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31.
波分复用是增大通信容量,提高线路利用率的常用技术.本文提出了一种用于波分复用系统的ATM光交换模型.该结构利用波分复用的特点,采用内部多通道互连方式,使其具有易于实现、结构简单、对内部缓存要求较低等优点.并对该模型进行了性能分析,得出了结论. 相似文献
32.
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
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提出了在波分复用光纤通信系统中,考虑光纤色散“走离”时受激喇曼散射(SRS)信道的新模型,给出了计算中距离步长的选取公式。根据该模型,数值计算了各信道在随机数字序列调制下和在受激喇曼散射(SRS)非线性效应作用下经过有色散“走离”的波分复用光纤系统的传输功率。得出光纤色散会降低SRS效应引起的输出功率波动的结论,画出了在SRS效应作用下输出功率标准差随色散系数变化的曲线,并对产生该现象的机理进行了定性分析。该模型适合于任意光纤色散、任意输入功率和任意信道数目。 相似文献
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OFDM with mixed-numerologies enhances the system flexibility effectively to meet the demands of diversified application scenarios. However, the coexistence of waveforms with different numerologies leads to serious inter-numerology interference (INI), and the corresponding relationship between the number of guard subcarriers and the power of INI needs to be considered for scheduling subcarriers. In this paper, we propose a multi-scale mapping (MSM) and INI cancellation (MSM-INIC) algorithm as well as the corresponding de-MSM algorithm for mixed-numerologies OFDM system. Based on the proposed algorithms, we provide a novel transceiver in the scenario of multi-path fading channel, in which subcarrier scheduling does not need to consider whether the guard band is allocated. In the proposed transmitter, an additional MSM-INIC module is employed to pre-compensate signal distortion for downlink, and in the receiver, a de-MSM module is applied to de-map the received signals for recovering the original numerologies. Furthermore, we reveal the inherent property of the mapped signals, and propose a low computational complexity de-MSM algorithm accordingly. Simulation results verify the superiority of the proposed transceiver in BER performance as well as spectrum efficiency even without any guard band. 相似文献
38.
Shu Li Qin Hao John Gounarides Y. Karen Wang 《Journal of mass spectrometry : JMS》2012,47(8):1074-1082
The applicability of liquid chromatography–mass spectrometry (LC/MS) is often limited by throughput. The sharing of a mass spectrometer with multiple LCs significantly improves throughput; however, the reported systems have not been designed to fully utilize the MS duty cycle, and as a result to achieve maximum throughput. To fully utilize the mass spectrometer, the number of LC units that a MS will need to recruit is application dependent and could be significantly larger than the current commercial or published implementations. For the example of a single analyte, the number may approach the peak capacity to a first degree approximation. Here, the construction of a MS system that flexibly recruits any number of LC units demanded by the application is discussed, followed by the method to port a previously developed LC/MS method to the system to fully utilize a mass spectrometer. To demonstrate the performance and operation, a prototypical MS system of eight LC units was constructed. When 1‐min chromatographic separations were performed in parallel on the eight LCs of the system, the average LC/MS analysis time per sample was 10.5 s when applied to the analysis of samples in 384‐well plate format. This system has been successfully used to conduct large‐volume biochemical assays with the analysis of a variety of molecular entities in support of drug discovery efforts. Allowing the recruitment of the number of LC units appropriate for a given application, this system has the potential to be a plug‐and‐play system to fully utilize a mass spectrometer. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
39.
Hancheng Zheng Ruiyang Tao Jingyi Zhang Jiashuo Zhang Shouyu Wang Zihao Yang Qiannan Xu Yuzhen Gao Suhua Zhang Chengtao Li 《Electrophoresis》2019,40(20):2644-2654
Human identification and paternity testing are usually based on the study of STRs depending on their particular characteristics in the forensic investigation. In this paper, we developed a sensitive genotyping system, SiFaSTR? 23‐plex, which is able to characterize 18 expanded Combined DNA Index System STRs (D3S1358, D5S818, D2S1338, TPOX, CSF1PO, TH01, vWA, D7S820, D21S11, D10S1248, D8S1179, D1S1656, D18S51, D12S391, D19S433, D16S539, D13S317, and FGA), three highly polymorphic STRs among Chinese people (Penta D, Penta E, and D6S1043), one Y‐chromosome Indel and amelogenin using a multiplex PCR; the PCR amplified products were analyzed using the Applied Biosystems 3500 Genetic Analyzer. Full genotyping profiles were obtained using only 31.25 pg of control DNA; various case‐type specimens, as well as ten‐year‐old samples were also successfully genotyped. Additionally, in the validation studies, this multiplex was demonstrated to be human‐specific and compatible with the interference of multiple PCR inhibitors. The system also enabled the detection of mixtures, and complete profiles could be obtained at the mixed ratios of 1:1, 1:3, and 3:1. The development and validation study here illustrated that the SiFaSTR? 23‐plex system is accurate, powerful, and more sensitive than many other systems. What's more, the population data in our study not only illustrated that this 23‐plex typing system was straightforward and efficient but also expanded the Chinese STR database, which could facilitate the appropriate application of the 23 genetic markers in forensic genetics, especially in the Chinese population. 相似文献
40.
瓦斯爆炸事故频繁发生,对瓦斯浓度进行准确、实时检测和预警是治理瓦斯危害的有效手段。实验研究了基于气体光谱吸收原理,采用1.65 μm波长的近红外可调谐DFB激光器,利用激光器的模式跃变特性设计了差分吸收式的双波长单光路光纤传感网络。使用光开关并结合空分复用技术复用了16个瓦斯传感器,传感气室部分研究了防煤尘等关键技术。经PCI数据采集卡采集各路信号后,利用虚拟仪器对各路信息进行分析并显示。研究表明,在不采用数字锁相放大器,且气体吸收光程只有10 cm的条件下,探测灵敏度达到了0.05%,长时间的精确度和稳定性均可满足实际要求,各传感器切换响应时间小于1 s。该网络只要更换激光器就可对其他气体进行实时检测。 相似文献