蚁群分区算法在QoS单播路由中的应用研究

随着网络技术的高速发展,新型的多媒体业务应运而生,对网络服务质量(QoS)的要求也更高,如何解决多个约束QoS路由问题,成为新关注的热点,在解决这一问题时,路由算法的选择又是其中的一个核心问题,并且带宽、延时、访问花费是决定选择路径的关键因素.论文针对这一状况构建了带有QoS参数的网络模型,并用基于蚁群算法的邻域分区优化算法对QoS单播路由选择进行仿真实验,该方法改善了蚁群算法在求解大规模网络路由选择的算法复杂度和搜索最优路径的时间.     

基于蚁群算法的Qo S路由模型的设计与优化

为了提升网络数据传输中路由性能,采用蚁群算法解决网络路由出现的问题。首先介绍了蚁群算法的原理与模型,然后根据实际应用的QoS路由具体问题,建立QoS路由模型,设计基于ACO的Qo S路由算法。通过仿真实验,对参数进行优化分析,验证了蚁群算法在网络路由中的应用效果,证明这种方法能够提高网络数据传输中路由的性能。     

基于BOA的受限延时QoS路由算法

无线ad hoc网络中受限延时的QoS路由问题是NP-complete问题,针对其特点,将贝叶斯优化算法引入其中,用贝叶斯网络对QoS参数进行模拟、采样和优化.实验结果表明,贝叶斯优化算法对于受限延时的QoS路由问题有着很好的解决能力,同时与其他算法比较,能够搜索到较低代价的路由,满足QoS路由要求.     

一种分布式多路径多约束QoS路由算法

提出了一种以路径剩余带宽为度量标准的分布式多路径多约束QoS路由算法DMPM-CA,该算法能够在源结点和目的结点之间找到多条满足要求的路由路径,并从中选择出有利于网络负载均衡的路由路径。该算法的时间复杂度为O((d 1)L)。     

基于多媒体业务的Ad Hoc网络QoS路由算法

当前Ad Hoc网络QoS路由算法难以满足传输中对多个目标的同时要求.以多媒体 实时业务中有严格限制的时延作为约束条件,把路由费用和数据丢失率作为QoS目标建立了QoS路由选择的多目标整数优化模型,并给出了模型的算法.实例表明了算法的可行性.     

QoS度量帕雷托并行路由快速预计算方法

针对多重链QoS路由问题,在给出Q0s度量的串行寻优算法的基础上,给出一种QoS度量帕雷托并行路由快速预计算方法,此方法为q个Qos度量分配q个处理器,并行计算出满足路由请求约束可行路径的帕雷托子集,在帕雷托子集中综合选择合适的转发路由.实验结果显示该方法能够较好地进行路径寻优,并且算法的复杂度较低,可用于解决有限节点网络的复杂QOS路由问题.     

基于移动Agent的双层卫星网QoS路由算法

结合移动Agent技术提出了一种新的基于双层卫星网络的分布式分层QoS路由算法.该算法利用移动A-gent自主地收集卫星网QoS信息,并动态地更新和维护路由表,同时采用分布式的概率路由选择策略解决了卫星网路由动态变化的问题,具有低复杂度和可扩展的特点.在NS2仿真软件下模拟了该QoS路由算法的性能.结果表明,该算法能较好地避免链路拥塞,同时具有较低的呼叫阻塞率.     

Ad Hoc网络中基于模拟退火-蚁群算法的QoS路由发现方法

针对Ad Hoc网络的动态网络环境和链路、节点性能限制等不利因素，提出了一种新的QoS路由发现方法——SAANT．该方法利用蚁群算法增加了发现可用QoS路由的概率，利用基于概率的路由转发策略来减少洪泛造成的网络开销，从而强化所提算法的全局搜索能力和自适应性，减小了洪泛对Ad Hoc网络性能的影响．所提方法还利用模拟退火算法调整路由发现算法的搜索方向，以弥补蚂蚁算法收敛速度上的弱点，减少了搜索过程中的停滞现象．在包投递成功率、平均包延迟和吞吐量等方面，通过仿真实验对SAANT、仅基于蚁群算法的QoS路由算法和传统的按需路由算法的方法进行了性能比较，结果表明，在Ad Hoc网络环境下，SAANT的收敛速度、移动性能和网络负载性能均表现出更好的适应性．     

基于SDN的QoS测量与路由规划系统设计与实现

采用OpenFlow技术,设计并实现了一套基于软件定义网络的QoS测量与路由规划系统.利用控制器与OpenFlow交换机之间的消息交互,实现SDN中链路时延、负载和丢包率的测量功能.针对QoS路由中存在的"多指标约束限制"问题,根据本文考虑的QoS指标(链路时延、负载和丢包率),改进并实现了一种自适应多指标限制路由算法.实验结果表明:该系统在准确测量链路QoS指标的同时,可以根据测量结果切换符合条件的路由路径,满足系统设计需求.     

基于服务质量的链路不相交路由算法

针对网络可靠性问题,提出了一种基于链路保护机制的QoS路由算法,该算法首先在图论的基础上得到任意两点间的所有路由,再过滤链路条件使其满足QoS约束,由此求出结点对间的两条链路不相交的最短相似路由,对大数据流复用及高实时性网络都起到较好的优化作用.     

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.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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