Unified routing protocol based on passive bandwidth measurement in heterogeneous WMNs

The past few years have witnessed a surge of wireless mesh networks (WMNs)‐based applications and heterogeneous WMNs are taking advantage of multiple radio interfaces to improve network performance. Although many routing protocols have been proposed for heterogeneous WMNs, most of them mainly relied on hierarchical or cluster techniques, which result in high routing overhead and performance degradation due to low utilization of wireless links. This is because only gateway nodes are aware of all the network resources. In contrast, a unified routing protocol (e.g., optimal link state routing (OLSR)), which treats the nodes and links equally, can avoid the performance bottleneck incurred by gateway nodes. However, OLSR has to pay the price for unification, that is, OLSR introduces a great amount of routing overhead for broadcasting routing message on every interface. In this paper, we propose unified routing protocol (URP), which is based on passive bandwidth measurement for heterogeneous WMNs. Firstly, we use the available bandwidth as a metric of the unification and propose a low‐cost passive available bandwidth estimation method to calculate expected transmission time that can capture the dynamics of wireless link more accurately. Secondly, based on the estimated available bandwidth, we propose a multipoint relays selection algorithm to achieve higher transmission ability and to help accelerate the routing message diffusion. Finally, instead of broadcasting routing message on all channels, nodes running URP transmit routing message on a set of selected high bandwidth channels. Results from extensive simulations show that URP helps improve the network throughput and to reduce the routing overhead compared with OLSR and hierarchical routing. Copyright © 2016 John Wiley & Sons, Ltd.     

考虑电池寿命和运行控制策略影响的风电场储能容量优化配置

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一种用于多信道无线Mesh网络的信道分配方法

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载重子午线轮胎胎体成型稀线的原因分析及解决措施

分析载重子午线轮胎胎体成型稀线的原因并提出解决措施.分析表明,造成轮胎成型稀线的主要原因是接头机工作不稳定,通过对电动接头机和帘布自动裁刀进行改进、规范接头机工艺参数、制定标准化作业指导书和建立过程监控制度等措施,有效地防止了稀线废次品的产生.     

基于改进遗传算法的继电保护一体化图形 拼接厂站最优布局

继电保护整定计算在电力系统广泛采用分布式整定计算模式,在继电保护整定计算模型拼接中,图形拼接部分存在着接线混乱的问题。深入研究了一体化继电保护图形拼接的特点,结合厂站电压等级,提出了基于改进遗传算法的继电保护一体化图形拼接方法。为了提高图形拼接的效率,采用按电压等级分层寻优的方式确定最优厂站布局。最后通过实际算例验证了该方法的快速性及有效性。     

气/汽-液相分离技术研究进展

从相分离原理的角度出发,分别介绍了惯性力相分离、离心力相分离以及毛细力相分离技术。其中,惯性力相分离技术主要介绍T型管的应用,毛细力相分离技术分别介绍了毛细管、多孔膜以及金属丝网3种主要结构。同时简要评价了各相分离技术的优缺点及发展趋势。     

Investigation of Serine‐Proteinase‐Catalyzed Peptide Splicing in Analogues of Sunflower Trypsin Inhibitor 1 (SFTI‐1)

Serine‐proteinase‐catalyzed peptide splicing was demonstrated in analogues of the trypsin inhibitor SFTI‐1: both single peptides and two‐peptide chains (C‐ and N‐terminal peptide chains linked by a disulfide bridge). In the second series, peptide splicing with catalytic amount of proteinase was observed only when formation of acyl–enzyme intermediate was preceded by hydrolysis of the substrate Lys–Ser peptide bond. Here we demonstrate that with an equimolar amount of the proteinase, splicing occurs in all the two‐peptide‐chain analogues. This conclusion was supported by high resolution crystal structures of selected analogues in complex with trypsin. We showed that the process followed a direct transpeptidation mechanism. Thus, the acyl–enzyme intermediate was formed and was immediately used for a new peptide bond formation; products associated with the hydrolysis of the acyl–enzyme were not observed. The peptide splicing was sequence‐ not structure‐specific.     

抗体重链轻链可变区连接条件的优化

采用重叠延伸PCR(SOE-PCR)法拼接VH、Linker、VL,优化了SOE-PCR中模板量、引物量、退火温度及DNA聚合酶量。确定了优化的连接条件为:50μL反应体系中,SfiI-VH-Linker-232ng,Linker+-VL-NotI 200ng,于64.8℃退火,7个循环后,各加入上下游引物1.5μL(10μmol·L-1),再另加PrimeSTAR HS DNA Polymerase 0.5μL,于62.0℃退火,扩增25个循环。在改进后的连接条件下,可获得高纯度、高丰度的扩增产物,利于抗体库的多样性。     

基于有限元的脉冲激光辐照材料温度场研究

在激光超声检测过程中,为了合理加载脉冲激光的能量,以便获得幅值较大的超声波信号,同时避免脉冲激光造成材料的损伤,需要对脉冲激光辐照材料的温升进行数值计算。依据有限元理论,建立脉冲激光辐照材料的有限元模型,结合导热微分方程,将脉冲激光以热流密度的形式加载于材料表面,分析材料表层受激光辐照时的温度场,讨论有限元热分析时网格尺寸的选取对分析结果的影响。给出了材料表层受脉冲激光辐照时温度场的计算方法和网格尺寸的选择依据,并利用温度场的理论解析结果和应力场分析结果分别验证了温度场有限元计算方法的正确性和有效性。     

一种超宽带线性调频信号源的设计

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