基于最大流最小割算法的事件检测方案

文中把最大流最小割算法应用于无线传感网络的事件检测中,针对边沿陡峭的事件,设计事件区域检测算法(G-Cut).该算法首先将相邻节点的传感数据转化为权值,形成流网络;利用最大流最小割算法切割流网络,获得事件边界;再根据上传信息隐含的方向,确定事件区域.以野外火灾为例进行仿真实验,结果表明:文中算法事件检测准确度高,节点计算量低;针对多事件区域,在不增加节点计算量和通信量的情况下,仍可保证其检测准确度.     

基于交叠网格模型的WSN抗捕获攻击密钥管理方法

由于无线传感网络节点的存储、计算和通信资源有限,传统的无线传感网络密钥管理算法大多偏重于降低节点的运行能耗或提高连通性,而导致网络的抗捕获性能不足.本文针对该问题,提出基于交叠网格模型的强抗捕获性无线传感网络密钥管理方案.首先在现有网格模型的基础之上,通过在网格间增加中间区域划分,建立一种新的交叠网格部署模型,该区域在...     

有限元分析双体船扭转强度

针对双体船扭转强度问题 ,提出了有限元分析的力学计算模型和计算方法 .按现行规范要求对一艘沿海航区的高速双体客船进行了实算和强度校核 .计算结果表明 ,计算方法是可行的 ,计算模型是合理和高效的     

基于网格的无线传感网传输延迟预测方法研究

针对无线传感器网络传输信道受到介质的多途效应影响而易出现传输时延的问题,提出一种基于网格的无线传感网传输延迟预测方法。构建无线传感网络的信道传输模型,进行无线传感器网络传输信号分析,结合传感器节点的优化部署方法进行节点网格路由设计,根据无线传感器网络信号传输的多径特征进行网格区域部署,实现无线传感网络的信道均衡控制,结合相关性检测方法进行无线传感网传输延迟参量估计,采用最大似然估计方法实现对无线传感网传输延迟的准确估计和预测。仿真结果表明,采用该方法进行无线传感网传输延迟预测的准确性较高,降低了传输延迟失真和误码。     

基于影响函数法的复杂辊系有载辊缝模型优化

精确的板形控制理论对提高板带轧制质量有重要意义,而辊缝的高效预测是板形控制理论的重要内容.针对复杂辊系的辊缝在线计算问题,给出一种高效的计算方法.该方法以在简单辊系中成熟应用的影响函数法为基础,结合有限元法中建立刚度矩阵思想,并通过矩阵迭代方式求解矩阵来预测辊缝.通过对辊间接触压力向量Ψ的前置处理,实现了高效的初值预设,新型预测模型的求解速度与精度进一步提高.将该预测方法与有限元法对比分析,发现该方法计算时间大大少于有限元法,但精度与有限元法相近,最大误差仅为1.6%,满足在线计算时的要求.     

水下无线传感网络仿真工具研究

水下无线传感网络不同于在陆地上基于电磁波的无线传感网络,尤其是对水下无线传感网络的仿真;如何模拟水下或海洋的复杂环境,建立高效逼真的仿真环境尤为重要,该文主要针对现有的水下无线传感网络模拟器进行介绍,讨论各种仿真器的特点。     

磁流体光子晶体微腔的磁场响应特性

提出了基于磁流体光子晶体的微腔,并对其形成过程进行了理论解释,进而研究了该微腔的传感特性,计算了其光透射特性.分析了薄膜厚度分别为6μm和0.94μm时磁流体光子晶体微腔的磁场响应特性.研究结果表明,随着外加磁场增加,这两种结构的光子晶体谐振峰中心波长分别蓝移了4.130μm和0.076μm;磁场响应的最大灵敏度分别为243 nm/m T和3.8 nm/m T.这种基于微腔的传感系统具有易调谐、制备简单,且灵敏度高等优点,为胶体光子晶体在传感领域的应用提供了新的思路.     

液压挖掘机中负荷传感系统的分析与计算

负荷传感系统因其节能、效率高和寿命长的显著优点在现代工程机械中获得了广泛的应用,特别是在液压挖掘机的液压动力控制系统中,往往较多地采用负荷传感系统,以达到节能和高效的目的,以WYL22液压挖掘机的液压系统为例,在对开环负荷传感系统（OLSS）和闭环负荷传感系统（CLSS）进行性能分析的基础上,对OLSS的喷嘴传感器关键尺寸参数提出相应的计算方法。     

基于FBG传感器的三维空间应变监测

目的研究基于光纤布拉格光栅(FBG)传感器的三维空间应变监测方法,实现FBG传感器对测点三维空间应变状态的监测.方法根据空间直角坐标系建立立方体框架,在框架内特定的方向上布设6个FBG应变传感器与1个FBG温度传感器形成三维空间FBG传感体.在所有传感器协同工作下,对测点的三维空间应变与温度进行监测.结果给出了基于FBG传感器的三维空间主应变,最大切应变及任意方向正应变的计算方法,并且根据该计算方法在Lab VIEW平台下开发了三维空间应变监测与分析系统.结论根据本监测方法制作的三维空间FBG传感体可以应用在房屋、桥梁、道路、大坝、雕塑等结构的监测当中.该传感体与相应的解调设备和所研发的应变监测与分析系统构成了完整的三维空间应变监测体系.     

考虑多个子群意见的多要素大群体决策方法

针对存在多个子群的多要素大群体决策问题，提出一种决策分析方法.首先，依据参与决策的个体针对方案构成要素的排序，计算各要素针对各参与个体的borda分值.其次，构建要素针对各子群的平均borda分值向量，再将其归一化后作为针对各子群的虚拟方案.然后，考虑到各子群的评估一致性存在差异，计算各子群的权重.进一步地，计算各虚拟方案与各备选方案之间的贴近度，并将其与各子群权重相集结，得到针对各备选方案的综合贴近度，并据此对备选方案进行排序.最后，通过一个考虑公众意愿的城市公园设计方案选择问题的算例说明了所提出方法的可用性.     

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     

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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