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Binary Archimedes Optimization Algorithm for Computing Dominant Metric Dimension Problem
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作者 Basma Mohamed Linda Mohaisen Mohammed Amin 《Intelligent Automation & Soft Computing》 2023年第10期19-34,共16页
In this paper,we consider the NP-hard problem of finding the minimum dominant resolving set of graphs.A vertex set B of a connected graph G resolves G if every vertex of G is uniquely identified by its vector of dista... In this paper,we consider the NP-hard problem of finding the minimum dominant resolving set of graphs.A vertex set B of a connected graph G resolves G if every vertex of G is uniquely identified by its vector of distances to the vertices in B.A resolving set is dominating if every vertex of G that does not belong to B is a neighbor to some vertices in B.The dominant metric dimension of G is the cardinality number of the minimum dominant resolving set.The dominant metric dimension is computed by a binary version of the Archimedes optimization algorithm(BAOA).The objects of BAOA are binary encoded and used to represent which one of the vertices of the graph belongs to the dominant resolving set.The feasibility is enforced by repairing objects such that an additional vertex generated from vertices of G is added to B and this repairing process is iterated until B becomes the dominant resolving set.This is the first attempt to determine the dominant metric dimension problem heuristically.The proposed BAOA is compared to binary whale optimization(BWOA)and binary particle optimization(BPSO)algorithms.Computational results confirm the superiority of the BAOA for computing the dominant metric dimension. 展开更多
关键词 Dominant metric dimension archimedes optimization algorithm binary optimization alternate snake graphs
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Gedankenexperiment for Modified ZPE and Planck’s “Constant”, h, in the Beginning of Cosmological Expansion, Partly Due to NLED
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期180-184,共5页
We initially look at a non singular universe representation of entropy, based in part on what was brought up by Muller and Lousto. This is a gateway to bringing up information and computational steps (as defined by Se... We initially look at a non singular universe representation of entropy, based in part on what was brought up by Muller and Lousto. This is a gateway to bringing up information and computational steps (as defined by Seth Lloyd) as to what would be available initially due to a modified ZPE formalism. The ZPE formalism is modified as due to Matt Visser’s alternation of k (maximum) ~ 1/(Planck length), with a specific initial density giving rise to initial information content which may permit fixing the initial Planck’s constant, h, which is pivotal to the setting of physical law. The settings of these parameters depend upon NLED. 展开更多
关键词 ZPE Planck’s constant Gedankenexperiment NLED
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Elementary Fermions: Strings, Planck Constant, Preons and Hypergluons
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期82-100,共19页
Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism ... Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism which is proportional to Planck’s constant. This may be the result of two massless bosons (hypergluons) coupled by a preon (prequark) exchange. It also gives a physical explanation to the origin of the Planck constant, and origin of spin. 展开更多
关键词 FERMIONS Preons Hypergluons Strings Real Fields Planck constant INTERFERENCE SPIN
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ESTIMATE ON THE BLOCH CONSTANT FOR CERTAIN HARMONIC MAPPINGS UNDER A DIFFERENTIAL OPERATOR
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作者 陈洁玲 刘名生 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期295-310,共16页
In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,... In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,using these results,we present better estimations for the Bloch constants of certain harmonic mappings L(f),where f is a K-quasiregular harmonic or open harmonic.Finally,we establish three versions of BlochLandau type theorem for biharmonic mappings of the form L(f).These results are sharp in some given cases and improve the related results of earlier authors. 展开更多
关键词 Bloch-Landau type theorem Bloch constant linear complex operator harmonic mapping biharmonic mapping UNIVALENT
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Enriched Constant Elements in the Boundary Element Method for Solving 2D Acoustic Problems at Higher Frequencies
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作者 Zonglin Li Zhenyu Gao Yijun Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2159-2175,共17页
The boundary element method(BEM)is a popular method for solving acoustic wave propagation problems,especially those in exterior domains,owing to its ease in handling radiation conditions at infinity.However,BEM models... The boundary element method(BEM)is a popular method for solving acoustic wave propagation problems,especially those in exterior domains,owing to its ease in handling radiation conditions at infinity.However,BEM models must meet the requirement of 6–10 elements per wavelength,using the conventional constant,linear,or quadratic elements.Therefore,a large storage size of memory and long solution time are often needed in solving higher-frequency problems.In this work,we propose two new types of enriched elements based on conventional constant boundary elements to improve the computational efficiency of the 2D acoustic BEM.The first one uses a plane wave expansion,which can be used to model scattering problems.The second one uses a special plane wave expansion,which can be used tomodel radiation problems.Five examples are investigated to showthe advantages of the enriched elements.Compared with the conventional constant elements,the new enriched elements can deliver results with the same accuracy and in less computational time.This improvement in the computational efficiency is more evident at higher frequencies(with the nondimensional wave numbers exceeding 100).The paper concludes with the potential of our proposed enriched elements and plans for their further improvement. 展开更多
关键词 Enriched boundary elements constant elements 2D acoustic problems higher frequency
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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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Probing the electric double layer structure at nitrogen-doped graphite electrodes by constant-potential molecular dynamics simulations
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作者 Legeng Yu Nan Yao +5 位作者 Yu-Chen Gao Zhong-Heng Fu Bo Jiang Ruiping Li Cheng Tang Xiang Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期299-305,I0008,共8页
Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium batteries.However,atomic insights into the EDL structures on heteroatom-modified graphite ano... Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium batteries.However,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very lacking.Herein,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an example.An interface model was developed,incorporating the electrode potential and atom electronegativities.As a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic level.Specifically,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,respectively.Such preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+deposition.This CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes. 展开更多
关键词 Lithium batteries Graphite N-DOPING Electric double layer Molecular dynamics constant potential method Electrode potential
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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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Upsilon Constants and Their Usefulness in Planck Scale Quantum Cosmology
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期167-173,共7页
This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper su... This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper summarizes the current state of quantum cosmology with respect to the Flat Space Cosmology (FSC) model. Although the FSC quantum cosmology formulae were published in 2018, they are only rearrangements and substitutions of the other assumptions into the original FSC Hubble temperature formula. In a real sense, this temperature formula was the first quantum cosmology formula developed since Hawking’s black hole temperature formula. A recent development in the last month proves that the FSC Hubble temperature formula can be derived from the Stephan-Boltzmann law. Thus, this Hubble temperature formula effectively unites some quantum developments with the general relativity model inherent in FSC. More progress towards unification in the near-future is expected. 展开更多
关键词 Quantum Cosmology Hubble constant Planck Scale Upsilon constant Flat Space Cosmology Black Holes CMB Temperature ΛCDM Cosmology Quantum Gravity Unification
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The Planck Constant and Its Relation to the Compton Frequency
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2024年第1期168-180,共13页
The Planck constant is considered one of the most important universal constants of physics, and despite all we know much about it, the physical nature of it has not been fully understood. Further investigation and new... The Planck constant is considered one of the most important universal constants of physics, and despite all we know much about it, the physical nature of it has not been fully understood. Further investigation and new perspectives on the Planck constant should therefore be of interest. We demonstrate that the Planck constant also can be directly linked to the Compton frequency of one, which again is divided by the Compton frequency in one kg. If this is right, it means also the Planck constant is linked to quantization of matter, not only energy. However, as we will show the frequency of one when expressed in relation to kg will be observational time dependent. This means the missing mass gap surprisingly both is equal to the Planck mass, which is larger than any known particle and also it is linked to a very small mass that again is equal to what has been suggested as the photon mass in the existing literature. This new view could be an important step forward in understanding the physical nature of the Planck constant as well as the mass gap and even the rest mass of a photon. 展开更多
关键词 Planck constant Compton Frequency ELECTRON Proton Count
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Introducing a 2nd Universal Space-Time Constant Can Explain the Observed Age of the Universe and Dark Energy
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作者 Herman A. van Hoeve 《World Journal of Mechanics》 2024年第2期9-22,共14页
The purpose of this paper is to introduce new theoretical concepts as opposed to accepting the existence of dark entities, such as dark energy. This research sought to introduce a 2<sup>nd</sup> universal ... The purpose of this paper is to introduce new theoretical concepts as opposed to accepting the existence of dark entities, such as dark energy. This research sought to introduce a 2<sup>nd</sup> universal space-time constant, besides having a finite speed constant (speed of light in vacuum c). A finite universal age constant b is introduced. Namely, this paper shows that the changes in the Earth’s anomalistic year duration over time support the hypothesis of the age of the universe correlating with a maximum number of orbital revolutions constant. Neglecting the gravitational influence of other cosmological entities in the proximity of the Earth, the constant maximum number of revolutions is herewith determined solely by the Earth’s orbital revolutions around the Sun. The value of the universal age constant b is calculated to be around 13.8 billion orbital revolutions, derived out of an equation related to the changes in the Earth’s anomalistic year duration over time and the so-called Hubble tension. The above-mentioned calculated value b correlates well with the best fit to measured data of the cosmic microwave background radiation (CMBR) by the Planck spacecraft, the age of the observed universe is measured to be approximately 13.787 ± 0.020 billion years (2018 final data release). Developing a theory with this 2<sup>nd</sup> universal space-time constant b, being covariant with respect to the Lorentz transformations when time spans are large, gives results such as: A confirmation of the measured CMBR value of 13.787 ± 0.020 billion years. Correlating well with the observed expansion rate of the universe (dark energy). The universe’s expansion accelerating over the last four to five billion years. 展开更多
关键词 Anomalistic Year Orbital Revolution Hubble Tension Age of the Universe Cosmological constant Dark Energy Cosmic Microwave Background
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A Solution to the Cosmological Constant Problem Using the Holographic Principle (A Brief Note)
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期159-166,共8页
This paper integrates a quantum conception of the Planck epoch early universe with FSC model formulae and the holographic principle, to offer a reasonable explanation and solution of the cosmological constant problem.... This paper integrates a quantum conception of the Planck epoch early universe with FSC model formulae and the holographic principle, to offer a reasonable explanation and solution of the cosmological constant problem. Such a solution does not appear to be achievable in cosmological models which do not integrate black hole formulae with quantum formulae such as the Stephan-Boltzmann law. As demonstrated herein, assuming a constant value of Lambda over the great span of cosmic time appears to have been a mistake. It appears that Einstein’s assumption of a constant, in terms of vacuum energy density, was not only a mistake for a statically-balanced universe, but also a mistake for a dynamically-expanding universe. 展开更多
关键词 Quantum Cosmology Planck Scale Cosmological constant Black Holes Holographic Principle Flat Space Cosmology AdS-CFT ER = EPR Cosmology Model
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试论Archimedes的数学思想 被引量:1
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作者 王乃信 吴养会 《西北农林科技大学学报(自然科学版)》 CSCD 北大核心 2003年第2期181-184,共4页
依据 Archimedes的数学贡献 ,尤其是 Archimedes在求抛物线弓形面积时所创立的方法 ,分析了Archim edes的数学思想 ,认为 Archimedes既善于进行巧妙的物理论证 ,又善于进行严格的数学论证。由Archim edes的数学思想得到的启示是 :巧妙... 依据 Archimedes的数学贡献 ,尤其是 Archimedes在求抛物线弓形面积时所创立的方法 ,分析了Archim edes的数学思想 ,认为 Archimedes既善于进行巧妙的物理论证 ,又善于进行严格的数学论证。由Archim edes的数学思想得到的启示是 :巧妙的物理论证是科学发现的重要方法 ;严格的数学论证是确立结论的必需步骤 ;要精选若干基本原理 ,作为论证的基础 ;要献身科学真理 ,不为俗世需求所动摇。 展开更多
关键词 archimedes 数学思想 物理论证 数学论证 抛物线弓形面积 古希腊
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结构参数对二维Archimedes A7晶格光子晶体禁带的影响 被引量:1
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作者 杨毅彪 王伟军 +2 位作者 费宏明 梁伟 王云才 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2012年第4期306-310,共5页
利用平面波展开法对空气背景中介质圆柱和方柱构造的二维Archimedes A7晶格光子晶体的禁带结构随介质折射率、填充比的变化关系进行了研究,并进一步计算了介质方柱的旋转角度对完全光子禁带宽度的影响.研究发现,介质圆柱构造的Archimede... 利用平面波展开法对空气背景中介质圆柱和方柱构造的二维Archimedes A7晶格光子晶体的禁带结构随介质折射率、填充比的变化关系进行了研究,并进一步计算了介质方柱的旋转角度对完全光子禁带宽度的影响.研究发现,介质圆柱构造的Archimedes A7晶格结构在介质柱折射率最低为n=2.40时出现完全光子禁带,当n=2.60时禁带宽度达到最大值.介质方柱构造的Archimedes A7晶格结构在介质柱折射率n=3.80时完全禁带宽度达到最大值,且随着折射率的增加禁带宽度变化很小;在介质方柱折射率恒定情况下,其最大禁带宽度与旋转角度无关,但旋转后出现完全禁带的填充比范围明显扩大. 展开更多
关键词 光子晶体 平面波展开法 archimedes A7晶格 完全光子禁带
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一类特殊的非Archimedes序域其构造 被引量:1
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作者 汪芳庭 《南京大学学报(数学半年刊)》 CAS 2001年第1期85-90,共6页
本文讨论了一类特殊的非Archimedes序列,这种序域可用来以简单而自然的方法定义实数,这种序域的构造方式也是自然的,自由然数集N的一种特殊保真扩张模型N出发,使用通常的分数程序来构造,本文在讨论N的保真扩张的一般方法基础上着... 本文讨论了一类特殊的非Archimedes序列,这种序域可用来以简单而自然的方法定义实数,这种序域的构造方式也是自然的,自由然数集N的一种特殊保真扩张模型N出发,使用通常的分数程序来构造,本文在讨论N的保真扩张的一般方法基础上着重讨论相论容方程组方法与超滤方法。 展开更多
关键词 archimedes序域 算术模型 相容方程组 超滤方法 保真扩张 模型理论 转换原理
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Archimedes螺线盘转动问题的差分处理
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作者 管立 俞琳 《曲阜师范大学学报(自然科学版)》 CAS 2000年第4期52-54,共3页
所计算的匀质可燃Archimedes螺线盘 ,是一个在水平支撑面上发生燃喷并做定轴转动的变质量力学系统 .采用差分方法对其进行了有关计算 。
关键词 archimedes螺线盘 力矩 力速度 变质量动力学
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二维介质柱型Archimedes(4,8^2)复式晶格光子晶体禁带特性研究 被引量:2
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作者 韩昌盛 杨毅彪 +3 位作者 王云才 费宏明 陈智辉 李祥霞 《光子学报》 EI CAS CSCD 北大核心 2014年第6期58-62,共5页
采用平面波展开法分别模拟了空气背景下由介质圆柱和方柱构造的二维Archimedes(4,82)复式晶格光子晶体的能带结构,讨论了介质柱形状、折射率、填充比和旋转对称性等因素对完全光子禁带的影响.研究发现,当折射率在2.60到5.40之间时,介质... 采用平面波展开法分别模拟了空气背景下由介质圆柱和方柱构造的二维Archimedes(4,82)复式晶格光子晶体的能带结构,讨论了介质柱形状、折射率、填充比和旋转对称性等因素对完全光子禁带的影响.研究发现,当折射率在2.60到5.40之间时,介质圆柱和方柱构造的二维Archimedes(4,82)复式晶格光子晶体都出现了完全光子禁带.随着折射率的增大,最大完全禁带宽度并非随之增大而是存在峰值,介质圆柱型晶格在折射率为2.80时出现峰值;介质方柱型晶格在折射率为2.80和4.40两处出现峰值,且旋转介质方柱能够明显增大禁带宽度,同时存在最佳旋转角度.分析结果表明,在最大完全禁带处,折射率、填充比以及旋转角度等因素的变化对禁带特性的影响很小. 展开更多
关键词 人工晶体 光子带隙 平面波展开法 光子晶体 archimedes晶格 MAXWELL方程 超材料 子器件 光子集成技术
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Archimedes’ Principle Revisited
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作者 Pirooz Mohazzab 《Journal of Applied Mathematics and Physics》 2017年第4期836-843,共8页
Based on Newton’s third law of motion, we present a different but quite general analysis of Archimedes’ principle. This analysis explains the reduction in apparent weight of a submerged object in all cases, regardle... Based on Newton’s third law of motion, we present a different but quite general analysis of Archimedes’ principle. This analysis explains the reduction in apparent weight of a submerged object in all cases, regardless of its position in the fluid. We also study the case in which the object rests on the bottom of the container where the net hydrostatic force on it is downward, and explain where in this case the reduction in the apparent weight comes from. 展开更多
关键词 archimedes’ PRINCIPLE BUOYANCY APPARENT WEIGHT
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A New Physical Interpretation of Archimedes’ Principle
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作者 Giancarlo Cavazzini 《Journal of Applied Mathematics and Physics》 2018年第1期215-223,共9页
The interpretation of the equilibrium of a solid body floating on the surface of a liquid body is well known as the “Archimedes’ Principle”. Presently, the equilibrium of the solid body is interpreted as the result... The interpretation of the equilibrium of a solid body floating on the surface of a liquid body is well known as the “Archimedes’ Principle”. Presently, the equilibrium of the solid body is interpreted as the result of the concurrence of two mechanical actions which are equivalent and opposite: the “weight” of the body, directed downwards, and the “Archimedes’ force” having a magnitude equivalent to the weight of the volume of liquid displaced by the volume of the body immersed in the liquid, directed upwards. We show arguments proving that this interpretation is not a correct physical interpretation. The same arguments show that a new different interpretation is a correct one. The new interpretation is based on the hypothesis that the “weight” of a body immersed in a body-medium is proportional to the volume of the body immersed in the body-medium and to the difference in density between the matter of the body and the matter of the body-medium. Accordingly, if a body is completely immersed in a body-medium, there is only one mechanical action on the body. This action may be downwards or upwards, or its magnitude may be zero. In this last case, the body is in equilibrium within the body-medium. 展开更多
关键词 archimedes’ PRINCIPLE BUOYANCY DENSITY WEIGHT
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Investigation of Physical and Numerical Model of Archimedes Screw Turbine
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作者 Omar Sulaiman Abdullah Wissam Hashim Khalil +1 位作者 Ammar Hatem Kamel Amir J. Shareef 《Journal of Power and Energy Engineering》 2020年第10期26-42,共17页
Archimedes screw turbines have been developed as they work with a low head with high efficiency, where flow energy can be exploited in small rivers, streams, regulators and others. The power can be produced using Arch... Archimedes screw turbines have been developed as they work with a low head with high efficiency, where flow energy can be exploited in small rivers, streams, regulators and others. The power can be produced using Archimedes turbines and depends on some parameters including the number of blades, flow, and angle of the shaft inclination and the length of the pitch. A physical and numerical model ha<span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> been developed to determine the performance of the Archimedes turbine on the Ramadi Dam in Iraq. The physical model was made of stainless steel with the following parameters (length 1000</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mm, pitch 70</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mm, diameter ratio 0.536, inclination angles 30</span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">, 35</span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">, 40</span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">, 45</span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">). Work was carried out on different flow rates and inclination angles. The experimental results showed that the highest efficiency was 81.4% at 35</span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;"> inclination angle and a flow rate of 1.12 l/s</span><span style="font-family:Verdana;">;</span><span style="font-family:Verdana;"> the maximum power of 9.03 watts was at a 45</span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;"> inclination angle and a flow rate of 2.065 l/s and 72% efficiency. Also, the impact of the pitch and the number of blades were studied</span><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">The results show that torque is increase with an increase in the pitch length, and torque is decreased with increase in several blades. The numerical results showed that the using of two blades led to a greater power produced. The comparison of the numerical and experimental results showed a good agreement, also the comparison with the published data showed a good agreement. As a final result the Archimedes screw has many positive points making it a good potential candidate. The results that emerged show the possibility of using this type of turbine in the Euphrates River in Anbar Governorate—Iraq, as the province is characterized by the presence of many regulators on the river in which turbines can be employed.</span> 展开更多
关键词 archimedes Screw Turbine Physical Model Small Hydropower Station CFD Low Head Turbine
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