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对流密码Helix的代数故障攻击 被引量:1
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作者 陈浩 王韬 +2 位作者 刘会英 周平 冯晓云 《计算机工程与设计》 CSCD 北大核心 2014年第2期445-450,共6页
对Helix流密码算法首次提出一种代数故障攻击方法。将代数攻击和差分故障攻击结合,对Helix算法中的模加运算结构提出了一种通用的代数故障攻击模型,通过选择明文和故障注入,构建了Helix在该模型下的代数方程组,使用CryptoMiniSAT解析器... 对Helix流密码算法首次提出一种代数故障攻击方法。将代数攻击和差分故障攻击结合,对Helix算法中的模加运算结构提出了一种通用的代数故障攻击模型,通过选择明文和故障注入,构建了Helix在该模型下的代数方程组,使用CryptoMiniSAT解析器求解方程组系统恢复密钥信息。实验结果表明,580次故障注入即可恢复Helix工作密钥除最高位外的248比特信息,剩余8比特密钥信息可以通过穷举得到。针对模2n加运算所提出代数故障攻击模型可以为其他流密码安全性分析提供一定的参考。 展开更多
关键词 差分故障攻击 代数攻击 代数故障攻击 模加方程 HELIX
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The training process: Planning for strength-power training in track and field. Part 1: Theoretical aspects 被引量:3
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作者 Brad H. DeWeese Guy Hornsby +1 位作者 Meg Stone Michael H. Stone 《Journal of Sport and Health Science》 SCIE 2015年第4期308-317,共10页
The process of strength-power training and the subsequent adaptation is a multi-factorial process. These factors range from the genetics and morphological characteristics of the athlete to how a coach selects, orders,... The process of strength-power training and the subsequent adaptation is a multi-factorial process. These factors range from the genetics and morphological characteristics of the athlete to how a coach selects, orders, and doses exercises and loading patterns. Consequently, adaptation from these training factors may largely relate to the mode of delivery, in other words, programming tactics. There is strong evidence that the manner and phases in which training is presented to the athlete can make a profound difference in performance outcome. This discussion deals primarily with block periodization concepts and associated methods of programming for strength-power training within track and field. 2015 Production and hosting by Elsevier B.V. on behalf of Shanghai University of Sport. 展开更多
关键词 Periodization Strength-power training Track and field Training process
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Numerical modeling dynamic process of multi-feed microwave heating of industrial solution media 被引量:4
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作者 杨彪 孙俊 +7 位作者 李玮 彭金辉 李幼灵 罗会龙 郭胜惠 张竹敏 苏鹤州 史亚鸣 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3192-3203,共12页
The exothermic efficiency of microwave heating an electrolyte/water solution is remarkably high due to the dielectric heating by orientation polarization of water and resistance heating by the Joule process occurred s... The exothermic efficiency of microwave heating an electrolyte/water solution is remarkably high due to the dielectric heating by orientation polarization of water and resistance heating by the Joule process occurred simultaneously compared with pure water.A three-dimensional finite element numerical model of multi-feed microwave heating industrial liquids continuously flowing in a meter-scale circular tube is presented.The temperature field inside the applicator tube in the cavity is solved by COMSOL Multiphysics and professional programming to describe the momentum,energy and Maxwell's equations.The evaluations of the electromagnetic field,the temperature distribution and the velocity field are simulated for the fluids dynamically heated by singleand multi-feed microwave system,respectively.Both the pilot experimental investigations and numerical results of microwave with single-feed heating for fluids with different effective permittivity and flow rates show that the presented numerical modeling makes it possible to analyze dynamic process of multi-feed microwave heating the industrial liquid.The study aids in enhancing the understanding and optimizing of dynamic process in the use of multi-feed microwave heating industrial continuous flow for a variety of material properties and technical parameters. 展开更多
关键词 microwave with multi-feed heating industrial flow dynamical process numerical computation solution media
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A Monte Carlo Model of Light Propagation in Nontransparent Tissue 被引量:2
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作者 姚建铨 朱水泉 +1 位作者 胡海峰 王瑞康 《Transactions of Tianjin University》 EI CAS 2004年第3期209-213,共5页
To sharpen the imaging of structures, it is vital to develop a convenient and efficient quantitative algorithm of the optical coherence tomography (OCT) sampling. In this paper a new Monte Carlo model is set up and ho... To sharpen the imaging of structures, it is vital to develop a convenient and efficient quantitative algorithm of the optical coherence tomography (OCT) sampling. In this paper a new Monte Carlo model is set up and how light propagates in bio-tissue is analyzed in virtue of mathematics and physics equations. The relations,in which light intensity of Class 1 and Class 2 light with different wavelengths changes with their permeation depth,and in which Class 1 light intensity (signal light intensity) changes with the probing depth, and in which angularly resolved diffuse reflectance and diffuse transmittance change with the exiting angle, are studied. The results show that Monte Carlo simulation results are consistent with the theory data. 展开更多
关键词 optical coherence tomography(OCT) mathematics and physics equations bio-tissue Monte Carlo model photon cluster weight
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Vector refinement equation and subdivision schemes in Lp spaces
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作者 吴正昌 《Journal of Zhejiang University Science》 CSCD 2002年第3期332-338,共7页
In this paper we will first prove that the nontrivial L p solutions of the vector refinement equation exist if and only if the corresponding subdivision scheme with a suitable initial function converges in L p... In this paper we will first prove that the nontrivial L p solutions of the vector refinement equation exist if and only if the corresponding subdivision scheme with a suitable initial function converges in L p without assumption of the stability of the solutions. Then we obtain a characterization of the convergence of the subdivision scheme in terms of the mask. This gives a complete answer to the existence of L p solutions of the refinement equation and the convergence of the corresponding subdivision schemes. 展开更多
关键词 Refinement equations Subdivision schemes Joint spectral radius.
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A simulation of diesel hydrotreating process with real component method 被引量:1
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作者 Zengzhi Du Chunxi Li +1 位作者 Wei Sun Jianhong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第5期780-788,共9页
Computer simulation is a good guide and reference for development and research on petroleum refining processes. Traditionally, pseudo-components are used in the simulation, in which their physical properties are estim... Computer simulation is a good guide and reference for development and research on petroleum refining processes. Traditionally, pseudo-components are used in the simulation, in which their physical properties are estimated by empirical relations and cannot be associated with actual chemical reactions, as no molecular structure is available for pseudo-components. This limitation can be overcome if real components are used. In this paper, a real component based method is proposed for the simulation of a diesel hydrotreating process by using the software of Unisim Design. This process includes reaction units and distillation units. The chemical reaction network is established by analyzing the feedstock. The feedstock is characterized by real components, which are obtained based on true boiling point curve. Simulation results are consistent with actual data. 展开更多
关键词 Simulation Real components Diesel hydrotreating True boiling point
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The Principle of Square Hole Machining and It's Tooling Structure Design
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作者 Jinxia NIU 《International Journal of Technology Management》 2015年第2期7-8,共2页
In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and pro... In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel. 展开更多
关键词 Abstract: In order to meet the rapid needs of processing square hole in mechanical equipment the paper expounds the square hole processing method: planetary wheel method and analyze the principle of tooling structure and process with computer graphics parameters design. The results that as long as the appropriate parameters using the above method not only can punch the square hole can also be processed triangle the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel. Keywords: Square hole processing Planet wheel Lelo triangle Square hole drilling
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A decoupled procedure for convection-radiation simulation in scramjets 被引量:6
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作者 WANG Jing Ying GAO Zhen Xun +1 位作者 LEE Chun Hian ZHANG Hui Qiang 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第12期2551-2566,共16页
Following an order analysis of key parameters, a decoupled procedure for simulation of convection-radiation heat transfer problems in supersonic combustion ramjet(scramjet) engine was developed. The radiation module o... Following an order analysis of key parameters, a decoupled procedure for simulation of convection-radiation heat transfer problems in supersonic combustion ramjet(scramjet) engine was developed. The radiation module of the procedure consisted of Perry 5GG weighted sum gray gases model for spectral property calculation and discrete ordinates method S4 scheme for radiative transfer computation, while the flow field was computed using the Favrè average conservative Navier-Stokes(N-S) equations, in conjunction with Menter's k-ω SST two-equation model. A series of 2D supersonic nonreactive turbulent channel flows of radiative participants with selective parameters were simulated for validation purpose. Radiative characteristics in DLR hydrogen fueled and NASA SCHOLAR ethylene fueled scramjets were numerically studied using the developed procedure. The results indicated that the variations of spatial distributions of the radiative source and total absorption coefficient are highly consistent with those of the temperature and radiative participants, while the spatial distribution of the incident radiation spreads wider. It also demonstrated that the convective heating is significantly affected by the complexity of the flow field, such as the shock wave/boundary layer interactions, while the radiative heating is simply an integral effect of the whole flow field. Although the radiative heating in the combustion chambers reaches a certain level, an order of magnitude of 10 k W/m2, it still contributes little to the total heat transfer(<7%). 展开更多
关键词 SCRAMJET radiative heating convective heating turbulent combustion decoupled procedure
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Hypergeometric equations and weighted projective spaces
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作者 CORTI Alessio GOLYSHEV Vasily 《Science China Mathematics》 SCIE 2011年第8期1577-1590,共14页
We compute the Hodge numbers of the polarised(pure) variation of Hodge structure V = grn-1WRn-1f!Z of the Landau-Ginzburg model f:Y → C mirror-dual to a weighted projective space wPn in terms of a variant of Reid'... We compute the Hodge numbers of the polarised(pure) variation of Hodge structure V = grn-1WRn-1f!Z of the Landau-Ginzburg model f:Y → C mirror-dual to a weighted projective space wPn in terms of a variant of Reid's age function of the anticanonical cone over wPn.This implies,for instance,that wPn has canonical singularities if and only if hn-1,0V = 1.We state a conjectural formula for the Hodge numbers of general hypergeometric variations.We show that a general fibre of the Landau-Ginzburg model is birational to a Calabi-Yau variety if and only if a general anticanonical section of wP is Calabi-Yau.We analyse the 104 weighted 3-spaces with canonical singularities,and show that a general anticanonical section is not a K3 surface exactly in those 9 cases where a generic fibre of the Landau-Ginzburg model is an elliptic surface of Kodaira dimension 1. 展开更多
关键词 mirror symmetry variations of Hodge structures hypergeometric functions weighted projective spaces Landau-Ginzburg models
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From Dislocation Motion to an Additive Velocity Gradient Decomposition, and Some Simple Models of Dislocation Dynamics
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作者 Amit ACHARYA Xiaohan ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2015年第5期645-658,642,共14页
A mathematical theory of time-dependent dislocation mechanics of unrestricted geometric and material nonlinearity is reviewed. Within a "small deformation" setting, a suite of simplified and interesting mode... A mathematical theory of time-dependent dislocation mechanics of unrestricted geometric and material nonlinearity is reviewed. Within a "small deformation" setting, a suite of simplified and interesting models consisting of a nonlocal Ginzburg Landau equation, a nonlocal level set equation, and a nonlocal generalized Burgers equation is derived.In the finite deformation setting, it is shown that an additive decomposition of the total velocity gradient into elastic and plastic parts emerges naturally from a micromechanical starting point that involves no notion of plastic deformation but only the elastic distortion,material velocity, dislocation density and the dislocation velocity. Moreover, a plastic spin tensor emerges naturally as well. 展开更多
关键词 Dislocations PLASTICITY Continuum mechanics Finite deformation
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Lattice Boltzmann Simulation of Mixed Convection Heat Transfer in a Driven Cavity with Non-uniform Heating of the Bottom Wall
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作者 Soufiene Bettaibi Ezeddine Sediki +1 位作者 Frdric Kuznik Sauro Succi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第1期91-100,共10页
The goal of this article is to study numerically the mixed convection in a differentially heated rid-driven cavity with non-uniform heating of the bottom wall. The velocity field is solved by a hybrid scheme with mult... The goal of this article is to study numerically the mixed convection in a differentially heated rid-driven cavity with non-uniform heating of the bottom wall. The velocity field is solved by a hybrid scheme with multiple relaxation time Lattice Boltzmann (MRT-LBM) model, while the temperature field is obtained by resolution of the energy balance equation using the finite difference method (FDM). First, the model is checked and validated using data from the riterature. Validation of the present resuJts with those available in the literature shows a good agreement. A good efficiency in time simulation is confirmed. Thereafter, the model has been applied to mixed convection in a driven cavity with non-uniform heating wall at the fixed Grashof number Gr = 106. It is found that, the heat transfer is weakened as the Richardson number is augmented. For Gr = 106, we note the appearance of secondary vortices at different positions of the cavity corners. 展开更多
关键词 lattice Boltzmann method (LBM) finite difference method (FDM) heated Lid-driven cavity mixed convection non-uniform heating wall
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EFFICIENT ESTIMATION OF SEEMINGLY UNRELATED ADDITIVE NONPARAMETRIC REGRESSION MODELS
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作者 YUAN Yuan YOU Jinhong ZHOU Yong 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2013年第4期595-608,共14页
This paper is concerned with the estimating problem of seemingly unrelated(SU)nonparametric additive regression models.A polynomial spline based two-stage efficient approach is proposed to estimate the nonparametric c... This paper is concerned with the estimating problem of seemingly unrelated(SU)nonparametric additive regression models.A polynomial spline based two-stage efficient approach is proposed to estimate the nonparametric components,which takes both of the additive structure and correlation between equations into account.The asymptotic normality of the derived estimators are established.The authors also show they own some advantages,including they are asymptotically more efficient than those based on only the individual regression equation and have an oracle property,which is the asymptotic distribution of each additive component is the same as it would be if the other components were known with certainty.Some simulation studies are conducted to illustrate the finite sample performance of the proposed procedure.Applying the proposed procedure to a real data set is also made. 展开更多
关键词 Additive structure asymptotic normality nonparametric modelling polynomial spline seemingly unrelated regression two-stage estimation.
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