基于拉格朗日力学的末敏弹稳态扫描阶段动力学模型

末敏弹的稳态扫描阶段为弹上扫描装置提供了一个稳定的平台,需要同时达到下降速度、旋转速度以及子弹扫描角的稳定。为了便于分析旋转伞和子弹的运动姿态,采用拉格朗日力学方法建立了伞弹系统的七自由度模型。与欧拉方法相比,该方法回避了伞-弹之间的复杂约束力,并且仿真过程中不会出现奇点。最后通过算例,分析了伞弹系统稳态扫描阶段的弹道特性,得到了各弹道参数达到稳定状态的时间,为末敏弹的优化设计提供了思路。     

无源毫米波末敏弹

论述了八毫米辐射计的末敏弹的工作原理和设计原则．在搜索过程中末敏弹吊在降落伞下，一面旋转一面以某个适当的速度下降，使辐射计的天线以螺旋线形扫描目标区域。在此有效面积内探测目标，并以很高的命中概率摧毁目标。在天线温度对比度理论计算的基础上研制出探测和定位算法，给出了计算机仿真打靶试验的结果。     

无源毫米波末敏弹

论述了八毫米辐射计的末敏弹的工作原理和设计原则，在搜索过程中末敏弹吊在降伞下，一面旋转一面以某个适当的速度下降，使辐射计的天线以螺旋线形扫描目标区域，在此有效面积内探测目标，并以很高的命中概率摧毁目标，在天线温度对比度理论计算的基础上研制出探测和定位算法，给出了计算机仿真打靶试验的结果。     

末敏弹被动特性的干扰技术研究

介绍了末敏弹的攻击过程,并且在详细分析毫米波辐射计被动探测工作模式原理的基础上,设计了欺骗式脉冲压制干扰和欺骗式连续波压制干扰两种干扰样式,并且分别进行了仿真。仿真结果表明,欺骗式的干扰方式会造成末敏弹辐射计在一定程度上的识别率下降,研究结果对工程实践具有指导性。     

TSP系统全充满旋转减速伞运动特性的研究

末敏弹是新一代反坦克武器。该文对末敏弹系统全充满旋转减速伞的运动特性进行研究，首行从流体动能的概念引入降落伞的附加质量和附加惯性矩，从完整系统的广义欧拉运动方程建立降落伞的运动模型；然后与末敏弹系统完整的运动方程组联立求解。     

两种典型尾翼形状对无伞末敏弹气动特性的影响

为研究尾翼形状对双翼无伞末敏弹减速导旋性能的影响,分别对平板尾翼和S-C形尾翼结构末敏弹的气动特性进行研究。基于计算流体力学方法,获得了末敏弹气动外形的流场特性、表面压力分布和阻力系数、升力系数和转动力矩系数随攻角变化的规律。通过自由飞行试验对平板尾翼和S-C尾翼末敏弹进行了动态气动特性研究。数值计算结果显示,平板尾翼和S-C尾翼模型阻力系数在6～9间,其增阻效果明显;两模型升力系数均呈负线性变化,尾翼形状对升力系数影响较小;尾翼形状对转动力矩系数影响明显,平板尾翼几无转动力矩产生,S-C尾翼转动力矩相对较大并随攻角增加而减小。自由飞行试验表明,S-C尾翼结构自由飞行状态下增阻效果好于平板尾翼,并可使弹体获得转动力矩而维持稳定转速,能够实现稳态扫描运动。平板尾翼末敏弹自由飞行稳定性差。     

武器装备的新宠——智能弹药

 二十年前,我有幸步入智能弹药工程技术领域,成为我国该领域拓荒群体中的一员.从那时起,我便与智能弹药的重要分支——末敏弹药结下了不解之缘,它的原理之新颖、内涵之丰富、效能之卓越、挑战之巨大极大地吸引并激励着我和我的团队.之后的二十年间,我和我的团队走过了极为艰难曲折的历程,共享了无数次失败、成功、失望、希望、痛苦、喜悦,以锲而不舍的奋斗精神创造性地攻克了末敏弹的关键技术,成功地开辟了我国末敏弹技术领域,不仅自主研制出具有世界一流水平的我国第一个末敏弹武器系统,而且形成了我国自己的末敏弹设计、分析、仿真、试验、制造与验收的方法和理论体系,使我国跻身于少数掌握这一技术并能自主研发该类装备的国家之列.那么,末敏弹是一种什么样的弹药？为什么说它是智能弹药？     

浅析末敏弹几个设计参数的确定

该文简要地分析了末敏弹的抛撒过程及弹道规律,重点讨论了末敏弹的下降速度、旋转速度以及与反应时间的关系,以供设计末敏弹药时参考。     

一种基于落角约束的偏置比例导引律

为增大反坦克导弹的命中落角,提高毁伤效果,建立了击顶弹道末制导段的弹目相对运动模型,提出了一种基于落角约束的偏置比例导引律,并研究了落角约束对导引律法向过载的影响,通过设计盲区控制方案减小了命中点法向过载,最后基于导引弹道仿真与传统比例导引律以及两种其它类型的改进比例导引律进行了仿真比较. 仿真结果表明,该偏置比例导引律控制落角能力较强,同时具有较高的命中精度.      

影响子母弹终端效应的关键参数及其搜索方法

为解决航空子母弹抛撒点抛撒高度、速度等参数设定问题,基于一种子弹单圈多段排布的航空子母弹模型,通过建立子弹的外弹道方程,研究它的地面散布并且寻找其散布规律；然后根据在实战中要求的所要摧毁的目标形状、面积,从子母弹作战效能角度出发,提出一种搜索算法,用该算法能搜索出覆盖目标范围所要求的子母弹的几种抛撒参数.仿真验证表明:该算法能够使子弹有效地覆盖目标,最大误差2.5％,提高了航空子母弹的作战效能.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with