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91.
介绍了一种基于时分复用光纤传感技术的准分布折射率传感器。通过测量光纤端面的菲涅耳反射信号的强度,实现对待测溶液折射率的分布检测。在多个测量点之间采用不同长度的延迟光纤,利用不同传感位置处的菲涅耳反射信号回到测量端的时间差来实现距离可分辨的多点测量。实验结果表明该传感器的测量距离达16 km,测得折射率范围为1.3486~1.4525,对应的灵敏度范围为38.785~305.430 dB/RIU(RIU为折射率单元)。 相似文献
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We have previously reported a novel approach to implementing multiplex enzyme-linked immunosorbent assay (ELISA) in connected microchannels by exploiting the slow diffusion of the enzyme reaction product across the different assay segments. This work builds on that report by implementing the noted assay in segments arranged along the circumference of a circular channel layout to reduce the footprint size and sample volume requirement. Using the current design, a 5-plex cytokine ELISA was demonstrated in a 1.5 × 1.5-cm region, which corresponded to a reduction in the footprint area by about a factor of 3 compared to that reported in our previous study. Additionally, the selective coating of our assay segments with the target molecules was realized in this work using electroosmosis instead of hydrodynamic flow as was the case in the previous report. This aspect of our experimental design is particularly significant as it permits the use of cross-sectional channel dimensions significantly shorter than those employed in the current work. Moreover, the use of an electric field for coating purposes enables the integration of functionalities such as electrokinetic preconcentration of analyte molecules during the sample incubation period that can further enhance the capabilities of our assay method. 相似文献
96.
In this paper we study translucent optical networks as an alternative to fully transparent and fully opaque optical networks.
In the former networks, a technique called sparse placement is used to overcome the lightpath blocking caused by the signal
quality degradation, using much less regenerators, which must strategically be placed, in contrast to a fully opaque network.
In this paper we propose a sparse placement algorithm based on two requirements. The first one is signal regeneration necessary
to re-amplify, reshape, and retime the optical signals after some predefined transparent distance in order to successfully
receive the signals at the destination node. The other is load balance of the traffic in the network aimed at efficient usage
of the network capacity resources. We apply a distributed Dijkstra routing algorithm which dynamically changes weights of
links during the process of locating regeneration capable nodes. We compare the performance of the proposed algorithm with
commonly used sparse placement algorithms through simulation experiments. The benefits are such that load balancing of the
network traffic is fully utilized, and with technological development it will be sufficient to equip up to 30% of nodes in
the network with electronic regenerations in order to have the same performance as in an opaque network.
相似文献
Jovan RadunovićEmail: |
97.
为代替传统繁杂的汽车线束,汽车CAN总线应运而生。以CAN总线为基础,结合51系列单片机技术,研究开发了汽车前照灯的CAN总线多路传输系统。按照整体结构进行了CAN总线传输节点的软件设计,设计出并口CAN适配卡,通过编写动态链接库(DLL),向上层应用软件提供读/写函数接口,实现了上位机与下位机的通信。该设计使得传统线束大大简化,可靠性得到了极大提高,有效节约了线束安装空间。 相似文献
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随着国民经济的日益增长和信息化技术的迅速发展,CATV网被时代赋予另一层全新的产业发展理念.传统的有线电视HFC网正从单向、单业务化向着双向化、数字化、网络化、宽带化方向发展,并逐渐演变为一个综合的交互式业务信息传输平台,为此,建设一个高质量的有线电视传输网络是今后网络实现双向化和宽带化的前提. 相似文献
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