first two initial coefficients and upper bounds of the Feket... For the new subclass B of the bi-univalent functions constructed with the help of the(u,v)-Chebyshev polynomials of the second type,we get estimates for the first two initial coefficients and upper bounds of the Fekete-Szeg o functional. 展开更多
关键词 univalent functions Fekete-Szeg˝o inequalities analytic functions starlike and convex functions of some order bi-univalent functions coefficient bounds SUBORDINATION
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Gap Functions and Error Bounds for Set-Valued Vector Quasi Variational Inequality Problems
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作者 Rachana Gupta Aparna Mehra 《Applied Mathematics》 2017年第12期1903-1917,共15页
One of the classical approaches in the analysis of a variational inequality problem is to transform it into an equivalent optimization problem via the notion of gap function. The gap functions are useful tools in deri... One of the classical approaches in the analysis of a variational inequality problem is to transform it into an equivalent optimization problem via the notion of gap function. The gap functions are useful tools in deriving the error bounds which provide an estimated distance between a specific point and the exact solution of variational inequality problem. In this paper, we follow a similar approach for set-valued vector quasi variational inequality problems and define the gap functions based on scalarization scheme as well as the one with no scalar parameter. The error bounds results are obtained under fixed point symmetric and locally α-Holder assumptions on the set-valued map describing the domain of solution space of a set-valued vector quasi variational inequality problem. 展开更多
关键词 SET-VALUED VECTOR QUASI Variational Inequality Problem GAP FUNCTION Regularized GAP FUNCTION Error Bounds Fixed Point Symmetric MAP α-Holder MAP
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