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New Approach to Synchronize General Relativity and Quantum Mechanics with Constant “K”-Resulting Dark Matter as a New Fundamental Force Particle
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作者 Siva Prasad Kodukula 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期292-302,共11页
Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction a... Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction and expansion forces of space time. According to this, the space time with Planck diameter is a flat space time. This is the only diameter of space time that can be used as signal transformation in special relativity. This space time diameter defines the fundamental force which belongs to that space time. In quantum mechanics, this space time diameter is only the quantum of space which belongs to that particular fundamental force. Einstein’s general relativity equation and Planck parameters of quantum mechanics have been written in terms of equations containing a constant “K”, thus found a new equation for transformation of general relativity space time in to quantum space time. In this process of synchronization, there is a possibility of a new fundamental force between electromagnetic and gravitational forces with Planck length as its space time diameter. It is proposed that dark matter is that fundamental force carrying particle. By grand unification equation with space-time diameter, we found a coupling constant as per standard model “α<sub>s</sub>” for that fundamental force is 1.08 × 10<sup>-23</sup>. Its energy calculated as 113 MeV. A group of experimental scientists reported the energy of dark matter particle as 17 MeV. Thorough review may advance science further. 展开更多
关键词 general Relativity Quantum Mechanics Space Time Dark Matter A New Fundamental constant “K”
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ASYMPTOTIC EQUIVALENCE OF ALTERNATELY ADVANCED AND DELAYED DIFFERENTIAL SYSTEMS WITH PIECEWISE CONSTANT GENERALIZED ARGUMENTS 被引量:1
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作者 Kuo-Shou CHIU 《Acta Mathematica Scientia》 SCIE CSCD 2018年第1期220-236,共17页
In this paper, we investigate the existence, uniqueness and the asymptotic equiv- alence of a linear system and a perturbed system of differential equations with piecewise alternately advanced and retarded argument of... In this paper, we investigate the existence, uniqueness and the asymptotic equiv- alence of a linear system and a perturbed system of differential equations with piecewise alternately advanced and retarded argument of generalized type (DEPCAG). This is based in the study of an equivalent integral equation with Cauchy and Green matrices type and in a solution of a DEPCAG integral inequality of Gronwall type. Several examples are also given to show the feasibility of results. 展开更多
关键词 piecewise constant argument of generalized type hybrid equations EQUIVALENCE asymptotic behavior Gronwall's inequality
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Coherence Based Sufficient Condition for Support Recovery Using Generalized Orthogonal Matching Pursuit
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作者 Aravindan Madhavan Yamuna Govindarajan Neelakandan Rajamohan 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期2049-2058,共10页
In an underdetermined system,compressive sensing can be used to recover the support vector.Greedy algorithms will recover the support vector indices in an iterative manner.Generalized Orthogonal Matching Pursuit(GOMP)... In an underdetermined system,compressive sensing can be used to recover the support vector.Greedy algorithms will recover the support vector indices in an iterative manner.Generalized Orthogonal Matching Pursuit(GOMP)is the generalized form of the Orthogonal Matching Pursuit(OMP)algorithm where a number of indices selected per iteration will be greater than or equal to 1.To recover the support vector of unknown signal‘x’from the compressed measurements,the restricted isometric property should be satisfied as a sufficient condition.Finding the restricted isometric constant is a non-deterministic polynomial-time hardness problem due to that the coherence of the sensing matrix can be used to derive the sufficient condition for support recovery.In this paper a sufficient condition based on the coherence parameter to recover the support vector indices of an unknown sparse signal‘x’using GOMP has been derived.The derived sufficient condition will recover support vectors of P-sparse signal within‘P’iterations.The recovery guarantee for GOMP is less restrictive,and applies to OMP when the number of selection elements equals one.Simulation shows the superior performance of the GOMP algorithm compared with other greedy algorithms. 展开更多
关键词 Compressed sensing restricted isometric constant generalized orthogonal matching pursuit support recovery recovery guarantee COHERENCE
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GENERALIZED FATIGUE CONSTANT LIFE CURVE AND TWO-DIMENSIONAL PROBABILITY DISTRIBUTION OF FATIGUE LIMIT
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作者 熊峻江 武哲 高镇同 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第10期1188-1193,共6页
According to the traditional fatigue constant life curve, the concept and the universal expression of the generalized fatigue constant life curve were proposed. Then, on the basis of the optimization method of the cor... According to the traditional fatigue constant life curve, the concept and the universal expression of the generalized fatigue constant life curve were proposed. Then, on the basis of the optimization method of the correlation coefficient, the parameter estimation formulas were induced and the generalized fatigue constant life curve with the reliability level p was given. From P-S-a-S-m curve, the two-dimensional probability distribution of the fatigue limit was derived. After then, three se, of tests of LY11 CZ corresponding to the different average stress were carried out in terms of the two-dimensional up-down method. Finally, the methods are used to analyze the test results, and it is found that the analyzed results with the high precision may be obtained. 展开更多
关键词 fatigue limit generalized constant life curve two-dimensional up-down method
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Bulk Viscous Anisotropic Cosmological Models with Generalized Chaplygin Gas with Time Varying Gravitational and Cosmological Constants
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作者 Shubha Kotambkar Gyan Prakash Singh Rupali Kelkar 《Natural Science》 2015年第6期312-323,共12页
This paper is devoted to studying the generalized Chaplygin gas models in Bianchi type III space- time geometry with time varying bulk viscosity, cosmological and gravitational constants. We are considering the condit... This paper is devoted to studying the generalized Chaplygin gas models in Bianchi type III space- time geometry with time varying bulk viscosity, cosmological and gravitational constants. We are considering the condition on metric potential . Also to obtain deterministic models we have considered physically reasonable relations like , and the equation of state for generalized Chaplygin gas given by . A new set of exact solutions of Einstein’s field equations has been obtained in Eckart theory, truncated theory and full causal theory. Physical behaviour of the models has been discussed. 展开更多
关键词 Bianchi Type III BULK VISCOSITY COSMOLOGICAL constant GRAVITATIONAL constant generalized Chaplygin Gas
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ON A GENERALIZED GEOMETRIC CONSTANT AND SUFFICIENT CONDITIONS FOR NORMAL STRUCTURE IN BANACH SPACES
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作者 Mina DINARVAND 《Acta Mathematica Scientia》 SCIE CSCD 2017年第5期1209-1220,共12页
In this paper, we introduce a new geometric constant C;(a, X) of a Banach space X, which is closely related to the generalized von Neumann-Jordan constant and analyze some properties of the constant. Subsequently, w... In this paper, we introduce a new geometric constant C;(a, X) of a Banach space X, which is closely related to the generalized von Neumann-Jordan constant and analyze some properties of the constant. Subsequently, we present several sufficient conditions for normal structure of a Banach space in terms of this new constant, the generalized James constant, the generalized Garc′?a-Falset coefficient and the coefficient of weak orthogonality of Sims. Our main results of the paper generalize some known results in the recent literature. 展开更多
关键词 uniform normal structure generalized Garc′?a-Falset coefficient coefficient of weak orthogonality constant CN Jp(a X) generalized James constant
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The Extremal Universe Exact Solution from Einstein’s Field Equation Gives the Cosmological Constant Directly
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作者 Espen Gaarder Haug 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期386-397,共12页
Einstein’s field equation is a highly general equation consisting of sixteen equations. However, the equation itself provides limited information about the universe unless it is solved with different boundary conditi... Einstein’s field equation is a highly general equation consisting of sixteen equations. However, the equation itself provides limited information about the universe unless it is solved with different boundary conditions. Multiple solutions have been utilized to predict cosmic scales, and among them, the Friedmann-Lemaître-Robertson-Walker solution that is the back-bone of the development into today standard model of modern cosmology: The Λ-CDM model. However, this is naturally not the only solution to Einstein’s field equation. We will investigate the extremal solutions of the Reissner-Nordström, Kerr, and Kerr-Newman metrics. Interestingly, in their extremal cases, these solutions yield identical predictions for horizons and escape velocity. These solutions can be employed to formulate a new cosmological model that resembles the Friedmann equation. However, a significant distinction arises in the extremal universe solution, which does not necessitate the ad hoc insertion of the cosmological constant;instead, it emerges naturally from the derivation itself. To the best of our knowledge, all other solutions relying on the cosmological constant do so by initially ad hoc inserting it into Einstein’s field equation. This clarification unveils the true nature of the cosmological constant, suggesting that it serves as a correction factor for strong gravitational fields, accurately predicting real-world cosmological phenomena only within the extremal solutions of the discussed metrics, all derived strictly from Einstein’s field equation. 展开更多
关键词 general Relativity Theory Cosmological constant Extremal Solution Reissner-Nordström KERR Kerr-Newman
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Planck Quantised General Relativity Theory Written on Different Forms
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2024年第6期2281-2301,共21页
This paper is a brief review of our work on the Planck quantized version of general relativity theory. It demonstrates several straightforward methods to rewrite the same equations that we have already presented in ot... This paper is a brief review of our work on the Planck quantized version of general relativity theory. It demonstrates several straightforward methods to rewrite the same equations that we have already presented in other papers. We also explore a relatively new general relativity-inspired field equation based on the original Newtonian mass, which is very different from today’s kilogram mass. Additionally, we examine two other field equations based on collision space-time, where both energy and matter can be described simply as space and time. We are thereby fulfilling Einstein’s dream of a theory where energy and mass are not needed, or are just aspects of space and time. If this is extended beyond the 4-dimensional space-time formalism of general relativity theory to a 6-dimensional framework with 3 space dimensions and 3 time dimensions, this ultimately reveals that they are two sides of the same coin. In reality, it is a three-dimensional space-time theory, where space and time are just two sides of the same coin. 展开更多
关键词 general Relativity Planck Quantization Compton Frequency Composite constant G Quantum Gravity Unification Collision Space-Time
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Banach空间中的广义Dunkl-Williams常数及其性质
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作者 张敬信 《应用泛函分析学报》 2016年第2期189-196,共8页
本文给出了广义Dunkl-Williams常数与一些著名几何常数例如凸系数、光滑系数、James常数之间的关系,从而得到一些蕴含不动点性质的充分条件,另外通过广义Dunkl-Williams常数的上下界的估计给出了Banach空间一致非方的刻画.
关键词 广义dunkl-williams常数 凸系数 光滑系数 James常数 一致非方 不动点 性质
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An Inventory Model for Deteriorating Items with Generalised Exponential Decreasing Demand, Constant Holding Cost and Time-Varying Deterioration Rate 被引量:2
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作者 Isiyaku Aliyu Babangida Sani 《American Journal of Operations Research》 2018年第1期1-16,共16页
In this present paper, an inventory model with a generalised exponential decreasing demand is considered. A numerical example is used to illustrate the application of the model. Sensitivity analysis of the optimal sol... In this present paper, an inventory model with a generalised exponential decreasing demand is considered. A numerical example is used to illustrate the application of the model. Sensitivity analysis of the optimal solution with respect to various parameters is carried out to see the effect of parameter changes on the solution. 展开更多
关键词 Linear DETERIORATION generalize EXPONENTIAL DECREASING DEMAND Inventory constant HOLDING Cost
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J-Resolution Fields of Generalized Literals of L_(14)P(X)
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作者 李晓冰 徐扬 《Journal of Southwest Jiaotong University(English Edition)》 2007年第4期357-360,共4页
To deal with automated reasoning of linguistic truth-valued lattice-valued logic system, a lattice implication algebra with 14 elements, L14, was defined, and the J-resolution fields of constants, propositional variab... To deal with automated reasoning of linguistic truth-valued lattice-valued logic system, a lattice implication algebra with 14 elements, L14, was defined, and the J-resolution fields of constants, propositional variables and some generalized literals of L14P(X), which is a lattice-valued propositional logic system with truth-values in L14, were discussed. There are 4 filters in L14. For any constant a not belonging to J, a and g (generalized literal of L14P(X)) form a J-resolution pair. For a propositional variable x, if x belongs to J and g does not belong to J, then x and g form a J-resolution pair. 展开更多
关键词 constant Propositional variable generalized literal Filter Resolution field
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Application of longitudinal generalized magneto-optical ellipsometry in magnetic ultrathin films
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作者 王晓 连洁 +6 位作者 张福军 高尚 陈延学 于晓红 李萍 王英顺 孙兆宗 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期417-422,共6页
The longitudinal generalized magneto-optical ellipsometry (GME) method is extended to the measurement of three- layer ultrathin magnetic films. In this work, the theory of the reflection matrix is introduced into th... The longitudinal generalized magneto-optical ellipsometry (GME) method is extended to the measurement of three- layer ultrathin magnetic films. In this work, the theory of the reflection matrix is introduced into the GME measurement to obtain the reflective matrix parameters of ultrathin multilayer magnetic films with different thicknesses. After that, a spectroscopic ellipsometry is used to determine the optical parameter and the thickness of every layer of these samples, then the magneto-optical coupling constant of the multilayer magnetic ultrathin film can be obtained. After measurements of a series of ultrathin Fe films, the results show that the magneto-optical coupling constant Q is independent of the thickness of the magnetic film. The magneto-optical Kerr rotations and ellipticity are measured to confirm the validity of this experiment. Combined with the optical constants and the Q constant, the Kerr rotations and ellipticity are calculated in theory. The results show that the theoretical curve fits very well with the experimental data. 展开更多
关键词 generalized magneto-optical ellimpsometry magneto-optical coupling constant
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Minkowskian Solution of General Relativity with Cosmological Constant and the Accelerating Universe
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作者 Yves Pierseaux 《Journal of Modern Physics》 2014年第16期1725-1732,共8页
A Minkowskian solution of the equation of General Relativity (as written by Einstein in 1915) is trivial because it simply means that both members of the equation are equal to zero. However, if alternatively, one cons... A Minkowskian solution of the equation of General Relativity (as written by Einstein in 1915) is trivial because it simply means that both members of the equation are equal to zero. However, if alternatively, one considers the complete equation with a non-zero constant Λ (Einstein 1917), a Minkowskian solution is no longer trivial because it amounts to impose a constraint on the right hand side of the equation (i.e. a non-null stress-energy tensor). If furthermore one identifies (as usual) this tensor to the one of a perfect fluid, one finds that this fluid has a positive energy density and a negative pressure that depend on the three constants of the equation (i.e. gravitational constant G, cosmological constant Λ and velocity of light c). When doing that (§1), one has to consider the “Minkowskian Vacuum” as a physical object of GR (an enigmatic non-baryonic Minkowskian fluid). Can one build a model of this object on the basis of a dynamical equilibrium between the effective gravitational attraction due to the positive energy density versus the negative pressure repulsion? We propose to study such a model, where the (enigmatic) fluid is assumed to exist only in a limited sphere whose surface acts like a “test body” sensitive to the gravitational field created by the fluid. No static equilibrium exists, but a pseudoNewtonian “dynamical equilibrium” (§2) can be reached if the pseudoEuclidean fluid is in state of expansion. Up to there, we have simply constructed a model of an “abstract Universe” (i.e. the limited sphere: There is no fluid outside this sphere!) that gives to a (purely mathematical) constant Λ a concrete physical meaning. We discover finally that our expanding fluid has not only dynamical (gravitational) properties (§3) but also optical properties that are connected with Doppler Redshift (§4). Remembering that recent observations in Cosmology indicate that the “real Universe” seems to be “Flat” and in “Accelerated Expansion”;remembering also (after all) that the archetypal Flat Universe is simply a Minkowskian Universe, we logically wonder if the unexpected Minkowskian global solution, could not be also a significant cosmological model (conclusion). 展开更多
关键词 general RELATIVITY Minkowskian FLUID COSMOLOGICAL constant Accelerating UNIVERSE
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超级电容参与风电调频的动态响应优化策略
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作者 黎静华 敖国进 +1 位作者 宋诚鑫 兰飞 《电力系统自动化》 EI CSCD 北大核心 2024年第17期46-55,共10页
随着风电渗透率的不断提高,电力系统逐步呈现低惯量的特征。低惯量系统在故障时的频率变化率(RoCoF)和最大频率偏差显著增大,传统频率控制方法效果减弱,频率的安全、稳定面临挑战。针对上述问题,先于一次调频动作的快速频率响应(FFR)已... 随着风电渗透率的不断提高,电力系统逐步呈现低惯量的特征。低惯量系统在故障时的频率变化率(RoCoF)和最大频率偏差显著增大,传统频率控制方法效果减弱,频率的安全、稳定面临挑战。针对上述问题,先于一次调频动作的快速频率响应(FFR)已成为解决低惯量系统频率稳定问题的重要手段。首先,建立风-火-储电力系统频率响应模型,分析FFR调频资源对低惯量系统频率响应的影响;其次,基于模糊逻辑推理,提出了一种超级电容参与风电调频的储能动态响应优化策略以控制储能,使其能够动态响应系统频率变化,在频率跌落期遏制频率跌落,在频率恢复期调控储能恢复功率以维持荷电状态稳定;最后,对提出的控制策略进行仿真验证。仿真结果表明,所提策略能够利用超级电容快速动态响应系统频率变化,从而为低惯量系统提供功率支撑,弥补风电调频的不足,相较传统的风电机组虚拟惯量控制策略,在减小最大RoCoF及抑制最大频率偏差效果上均有大幅提升。 展开更多
关键词 低惯量系统 快速频率响应 超级电容 风力发电 模糊逻辑控制 频率调节 惯性常数
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基于恒电容表面络合模型预测土壤中As(Ⅴ)吸附行为研究
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作者 薛沁 李焱 +1 位作者 郁何敏 王玉军 《农业环境科学学报》 CAS CSCD 北大核心 2024年第2期278-284,共7页
吸附是控制As在土壤中迁移的重要过程之一,为了预测As(Ⅴ)在土壤中的吸附过程,使用恒电容表面络合模型(CCM)模拟As(Ⅴ)在土壤中的吸附行为,获取As(Ⅴ)在土壤上吸附的表面络合常数,建立土壤基本理化性质(pH、有机质、碳酸钙、无定形铁/铝... 吸附是控制As在土壤中迁移的重要过程之一,为了预测As(Ⅴ)在土壤中的吸附过程,使用恒电容表面络合模型(CCM)模拟As(Ⅴ)在土壤中的吸附行为,获取As(Ⅴ)在土壤上吸附的表面络合常数,建立土壤基本理化性质(pH、有机质、碳酸钙、无定形铁/铝/锰、总铁)与As(Ⅴ)表面络合参数的线性回归模型,以阐明As在土壤中吸附的主控因子。结果显示,As(Ⅴ)在不同类型的土壤中表现出不同的吸附特征,恒电容模型能够很好地模拟As(Ⅴ)在不同pH下的吸附特性(R^(2)为0.71~0.96),通过CCM模型拟合得到As(Ⅴ)在土壤表面的3个表面络合常数,绝大部分土壤lg K_(1)比lg K_(2)和lg K_(3)的值要大,说明As(Ⅴ)在土壤中的吸附相较于单齿络合物更偏向于形成双齿双核的络合物。As(Ⅴ)表面络合常数与土壤性质间的回归分析结果表明,As(Ⅴ)表面络合常数主要受土壤pH和无定形铁、无定形锰含量的影响。为了进一步验证上述线性模型的普适性,利用文献数据中土壤性质数据预测不同土壤上As(Ⅴ)的表面络合常数,并结合CCM模型预测了As(Ⅴ)在文献土壤中的吸附量,预测值和实测值具有很好的相关性,说明该模型具有一定的普适性。 展开更多
关键词 表面络合模型 As(Ⅴ) 吸附 恒电容模型 广义复合模式
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新型电力系统点对网惯性支撑能力在线监测方法
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作者 邓小宇 刘牧阳 +3 位作者 常喜强 南东亮 莫若 陈俊儒 《上海交通大学学报》 EI CAS CSCD 北大核心 2024年第9期1390-1399,共10页
准确及时地监测低惯量新型电力系统中聚合电源汇集点对电网的惯性支撑能力,对于提升系统安全、稳定、经济化运行具有重要意义.为阐明点对网的惯性支撑能力在线监测方法的基本原理,首先对以摇摆方程为基础的电力系统等效惯性常数定义及... 准确及时地监测低惯量新型电力系统中聚合电源汇集点对电网的惯性支撑能力,对于提升系统安全、稳定、经济化运行具有重要意义.为阐明点对网的惯性支撑能力在线监测方法的基本原理,首先对以摇摆方程为基础的电力系统等效惯性常数定义及现有在线监测方法进行回顾;然后,为弥补现有在线监测方法在准确性上的欠缺,创新性地提出基于回归法的等效惯性常数辨识方法,并与在线惯量监测方法结合,构建基于同步相量测量单元的新型电力系统点对网惯性支撑能力在线监测的系统性方法;最后,利用改进的新英格兰10机39节点系统仿真分析,论证了该惯性支撑能力在线监测方法的实时性、准确性及其对新型电力系统的适用性. 展开更多
关键词 新型电力系统 惯量监测 虚拟同步电机 等效惯性常数
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A Set of Almost Automorphic Functions and Applications
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作者 William Dimbour Vincent Valmorin 《Applied Mathematics》 2024年第1期9-21,共13页
For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-al... For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-almost automorphic functions, we give sufficient conditions of the existence and uniqueness of almost automorphic solutions of a differential equation with a piecewise constant argument of generalized type. This is done using the Banach fixed point theorem. 展开更多
关键词 Almost Automorphic Functions S-Almost Automorphic Functions Differential Equation with Piecewise constant Argument of generalized Type
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子空间干扰加高斯杂波背景下基于GLRT的斜对称方向检测器设计
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作者 田华飞 魏广芬 +2 位作者 简涛 周战 罗沅 《海军航空大学学报》 2024年第2期224-234,共11页
文章研究了背景为子空间干扰加高斯杂波的距离扩展目标方向检测问题。杂波是均值为零协方差矩阵未知但具有斜对称特性的高斯杂波,目标与干扰分别通过具备斜对称特性的目标子空间和干扰子空间描述。针对方向检测问题,利用上述斜对称性,... 文章研究了背景为子空间干扰加高斯杂波的距离扩展目标方向检测问题。杂波是均值为零协方差矩阵未知但具有斜对称特性的高斯杂波,目标与干扰分别通过具备斜对称特性的目标子空间和干扰子空间描述。针对方向检测问题,利用上述斜对称性,根据广义似然比检验(Generalized Likeli-hood Ratio Test,GLRT)准则的一步与两步设计方法,设计了基于GLRT的一步法与两步法的距离扩展目标方向检测器。通过理论推导证明了这2种检测器相对于未知杂波协方差矩阵都具有恒虚警率。对比相同背景下已有检测器,特别是在辅助数据有限的场景下,文章提出的2个检测器表现出了优越的检测性能。 展开更多
关键词 广义似然比检验 距离扩展目标 方向检测器 斜对称 恒虚警率
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Density Functional Calculations of the Mechanical, Electronic and Dynamical Properties of Antiperovskite Ca3BO (B = Pb, Ge, Sn)
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作者 Phillip Wilfsen Otieno Nyawere 《Open Journal of Microphysics》 2024年第1期1-12,共12页
An analysis of mechanical, electronic and dynamical properties of antiperovskite Ca<sub>3</sub>BO (B = Pb, Ge, Sn) in cubic phase space group Pm-3m (221) has been studied using first principle density func... An analysis of mechanical, electronic and dynamical properties of antiperovskite Ca<sub>3</sub>BO (B = Pb, Ge, Sn) in cubic phase space group Pm-3m (221) has been studied using first principle density functional theory (DFT). Ground state energy computation was done using the Projector Augmented Wave (PAW) Pseudo Potentials and the Plane Wave (PW) basis set. The Generalized Gradient Approximation (GGA) was used for the exchange correlation. The open source code QUANTUM ESPRESSO (QE) was used in this study in which plane wave basis sets are applied for the expansion of the electronic structure wave function. Thermo_pw as a post-processing code was used for the computation of mechanical properties including bulk modulus and elastic constants with their derivatives. The lattice parameters are here calculated to be 4.87 Å, 4.86 Å and 4.84 Å for Ca<sub>3</sub>BO (B = Pb, Ge, Sn) respectively which compares well with other works. This also shows that the three crystals are similar in size and in most of their properties. In addition to this, projected density of states and band structure are also computed both showing that these materials are of semi-metallic nature and are stable in cubic phase. Phonon modes at gamma are also reported. 展开更多
关键词 ANTIPEROVSKITE Elastic constants generalized Gradient Approximation
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大规模新能源接入的电力系统惯量缺失机理及惯量水平评估
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作者 李逸欣 吴伟杰 +4 位作者 张伊宁 郑敏嘉 娄源媛 庾力维 蔡颖倩 《南方能源建设》 2024年第5期132-139,共8页
[目的]为满足我国“30、60”的碳达峰、碳中和目标,大量风电、光伏等新能源发电通过变流器接口接入系统,以替代燃煤同步机组出力,极大地影响了电力系统惯量及相应的频率动态特性。[方法]首先分析传统电力系统惯量运动方程及传统发电机... [目的]为满足我国“30、60”的碳达峰、碳中和目标,大量风电、光伏等新能源发电通过变流器接口接入系统,以替代燃煤同步机组出力,极大地影响了电力系统惯量及相应的频率动态特性。[方法]首先分析传统电力系统惯量运动方程及传统发电机扰动后的惯量响应阶段的功频动态过程,再定性讨论了大规模新能源接入后的系统惯性缺失机理。[结果]讨论了国内外常用的集中惯性评价指标,阐述了用系统的总动能和惯性常数作为电网惯性评价指标的依据。[结论]结合某省级电网的新能源开发和消纳的规划,对该省级电网的惯量水平进行了工程化评估,提出了相应的惯量提升建议。 展开更多
关键词 新能源发电 电力系统惯量 频率 惯量常数
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