带移动中继的WSN移动路由算法

为了延长带有sink节点的无线传感器网络生存周期,避免因局部突发事件造成网络过早失效,提出一种带移动中继的WSN移动路由算法。该算法基于网格思想,根据节点的剩余能量以及离簇重心坐标距离的加权和来选举簇头,通过可控移动策略调度sink节点,接收簇头所收集的数据,节省网络能耗。另外,引入能量不受限的中继节点,调度该节点服务于信息传输大的区域,延长网络生存周期。最后,从网络总能耗、节点存活数及汇聚节点接收的数据量这3个方面,将该算法与不带中继节点的WSN移动路由算法(MSEERP)进行仿真分析对比,分析结果表明该算法优于MSEERP算法。     

一种基于安全移动代理的路由算法设计

移动代理通过遍历网络收集信息,由于网络的开放性,代理及其内部数据的安全受到巨大威胁.提出了一种基于安全移动代理的路由算法的设计思想,使用概率值来构造路由表,通过移动代理在网络节点间地迁移,来发现网络状态,更新节点路由表.同时在网络节点处建立信任表,定期生成TestDataAgent(测试代理)在虚拟空间中运行,并对其属性和关键数据进行检测以保证网络节点的可靠性,实现代理在网络中的安全.还用Grasshopper移动代理开发平台构造了一个简单网络模型,对此算法进行了验证.     

传感器网络中一种基于簇的路由算法的研究

为了降低无线传感器网络中节点的能量消耗,提高网络生存期,提出了一种基于簇的路由算法.该算法首先采用K均值动态聚类算法将网络分簇,靠近Sink节点处具有更多的簇;其次利用数据汇聚路由算法寻找从簇头节点到Sink节点的路由;最后由当前簇头根据节点剩余能量及邻居节点的位置重新选择下一轮的簇头,并由新簇头形成簇间路由.仿真计算证明该算法是合理有效的,达到簇内节点能量均衡消耗的目的,同传统分簇算法相比,具有更长的网络生存期和更低的通信能耗.     

移动自组织网络中一种能量有效的跨层协议

提出了一种移动自组织网络中能量有效的跨层协议,将网络层的能量感知路由协议与MAC层的功率控制协议相结合,以提高节点的能量利用效率.在路由协议中根据节点剩余能量决定节点接入路由的延迟时间,从而使剩余能量较多的节点能够更快地接入路由,以使网络中的能量消耗更公平.在MAC层中实现功率控制,减少节点的实际能量消耗.仿真结果表明,在移动自组织网络中,该能量有效的跨层协议不但能延长网络的生存时间,减少端到端延迟,而且可以提高网络吞吐率.     

一种基于代理和环形路由的传感器网络覆盖空洞修复策略

提出一种基于代理和环形路由的传感器网络覆盖空洞修复策略。此策略的核心在于:每一个休眠节点选取距离自己最近的工作节点作为代理节点,以代理节点与网络几何中心的连线方向扩散其位置信息,形成纵穿网络的存储代理信息的扩散路径;当网络中工作节点濒临死亡时,从代理节点开始以网络几何中心为圆心进行绕环路由,定位替换节点;经过仔细规划对信息路由的剪枝规则,降低节点的存储信息量。通过理论与仿真实验对网络能耗、节点移动距离和节点存储容量等多个方面对修复算法进行分析、评价与实验。研究结果表明:本文提出的策略有利于降低网络能耗,提高节点存储容量。     

基于上下文认知的高能效路由算法

针对由智能移动通信设备组成的、支持网络富媒体应用的无线Ad hoc网络环境,提出了一种基于上下文认知的高能效路由算法.该算法使用上下文认知自学习方法监测设备运行过程中的上下文信息,计算节点上各类应用对应的能量效用值,然后综合利用节点上与应用相关的能量效用、剩余能量和信号强度等上下文信息自适应地调整路由,为资源受限的移动节点节约能量.仿真结果表明,与一些经典路由算法相比,文中路由算法能有效地提高网络的能量使用效率和网络生存时间,减少网络的时延开销.     

移动ad hoc网络多参数加权分簇算法

网络分簇支持资源空间复用,能增大系统容量;簇头构成虚拟骨干网,能降低路由开销;但簇生成和维护涉及信息交互,会增加通信开销,良好的分簇算法是维持簇稳定的关键。针对移动ad hoc网络,提出一种多参数加权分簇算法。该算法综合考虑节点剩余能量、邻居节点数和节点移动性,分别针对随机步行移动网络和参考点群组移动网络设计不同的节点稳定性参数,在随机步行移动网络中利用剩余能量参数、邻居节点参数和相对稳定性参数加权构成稳定性参数,而在参考点群组移动网络中采用剩余能量参数、邻居节点参数和移动相关性参数加权构成稳定性参数。仿     

WSN中安全且能量有效的移动代理路由协议

针对无线传感器网络(WSN)中移动代理路由协议的安全和能耗问题,提出一种动态的分布式解决方案,称为安全且能量有效的移动代理路由(SEMAR)协议.将WSN构建成环形和楔形结构,并提出一种信任评估模型,代理根据节点的能量和信任值动态建立路由,使其能够识别并绕过恶意节点,同时使用克隆机制来完成每个扇区的数据聚集任务,减少代理负载,降低能源消耗.与现有代理路由协议相比,SEMAR有效提高了代理的往返成功率,降低了整体响应时间和能源消耗.     

基于最佳位置点的移动代理路由算法

针对多移动代理访问数据源节点数增加而出现的传感器节点能量负载不均衡和通信时延等问题。采用基于改进粒子群算法为移动代理规划路径,在网络进行六边形划分的基础上,找到所有可能成为移动代理收集数据的最佳位置点以及最合理的移动代理数,结合网络的能量消耗、通信延时和移动代理负载均衡为目标函数,寻找最优的移动代理移动路径。实验结果表明,该方法在缩短移动代理路径长度和降低通信时延的同时可以有效地均衡网络能耗,达到延长网络寿命的目的。     

基于可调发射功率的无线传感器能量空洞避免算法

基于无线传感器数据收集网络的多对一收集特征,部分节点因为过早耗尽自身能量而导致网络原有覆盖区域缺失或者数据无法送达Sink节点,从而形成能量空洞现象.针对这一问题,提出一种避免能量空洞的算法ATPAEH(adjusting transmission power to avoid energy-hole).首先,根据网络中所有节点的剩余能量信息将节点分为门限节点和充裕节点两个集合.然后,对于门限节点集合中的节点形成最短路径树以多跳的方式将数据传送到Sink节点.而充裕节点集合中的节点根据该节点与Sink的距离调节其自身的发射功率,直接将数据传送到Sink节点.最后,通过与MILD算法的对比实验表...     

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.     

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.     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.