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The Boltzmann Constant: Evaluation of Measurement Relative Uncertainty Using the Information Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2019年第3期486-504,共19页
The purpose of this work is to prove that only by applying a theoretically sound information approach to developing a model for measuring the Boltzmann constant, one can justify and calculate the value of the required... The purpose of this work is to prove that only by applying a theoretically sound information approach to developing a model for measuring the Boltzmann constant, one can justify and calculate the value of the required relative uncertainty. A dimensionless parameter (comparative uncertainty) was proposed as a universal metric for comparing experimental measurements of Boltzmann constant and simulated data. Examples are given of applying the proposed original method for calculating the relative uncertainty in measuring the Boltzmann constant using an acoustic gas thermometer, dielectric constant gas thermometer, Johnson noise thermometer, Doppler broadening thermometer. The proposed approach is theoretically justified and devoid of the shortcomings inherent in the CODATA concept: a statistically significant trend, a cumulative value of consensus or a statistical control. We tried to show how a mathematical-expert formalism can be replaced by a simple, theoretically grounded postulate on the use of information theory in measurements. 展开更多
关键词 BOLTZMANN constant COMPARATIVE UNCERTAINTY Information-Based APPROACH relative UNCERTAINTY
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Studies of Thermodynamic Properties and Relative Stability of Polybrominated Xanthones by Density Functional Theory 被引量:3
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作者 单刚 李秀菊 +1 位作者 王遵尧 杨郭英 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第2期225-232,共8页
The thermodynamic properties of xanthone(XTH) and 135 polybrominated xanthones(PBXTHs) in the standard state have been calculated at the B3LYP/6-31G* level using Gaussian 03 program.The isodesmic reactions were d... The thermodynamic properties of xanthone(XTH) and 135 polybrominated xanthones(PBXTHs) in the standard state have been calculated at the B3LYP/6-31G* level using Gaussian 03 program.The isodesmic reactions were designed to calculate the standard enthalpy of formation(△fHθ) and standard free energy of formation(△fGθ) of PBXTH congeners.The relations of these thermodynamic parameters with the number and position of Br atom substitution(NPBS) were discussed,and it was found that there exist high correlation between thermodynamic parameters(entropy(Sθ),△fHθ and △fGθ) and NPBS.According to the relative magnitude of their △fGθ,the relative stability order of PBXTH congeners was theoretically proposed.The relative rate constants of formation reactions of PBXTH congeners were calculated,Moreover,the values of molar heat capacity at constant pressure(Cp,m) from 200 to 1000 K for PBXTH congeners were also calculated,and the temperature dependence relation of them was obtained,suggesting very good relationships between Cp,m and temperature(T,T^1 and T^2) for almost all PBXTH congeners. 展开更多
关键词 polybrominated xanthone the number and position of Br atom substitution(NPBS) thermodynamic property relative stability molar heat capacity at constant pressure(Cp m)
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Relative floatability as a criterion for evaluating the separation performance of phosphate from iron 被引量:1
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作者 Azizi Asghar Seyyed Alizade Ganji Seyyed Mohammad 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第3期451-458,共8页
This work was aimed to study the relative floatability of phosphate flotation by means of kinetic analysis.The relative floatability is important to determine how selectively the phosphate is separated from its impuri... This work was aimed to study the relative floatability of phosphate flotation by means of kinetic analysis.The relative floatability is important to determine how selectively the phosphate is separated from its impurities. The effects of pulp pH, solid content, reagents dosage(depressant, collector and co-collector) and conditioning time were investigated on the ratio of the modified rate constant of phosphate to the modified rate constant of iron(relative floatability). The results showed that a large dosage of depressant associated with a low value of collector resulted in a better relative floatability. Increasing the co-collector dosage, conditioning time and pH increased the relative floatability up to a certain value and thereafter resulted in diminishing the relative floatability. Meanwhile, the results indicated that increment of solid concentration increased the relative floatability in range investigated. It was also found that that maximum relative floatability(16.05) could be obtained in pulp pH, 9.32, solid percentage, 30,depressant dosage, 440 g/t, collector dosage, 560 g/t, co-collector dosage, 84.63 g/t and conditioning time,9.43 min. 展开更多
关键词 Phosphate relative floatability Kinetics Rate constant Separation
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The Friendly and Cooperative Relations between the Communist Party of China and Parties in Latin-American Countries Witness Constant Development
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作者 Wu Ju International Department of the Central Committee of the Communist Party of China 《International Understanding》 2003年第2期7-10,共4页
关键词 WITNESS in Development The Friendly and Cooperative relations between the Communist Party of China and Parties in Latin-American Countries Witness constant of
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Physical interpretation of Planck's constant based on the Maxwell theory 被引量:1
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作者 张东才 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第4期87-95,共9页
The discovery of the Planck relation is generally regarded as the starting point of quantum physics.Planck's constant h is now regarded as one of the most important universal constants.The physical nature of h,howeve... The discovery of the Planck relation is generally regarded as the starting point of quantum physics.Planck's constant h is now regarded as one of the most important universal constants.The physical nature of h,however,has not been well understood.It was originally suggested as a fitting constant to explain the black-body radiation.Although Planck had proposed a theoretical justification of h,he was never satisfied with that.To solve this outstanding problem,we use the Maxwell theory to directly calculate the energy and momentum of a radiation wave packet.We find that the energy of the wave packet is indeed proportional to its oscillation frequency.This allows us to derive the value of Planck's constant.Furthermore,we show that the emission and transmission of a photon follows the all-or-none principle.The "strength" of the wave packet can be characterized by ζ,which represents the integrated strength of the vector potential along a transverse axis.We reason that ζ should have a fixed cut-off value for all photons.Our results suggest that a wave packet can behave like a particle.This offers a simple explanation to the recent satellite observations that the cosmic microwave background follows closely the black-body radiation as predicted by Planck's law. 展开更多
关键词 Planck's constant Maxwell's theory de Broglie relation uncertainty principle wave packet PHOTON
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Precise Measurements of the Gravitational Constant: Revaluation by the Information Approach 被引量:2
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2019年第6期1272-1288,共17页
The gravitational constant discovered by Newton is still measured with a relative uncertainty that is several orders of magnitude larger than the relative uncertainty of other fundamental constants. Numerous methods a... The gravitational constant discovered by Newton is still measured with a relative uncertainty that is several orders of magnitude larger than the relative uncertainty of other fundamental constants. Numerous methods are used to measure it. This article discusses the information-oriented approach for analyzing the achievable relative measurement uncertainty, in which the magnitude of the gravitational constant can be considered as plausible. A comparison is made and the advantages and disadvantages of various methods are discussed in terms of the possibility of achieving higher accuracy using a new metric called comparative uncertainty, which was proposed by Brillouin. 展开更多
关键词 GRAVITATIONAL constant COMPARATIVE UNCERTAINTY INFORMATION Theory Modeling relative UNCERTAINTY
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Reciprocity Relation between the Mass Constituents of the Universe and Hardy’s Quantum Entanglement Probability 被引量:2
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作者 Hans Hermann Otto 《World Journal of Condensed Matter Physics》 2018年第2期30-35,共6页
In this short contribution, a reciprocity relation between mass constituents of the universe was explained governed by Hardy’s maximum entanglement probability of φ5 = 0.09017. While well explainable through a set-t... In this short contribution, a reciprocity relation between mass constituents of the universe was explained governed by Hardy’s maximum entanglement probability of φ5 = 0.09017. While well explainable through a set-theoretical argumentation, the relation may also be a consequence of a coupling factor attributed to the normed dimensions of the universe. Also, very simple expressions for the mass amounts were obtained, when replacing the Golden Mean φ by the Archimedes’ constant π. A brief statement was devoted to the similarity between the E-Infinity Theory of El Naschie and the Information Relativity Theory of Suleiman. In addition, superconductivity was also linked with Hardy’s entanglement probability. 展开更多
关键词 UNIVERSE MASS Constituents Golden Mean Archimedes’ constant RECIPROCITY relatION E-INFINITY THEORY Information relativity THEORY Entanglement Superconductivity
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Comment to Guynn’s Fine-Structure Constant Approach 被引量:1
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作者 Hans Hermann Otto 《Journal of Applied Mathematics and Physics》 2022年第9期2796-2804,共9页
Sommerfeld’s fundamental fine-structure constant α once more gives reason to be amazed. This comment is a Chapter of a publication in preparation dealing mainly with golden ratio signature behind Preston Guynn’s fa... Sommerfeld’s fundamental fine-structure constant α once more gives reason to be amazed. This comment is a Chapter of a publication in preparation dealing mainly with golden ratio signature behind Preston Guynn’s famous matter/space approach. As a result we present a relation of α to the galactic velocity , mediated by the circle constant π, which points to an omnipresent importance of this constant and its intrinsic reciprocity pecularity: α ≈ π<sup>2</sup>|β<sub>g</sub>| respectively . The designation fine-structure constant should be replaced simply by Sommerfeld’s constant. We present golden mean-based approximations for α as well as for electron’s charge and mass and connect the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) with |β<sub>g</sub>|. 展开更多
关键词 Structure-Matter Theory Thomas Precession Sommerfeld’ constant Galactic Velocity Reciprocity relation Goldem Mean Gyromagnetic Factor Unification of Science
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Ni-Ga BINARY PHASE RELATIONS AT 700℃
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作者 Wang Cong, Qiao Zhiyu, Xing Xianran and Xie Yun’anDepartment of Physical Chemistry, University of Science and Technology Beijing,Beijing 100083, P. R. China 《中国有色金属学会会刊:英文版》 CSCD 1998年第1期127-132,共6页
NiGaBINARYPHASERELATIONSAT700℃①WangCong,QiaoZhiyu,XingXianranandXieYun’anDepartmentofPhysicalChemistry,Univ... NiGaBINARYPHASERELATIONSAT700℃①WangCong,QiaoZhiyu,XingXianranandXieYun’anDepartmentofPhysicalChemistry,UniversityofSciencean... 展开更多
关键词 Ni-Ga BINARY PHASE relation lattice constant INTERMETALLIC compound
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Study on cipher propertys of constant weight codes
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作者 Lin Bogang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期458-461,共4页
Constant weight code is an important error-correcting control code in communications. Basic structure of constant weight codes for some arriving at Johnson bound, A(n, 2u, w), is presented. Some correlative property... Constant weight code is an important error-correcting control code in communications. Basic structure of constant weight codes for some arriving at Johnson bound, A(n, 2u, w), is presented. Some correlative propertys of the codes, the solution of arriving at Johnson bound, and the results on the couple constant code and some constant weight codes are discussed. The conclusion is verified through four examples. 展开更多
关键词 constant weight code Johnson bound couple relation boundary property combination cipher.
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Phonon dispersion relations of crystalline solids based on LAMMPS package
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作者 Zhiyong Wei Tianhang Qi +1 位作者 Weiyu Chen Yunfei Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第11期395-400,共6页
The phonon dispersion relations of crystalline solids play an important role in determining the mechanical and thermal properties of materials.The phonon dispersion relation,as well as the vibrational density of state... The phonon dispersion relations of crystalline solids play an important role in determining the mechanical and thermal properties of materials.The phonon dispersion relation,as well as the vibrational density of states,is also often used as an indicator of variation of lattice thermal conductivity with the external stress,defects,etc.In this study,a simple and fast tool is proposed to acquire the phonon dispersion relation of crystalline solids based on the LAMMPS package.The theoretical details for the calculation of the phonon dispersion relation are derived mathematically and the computational flow chart is present.The tool is first used to calculate the phonon dispersion relation of graphene with two atoms in the unit cell.Then,the phonon dispersions corresponding to several potentials or force fields,which are commonly used in the LAMMPS package to modeling the graphene,are obtained to compare with that from the DFT calculation.They are further extended to evaluate the accuracy of the used potentials before the molecular dynamics simulation.The tool is also used to calculate the phonon dispersion relation of superlattice structures that contains more than one hundred of atoms in the unit cell,which predicts the phonon band gaps along the cross-plane direction.Since the phonon dispersion relation plays an important role in the physical properties of condensed matter,the proposed tool for the calculation of the phonon dispersion relation is of great significance for predicting and explaining the mechanical and thermal properties of crystalline solids. 展开更多
关键词 phonon dispersion relation molecular dynamics force constant potential function
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A Simple Approach to Compute Interatomic Force Constant for Mono and Diatomic Semiconductors
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作者 Mohammed Joghlaf Yahya Ababou Salaheddine Sayouri 《Journal of Applied Mathematics and Physics》 2021年第1期11-20,共10页
In this paper, a mathematical relation was found between interatomic Hooke’s force constant and both the bulk modulus and interatomic distance in solid crystals, considering that the forces which have effect on an at... In this paper, a mathematical relation was found between interatomic Hooke’s force constant and both the bulk modulus and interatomic distance in solid crystals, considering that the forces which have effect on an atom are only those resulted from the neighboring atoms, and the forces are subject to Hooke’s law as the deflections of atoms from their equilibrium positions are very small. This work has been applied on some solid semiconducting crystals of diatomic primitive cell, including crystals of mono-atomic primitive cell automatically, by using linear statistical fitting with computer programming and, then, using mathematical analysis, proceeding from the vibrational dispersion relation of solid linear lattice, these two methods have been used in the process in order to support each other and for the result to be satisfying and reasonable. This is a contribution to the process of using computer programming in physics to facilitate mathematical analyses and obtain the required relations and functions by designing and developing appropriate computer programs in line with the macro and micro natures of materials. The importance of this is in enhancing our understanding of the interatomic actions in cells and of the crystal structure of materials in general and semiconductors in particular, as it is a step of the initial steps to facilitate the process of calculating energies and extracting mathematical relations between correlation energy and temperature as well as between sub-fusion and fusion energies with temperature. 展开更多
关键词 Interatomic Force constant Bulk Modulus Vibrational Dispersion relation Linear Fitting Wave Speed
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High Accuracy When Measuring Physical Constants: From the Perspective of the Information-Theoretic Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2020年第5期861-887,共27页
The practical value of high-precision models of the studied physical phenomena and technological processes is a decisive factor in science and technology. Currently, numerous methods and criteria for optimizing models... The practical value of high-precision models of the studied physical phenomena and technological processes is a decisive factor in science and technology. Currently, numerous methods and criteria for optimizing models have been proposed. However, the classification of measurement uncertainties due to the number of variables taken into account and their qualitative choice is still not given sufficient attention. The goal is to develop a new criterion suitable for any groups of experimental data obtained as a result of applying various measurement methods. Using the “information-theoretic method”, we propose two procedures for analyzing experimental results using a quantitative indicator to calculate the relative uncertainty of the measurement model, which, in turn, determines the legitimacy of the declared value of a physical constant. The presented procedure is used to analyze the results of measurements of the Boltzmann constant, Planck constant, Hubble constant and gravitational constant. 展开更多
关键词 Amount of INFORMATION CODATA BOLTZMANN constant GRAVITATIONAL constant HUBBLE constant PLANCK constant International System of Units Mathematical Modeling Measurement relative Uncertainty
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Galactic Route to the Strong Coupling Constant αs(mz) and Its Implication on the Mass Constituents of the Universe
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作者 Hans Hermann Otto 《Journal of Applied Mathematics and Physics》 2022年第12期3572-3585,共14页
Some fundamental physical quantities need an alternative description. We derive the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) from the observed maximum g... Some fundamental physical quantities need an alternative description. We derive the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) from the observed maximum galactic rotation velocity by the simple relation , where is the velocity, at which the difference between galactic rotation velocity and Thomas precession is equal, and α is Sommerfeld’s constant. The result is in excellent agreement with the value of α<sub>s</sub> = 0.1170 ± 0.0019, recently measured and verified via QCE analysis by CERN researchers. One can formulate a reciprocity relation, connecting α<sub>s</sub> with the circle constant: . It is the merit of Preston Guynn to derive the Milky Way maximum value of the galactic rotation velocity β<sub>g</sub>, pointing to its “extremely important role in all physics”. The mass (energy) constituents of the Universe follow a golden mean hierarchy and can simply be related to the maximum of Guynn’s difference velocity respectively to α<sub>s</sub>(m<sub>z</sub>), therewith excellently confirming Bouchet’s WMAP data analysis. We conclude once more that the golden mean concept is the leading one of nature. 展开更多
关键词 Strong Coupling constant Sommerfeld’ constant Gravitational Coupling constant Galactic Velocity Structure-Matter Theory Reciprocity relation Goldem Mean Hierarchy Mass and Energy Constituents of the Universe Superconductivity Matter-Antimatter Asymmetry Unification of Science
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Cosmological Inconstant, Supernovae 1a and Decelerating Expansion
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作者 Russell Bagdoo 《Journal of Modern Physics》 CAS 2023年第5期692-721,共30页
In 1998, two groups of astronomers, one led by Saul Perlmutter and the other by Brian Schmidt, set out to determine the deceleration—and hence the total mass/energy—of the universe by measuring the recession speeds ... In 1998, two groups of astronomers, one led by Saul Perlmutter and the other by Brian Schmidt, set out to determine the deceleration—and hence the total mass/energy—of the universe by measuring the recession speeds of type la supernovae (SN1a), came to an unexpected conclusion: ever since the universe was about 7 billion years old, its expansion rate has not been decelerating. Instead, the expansion rate has been speeding up. To justify this acceleration, they suggested that the universe does have a mysterious dark energy and they have emerged from oblivion the cosmological constant, positive this time, which is consistent with the image of an inflationary universe. To explain the observed dimming of high-redshift SN1a they have bet essentially on their distance revised upwards. We consider that an accelerated expansion leads right to a “dark energy catastrophe” (i.e., the chasm between the current cosmological vacuum density value of 10 GeV/m<sup>3</sup> and the vacuum energy density proposed by quantum field theory of ~10<sup>122</sup> GeV/m<sup>3</sup>). We suppose rather that the universe knows a slowdown expansion under the positive pressure of a dark energy, otherwise called a variable cosmological constant. The dark luminosity of the latter would be that of a “tired light” which has lost energy with distance. As for the low brilliance of SN1a, it is explained by two physical processes: The first relates to their intrinsic brightness—supposedly do not vary over time—which would depend on the chemical conditions which change with the temporal evolution;the second would concern their apparent luminosity. Besides the serious arguments already known, we strongly propose that their luminosity continually fades by interactions with cosmic magnetic fields, like the earthly PVLAS experiment which loses much more laser photons than expected by crossing a magnetic field. It goes in the sense of a “tired light” which has lost energy with distance, and therefore, a decelerated expansion of the universe. Moreover, we propose the “centrist” principle to complete the hypothesis of the cosmological principle of homogeneity and isotropy considered verified. Without denying the Copernican principle, he is opposed to a “spatial” theoretical construction which accelerates the world towards infinity. The centrist principle gives a “temporal” and privileged vision which tends to demonstrate the deceleration of expansion. 展开更多
关键词 Variable Cosmological constant SN1a Dark Energy Catastrophe Theory of relation Deceleration of the Expansion PVLAS Experiment Tired Light Centrist Principle
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Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants
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作者 Xiao-Bin Liang Bo Li Shao-Ming Fei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2024年第9期43-50,共8页
Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical observables.Here,we introduce the concept of optimal observable sets and define the tightest uncer... Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical observables.Here,we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement uncertainties.For any quantum state,we establish optimal sets of three observables for both product and summation forms of uncertainty relations,and analytically derive the corresponding tightest uncertainty constants.We demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation form.Furthermore,the existence of the tightest constants excludes the validity of standard real quantum mechanics,underscoring the essential role of complex numbers in this field.Additionally,our findings resolve the conjecture posed in[Phys.Rev.Lett.118,180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties. 展开更多
关键词 uncertainty relation the tightest uncertainty constants optimal observable sets
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Effect of Gravitational Formula Change on Gravitational Anomalies
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作者 Hans Peter Weber 《Journal of Modern Physics》 2024年第11期1632-1645,共14页
The gravitational constant G is a basic quantity in physics, and, despite its relative imprecision, appears in many formulas, for example, also in the formulas of the Planck units. The “relative inaccuracy” lies in ... The gravitational constant G is a basic quantity in physics, and, despite its relative imprecision, appears in many formulas, for example, also in the formulas of the Planck units. The “relative inaccuracy” lies in the fact that each measurement gives different values, depending on where and with which device the measurement is taken. Ultimately, the mean value was formed and agreed upon as the official value that is used in all calculations. In an effort to explore the reason for the inaccuracy of this quantity, some formulas were configured using G, so that the respective quantity assumed the value = 1. The gravitational constant thus modified was also used in the other Planck equations instead of the conventional G. It turned out that the new values were all equivalent to each other. It was also shown that the new values were all represented by powers of the speed of light. The G was therefore no longer needed. Just like the famous mass/energy equivalence E = m * c2, similar formulas emerged, e.g. mass/momentum = m * c, mass/velocity = m * c2 and so on. This article takes up the idea that emerges in the article by Weber [1], who describes the gravitational constant as a variable (Gvar) and gives some reasons for this. Further reasons are given in the present paper and are computed. For example, the Planck units are set iteratively with the help of the variable Gvar, so that the value of one unit equals 1 in each case. In this article, eleven Planck units are set iteratively using the variable Gvar, so that the value of one unit equals 1 in each case. If all other units are based on the Gvar determined in this way, a matrix of values is created that can be regarded both as conversion factors and as equivalence relationships. It is astonishing, but not surprising that the equivalence relation E = m * c2 is one of these results. All formulas for these equivalence relationships work with the vacuum speed of light c and a new constant K. G, both as a variable and as a constant, no longer appears in these formulae. The new thing about this theory is that the gravitational constant is no longer needed. And if it no longer exists, it can no longer cause any difficulties. The example of the Planck units shows this fact very clearly. This is a radical break with current views. It is also interesting to note that the “magic” number 137 can be calculated from the distances between the values of the matrix. In addition, a similar number can be calculated from the distances between the Planck units. This number is 131 and differs from 137 with 4.14 percent. This difference has certainly often led to confusion, for example, when measuring the Fine Structure Constant. 展开更多
关键词 System of Units Planck constants Gravitational constant Variable Gravitation Equivalence relations Number 137
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Relative dielectric constant from dry rocks
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作者 Xiangyun Wang Huadong Guo +2 位作者 Chao Wang Peirong Chen Yangshen Shi 《Chinese Science Bulletin》 SCIE EI CAS 1999年第24期2286-2293,共8页
Relative dielectric constant is an important physical factor in the theory of microwave remote sensing and electromagnetic transmission. This note reports the results of detecting relative dielectric constant from 197... Relative dielectric constant is an important physical factor in the theory of microwave remote sensing and electromagnetic transmission. This note reports the results of detecting relative dielectric constant from 197 rock samples. The regular pattern of the relative dielectric constant varying with microwave spectrum is revealed. The relative dielectric constants, correlated with the type, density, structure and chemical component of the rock, are discussed. The re- 展开更多
关键词 DRY ROCKS relative dielectric constant microwave REMOTE sensing ELECTROMAGNETIC transmission.
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复杂应力路径下堆石料本构关系研究 被引量:11
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作者 相彪 张宗亮 +1 位作者 迟世春 林皋 《岩土力学》 EI CAS CSCD 北大核心 2010年第6期1716-1722,1728,共8页
已有研究表明,土石坝内堆石料在坝体填筑过程的应力路径可近似为等应力比的路径(q/p=常数),水库蓄水时应力路径将发生转折,呈复杂的应力路径形态(dq/dp=常数)。在大型三轴仪上进行了两种应力路径的排水试验,即等应力比路径下的偏压试验... 已有研究表明,土石坝内堆石料在坝体填筑过程的应力路径可近似为等应力比的路径(q/p=常数),水库蓄水时应力路径将发生转折,呈复杂的应力路径形态(dq/dp=常数)。在大型三轴仪上进行了两种应力路径的排水试验,即等应力比路径下的偏压试验和复杂应力路径下的剪切试验。根据试验结果提出了一个堆石料应力路径增量非线性弹性模型,模型采用三模量形式除可以描述堆石料等应力比路径的应力-应变特征外,通过转折后的路径特征构造合适的柔度矩阵,能够表达转折应力路径下的本构关系。对试验曲线进行拟合表明,应力路径模型能够较好地反映堆石料在复杂应力路径下的应力与变形特性。 展开更多
关键词 等应力比 复杂应力路径 模量 本构关系
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交流励磁变速恒频双馈型异步发电机的稳态功率关系 被引量:52
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作者 刘其辉 贺益康 张建华 《电工技术学报》 EI CSCD 北大核心 2006年第2期39-44,62,共7页
在交流励磁变速恒频发电应用中,双馈型异步发电机(DFIG)的控制对象是定子有功、无功功率,控制变量是转子电压、电流。采用DFIG等效电路,推导基于DFIG控制对象的转子电压、电流计算方法,将转子电压、电流分解为励磁分量、有功分量及无功... 在交流励磁变速恒频发电应用中,双馈型异步发电机(DFIG)的控制对象是定子有功、无功功率,控制变量是转子电压、电流。采用DFIG等效电路,推导基于DFIG控制对象的转子电压、电流计算方法,将转子电压、电流分解为励磁分量、有功分量及无功分量,揭示了DFIG控制对象与控制变量之间的内在联系;研究定、转子的有功、无功功率关系,重点对不同运行条件下DFIG无功功率特性进行探讨,分析DFIG转子无功功率和定子无功功率以及转差之间的关系。 展开更多
关键词 双馈型异步发电机 交流励磁 变速恒频 稳态 功率关系
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