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THE FUZZY NUMERICAL VALUE SIMULATION OF NANOMETER ELECTRO-THERMAL IN HOT-WORKING
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作者 P. He 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2005年第6期731-735,共5页
The fuzzy numerical value analysis method is adopted for the first time, which solves the problem of nanometer electro-thermal in filming process, The key technique is embodied by controlling the time distribution, te... The fuzzy numerical value analysis method is adopted for the first time, which solves the problem of nanometer electro-thermal in filming process, The key technique is embodied by controlling the time distribution, temperature and press in the filming process. The concrete technique of filming is showed by establishing the fuzzy mumbership function of above three indexes, which improves the precision of the materials of nanometer electro-thermal in hot-working. At the same time, the principles of the fuzzy relationship mapping inversion (FRMI) is put forward, Therefore, the standardization and continuity can be met. 展开更多
关键词 fuzzy control FRMI (fuzzy relationship mapping inversion) nanometer electro-thermal fuzzy numerical value simulation
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SEVERAL NEW TYPES OF FINITE-DIFFERENCE SCHEMES FOR SHALLOW-WATER EQUATION WITH INITIAL-BOUNDARY VALUE AND THEIR NUMERICAL EXPERIMENT
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作者 吕秋强 周钢 刘应中 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第3期271-281,共11页
This paper proposed several new types of finite-difference methods for the shallow water equation in absolute coordinate system and put forward an effective two-step predictor-corrector method, a compact and iterative... This paper proposed several new types of finite-difference methods for the shallow water equation in absolute coordinate system and put forward an effective two-step predictor-corrector method, a compact and iterative algorithm for five diagonal matrix. Then the iterative method was used for a multi-grid procedure for shallow water equation. A t last, an initial-boundary value problem was considered, and the numerical results show that the linear sinusoidal wave would successively evolve into conoidal wave. 展开更多
关键词 In SEVERAL NEW TYPES OF FINITE-DIFFERENCE SCHEMES FOR SHALLOW-WATER EQUATION WITH INITIAL-BOUNDARY value AND THEIR numericAL EXPERIMENT
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RESEARCH OF REGULARITY OF THROWING MOVEMENT FOR SOLID PARTICLE ON THE SHAKER'S SCREEN 被引量:2
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作者 姚恒申 杜坚 张明洪 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第6期655-659,共5页
By means of Delta-function & unit step function to express the force of solid particle on plane inertial shaker's screen, an mathematical model of the differential equation type was set up and solved. Accordin... By means of Delta-function & unit step function to express the force of solid particle on plane inertial shaker's screen, an mathematical model of the differential equation type was set up and solved. According to analysis of the solution, the relation is given between the throw period & displacement with the parameters of shaker design & solid particle. The method of numerical value calculation & analysis for the relation is given too. 展开更多
关键词 PETROLEUM drilling fluid SHAKER DELTA-FUNCTION unit step function differential equation numerical value calculation
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An Alternative to Dark Matter? Part 1: The Early Universe (<i>t<sub>p</sub></i>to 10<sup>-9</sup>s), Energy Creation the Alphaton, Baryogenesis 被引量:2
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作者 Jean Perron 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期784-807,共24页
A cosmological model was developed using the equation of state of photon gas, as well as cosmic time. The primary objective of this model is to see if determining the observed rotation speed of galactic matter is poss... A cosmological model was developed using the equation of state of photon gas, as well as cosmic time. The primary objective of this model is to see if determining the observed rotation speed of galactic matter is possible, without using dark matter (halo) as a parameter. To do so, a numerical application of the evolution of variables in accordance with cosmic time and a new state equation was developed to determine precise, realistic values for a number of cosmological parameters, such as the energy of the universe <i>U</i>, cosmological constant Λ, the curvature of space <i>k</i>, energy density <i>ρ</i><sub>Λe</sub>, age of the universe <i>t</i><sub>Ω</sub> etc. The development of the state equation highlights the importance of not neglecting any of the differential terms given the very large amounts in play that can counterbalance the infinitesimals. Some assumptions were put forth in order to solve these equations. The current version of the model partially explains several of the observed phenomena that raise questions. Numerical application of the model has yielded the following results, among others: Initially, during the Planck era, at the very beginning of Planck time, <i>t<sub>p</sub></i>, the universe contained a single photon at Planck temperature <i>T<sub>P</sub></i>, almost Planck energy <i>E<sub>P</sub></i> in the Planck volume. During the photon inflation phase (before characteristic time ~10<sup>-9</sup> [s]), the number of original photons (alphatons) increased at each unit of Planck time <i>t<sub>p</sub></i> and geometrical progression~<i>n</i><sup>3</sup>, where n is the quotient of cosmic time over Planck time <i>t</i>/<i>t<sub>p</sub></i>. Then, the primordial number of photons reached a maximum of <i>N</i>~10<sup>89</sup>, where it remained constant. These primordial photons (alphatons) are still present today and represent the essential of the energy contained in the universe via the cosmological constant expressed in the form of energy <i>E</i><sub>Λ</sub>. Such geometric growth in the number of photons can bring a solution to the horizon problem through <i>γγ</i> exchange and a photon energy volume that is in phase with that of the volume energy of the universe. The predicted total mass (p, n, e, and <i>ν</i>), based on the Maxwell-Juttner relativistic statistical distribution, is ~7 × 10<sup>50</sup> [kg]. The predicted cosmic neutrino mass is ≤8.69 × 10<sup>-32</sup> [kg] (≤48.7 [keV·<i>c</i><sup>-2</sup>]) if based on observations of SN1987A. The temperature variation of the cosmic microwave background (CMB), as measured by Planck, can be said to be partially due to energy variations in the universe (Δ<i>U</i>/<i>U</i>) during the primordial baryon synthesis (energy jump from the creation of protons and neutrons). 展开更多
关键词 Cosmological Parameters numerical values Cosmology Early Universe
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ANALYSIS OF MULTICONDUCTOR TRANSMISSION LINES USING THE MACCORMACK METHOD
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作者 Dou Lei Wang Zhiquan 《Journal of Electronics(China)》 2006年第5期753-757,共5页
The MacCormack method is applied to the analysis of multiconductor transmission lines by intro- ducing a new technique that does not require decoupling. This method can be used to analyze a wide range of problems and ... The MacCormack method is applied to the analysis of multiconductor transmission lines by intro- ducing a new technique that does not require decoupling. This method can be used to analyze a wide range of problems and does not have to consider the matrix forms of distributed parameters. We have developed soft- ware named MacCormack Transmission Line Analyzer based on the proposed method. Numerical examples are presented to demonstrate the accuracy and efficiency of the method and illustrate its application to analyz- ing multiconductor transmission lines. 展开更多
关键词 Multiconductor transmission lines MacCormack method numerical value simulation
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An Alternative to the Dark Matter? Part 2: A Close Universe (10<sup>-9</sup>s to 3 Gy), Galaxies and Structures Formation
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作者 Jean Perron 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期808-843,共36页
A cosmological model was developed using the equation of state of photon gas, as well as cosmic time. The primary objective of this model is to see if determining the observed rotation speed of galactic matter is poss... A cosmological model was developed using the equation of state of photon gas, as well as cosmic time. The primary objective of this model is to see if determining the observed rotation speed of galactic matter is possible, without using dark matter (halo) as a parameter. To do so, a numerical application of the evolution of variables in accordance with cosmic time and a new state equation was developed to determine precise, realistic values for a number of cosmological parameters, such as the energy of the universe <i>U</i>, cosmological constant Λ, the curvature of space <i>k</i>, energy density <i>ρ</i><sub>Λe</sub> (part 1). The age of the universe in cosmic time that is in line with positive energy conservation (in terms of conventional thermodynamics) and the creation of proton, neutron, electron, and neutrino masses, is ~76 [Gy] (observed <img src="Edit_6d0b63d7-3b06-4a39-97c8-a0004319d14d.png" width="15" height="15" alt="" /> ~ 70 [km · s<sup>-1</sup> · Mpc<sup>-1</sup>]). In this model, what is usually referred to as dark energy actually corresponds to the energy of the universe that has not been converted to mass, and which acts on the mass created by the energy-mass equivalence principle and the cosmological gravity field, F<sub>Λ</sub>, associated with the cosmological constant, which is high during the primordial formation of the galaxies (<1 [Gy]). A look at the Casimir effect makes it possible to estimate a minimum Casimir pressure <i>P<sub>c</sub></i><sup>0</sup> and thus determine our possible relative position in the universe at cosmic time 0.1813 (<i>t</i><sub>0</sub>/<i>t</i><sub>Ω</sub> = 13.8[Gy]/76.1[Gy]). Therefore, from the observed age of 13.8 [Gy], we can derive a possible cosmic age of ~76.1 [Gy]. That energy of the universe, when taken into consideration during the formation of the first galaxies (<1 [Gy]), provides a relatively adequate explanation of the non-Keplerian rotation of galactic masses. 展开更多
关键词 Cosmological Parameters numerical values Cosmology Early Universe Galaxies Kinematic and Dynamic
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Numeric modelling and risk assessment of pollutions in the Chinese Bohai Sea 被引量:1
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作者 LIU YongZhi SHEN YouLi +1 位作者 LV XianQing LIU Qiang 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第8期1546-1557,共12页
To simulate the dynamic process of total nitrogen(TN) in seas, numerical modelling combined with the adjoint method is implemented in this study. Because nonpoint source terms(ST) and initial values(IV) of TN are esse... To simulate the dynamic process of total nitrogen(TN) in seas, numerical modelling combined with the adjoint method is implemented in this study. Because nonpoint source terms(ST) and initial values(IV) of TN are essential but difficult to determine, the adjoint method was applied to a numerical model, and the ST and IV terms of TN were inverted via routine monitoring data in the Bohai Sea. In twin experiments, the adjoint method was capable of inverting the prescribed spatio-temporally distributed ST and the spatial distributed IV. In practical experiments, the results demonstrated that the simulation precision with ST inversion was higher than that with IV inversion and was accurate with joint initial values and source term(IST) inversion. This result indicates that nonpoint source TN is essential for the simulation of TN concentration. Furthermore, the simulated results indicate that the pollution in three bays of the Bohai Sea is rather severe. The model in this study is not specific to the Bohai Sea and can be generalized to other areas, such as the Beibu Gulf. These findings may assist in the development of cost-effective controls for accidental or planned industrial pollutant releases into coastal waters. 展开更多
关键词 Risk assessment Adjoint method Initial value numeric modelling Bohai Sea of China
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