德杰尼斯五后问题泛化研究

在德杰尼斯五后问题求解方法基础上,给出了2p×2p棋盘坐标表示,定义了方环和马步格,并利用皇后控制数或剩余控制数、皇后最佳(极佳)位置或剩余最佳(极佳)位置,以及棋盘对称性,得到了德杰尼斯五后问题泛化求解定理和便于求解的简化定理.     

德杰尼斯五后问题求解方法

给出了棋盘坐标表示,定义了皇后控制数或剩余控制数,以及皇后最佳(极佳)或剩余最佳(极佳)位置的概念.利用棋盘对称性,通过有效的计算,先求出了五后问题的3个基础解,进而得到了全部24个解及其图示,并首次给出了最少放置5个而不是4个皇后的证明,以及解的完备性证明.     

一类排列实现与皇后控制问题求解

在回溯实现从n个不同元素取m个与另n-m个相同元素的排列基础上,求解m个皇后控制n×n棋盘问题,推广了著名的高斯八皇后问题.     

奇数网格(或棋盘)德杰尼斯问题解法

在德杰尼斯五后问题泛化研究基础上,给出了(2p+1)×(2p+1)奇数网格坐标表示,定义了解首格集,利用皇后控制或剩余控制数、马步格、解首格集,以及图形对称性,得到了奇数网格(或棋盘)德杰尼斯问题求解定理和求解方法,并给出了3×3网格、5×5网格和7×7网格德杰尼斯问题的1个、3个和24个基础解及其图示.结果表明奇数网格(或棋盘)德杰尼斯问题是网格优化管控问题之一,具有一定的理论价值和应用价值.     

吸波材料地雷壳体防远距离雷达探测特性

为降低雷场的雷达侦察发现概率,提高地雷的障碍效果和生存能力,研究了微波吸收材料新型地雷壳体以提高防雷达探测性能,讨论了地雷目标雷达散射特性。当微波从壳体顶部或正侧面照射时,雷达散射截面(RCS)较强。采用羰基铁和铝合金粉为吸收剂设计和制作了微波吸收材料,在2~18GHz频率内的微波吸收衰减超过10dB。选用不锈钢纤维和羰基铁粉并采用注塑工艺制作了具有电磁屏蔽和微波吸收性能的地雷壳体样品。合成孔径雷达(SAR)探测实验结果表明:当微波从壳体顶部或正侧面照射时,RCS在8~12GHz频率内的微波衰减达到10dB。     

综合信息

科技智力游戏好玩的数学——棋盘上的数学下棋是最古老,也是拥有最广泛的爱好者的游戏,其形式也多种多样。据考证,我国的围棋是世界上历史最悠久的一种棋类。能和围棋相媲美的国际象棋则起源于印度人在7世纪左右所发明的游戏“恰多兰加”(Chaturanga),最初是由4个人分坐4个方向对弈。人们从国际象棋演绎出了许多有趣的数学问题,其中最著名的一个是“高斯八皇后问题”。下面我们给出的问题也是跟皇后有关的。在国际象棋中,皇后是一个威力很大的棋子。她可以“横冲直撞”(在水平或垂直方向上走任意步数),也可以“斜刺冲杀”(在±45°对角线上…     

倒格矢空间里的布喇格反射式的深入讨论

本文从晶体平移对称性出发引出倒格子概念,介绍了倒格子与正格子之间对应的关系,加深对倒格子的认识,并对倒格矢空间里的布喇格反射公式的形式进行了深入讨论。     

数字迷宫

你要在这个迷宫中,走到标示着“F”的终点。并且你只能直线前进,图中每个格子里面的数字代表下一步你可以走几格。从左上方的“3”处开始,如图所示,你有两种走法。     

玻色-爱因斯坦凝聚体中的三角涡旋格子

 讨论了玻色-爱因斯坦凝聚体中的三角涡旋格子,从磁光阱里玻色-爱因斯坦凝聚体波函数满足的Gross-Pitaevskii方程求出三角格子的解,并简要解释了相关实验观察结果.     

复合材料雷体的UWB-EMP耦合效应研究

针对高功率微波(High power microwave,HPM)扫雷装置对现代地雷构成的严重威胁,为提高地雷抗电磁毁伤能力,将不锈钢纤维(Stainless steel fibers,SSF)作为聚酰胺树脂的导电填料,研究新型复合屏蔽材料地雷壳体。针对雷体结构和布设状态,采用时域有限差分(Finite difference time domain,FDTD)数值方法,分析该壳体的超宽带电磁脉冲(Ultra-wide band electromagnetic pulse,UWB-EMP)孔缝耦合规律。加工复合材料地雷壳体样品,内置电子引信并连接电引火头,在微波暗室进行峰值功率1 GW的UWB-EMP辐照下的效应实验,壳体放置天线前的距离大于0.5 m时,内部电子引信能正常工作。结果表明:该壳体能有效提高电子引信地雷抗强电磁毁伤等复杂战场电磁环境下的生存能力。     

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.     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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