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A Mode of Electromagnetic Wave Propagation Based on the Inter-induction of Scalar Electric Field and Vortex Magnetic Field
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作者 Jiang Jianzhong 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第4期134-143,共10页
Drawing upon the electromagnetic conversion formulas in a continuous conductive medium,an extensive examination for total current law and Faraday’s law of electromagnetic induction(Faraday’s law)is undertaken to exp... Drawing upon the electromagnetic conversion formulas in a continuous conductive medium,an extensive examination for total current law and Faraday’s law of electromagnetic induction(Faraday’s law)is undertaken to expound on the laws of electromagnetic induction and conversion.The longitudinal wave term of Faraday’s law is reinstated to render it suitable for theoretical derivation of the LEM(Longitudinal Electromagnetic Wave)equation.Subsequently,we formulate the wave and energy equations for electric P-wave based on reevaluated total current law and modified Faraday’s law;meanwhile proposing a propagation mode that reveals its mechanisms absorbing free energy for LEM waves in a conductor predicated on interaction between scalar electric field and vortex magnetic field.Furthermore,through theoretical derivations based on LEM waves,insights into concealed relationships between electric P-wave and electromagnetism scalar potential are disclosed alongside the constraint equation between the wave velocities of LEM wave and TEM(Transverse Electromagnetic)waves,unveiling the significance of LEM wave. 展开更多
关键词 Quantum electrodynamics LEM modified Faraday’s law of electromagnetic induction electromagnetic vortex potential zero-point vacuum energy
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基于量子衍生涡流算法和T⁃S模糊推理模型的储层岩性识别
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作者 赵娅 管玉 +1 位作者 李盼池 王伟 《石油地球物理勘探》 EI CSCD 北大核心 2024年第1期23-30,共8页
鉴于梯度下降法易陷入局部极值、普通群智能优化算法易早熟收敛,提出一种基于量子衍生涡流算法(Quantum Vortex Search Algorithm,QVSA)和T⁃S模糊推理模型的岩性识别方法,QVSA具有操作简单、收敛速度快、寻优能力强等优点,有助于T⁃S模... 鉴于梯度下降法易陷入局部极值、普通群智能优化算法易早熟收敛,提出一种基于量子衍生涡流算法(Quantum Vortex Search Algorithm,QVSA)和T⁃S模糊推理模型的岩性识别方法,QVSA具有操作简单、收敛速度快、寻优能力强等优点,有助于T⁃S模糊推理模型获得最优参数配置,从而实现储层岩性的准确识别。首先利用具有全局搜索能力的QVSA优化T⁃S模糊推理模型的各种参数;然后利用主成分分析方法降低获取的地震属性维度;再利用优化的T⁃S模糊推理模型识别储层岩性。实验结果表明,利用反映储层特征的8个地震属性识别储层岩性时,所提方法的识别正确率达到92%,比普通BP网络方法高5.1%,同时查准率、查全率、F1分数等指标也较BP网络方法提升明显。 展开更多
关键词 储层岩性识别 量子衍生涡流算法 T⁃s 模糊推理模型 模糊集 地震属性
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A Darcy-Law Based Model for Heat and Moisture Transfer in a Hill Cave 被引量:1
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作者 Fei Liu Dongliang Zhang +1 位作者 Qifu Zhu Qingyong Su 《Fluid Dynamics & Materials Processing》 EI 2023年第9期2345-2359,共15页
A hill can be regarded as an environmental carrier of heat.Water,rocks and the internal moisture naturally pre-sent in such environment constitute a natural heat accumulator.In the present study,the heat and moisture ... A hill can be regarded as an environmental carrier of heat.Water,rocks and the internal moisture naturally pre-sent in such environment constitute a natural heat accumulator.In the present study,the heat and moisture trans-fer characteristics in a representative hill cave have been simulated via a method relying on the Darcy’s law.The simulations have been conducted for both steady and unsteady conditions to discern the influence of permeability and geometric parameters on the thermal and moisture transfer processes.The reliability of the simulation has been verified through comparison of the numerical results with the annual observation data.As revealed by the numericalfindings,the internal temperature of the hill accumulator is proportional to the permeability,outside surface temperature,overground height,underground constant temperature layer depth,and underground tem-perature of the hill,and it is inversely proportional to the horizontal size of the hill.Moreover,in the considered case,the order of magnitude of the permeability of the hill is contained in the range 10-15–10-13,and displays a certain sensitivity to the rainwater seepage. 展开更多
关键词 Cave hill thermal and moisture transfer Darcy’s law temperaturefield PERMEABILITY
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水泵水轮机S特性区能量损失及流动特性研究
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作者 王李科 姚亮 +3 位作者 冯建军 朱国俊 卢金玲 阮辉 《水利学报》 EI CSCD 北大核心 2024年第3期344-354,366,共12页
为了调节电网的稳定性,抽水蓄能电站需要频繁启停和变换工况运行,导致水泵水轮机容易进入S特性区,机组振动增加,并网失败。本文以模型水泵水轮机为研究对象,采用熵产理论详细分析了S特性区不同工况下的能量损失规律,明确了熵产率分布与... 为了调节电网的稳定性,抽水蓄能电站需要频繁启停和变换工况运行,导致水泵水轮机容易进入S特性区,机组振动增加,并网失败。本文以模型水泵水轮机为研究对象,采用熵产理论详细分析了S特性区不同工况下的能量损失规律,明确了熵产率分布与内部流动结构的关系。结果表明:S特性区内近飞逸工况总熵产最大,约为设计工况的5.1倍,脉动熵产占据的比例接近80%,随着流量的减小,转轮熵产占比逐渐降低,活动导叶和尾水管的熵产占比增加。小流量工况转轮进口靠近下环位置首先出现了明显的漩涡,导致了活动导叶出口和转轮进口的高熵产区,随着流量进一步减小,漩涡逐渐向上冠转移,并且切向速度增大,在转轮进口形成挡水环,阻碍水流进入转轮,在无叶区内出现了环状分布的高熵产区。反水泵工况,水流在低压边与逆时针旋转的叶片撞击,导致水流很难进入叶片内部,形成了大尺度的回流涡结构;双列叶栅内充满大量涡结构,导致活动导叶吸力面的熵产率增大,并且向固定导叶传播。 展开更多
关键词 水泵水轮机 s特性 熵产理论 回流涡
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基于遗传粒子群算法的超混沌S盒设计
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作者 陆雅雯 李正权 +2 位作者 谭立容 顾斌 邢松 《江苏大学学报(自然科学版)》 CAS 北大核心 2024年第6期701-708,共8页
针对目前基于混沌系统所构造的S盒难以拥有良好密码学性能的问题,提出一种基于超混沌系统及遗传粒子群优化算法的S盒设计方案.在一维混沌映射基础上,引入正余弦函数以及指数因子,构造一个二维超混沌系统,从系统分叉图、相图、Lyapunov... 针对目前基于混沌系统所构造的S盒难以拥有良好密码学性能的问题,提出一种基于超混沌系统及遗传粒子群优化算法的S盒设计方案.在一维混沌映射基础上,引入正余弦函数以及指数因子,构造一个二维超混沌系统,从系统分叉图、相图、Lyapunov指数图进行性能分析,该混沌系统在参数范围内有着连续的超混沌区间,混沌行为复杂.通过改变混沌系统的初值、参数以及迭代次数可以动态生成S盒,随后结合粒子群优化算法和遗传算法提出一种针对S盒的遗传粒子群优化算法,将混沌系统生成的S盒作为初始种群,利用粒子群算法改进遗传算法中的交叉操作,同时结合爬山算法提出一种新的变异策略.为验证所生成S盒性能,对S盒的双射特性、非线性度、严格雪崩准则、差分均匀性及输出比特间独立性进行仿真测试,仿真结果表明:所提出的优化算法能够生成非线性度、差分均匀性、输出比特间独立性方面表现良好的S盒. 展开更多
关键词 s 超混沌系统 LYAPUNOV指数 粒子群优化算法 遗传算法 爬山算法
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The Criteria for Reducing Centrally Restricted Three-Body Problem to Two-Body Problem
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作者 Bijay Kumar Sharma 《International Journal of Astronomy and Astrophysics》 2024年第1期1-19,共19页
Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubatio... Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubation of much heavier planets such as Jupiter and Saturn if the natural satellite lies deep inside the respective host Planet Hill sphere. Each planet has a Hill radius a<sub>H</sub> and planet mean radius R<sub>P </sub>and the ratio R<sub>1</sub>=R<sub>P</sub>/a<sub>H</sub>. Under very low R<sub>1 </sub>(less than 0.006) the approximation of CRTBP (centrally restricted three-body problem) to two-body problem is valid and planet has spacious Hill lobe to capture a satellite and retain it. This ensures a high probability of capture of natural satellite by the given planet and Sun’s perturbation on Planet-Satellite binary can be neglected. This is the case with Earth, Mars, Jupiter, Saturn, Neptune and Uranus. But Mercury and Venus has R<sub>1</sub>=R<sub>P</sub>/a<sub>H</sub> =0.01 and 5.9862 × 10<sup>-3</sup> respectively hence they have no satellites. There is a limit to the dimension of the captured body. It must be a much smaller body both dimensionally as well masswise. The qantitative limit is a subject of an independent study. 展开更多
关键词 hills Radius Two-Body Problem Fixed-Point solution Lagrange Points Earth-Moon-Test Particle CRTBP
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The Magnetic Longitudinal (P-) Wave’s Propagation and Energy Models Underlying the Mechanisms of Its Capacity to Absorb Free Energy
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作者 Jianzhong Jiang Yufeng Wang 《Journal of Power and Energy Engineering》 2024年第7期39-62,共24页
The longitudinal wave term within Faraday’s law of electromagnetic induction (Faraday’s law) underwent recovery to ensure its suitability for theoretical derivation of the equation governing longitudinal electromagn... The longitudinal wave term within Faraday’s law of electromagnetic induction (Faraday’s law) underwent recovery to ensure its suitability for theoretical derivation of the equation governing longitudinal electromagnetic (LEM) waves. The revised Maxwell’s equations include the crucial parameters being the attenuation time constants of magnetic vortex potential and electric vortex potential generated by external electromagnetic field within the propagation medium. Specific expressions for them are obtained through theoretical analysis. Subsequently, a model for propagating magnetic P-wave generated by the superposition of a left-handed photo and a right-handed photon in a vacuum is formulated based on reevaluated total current law and revised Faraday’s law, covering wave equations, energy equation, as well as propagation mode involving mutual induction and conversion between scalar magnetic field and vortex electric field. Furthermore, through theoretical derivations centered around magnetic P-wave, evidence was presented regarding its ability to absorb huge free energy through the entangled interaction between zero-point vacuum energy field and the torsion field produced by the vortex electric field. 展开更多
关键词 QED (Quantum Electrodynamics) Energy Wave and TEM (Transverse Electromagnetic) Wave Magnetic P-Wave Modified Faraday’s Law of Electromagnetic Induction Electric/Magnetic vortex Potential Zero-Point Vacuum Energy
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Hill’s方程的Magnus积分 被引量:2
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作者 王博 邓子辰 +1 位作者 李文成 徐晓建 《西北工业大学学报》 EI CAS CSCD 北大核心 2011年第6期988-991,共4页
基于Magnus积分方法,针对Hamilton系统下卫星编队绕飞轨道误差问题,对二阶Hill’s方程进行了降阶变换和数值模拟。通过引进新状态变量将二阶动力学系统表示为一阶动力学系统,从而保留了原二阶动力学系统的典则性质。采用Magnus积分方法... 基于Magnus积分方法,针对Hamilton系统下卫星编队绕飞轨道误差问题,对二阶Hill’s方程进行了降阶变换和数值模拟。通过引进新状态变量将二阶动力学系统表示为一阶动力学系统,从而保留了原二阶动力学系统的典则性质。采用Magnus积分方法求解一阶系统方程,与传统四阶Runge-Kutta方法相比,该方法计算简单,精度高。文中采用该方法分析了两种绕飞半径的轨道误差问题,分析结果表明该方法具有良好的精度和稳定性。 展开更多
关键词 hills方程 Magnus方法 李群积分 HAMILTON系统 卫星编队飞行
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A version of Hill's lemma for Cosserat continuum 被引量:3
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作者 Xikui Li Qipeng Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第4期499-506,共8页
On the basis of Hill's lemma for classical Cauchy continuum, a version of Hill's lemma for micro-macro homogenization modeling of heterogeneous Cosserat continuum is presented in the flame of average-field theory. T... On the basis of Hill's lemma for classical Cauchy continuum, a version of Hill's lemma for micro-macro homogenization modeling of heterogeneous Cosserat continuum is presented in the flame of average-field theory. The admissible boundary conditions required to prescribe on the representative volume element for the modeling are extracted and discussed to ensure the satisfaction of Hill-Mandel energy condition and the first-order average field theory. 展开更多
关键词 hill's lemma hill-Mandel condition Cosserat continuum Average-field theory RVE boundary conditions
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A microstructure-based analysis of cyclic plasticity of pearlitic steels with Hill's self-consistent scheme incorporating general anisotropic Eshelby tensor 被引量:2
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作者 Xuesong Long Xianghe Peng Wenli Pi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第1期91-99,共9页
A pearlitic steel is composed of numerous pearlitic colonies with random orientations, and each colony consists of many parallel lamellas of ferrite and cementite. The constitutive behavior of this kind of materials m... A pearlitic steel is composed of numerous pearlitic colonies with random orientations, and each colony consists of many parallel lamellas of ferrite and cementite. The constitutive behavior of this kind of materials may involve both inherent anisotropy and plastic deformation induced anisotropy. A description of the cyclic plasticity for this kind of dual-phase materials is proposed by use of a microstructure-based constitutive model for a pearlitic colony, and the Hill's self-consistent scheme incorporating anisotropic Eshelby tensor for ellipsoidal inclusions. The corresponding numerical algorithm is developed. The responses of pearlitic steel BS 11 and single-phase hard-drawn copper subjected to asymmetrically cyclic loading are analyzed. The analytical results agree very well with experimental ones. Compared with the results using isotropic Eshelby tensor, it is shown that the isotropic approximation can provide acceptable overall responses in a much simpler way. 展开更多
关键词 Pearlitic steel hill's self-consistent scheme Eshelby tensor Cyclic plasticity Microstructure-basedanalysis
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Constant Power Model in Arm Rotation—A New Approach to Hill’s Equation 被引量:1
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作者 Ahti Rahikainen Mikko Virmavirta 《World Journal of Mechanics》 2014年第6期157-169,共13页
The purpose of this study was to further develop the constant power model of a previous study and to provide the final solution of Hill’s force-velocity equation. Forearm and whole arm rotations of three different su... The purpose of this study was to further develop the constant power model of a previous study and to provide the final solution of Hill’s force-velocity equation. Forearm and whole arm rotations of three different subjects were performed downwards (elbow and shoulder extension) and upwards (elbow and shoulder flexion) with maximum velocity. These arm rotations were recorded with a special camera system and the theoretically derived model of constant maximum power was fitted to the experimentally measured data. The moment of inertia of the arm sectors was calculated using immersion technique for determining accurate values of friction coefficients of elbow and whole arm rotations. The experiments of the present study verified the conclusions of a previous study in which theoretically derived equation with constant maximum power was in agreement with experimentally measured results. The results of the present study were compared with the mechanics of Hill’s model and a further development of Hill’s force-velocity relationship was derived: Hill’s model was transformed into a constant maximum power model consisting of three different components of power. It was concluded that there are three different states of motion: 1) the state of low speed, maximal acceleration without external load which applies to the hypothesis of constant moment;2) the state of high speed, maximal power without external load which applies to the hypothesis of constant power and 3) the state of maximal power with external load which applies to Hill’s equation. This is a new approach to Hill’s equation. 展开更多
关键词 Arm Movement Force-Velocity Relationship Muscle Power hills Equation
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Exploration of the Development of Science and Technology in Historical Turbulence:A Review on the Book Series Vortex Dynamics of the Development of Science and Technology
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作者 WANG Fang 《Chinese Annals of History of Science and Technology》 2021年第2期187-192,共6页
Review of Baturin,Yuri M.[Батурин,ЮрийМ.],ed.2018–19.Вихреваядинамикаразвитинаукиитехники[Vortex Dynamics of the Development of Science and Technology].3 vols2124 pages... Review of Baturin,Yuri M.[Батурин,ЮрийМ.],ed.2018–19.Вихреваядинамикаразвитинаукиитехники[Vortex Dynamics of the Development of Science and Technology].3 vols2124 pages.Moscow:ИИЕТРАН[IHST RAS].Baturin,Yuri M.,ed.2018.Турбулентнаяисториянаукиитехники[Turbulent History of Science and Technology]. 展开更多
关键词 TURBULENT vortex s.
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Arnold Tongues for Discrete Hill’s Equation
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作者 José Guillermo Rodríguez Servín M. Joaquin Collado 《Applied Mathematics》 2017年第12期1859-1882,共24页
In this work we study two types of Discrete Hill’s equation. The first comes from the discretization process of a Continuous-time Hill’s equation, we called Discretized Hill’s equation. The Second is a naturally ob... In this work we study two types of Discrete Hill’s equation. The first comes from the discretization process of a Continuous-time Hill’s equation, we called Discretized Hill’s equation. The Second is a naturally obtained in Discrete-Time and will be called Discrete-time Hill’s equation. The objective of discretization is preserving the continuous-time behavior and we show this property. On the contrary a completely different dynamic property was found for the Discrete-Time Hill’s equation. At the end of the paper is shown that both types share the nonoscillatory behavior of solutions in the 0-th Arnold Tongue. 展开更多
关键词 ARNOLD Tongues DIsCRETE hills EQUATION MONODROMY MATRIX Discretized HAMILTONIAN
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Analysis of Vortex Motion in Porous Media
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作者 Beant Singh Chanpreet Singh 《Journal of Electronics Cooling and Thermal Control》 2012年第2期32-34,共3页
In vortex motion fluid moves in curve path and the stream lines are curved. When the fluid flows between curved stream line, the centrifugal forces are setup which is counter balanced by pressure forces acting in the ... In vortex motion fluid moves in curve path and the stream lines are curved. When the fluid flows between curved stream line, the centrifugal forces are setup which is counter balanced by pressure forces acting in the radial direction. The vortex motion has two types of curved motion. The first type called free vortex type, the fluid moves due to its own natural effect but energy is not added to fluid when moving in curved path. The second type called forced vortex, in which energy is added to fluid. A two dimensional steady laminar free convective flow of viscous incompressible flow in porous media voids is considered. In this paper the motion of fluid is studied while moving in the porous media. It is studied that the motion of the fluid in the porous media is vortex motion at the low Reynolds’s number, where the motion is laminar motion and the fluid obeys the laws of vortex motion. 展开更多
关键词 POROUs MEDIA vortex MOTION Reynoldss NUMBER
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Symbols In HEMINGWAY'S “Hills Like White Elephants” Story commentary
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作者 Wang Zhenguo 《河西学院学报》 1988年第2期96-99,105,共5页
HEMINGWAY’s story,“Hills Like White Elephants”,is about lovingrelationships between an American man and a girl.As lovers,they are in-timate,with the girl in the state of pregnancy.The story is told from the objecti... HEMINGWAY’s story,“Hills Like White Elephants”,is about lovingrelationships between an American man and a girl.As lovers,they are in-timate,with the girl in the state of pregnancy.The story is told from the objective point of view.It takes place duringa 40-minute wait between trains.What lies behind them is indicated by thelabels on their bags.What lies ahead of them implies entire force and dir-ection of the story.It is at the station that a decision will be made 展开更多
关键词 hills Like White Elephants story commentary symbols In HEMINGWAY’s
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Theoretical and Experimental Analysis of Vortex Origin
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作者 Pedro Guido Aldana Jose Roberto Mercado 《Journal of Mathematics and System Science》 2013年第5期251-261,共11页
Several investigations refer to the issue of creation and identification of vortices in flows with different regime and presence of obstacles. Reasons have to do with the crucial role that vortices play in nature and ... Several investigations refer to the issue of creation and identification of vortices in flows with different regime and presence of obstacles. Reasons have to do with the crucial role that vortices play in nature and industrial processes (sediment transport, mixing, radiation, noise, etc.). Despite the contributions, further work is needed in order to perform more analysis of the mathematical arguments used to explain this phenomenon. In this idea order, the paper presents some advances in mathematical analysis and experimental results. In the first section, we do a description of the fluid motion from a fractional view through a sequence of three steps: Darcy's law, Navier-Stokes equations and Reynolds equations. Next, a representation of the temporal change of kinetic energy is found, which allows the possibility of the two signs. We obtain a description of the process of vortex creation. A length that represents the transition between flow and vortex intensity is found; then a succession of lengths is established that allows scaling from micro to macro. In the second section, experimental results are present; we consider vortex creation and its detection upstream of a bed form similar to that found in rivers, installed in an open channel, equipped with a water circulation system. For vortex detection, a methodology based on the particle image velocimetry PIV technique is proposed. So, we fulfill two objectives: vortex identification and its passage frequencies behind the bed form installed in the channel. Such procedure allows a computer process time reduction in vortices identification task. 展开更多
关键词 Navier-stokes fractional equation Darcy's law vortex detection particle image velocimetry open channel bed form.
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一种提高S盒非线性度的新算法 被引量:4
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作者 高胜 马文平 +1 位作者 郭娜 严亚俊 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2010年第6期1017-1021,共5页
S盒是构成分组密码算法重要的非线性部件.利用交换S盒两个输出向量来达到提高其非线性度的思想,提出一个通过交换S盒3个输出向量来提高其非线性度的方法,即三点爬山法.该方法简洁且执行效率较高,而且在William Millan两点爬山法不能提高... S盒是构成分组密码算法重要的非线性部件.利用交换S盒两个输出向量来达到提高其非线性度的思想,提出一个通过交换S盒3个输出向量来提高其非线性度的方法,即三点爬山法.该方法简洁且执行效率较高,而且在William Millan两点爬山法不能提高S盒非线性度的情况下,能进一步改进非线性度.在此基础上,提出一个基于爬山算法的S盒优化算法,弥补了原有算法不能进一步改善非线性度的缺陷.对一些小变量S盒的实验结果验证了该算法的正确性和高效性. 展开更多
关键词 s 非线性度 WALsH变换 爬山算法
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S形进气道流动控制数值模拟研究 被引量:5
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作者 张丽芬 刘振侠 +1 位作者 郭东明 王小峰 《空气动力学学报》 EI CSCD 北大核心 2009年第2期240-245,共6页
采用CFD技术,结合试飞数据,对某S形进气道进行了加涡流发生器的流动控制数值模拟研究。着重分析了三个不同位置加涡流发生器后,进气道内部二次流的发展;之后比较了不加涡流发生器及不同位置加涡流发生器时进气道出口总压恢复、畸变等情... 采用CFD技术,结合试飞数据,对某S形进气道进行了加涡流发生器的流动控制数值模拟研究。着重分析了三个不同位置加涡流发生器后,进气道内部二次流的发展;之后比较了不加涡流发生器及不同位置加涡流发生器时进气道出口总压恢复、畸变等情况。结果表明涡流发生器明显地影响着进气道内部二次流的发展变化,涡流发生器对进气道出口周向稳态总压畸变有较大程度改善,但是对于提高总压恢复效果不明显。 展开更多
关键词 s形进气道 二次流 流动控制 涡流发生器
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S系列新翼型风力机叶尖近尾迹区域流场数值计算与分析 被引量:4
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作者 代元军 汪建文 +2 位作者 吴伟民 张立茹 赵宏宇 《太阳能学报》 EI CAS CSCD 北大核心 2014年第2期195-201,共7页
以S系列新翼型为例,针对设计风速最佳攻角含有叶尖涡的复杂流动,提出一种采用分区域过渡层网格的方法来改善叶尖涡模拟的新网格生成策略。这种利用过渡层网格从叶片的贴体网格区域向中部加密网格区域中捕捉叶尖涡形成的位置和大小,通过... 以S系列新翼型为例,针对设计风速最佳攻角含有叶尖涡的复杂流动,提出一种采用分区域过渡层网格的方法来改善叶尖涡模拟的新网格生成策略。这种利用过渡层网格从叶片的贴体网格区域向中部加密网格区域中捕捉叶尖涡形成的位置和大小,通过控制网格梯度变化能获得高精度计算结果。数值计算和分析表明:该网格能合理捕捉到S系列新翼型叶尖涡的细节变化信息以及叶轮表面压力分布的细节变化特性,发现了风力机叶尖涡在初期向内迁移的现象。证明该网格生成策略合理有效。 展开更多
关键词 风力机 s系列新翼型 NACA系列传统翼型 叶尖涡 过渡层网格 网格梯度
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S弯进气道流动控制技术的试验研究 被引量:3
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作者 张振 刘丹 黄浩 《应用力学学报》 CAS CSCD 北大核心 2014年第2期201-205,307-308,共5页
在低速风洞中采用微型叶片作为涡流发生器对某S弯进气道进行流动控制,通过风洞试验研究了微型叶片的不同参数(包括叶片高度、轴向位置、安装组数)对进气道气动特性的影响。试验测量了来流风速V=60m/s、模型攻角α=8°的条件下有/无... 在低速风洞中采用微型叶片作为涡流发生器对某S弯进气道进行流动控制,通过风洞试验研究了微型叶片的不同参数(包括叶片高度、轴向位置、安装组数)对进气道气动特性的影响。试验测量了来流风速V=60m/s、模型攻角α=8°的条件下有/无微型导流叶片时进气道出口截面的总压和静压分布,并由此计算得到进气道出口截面的总压恢复系数和畸变指数。试验结果表明:微型叶片的不同参数(包括叶片高度、轴向位置、安装组数)对进气道流动有明显影响;通过在进气道第一弯道处安装合适高度和组数的微型叶片涡发生器,可以明显改善进气道出口流动;在现有的试验条件下,叶片高度h/Ri=0.02、轴向位置Xvg/Ri=1、组数Nvg=8是相对较优的流动控制方案,主要表现为:与未安装微型叶片相比,进气道流量系数φ=0.8时出口畸变指数降低了0.051,总压恢复系数提高了0.007。 展开更多
关键词 s弯进气道 流动控制 微型叶片 涡流发生器 风洞试验
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