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The assessment of time dependent flow of Williamson fluid with radiative blood flow against a wedge
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作者 K.Subbarayudu S.Suneetha P.Bala Anki Reddy 《Propulsion and Power Research》 SCIE 2020年第1期87-99,共13页
The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic Williamson fluid model.Assuming the flow is unsteady and blood is treated as Williamson fluid over a we... The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic Williamson fluid model.Assuming the flow is unsteady and blood is treated as Williamson fluid over a wedge with radiation.The governing equations are transformed into ordinary differential equations by using similarity variables.The analytical solutions of the transformed governing equations are obtained by using the RK 4th order method along with shooting technique solver.The effects of various physical parameters such as Hartmann number,local Weissenberg number,radiation parameter,unsteadiness parameter,Prandtl number,Lewis number,Brownian diffusion,thermophoresis,wedge angle parameter,moving wedge parameter,on velocity,temperature,concentration,skin friction,heat transfer rate and mass transfer rate have been discussed in detail.The velocity and temperature profile deprives for larger We and an opposite trend is observed for concentration.The radiation parameter is propositional to temperature and a counter behaviour is observed for Pr. 展开更多
关键词 The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic WILLIAMSON fluid model. Assuming the flow IS unsteady and blood IS treated as WILLIAMSON fluid over a WEDGE with radiation. The governing EQUATIONS are transformed into ordinary differential EQUATIONS by using similarity variables. The analytical solutions of the transformed governing EQUATIONS are obtained by using the RK 4th order method along with shooting technique solver. The effects of various physical parameters such as Hartmann NUMBER local Weissenberg NUMBER radiation PARAMETER unsteadiness PARAMETER Prandtl NUMBER Lewis NUMBER Brownian diffusion thermophoresis WEDGE angle PARAMETER moving WEDGE PARAMETER on velocity temperature concentration skin friction heat transfer rate and mass transfer rate have been discussed in detail. The velocity and temperature profile deprives for larger We and an opposite trend IS observed for concentration. The radiation PARAMETER IS propositional to temperature and a counter behaviour IS observed for Pr.
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Theory of Electromagnetism and Gravity —Modeling Earth as a Rotating Solenoid Coil
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作者 Greg Poole 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期663-692,共30页
Presented in this manuscript are conventional electrical engineering tools to model the earth as a rotating electrical machine. Calculations using known parameters of the earth and measured field data has resulted in ... Presented in this manuscript are conventional electrical engineering tools to model the earth as a rotating electrical machine. Calculations using known parameters of the earth and measured field data has resulted in new understanding of the earth’s electrical system and gyroscopic rotation. The material makeup of the inner earth is better understood based on derived permeability and permittivity constants. The planet has been modeled as simple coils and then as a parallel impedance circuit which has led to fundamental insight into planetary speed control and RLC combination for Schumann Resonance of 7.83 Hz. Torque and Voltage Constants and the inverse Speed Constant are calculated using three methods and all compare favorably with Newton’s Gravitational Constant. A helical resonator is referenced and Schumann’s Resonant ideal frequency is calculated and compared with others idealism. A new theory of gravity based on particle velocity selector at the poles is postulated. Two equations are presented as the needed links between Faraday’s electromagnetism and Newtonian physics. Acceleration and Deceleration of earth is explained as a centripetal governor. A new equation for planetary attraction and the attraction of atomic matter is theorized. Rotation of the earth’s electrical coil is explained in terms of the Richardson effect. Electric power transfer from the sun to the planets is proposed via Flux Transfer Events. The impact of this evolving science of electromagnetic modeling of planets will be magnified as the theory is proven, and found to be useful for future generations of engineers and scientists who seek to discover our world and other planets. 展开更多
关键词 Ampere Biot-Savart CENTRIPETAL Acceleration CENTRIPETAL GOVERNOR Dynamo EARTH Einstein-de Haas Effect Electric Field Electromagnetism Flux Transfer Events GOVERNOR Control GRAVITY Gravitational CONSTANT Helical Resonator Lenz Law Lorentz Lightning Magnetic Field Motor CONSTANT Parallel Impedance Planet SPEED Control Schumann Resonance Richardson Effect Solenoid SPEED CONSTANT Solar Power System Torque CONSTANT velocity Selector Voltage CONSTANT
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The Unified Field
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 2024年第7期1010-1035,共26页
This is a Unified Field description based on the holographic Time Dilation Cosmology, TDC, model, which is an eternal continuum evolving forward in the forward direction of time, at the speed of light, c, at an invari... This is a Unified Field description based on the holographic Time Dilation Cosmology, TDC, model, which is an eternal continuum evolving forward in the forward direction of time, at the speed of light, c, at an invariant 1 s/s rate of time. This is the Fundamental Direction of Evolution, FDE. There is also an evolution down time dilation gradients, the Gravitational Direction of Evolution, GDE. These evolutions are gravity, which is the evolutionary force in time. Gravitational velocities are compensation for the difference in the rate of time, dRt, in a dilation field, and the dRtis equal to the compensatory velocity’s percentage of c, and is a measure of the force in time inducing the velocity. In applied force induced velocities, the dRt is a measure of the resistance in time to the induced velocity, which might be called “anti-gravity” or “negative gravity”. The two effects keep the continuum uniformly evolving forward at c. It is demonstrated that gravity is already a part of the electromagnetic field equations in way of the dRt element contained in the TDC velocity formula. Einstein’s energy formula is defined as a velocity formula and a modified version is used for charged elementary particle solutions. A time dilation-based derivation of the Lorentz force ties gravity directly to the electromagnetic field proving the unified field of gravity and the EMF. It is noted how we could possibly create gravity drives. This is followed by a discussion of black holes, proving supermassive objects, like massive black hole singularities, are impossible, and that black holes are massless Magnetospheric Eternally Collapsing Objects (MECOs) that are vortices in spacetime. . 展开更多
关键词 Unified Field GRAVITY Anti-Gravity Astrophysics Einstein General Relativity Special Relativity Galactic Rotation Velocities Time Dilation SPACETIME Space Time Spacetime Continuum Quantum Continuum MECO Black Hole Event Horizon Timelike Spacelike Lightlike
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Determination of Muzzle Velocity Deviation of Propellant Lot by Thermal Physical and Chemical Performances of Propellant
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作者 Liu Yixin Wang Guiyu 《工程科学(英文版)》 2005年第4期16-19,共4页
In this paper the method is put forward that the muzzle velocity deviation of charge lot is determined by thermal performance or component and content of propellant. Live firing or other experiments can be left out by... In this paper the method is put forward that the muzzle velocity deviation of charge lot is determined by thermal performance or component and content of propellant. Live firing or other experiments can be left out by using this method and its accuracy is rather high. 展开更多
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Trans-Thoracic Echocardiographic Aortic Blood Flow Peak Velocity Variation, Distance Minute, Aortic Velocity Time Integral and Postoperative Outcome in Pediatric Surgical Patients—An Observational Pilot Study Protocol 被引量:1
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作者 Claudine Kumba 《Open Journal of Internal Medicine》 2020年第1期90-95,共6页
Background: A Randomized Controlled Trial (RCT) has been elaborated where goal directed fluid and hemodynamic therapy (GDFHT) will be realized with trans-thoracic echocardiographic aortic blood flow peak velocity vari... Background: A Randomized Controlled Trial (RCT) has been elaborated where goal directed fluid and hemodynamic therapy (GDFHT) will be realized with trans-thoracic echocardiographic aortic blood flow peak velocity variation (ΔVpeak) and distance minute (DM) to guide fluid therapy and hemodynamics in high risk pediatric surgical patients. This RCT will clarify the impact of GDFHT with ΔVpeak and DM on postoperative outcome in terms of morbidity, length of stay in the intensive care unit (LOSICU), length of mechanical ventilation (LMV) and length of hospital stay (LOS) in children. To determine values of ΔVpeak, DM and VTI predictive of these postoperative outcomes, an observational pilot study will be realized. This pilot study is described here. The primary objective of this study is to determine values of ΔVpeak, DM and ITV predictive of postoperative outcome in children in terms of morbidity. The secondary objectives are to determine values of ΔVpeak, DM and ITV predictive of LOSICU, LMV, LOS, intraoperative, postoperative fluid administration and vasoactive-inotropic therapy. Methods: 500 - 1000 children aged less than 18 years will be included prospectively. Statistic analysis will be realized with XLSTAT 2019.4.2 software or plus. Results and Conclusions: This trial protocol will determine values of ΔVpeak, DM and ITV with echocardiography predictive of postoperative outcome in children. 展开更多
关键词 Children AORTIC Blood Flow Peak velocity Variation AORTIC velocity Time INTEGRAL Distance MINUTE Postoperative Outcome Pilot Study Protocol Trans-Thoracic Echocardiography
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Problems and Solutions of Velocity Modeling in Natural Gas Exploration
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作者 Aiqun Liu Caiwei Fan +3 位作者 Yong Deng Peiyuan Zhu Qianwei Hu Peng Song 《Open Journal of Marine Science》 2017年第1期51-61,共11页
Recently, velocity prediction and modeling have been focus of the geophysical exploration in the high temperature and high pressure of the south China sea area, especially for new offshore exploratory areas. The error... Recently, velocity prediction and modeling have been focus of the geophysical exploration in the high temperature and high pressure of the south China sea area, especially for new offshore exploratory areas. The error is large with great difficulty owing to fewer exploratory wells and misunderstanding. Firstly, on the basis of three typical velocity prediction and modeling examples in Ying-Qiong basin, it’s easy to put forward the corresponding not common but urgent problem in each instance, then combined with the velocity problem and misunderstanding to expand method discussion and solution, which include geological model to guide the velocity interpretation and analysis, the establishment of forward velocity of the auxiliary model explaining and constructing high precision velocity model. This research basically solves existing velocity problems in gas exploration of south China sea in recent years, and proposes corresponding solution and application, which is of great significance to the further exploration and productive practice. 展开更多
关键词 Ying-Qiong Basin Natural Gas Exploration velocity MODELING velocity Prediction velocity Analysis velocity Volume The GEOLOGICAL MODEL INCLINATION Correction High Precision velocity MODEL Forward MODELING
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The hydrothermal wave of large-Prandtl-number fluid in a shallow cavity 被引量:3
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作者 TANG ZeMei & HU WenRui National Microgravity Laboratory,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100080,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期787-796,共10页
The hydrothermal wave was investigated numerically for large-Prandtl-number fluid (Pr = 105.6) in a shallow cavity with different heated sidewalls. The traveling wave appears and propagates in the direction opposite t... The hydrothermal wave was investigated numerically for large-Prandtl-number fluid (Pr = 105.6) in a shallow cavity with different heated sidewalls. The traveling wave appears and propagates in the direction opposite to the surface flow (upstream) in the case of zero gravity when the applied temperature difference grows and over the critical value. The phase relationships of the disturbed velocity,temperature and pressure demonstrate that the traveling wave is driven by the disturbed tem-perature,which is named hydrothermal wave. The hydrothermal wave is so weak that the oscillatory flow field and temperature distribution can hardly be observed in the liquid layer. The exciting mechanism of hydrothermal wave is analyzed and discussed in the present paper. 展开更多
关键词 HYDROTHERMAL wave numerical simulation microgravity The HYDROTHERMAL WAVE was investigated numerically for large-Prandtl-number FLUID (Pr = 105.6) in a shallow cavity with different heated sidewalls. The TRAVELING WAVE appears and propagates in the direction opposite to the surface flow (upstream) in the case of zero gravity when the applied TEMPERATURE difference grows and over the critical value. The phase relationships of the disturbed velocity TEMPERATURE and pressure demonstrate that the TRAVELING WAVE IS driven by the disturbed temperature which IS named HYDROTHERMAL wave. The HYDROTHERMAL WAVE IS so weak that the oscillatory flow field and TEMPERATURE distribution can hardly be observed in the liquid layer. The exciting mechanism of HYDROTHERMAL WAVE IS analyzed and discussed in the present paper.
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Threshold friction velocity influenced by soil particle size within the Columbia Plateau, northwestern United States
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作者 MENG Ruibing MENG Zhongju +3 位作者 Brenton SHARRATT ZHANG Jianguo CAI Jiale CHEN Xiaoyan 《Journal of Arid Land》 SCIE CSCD 2024年第8期1147-1162,共16页
Wind erosion is a geomorphic process in arid and semi-arid areas and has substantial implications for regional climate and desertification.In the Columbia Plateau of northwestern United States,the emissions from fine ... Wind erosion is a geomorphic process in arid and semi-arid areas and has substantial implications for regional climate and desertification.In the Columbia Plateau of northwestern United States,the emissions from fine particles of loessial soils often contribute to the exceedance of inhalable particulate matter(PM)with an aerodynamic diameter of 10μm or less(PM10)according to the air quality standards.However,little is known about the threshold friction velocity(TFV)for particles of different sizes that comprise these soils.In this study,soil samples of two representative soil types(Warden sandy loam and Ritzville silt loam)collected from the Columbia Plateau were sieved to seven particle size fractions,and an experiment was then conducted to determine the relationship between TFV and particle size fraction.The results revealed that soil particle size significantly affected the initiation of soil movement and TFV;TFV ranged 0.304-0.844 and 0.249-0.739 m/s for different particle size fractions of Ritzville silt loam and Warden sandy loam,respectively.PM10 and total suspended particulates(TSP)emissions from a bed of 63-90μm soil particles were markedly higher for Warden sandy loam than for Ritzville silt loam.Together with the lower TFV of Warden sandy loam,dust emissions from fine particles(<100μm in diameter)of Warden sandy loam thus may be a main contributor to dust in the region's atmosphere,since the PM10 emissions from the soil erosion surfaces and its ensuing suspension within the atmosphere constitute an essential process of soil erosion in the Columbia Plateau.Developing and implementing strategic land management practices on sandy loam soils is therefore necessary to control dust emissions in the Columbia Plateau. 展开更多
关键词 particle size threshold friction velocity inhalable particulate matter total suspended particles Warden sandy loam Ritzville silt loam Columbia Plateau
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Determination of Muzzle Velocity Loss by Bore Wear Pattern
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作者 刘怡昕 王桂玉 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第2期98-101,共4页
A method to determine muzzle velocity loss according to the actual measured bore wear pattern is proposed.Therefore,it is unnecessary to conduct live firing and other experiments for determination of muzzle velocity l... A method to determine muzzle velocity loss according to the actual measured bore wear pattern is proposed.Therefore,it is unnecessary to conduct live firing and other experiments for determination of muzzle velocity loss.It has been applied to a national military standard since July 1,2004. 展开更多
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Configuration of propagator method for calculation of electron velocity distribution function in gas under crossed electric and magnetic fields
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作者 Hirotake SUGAWARA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第9期1-18,共18页
This paper presents a self-contained description on the configuration of propagator method(PM)to calculate the electron velocity distribution function(EVDF) of electron swarms in gases under DC electric and magnetic f... This paper presents a self-contained description on the configuration of propagator method(PM)to calculate the electron velocity distribution function(EVDF) of electron swarms in gases under DC electric and magnetic fields crossed at a right angle. Velocity space is divided into cells with respect to three polar coordinates v,θ and f. The number of electrons in each cell is stored in three-dimensional arrays. The changes of electron velocity due to acceleration by the electric and magnetic fields and scattering by gas molecules are treated as intercellular electron transfers on the basis of the Boltzmann equation and are represented using operators called the propagators or Green’s functions. The collision propagator, assuming isotropic scattering, is basically unchanged from conventional PMs performed under electric fields without magnetic fields. On the other hand, the acceleration propagator is customized for rotational acceleration under the action of the Lorentz force. The acceleration propagator specific to the present cell configuration is analytically derived. The mean electron energy and average electron velocity vector in a model gas and SF6 were derived from the EVDF as a demonstration of the PM under the Hall deflection and they were in a fine agreement with those obtained by Monte Carlo simulations. A strategy for fast relaxation is discussed, and extension of the PM for the EVDF under AC electric and DC/AC magnetic fields is outlined as well. 展开更多
关键词 PROPAGATOR method ELECTRON velocity distribution function ELECTRON transport COEFFICIENTS CROSSED electric and magnetic fields MAGNETIZED plasma BOLTZMANN equation
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A froth velocity measurement method based on improved U-Net++semantic segmentation in flotation process
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作者 Yiwei Chen Degang Xu Kun Wan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第8期1816-1827,共12页
During flotation,the features of the froth image are highly correlated with the concentrate grade and the corresponding working conditions.The static features such as color and size of the bubbles and the dynamic feat... During flotation,the features of the froth image are highly correlated with the concentrate grade and the corresponding working conditions.The static features such as color and size of the bubbles and the dynamic features such as velocity have obvious differences between different working conditions.The extraction of these features is typically relied on the outcomes of image segmentation at the froth edge,making the segmentation of froth image the basis for studying its visual information.Meanwhile,the absence of scientifically reliable training data with label and the necessity to manually construct dataset and label make the study difficult in the mineral flotation.To solve this problem,this paper constructs a tungsten concentrate froth image dataset,and proposes a data augmentation network based on Conditional Generative Adversarial Nets(cGAN)and a U-Net++-based edge segmentation network.The performance of this algorithm is also evaluated and contrasted with other algorithms in this paper.On the results of semantic segmentation,a phase-correlationbased velocity extraction method is finally suggested. 展开更多
关键词 froth flotation froth segmentation froth image data augmentation velocity extraction image features
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Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr
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作者 Y.El jariri F.L.Sefyani +5 位作者 A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib M.Sabil 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期253-272,共20页
The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating stars.In this article,we present a study of this phenomenon through th... The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating stars.In this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 yr.We based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(Morocco)between 2015 and 2016.Through this study,we have detected information on atmospheric dynamics that had not previously been detected.Indeed,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as well.For the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko cycle.Furthermore,we found that the Van Hoof effect is also modulated by the Blazhko effect.Thus,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is minimal.We also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper atmosphere.When observed over a long time,we can interpret it as a function of the Blazhko phases. 展开更多
关键词 stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)
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Velocity Form Calculations of Generalized Oscillator Strengths for 3s→ (3p, 4p, 5p, 6p) Dipole Transitions of Atomic Sodium in Debye Plasma
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作者 Louis Gomis Clement Diatta +4 位作者 Moustapha Sadibou Tall Ibrahima Gueye Faye Rama Gomis Yande Diouf Mamadou Coulibaly 《Open Journal of Applied Sciences》 2024年第6期1512-1529,共18页
In this paper, the generalized oscillator strengths (GOSs) of excitations of atomic sodium from ground state to 2p63s0 (3p, 4p, 5p, 6p) states, immersed in Debye plasma, were calculated by using wavefunctions which we... In this paper, the generalized oscillator strengths (GOSs) of excitations of atomic sodium from ground state to 2p63s0 (3p, 4p, 5p, 6p) states, immersed in Debye plasma, were calculated by using wavefunctions which were obtained numerically from the restricted Hartree-Fock (RHF) equation. This RHF equation employs the local density approach for exchange interactions including plasma Debye screening. Theoretical RHF and random phase approximation with exchange (RPAE) velocity calculations have shown that the GOSs for excitations to 3 s0(3 p,4 p,5 p,6 p)depend on the plasma Debye screening effects, as shown by the reduction in the GOS amplitude with decreasing Debye length λD. The agreement between the present RPAE V results for the transitions 3 s→3 s0(3 p,4 p,5 p)and the length calculations of Martínez-Flores was satisfactory. Correlation effects were found quite to be significant in the vicinity of the maxima of the GOS of the 3 s→3 s0(4 p,5 p,6 p)excitations by using the RPAE V approach. We note the poor influence of many electron correlations on the GOS of (3 s→3 p)transition with the same principal quantum number. Finally, we comment that the RPAE V calculations are useful in investigating electron correlation effects on the transition GOS of atomic sodium planted in Debye plasma. The present velocity results also reveal that the 3 s→3 s0(5p, 6p)transition GOSs tend to be delocalized due to more significant screening effects at Debye lengths λD=20and 30 a.u. for excited subshells 5p and 6p, respectively. We report here novel results of GOS for 3 s→3 s06ptransition obtained from different Debye lengths. 展开更多
关键词 Plasma Screening Effect Correlation Effect Sodium Atomic velocity Form GOS Restricted Hatree-Fock Random Phase Approximation with Exchange
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任意各向异性介质方位旅行时正演 被引量:8
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作者 熊金良 刘洋 侯伯刚 《石油地球物理勘探》 EI CSCD 北大核心 2005年第3期300-304,共5页
在研究任意各向异性介质中的旅行时正演方法时,针对含气裂隙和含水裂隙模型,本文给出了各向异性介质中射线追踪计算方法。计算结果表明:①在垂直裂隙情况下,纵波反射时间随炮检距、方位角变化,含气裂隙纵波反射时间的方位差异和炮检距... 在研究任意各向异性介质中的旅行时正演方法时,针对含气裂隙和含水裂隙模型,本文给出了各向异性介质中射线追踪计算方法。计算结果表明:①在垂直裂隙情况下,纵波反射时间随炮检距、方位角变化,含气裂隙纵波反射时间的方位差异和炮检距差异更为明显;②在相同炮检距时,随着方位角变化反射波旅行时间呈近似椭圆规律变化,含气裂隙介质反射时间的方位差异比含水裂隙差异明显;③在不同裂隙面倾角情况下,反射波旅行时间的方位差异在裂隙面垂直时最为明显,然后随裂隙倾角的减小而减小,当裂隙面水平时变成方位各向同性介质;④在不同方位的测线中,以垂直裂隙走向测线的.纵波反射时间与平行于裂隙走向测线的纵波反射时间差异最大。 展开更多
关键词 线 线
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任意空间取向TI介质中体波速度特征分析 被引量:3
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作者 郝重涛 姚陈 王迅 《地震地质》 EI CSCD 北大核心 2005年第2期252-259,共8页
基于任意空间取向TI介质(简称ATI)中体波速度和偏振解析解,通过模型数值计算给出ATI介质中体波群速度和相速度的变化特征,说明TI空间取向与测线方位对速度的影响。研究表明,体波群速度图案和相速度图案相对TI对称轴固定,随TI对称轴倾角... 基于任意空间取向TI介质(简称ATI)中体波速度和偏振解析解,通过模型数值计算给出ATI介质中体波群速度和相速度的变化特征,说明TI空间取向与测线方位对速度的影响。研究表明,体波群速度图案和相速度图案相对TI对称轴固定,随TI对称轴倾角及其相对测线方位角的变化呈现出一定的对称性和重复性;可以针对ATI地区的地质情况,给出体波群速度和相速度变化图案,为进一步的理论研究提供便捷。此结果也可以直接用于VSP(垂直地震剖面)和井间地震资料的分析研究。 展开更多
关键词 TI ATI VSP 线
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On the Reversal Effects of the Velocity Quotient on the Directions of Changes of Finishing Results of Conventional and Flexible Grinding
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作者 Zdzislaw Pluta Tadeusz Hryniewicz 《Journal of Quantum Information Science》 2011年第3期149-160,共12页
The paper presents the problem of right direction of changes of the velocity quotient in view of getting advantageous smoothing results of material finishing using a compact elastic wheel. In fact the problem has been... The paper presents the problem of right direction of changes of the velocity quotient in view of getting advantageous smoothing results of material finishing using a compact elastic wheel. In fact the problem has been considered reversely in comparison with the change direction of the velocity quotient on the grounds of knowledge on grinding using ceramic wheels. The specifics of performance of the elastic wheels are considered. The investigation was carried out on the effect of their peripheral velocity on the directions of smoothing. The problem is considered by presenting it on the background of determined results of grinding using a ceramic wheel. The dependence of a determined roughness measure of the smoothed surface on the velocity quotient is delivered. The forms of a function approximating experimental dependences of the subject roughness measure on the mentioned quotient have been derived. Furthermore, the results coming out of the performed experimental studies have been presented. 展开更多
关键词 Elastic GRINDING Wheel Peripheral velocity velocity QUOTIENT Measure of Surface Roughness POTENTIAL Field POTENTIAL Band Nominal QUOTIENT CONSTANT Real QUOTIENT CONSTANT
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外界风对小城镇多层建筑火灾流场的影响 被引量:7
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作者 李耀庄 蒋春艳 李博 《中国安全科学学报》 CAS CSCD 2005年第4期48-51,共4页
随着市场经济的不断发展,城市化的进程加快,农村人口向城市流动,使小城镇建设规模不断扩大,因而火灾等各种灾害对小城镇居民的生命和财产所造成的损失也越来越大。火灾时,外界风向、风速对火灾流场可能产生很大的影响。笔者根据小城镇... 随着市场经济的不断发展,城市化的进程加快,农村人口向城市流动,使小城镇建设规模不断扩大,因而火灾等各种灾害对小城镇居民的生命和财产所造成的损失也越来越大。火灾时,外界风向、风速对火灾流场可能产生很大的影响。笔者根据小城镇一般民宅和建筑物的高度特点建立相应的几何模型和物理模型,利用Phoenics软件,从理论上研究了小城镇一幢楼房不同位置的房间发生火灾时,外界吹来不同风速的正向或侧向风,对房间内外稳态温度场与流场的影响。特别研究了房间内热气流流出窗外向上运动的浮力和外界风力相互作用发生的现象及其对房间内流动的影响。同时,还对不同外界风速情况下。 展开更多
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Optimal Guidance Law to Maximize Terminal Velocity for Missiles with Impact Angle Constraint 被引量:1
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作者 Chao Ming Ruisheng Sun Chuanjie Sun 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第2期72-78,共7页
In this paper,an optimal guidance law for missiles with impact angle and miss distance constraints is proposed to achieve the maximal terminal velocity. The normal acceleration command that includes the timevarying co... In this paper,an optimal guidance law for missiles with impact angle and miss distance constraints is proposed to achieve the maximal terminal velocity. The normal acceleration command that includes the timevarying coefficients is introduced to satisfy the desired impact angle as well as zero miss distance according to the geometric relation and relative motion parameters between missile and target. The problem is formulated as an optimal control problem by defining the angle of velocity error and flight-path angle as state variables and maximizing a performance index of the terminal velocity. The analytical form of the proposed guidance law is obtained as the solution of the optimal control problem combining optimal control theory and numerical value computation method. Nonlinear simulations of various situations demonstrate the performance and feasibility of the proposed optimal guidance law. 展开更多
关键词 optimal guidance LAW MAXIMUM TERMINAL velocity missiles impact angle and MISS DISTANCE constraints analytical for^m
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DNS Analysis on the Indirect Relationship between the Local Burning Velocity and the Flame Displacement Speed of Turbulent Premixed Flames
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作者 Kazuya Tsuboi Eiji Tomita 《Open Journal of Fluid Dynamics》 2014年第3期288-297,共10页
The local burning velocity and the flame displacement speed are the dominant properties in the mechanism of turbulent premixed combustion. The flame displacement speed and the local burning velocity have been investig... The local burning velocity and the flame displacement speed are the dominant properties in the mechanism of turbulent premixed combustion. The flame displacement speed and the local burning velocity have been investigated separately, because the flame displacement speed can be used for the discussion of flame-turbulence interactions and the local burning velocity can be used for the discussion of the inner structure of turbulent premixed flames. In this study, to establish the basis for the discussion on the effects of turbulence on the inner structure of turbulent premixed flames, the indirect relationship between the flame displacement speed and the local burning velocity was investigated by the flame stretch, the flame curvature, and the tangential strain rate using DNS database with different density ratios. It was found that for the local tangential strain rate and the local flame curvature, the local burning velocity and the flame displacement speed had the opposite correlations in each density ratio case. Therefore, it is considered that the local burning velocity and the flame displacement speed have a negative correlation. 展开更多
关键词 LOCAL Burning velocity FLAME DISPLACEMENT Speed FLAME STRETCH RATE Tangential Strain RATE FLAME Curvature Turbulent PREMIXED FLAME Direct Numerical Simulation
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Measurement Method of Graviton Velocity and Thought on Correcting Lorentz Transformation——The Superluminal Neutrino’s Influence on Special Relativity and Other Physical Theories
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作者 Ping’an Luo 《Journal of Modern Physics》 2012年第4期297-303,共7页
After discovery of the superluminal particle and consideration on development of contemporary physical theory research, also on the existing errors and omissions, the principle of constant light speed is found not a n... After discovery of the superluminal particle and consideration on development of contemporary physical theory research, also on the existing errors and omissions, the principle of constant light speed is found not a necessary condition in derivation of Lorentz Transformation;instead, this thesis proposes the velocity of graviton may feature superluminal, constant velocity in different directions, and independence of inertial reference frame speeds. This is an optional thought of correction. According serial hypothesis, an equation of graviton’s motion trace, i.e., the central curve of nebula density, is established for spiral galaxy. Thus we gain the method to measure velocity of graviton. If to totally avoid problem of limit speed, we have to search for independent of inertia frames, and relevant to space-time properties. Regarding current difficulties of singular points in the Theory of Limited Universe, this thesis points out that the document [1] is the best solution to these difficulties. 展开更多
关键词 Special RELATIVITY LORENTZ Transformation SUPERLUMINAL Graviton Measurement Method of Graviton velocity Singular Point The Theory of Limited Universe
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