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71.
集中集成的线损综合分析系统及其应用 总被引:2,自引:0,他引:2
介绍了由多个现有信息系统集成的线损综合分析系统的信息结构、组成结构和业务功能.对其应用效果的分析表明,该系统能为全面降低线损,为实现节能增效提供技术保障. 相似文献
72.
根据分布式光纤温度传感器被测信号的特殊性,在常规微弱信号检测的基础上,提出了一种专门的、针对分布式光纤温度传感器系统的微弱信号检测方案,采用软、硬件结合的方案,能够在强噪声下有效地提取微弱信号,以求得尽可能大的信号噪声比,而所需的器件与设备极为通用,相对成本较低,检测整个过程完成的时间也较短,具有较高的实用性。 相似文献
73.
灵活高效的频谱共享技术能够实现频谱资源的最大化利用,有效地缓解了无线频谱紧缺的现状。在一个与TDMA/FDMA蜂窝网络共存的多跳认知无线Mesh网络环境下,基于覆盖式(Underlay)与机会式(Overlay)相结合的频谱共享机制,提出了一种有效的链路层频谱决策与网络层路由的跨层设计方案。仿真结果表明,该方案比基于最小跳数的随机信道选择算法在网络端到端传输性能上有显著的优势。 相似文献
74.
Intrusion detection is prominently important for civil and military applications in wireless sensor networks (WSNs). To date, related works address the problem by assuming a straight‐line intrusion path and a Boolean sensing model. However, a straight‐line intrusion path is often not the case in reality, and the Boolean sensing model cannot resemble a real‐world sensor precisely. Results based on these assumptions are therefore not applicable with desirable accuracy in practice. In view of this, we propose a novel sine‐curve mobility model that can simulate different intrusion paths by adjusting its features (amplitude, frequency, and phase) and can be integrated into the random WSN model for intrusion detection analysis. It can also be applied to different sensor models and makes influencing factors tractable. With the model, we examine the effects of different intrusion paths on the intrusion detection probability in a random WSN, considering both Boolean and realistic Elfes sensing models. Further, we investigate the interplays between network settings and intruder's mobility patterns and identify the benefits and side effects of the model theoretically and experimentally. Simulation outcomes are shown to match well with the theoretical results, validating the modeling, analysis, and conclusions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
75.
浙江省绍兴市本级范围内的有线电视业务投诉受理流程从2007年开始进行重组,引入了客户服务中心的电子政务模式,对重组前后的流程从过程、优化方法的应用以及绩效评估等方面进行了对比。 相似文献
76.
Tsang‐Chi Lee Jui‐Yi Hung Yun Chi Yi‐Ming Cheng Gene‐Hsiang Lee Pi‐Tai Chou Chung‐Chia Chen Chih‐Hao Chang Chung‐Chih Wu 《Advanced functional materials》2009,19(16):2639-2647
A new series of charge neutral Os(II) isoquinolyl triazolate complexes ( 1 – 4 ) with both trans and cis arrangement of phosphine donors are synthesized, and their structural, electrochemical and photophysical properties are established. In sharp contrast to the cis‐arranged complexes 2 – 4 , the trans derivative 1 , which shows a planar arrangement of chromophoric N‐substituted chelates, offers the most effective extended π‐delocalization and hence the lowest excited state energy gap. These complexes exhibit phosphorescence with peak wavelengths ranging from 692–805 nm in degassed CH2Cl2 at room temperature. Near‐infrared (NIR)‐emitting electroluminescent devices employing 6 wt % of 1 (or 4 ) doped in Alq3 host material are successfully fabricated. The devices incorporating 1 as NIR phosphor exhibit fairly intense emission with a peak wavelength at 814 nm. Forward radiant emittance reaches as high as 65.02 µW cm?2, and a peak EQE of ~1.5% with devices employing Alq3, TPBi and/or TAZ as electron‐transporting/exciton‐blocking layers. Upon switching to phosphor 4 , the electroluminescence blue shifts to 718 nm, while the maximum EQE and radiance increase to 2.7% and 93.26 (μW cm?2) respectively. Their performances are optimized upon using TAZ as the electron transporting and exciton‐blocking material. The OLEDs characterized represent the only NIR‐emitting devices fabricated using charge‐neutral and volatile Os(II) phosphors via thermal vacuum deposition. 相似文献
77.
Most of the existing cooperation methods select relay node(s) mainly based on the channel state information, but do not consider
whether the selected relay nodes work or not. If the selected relays are invalidated, the performance of cooperative communication
will deteriorate. To resolve the above problem, this paper investigates cooperative communication in IEEE 802.11 networks,
and proposes a novel Spare Cooperative Method (SCM). SCM chooses a spare cooperation node to enhance the reliability of communication,
and uses an enhanced handshaking mechanism to coordinate the access of source nodes and cooperation nodes to the wireless
channel. The performance of SCM is comprehensively analyzed in terms of outage probability and saturated throughput. The analysis
shows that SCM improves the performance of IEEE 802.11. 相似文献
79.
压水堆核电厂一般采用天然硼来控制反应性。在核电厂实施长循环燃料管理后,寿期初硼浓度较高,增加了水化学控制的压力。本文开展了富集硼酸(EBA)在一回路水化学中的应用可行性及其对相关水质处理系统的影响分析。研究表明一回路采用EBA有助于降低结构材料的腐蚀和堆外辐射场,提高在役核电厂的经济性。 相似文献
80.