层次化的片上网络设计方法

半导体技术的发展以及系统芯片应用复杂度的不断增长,使得片上互连结构的吞吐量、功耗、信号完整性、延迟以及时钟同步等问题更加复杂,出现了以片上网络为核心的通信结构。由于系统芯片结构和片上通信的固有特性,从提高通信性能和降低硬件开销的角度进行层次化片上网络的设计对系统芯片的发展具有重要意义。本文提出了层次化的片上网络设计方法,根据实现工艺和应用需求,进行层次划分,产生若干个IP子集(将这个子集称为"簇"),按照簇间的通信需求进行片上网络的设计。实验表明,采用层次化的片上网络设计方法,能够有效提高系统性能,降低硬件实现的开销,同时满足一定的服务质量要求。     

层次化的片上网络设计方法

半导体技术的发展以及系统芯片应用复杂度的不断增长,使得片上互连结构的吞吐量、功耗、信号完整性、延迟以及时钟同步等问题更加复杂,出现了以片上网络为核心的通信结构.由于系统芯片结构和片上通信的固有特性,从提高通信性能和降低硬件开销的角度进行层次化片上网络的设计对系统芯片的发展具有重要意义.本文提出了层次化的片上网络设计方法,根据实现工艺和应用需求,进行层次划分,产生若干个IP子集(将这个子集称为"簇"),按照簇间的通信需求进行片上网络的设计.实验表明,采用层次化的片上网络设计方法,能够有效提高系统性能,降低硬件实现的开销,同时满足一定的服务质量要求.     

基于片上网络资源节点的通信协议研究

为了克服总线架构的SoC设计方法不能有效解决片内多处理器系统的通信问题,应用NoC(片上网络)将计算机网络技术移植到芯片设计中,提出了一种适宜于片上网络资源节点通信的单向总线架构。借鉴以太网数据帧格式定义了数据传输协议,利用软核处理器MicroBlazer作为主资源节点,Flash控制器和RS232串口控制器作为从资源节点,在Xilinx FPGA开发板上验证了单向总线架构的可行性。该总线易于扩展资源节点,可实现主资源节点对两个及两个以上从资源节点的同时访问。实验证明,本设计单向总线结构简单,资源节点易于扩展,提高数据传输速率,增强系统性能。     

层次化架构嵌入式多核处理器原型设计及其编程研究

VLSI技术进步和应用驱动使多核技术成为主流的微处理器设计技术。多核处理器作为一种时空域器件,应把超级计算机作为多核处理器的设计参考系,其主流架构将最终收敛到"小核、大阵列、层次化"上。文章利用Xilinx Virtex5-330TFPGA器件,设计实现了一款集成16个处理核的具备层次化架构特征的嵌入式多核处理器原型芯片,工作频率为90 MHz。多核处理器利用层次化的体系架构、灵活的片上互连、多种同步机制以及合理的并行程序模型,成功加载了实时视频淡入淡出(fade-in-fade-out)混叠应用(320×240,30帧/s)。基于该多核处理器架构,研究比较了粗粒度和细粒度2种并行编程模型。细粒度模型的多核同步操作稍复杂,但很好地掩盖了应用的串行操作时间,对视频淡入淡出混叠应用的加速比可达6.97。     

采用数据驱动机制的多核处理器

摘要：
针对当前工艺条件下多核处理器存在程序并行性不足的问题,设计了一种采用数据驱动机制、支持函数语言风格编程的多核处理器,包括通用处理器核、数据驱动模块和片内路由器.其中：通用处理器核用于执行常规程序;数据驱动模块用于检测数据的完备性;片内路由器则可提供处理器核之间及簇之间的通信.实验结果表明,所设计的多核处理器能够支持C语言“函数式语言”风格的编程模板.每个C代码段执行纯函数的操作,消除了函数间的共享变量,使得并行编程的复杂度有所降低.同时,所采用的数据驱动机制没有执行顺序的严格限制,充分挖掘了算法潜在的并行性.经测试,数据驱动多核处理器的加速比随着计算资源的增加而增大,从而验证了数据流计算机的加速倍数随处理器数目增加而线性增长的结论.
关键词：
数据驱动; 并行编程模型; 数据流机; 多核处理器
中图分类号： TP 338
文献标志码： A     

三维众核片上处理器存储架构研究

三维众核片上处理器的研究近年来逐渐引起了学术界的广泛关注.三维集成电路技术可以支持将不同工艺的存储器层集成到一颗芯片上,三维众核片上处理器可以集成更大的片上缓存以及主存储器.研究三维众核片上处理器存储架构,探索了集成SRAM L2cache层,DRAM主存储器层等,对三维众核片上处理器性能的影响.从仿真结果可知,相比集成1层L2cache,集成2层L2cache的三维众核片上处理器性能最大提高了55%,平均提高34%.将DRAM主存储器集成到片上最大可以提高三维众核片上处理器80%的系统性能,平均改善34.2%.     

基于ZigBee技术的无线智能抢答器设计

针对市场上有线抢答器节点安装困难,系统设计安装完成后扩充不便,而无线抢答器扩充节点数目有限,价格过高的问题,利用CC2430处理器和ZigBee技术设计出一个能够双工通信,自动检测、自动恢复、自动语音播报的无线智能抢答器系统。本系统具有成本低、节点扩充容易,经实验测试,性能稳定,能够满足各种抢答竞赛需求。     

WSN虚拟MIMO的非均匀多簇策略研究

在WSN提出一种非均匀多簇协作虚拟MIMO策略.以节点剩余能量、协作节点间距和节点至目的节点间距为参考依据,结合梯度搜索算法选取协作节点,以构建非均匀多簇.簇内节点通过空间分集方式协作通信,簇间通过空间复用方式并行传输,力求分集增益最大化.分析和仿真研究表明:该非均匀多簇协作策略在系统能耗和信道容量方面均有理想性能.     

基于5G通信的多节点无线传感器网络路由算法研究

提出了基于5G通信的多节点无线传感器网络路由算法.通过簇头节点在网格中心的位置以及簇内节点的能量耗损情况,计算5G通信内部产生移动汇聚节点所需的能量,得到无线传感器网格划分的最佳数量.根据网络节点发送过程以及5G通信内部节点数据聚集能力受限状况,计算出最优簇头数目,得出网络分簇结果.选择合适的访问路径,更新多条路径选择策略,增强最优路径内的信息量.实验结果表明,所提算法能有效增加网络密度适应性,降低了数据传输延迟.     

应用Hill-Marty推论对异构多核处理器设计的分析

利用Hill-Marty的多核处理器加速比的推论(芯片中用于共享缓存、互连网络和内存控制器等片上资源不考虑在内),在异构多核处理器中的强内核和弱内核分别与同构多核处理器中的内核性能相同的情况下,计算得出使得异构多核处理器比同构多核处理器性能更优的等价基本核的结构分配方式,从而提出了最优的异构多核处理器核结构配比的设计方案。     

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