军用车辆常用数据总线性能比较及发展趋势

介绍了军用车辆常用数据总线———C A N总线、1553B总线及M IC总线的体系结构,对其实时性、可靠性、经济性等指标进行了比较,分析了各自的应用场合及发展趋势。结果表明,C A N、1553B和M IC三种总线均具有传输速度快、可靠性高、实时性好等特点;CAN 总线因其技术开放性和较高的性价比,获得了比 MIC和1553B总线更广泛的应用;1553B和M IC总线则在航空、军事等领域应用较多;M IC总线较1553B结构简单,但在实现功能复杂的系统时没有1553B总线灵活。     

星载SpaceWire-1553B总线桥接器设计

为适应卫星通信网络的多总线构架及采用Space Wire总线的发展需求,设计了一种Space Wire-1553B总线桥接器,既是1553B总线RT设备又是Space Wire网络控制器,还实现了两种总线协议的桥接。跨总线的指令时延为16.3μs,且桥接器以0.2 s的频次更新Space Wire网络所有设备的运行状态信息,满足了通信网络的指令响应和遥测更新要求。     

1553B总线与ARINC429总线转换技术的应用

航空武器系统的设计,经常需要将1553B总线与ARINC429总线进行双向数据转换。飞机航电系统把1553B总线作为BC使用,运载悬挂物把1553B总线作为RT使用,任务悬挂物内部使用ARING429总线,两种总线的标准差别较大。为了实现两种总线的转换,本文介绍1553B总线与ARINC429总线转换技术在运载悬挂物中的应用。     

1553B总线和CAN总线信息转换技术中的异步FIFO设计

分析了如何在FPGA中设计一个可靠性较高的异步FIFO实现高速4 Mb/s的1553B总线和1 Mb/s的CAN总线互连转换.介绍了格雷码作为异步FIFO读写指针的方法,并详细给出了降低亚稳态发生概率的措施.该异步FIFO满足系统实时性要求.     

1553B总线信息流设计

论述1553B总线信息流设计在车辆电子综合系统中的应用，分析了1553B总线的原理和信息传输机制，提出信息流设计系统的功能、设计原则、数据结构和算法．系统初步使用结果表明，1553B总线信息流设计在总线消息传播、流量控制、差错控制和网络管理等方面具有良好的控制作用，提高了通信质量．     

基于FPGA的1553B总线测试系统设计

MIL—STD—1553B总线是美国定义的军用串行总线标准,具有完整的、高可靠性总线通信协议,在航空电子、卫星导航、武器系统等领域得到广泛的应用。但是MIL—STD—1553B总线测试繁琐复杂,基于目前市场上的各种1553B总线测试卡进行某些实时性要求高的特殊测试实现比较困难。本文设计了一种基于FPGA实时配置两块BU61580芯片,并与两块BU61580芯片进行实时通信,实现BC、BM/RT与设备进行通信;FPGA通过USB接口与上位机进行通信,最终实现可由上位机软件灵活配置进行1553B总线测试的测试系统。实践证明：通过上位机软件可以完成1553B总线通信原型的快速测试、复杂通信逻辑测试、通信实时性测试等测试过程,是一种行之有效的测试方法。     

1553B总线在嵌入式图形显示控制板中的硬件实现方法

通过对1553B总线的研究,设计出了集成1553B总线的嵌入式图形显示控制板,该图形控制板具有集成度高、图形功能丰富和处理速度快的特点.     

1553B总线系统优化及可靠性设计

介绍了1553B总线消息传输系统,推演了一种1553B总线系统消息传输优化设计的方法并归纳了几种提高总线系统可靠性的方法,运用上述方法能有效提高总线系统的性能.     

基于静态链接库的1553B总线通讯编程方法

机载设备中,1553B总线因其冗余度高,响应速度快的优势而被广泛应用。进行编程时,通过使用链接库,可在不了解详细构造的环境下,仅通过调用顶层函数便可实现对不同厂家接口模块的编程。本文从1553B总线的构造出发,通过比较静态链接库和动态链接库的区别,给出了一种通过调用静态链接库与1553B总线接口模块通讯的编程方法。     

Linux系统中1553B总线内核态驱动开发研究

本文开发了基于Linux系统的1553B总线内核态驱动程序,分析了1553B总线的内核态驱动程序并充分利用Linux系统中的Tasklet等下半部机制开发了相应的中断处理程序,同时对通信协议层进行了大量的优化。最后通过实验对驱动程序的性能进行了测试,并和目前已有的用户态驱动程序的性能进行了比较。测试结果表现良好,大大降低了整个1553B总线通信系统的成本,有望使1553B总线通信系统在工业领域得到普遍应用。     

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