基于双优先级队列的异构分布式控制系统容错调度算法

在对分布式控制系统进行分析的基础上,给出了任务模型和处理器模型.为了调度多种实时性的任务,提出了双优先级队列调度算法,用于调度每个处理器上的任务.该算法设置2个优先级队列,其中高优先级队列用于调度实时任务,低优先级队列用于调度非实时任务,高优先级队列中的任务可抢占低优先级队列中的任务.在此基础上,采用版本复制技术使系统具有容错能力,并分析了任务的容错可调度条件.基于此,采用首次适应的启发式任务分配策略,将任务分配到各个处理器上,在确保任务容错可调度的条件下使处理器负载均衡.仿真结果表明所提出的算法是有效的.     

应用于低功耗嵌入式处理器的功耗动态管理策略设计

为了降低嵌入式应用系统的功耗和成本,设计实现了一种应用于低功耗嵌入式处理器的功耗动态管理策略.该功耗动态管理策略包括多工作模式切换、动态频率调节、动态电压调节和快速可变的电压供给单元全集成,在满足功能和性能要求的基础上,根据处理器执行任务的需求变化,切换处理器的工作模式,动态调节工作频率与工作电压,降低功耗;快速可变的电压供给单元也集成于处理器中,支持工作电压的实时快速调节,降低系统成本.基于嵌入式应用系统样机的验证结果表明,应用系统执行不同的进程任务时,功耗均有效下降.在嵌入式应用系统中采用该功耗动态管理策略,能够有效降低系统的功耗与成本.     

嵌入式实时系统周期任务能耗感知调度

在电池供电的嵌入式实时系统中,针对实时周期任务集在一个可变电压处理器上的能耗感知调度问题,在改进的人工鱼群算法(improved artificial fish school algorithm,IAFSA)基础上,提出了一种离线的能耗感知调度算法,该算法通过构造人工鱼的行为约束自然地满足时限和能耗约束,最大化系统总奖赏值。与贪婪算法相比,该算法提高系统的总奖赏值约47%。且随着电池能量的减少,系统能耗利用效率逐渐增大,说明该算法具有良好的能耗感知特性。     

有通信冲突的异构系统上的任务调度

在新的系统模型上，提出了一个任务调度算法．该系统模型考虑了通信冲突，即在任何时刻，一个处理器只能接收一条消息，发送一条消息．新的算法包括异构系统中任务优先级的高效排序和基于任务复制的处理器分配两部分．随机产生的任务图和一个具体应用的任务图进行调度试验的结果表明，该算法比已有调度算法的性能有了显著的提高．     

一种新的静态优先级在线节能调度算法

合理运用动态电压调整技术可有效降低嵌入式实时系统能耗.针对静态优先级实时调度,提出了一种能够有效分析松弛时间并尽可能平衡分配松弛时间的在线节能调度算法TPSRM.设计了一种两段式频率执行策略来改变任务执行时间的分配,能充分在线分析各种形式的松弛时间.通过尽可能合理降低高优先级任务的处理器执行频率来实现有效的在线频率调整.实验结果表明TPSRM算法可实现较好的节能效果.     

Windows NT操作系统的优先级调度及一种改进方法

首先简要介绍ＷｉｎｄｏｗｓＮＴ操作系统以优先级为基础来安排所有活动的机制,并对其优缺点进行分析．然后针对其局限性,引入一种新的处理器调度方法———处理器继承调度．在此模型中,某些基本线程可作为其它线程的调度者．很多不同的调度策略均可在此框架下得以实现,并且可共存．最后,对于ＷｉｎｄｏｗｓＮＴ操作系统采用此框架的可行性作一定性的讨论,此调度方法的采用将会大大提高系统的灵活性．     

一种实时多任务管理机制

研究一种实时多任务管理机制．讨论了ＲＭＤＯＳ系统结构与支撑环境、多任务控制流程和调度问题．该管理机制实现了可变优先级加时间片轮转的调度策略和网络任务的实时响应．它作为多任务操作系统的核心，成功地支持了分布式操作系统ＨＺＤＯＳ的实现和分布式并行任务分配，支持了分布式系统故障恢复与系统重构     

一种基于模糊逻辑优先级的雷达任务自适应调度算法

为适应目标环境变化情况,提出了一种基于模糊逻辑优先级的雷达任务自适应调度算法.该方法基于目标运动状态和属性通过模糊逻辑推理动态确定任务的优先级,并结合时间窗的特点采用一步回溯方法调整发生冲突的任务,保证更多高优先级的任务在其期望的时间内被调度.仿真结果表明,该调度算法在保证调度率的前提下降低了任务的调度代价.     

基于可变队列长度固定优先级控制策略的话音 Ⅰ.数据单一信道复用系统性能模型

将可变队列长度固定优先级控制策略用于话音/数据单一信道复用系统,推导出了在此环境下的系统性能分析模型,该模型为话音/数据单一信道复用系统在可变队列长度固定优先级策略控制下的性能分析,以及多种控制策略的量化比较提供了方便有效的手段。     

满足吞吐约束与资源节约的任务流调度方法

根据实时信号处理应用中嵌入式计算硬件的资源受限特点,提出一种新的适合计算任务流的实时任务调度算法,以满足吞吐率为调度约束条件、以最小化流水线时延为调度目标并兼顾资源节约原则.算法为两层结构,首先采用任务插入策略得到满足吞吐率约束的中间结果;再通过基于任务复制的优化调度,分析了影响调度长度的关键任务并按照所定义的优先级构造关键边的决策树以确定需复制的关键父任务,充分利用了处理器的空闲时间片以减少时延.另外还设计了检测任务复制后出现的冗余处理器的方法.通过随机任务图仿真分析,说明该算法能以较小的处理器使用量获得满足吞吐率约束的调度结果.     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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     

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