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991.
ZHANG Qi-zhi LIAO Jian-xin ZHU Xiao-min State Key Laboratory of Networking Switching Beijing University of Posts Telecommunications Beijing P.R. China 《中国邮电高校学报(英文版)》2005,12(2)
1IntroductionIntelligent network,an affiliated network over com-munication network,is introduced for the quick provi-sion of newservices[1 ~2].In the structure of intelligentnetwork,a Service Control Point(SCP) serves a lot ofService Switch Point(SSPs)[3 ~4].It is a veryi mportanttopic that howto guarantee the Qos of SCP (e .g.thenumber of successfully processed calls per unit ti me)whenthe network becomes overloadedinthis centralizednetwork structure . There were many studies about the… 相似文献
992.
LUO Qiang-qiang ZHU Zhi-xiang HUANG Ting-xueXi''''an Institute of Posts & Telecommsunication Xi''''an China 《中国邮电高校学报(英文版)》2005,12(3)
1 Motivation Nowadays , the QoS provided by the wideband IPnetwork starts at an edge-router and ends at anotheredge-router .Therefore ,the trunk QoSisfinished,suchas RSVP[1]and DiffServ[2].In order to complete theend-to-end QoS,the mechanism of entrance QoS (thebandwidth controller) is introduced. As Fig.1 shows ,if the bandwidth controller circledby the dashed frame is not used,the Ethernet is con-nected with the router directly through 100 Mbit/sbandwidth. Then this router is connect… 相似文献
993.
994.
995.
针对光纤光栅工程化应用性能不佳的问题,提出将高强度光纤光栅与碳纤维材料复合,介绍了复合样品的结构形式,分析了应变传递过程,然后对其应变传感特性和疲劳性能进行了实验研究。结果表明:复合样品能够达到较高的应变传递效率,具有良好的应变传感特性;疲劳实验中复合样品保持正常工作,波长变化曲线的幅度稳定;疲劳实验前后复合样品的应变传感特性基本不变,应变灵敏度系数分别为1.12和1.17pm/με,应变响应曲线的线性度均高于0.999,重复性分别为0.623%和0.397%。 相似文献
996.
Michael Angell Guanzhou Zhu Meng‐Chang Lin Youmin Rong Hongjie Dai 《Advanced functional materials》2020,30(4)
The ionic liquid analog, formed through the mixture of urea and AlCl3, has previously shown to serve as a low‐cost electrolyte for an aluminum‐graphite battery, while maintaining good performance and achieving high Coulombic efficiency. Undesirable are the relatively high viscosity and low conductivity of this electrolyte, when compared to chloroaluminate ionic liquids with organic cations. In this work, the fundamental changes to the electrolyte resulting from using derivatives of urea (N‐methyl urea and N‐ethyl urea), again mixed with AlCl3, are examined. These electrolytes are shown to have significantly lower viscosities (η = 45, 67, and 133 cP when using N‐ethyl urea, N‐methyl urea, and urea, respectively, at 25 °C). The associated batteries exhibit higher intrinsic discharge voltages (2.04 and 2.08 V for N‐methyl urea and N‐ethyl urea electrolytes, respectively, vs 1.95 V for urea system@100 mA g?1 specific current for ≈5 mg cm?2 loading), due to changes in concentrations of ionic species. Aluminum deposition is directly observed to primarily occur through reduction of Al2Cl7? when AlCl3 is present in excess, in contrast to previously suggested cationic Al‐containing species, via operando Raman spectroscopy performed during cyclic voltammetry. 相似文献
997.
Hao Wu Lu Zhang Jinfan Yang Ruonan Bo Hongxu Du Kai Lin Dalin Zhang Mythili Ramachandran Yingbin Shen Yangxi Xu Xiangdong Xue Zhao Ma Aaron Raymond Lindstrom Randy Carney Tzu‐Yin Lin Yuanpei Li 《Advanced functional materials》2020,30(15)
Real‐time tracking of the dynamics change of self‐assembled nanostructures in physiological environments is crucial to improving their delivery efficiency and therapeutic effects. However, such tracking is impeded by the complex biological microenvironment leading to inhomogeneous distribution. A rotatable fluorescent ratio strategy is introduced that integrates aggregation‐induced emission (AIE) and aggregation‐caused quenching (ACQ) into one nanostructured system, termed AIE and ACQ fluorescence ratio (AAR). Following this strategy, an advanced probe, PEG5k‐TPE4‐ICGD4 (PTI), is developed to track the dynamics change. The extremely sharp fluorescent changes (up to 4008‐fold) in AAR allowed for the clear distinguishing and localization of the intact state and diverse dissociated states. The spatiotemporal distribution and structural dynamics of the PTI micelles can be tracked, quantitatively analyzed in living cells and animal tissue by the real‐time ratio map, and be used to monitor other responsive nanoplatforms. With this method, the dynamics of nanoparticle in different organelles are able to be investigated and validated by transmission electron microscopy. This novel strategy is generally applicable to many self‐assembled nanostructures for understanding delivery mechanism in living systems, ultimately to enhance their performance in biomedical applications. 相似文献
998.
针对传统仿生智能算法处理异构光伏发电功率预测精确建模问题时存在的线路多阻抗参数约束下方差波动、线损分析易陷入局部极值等不足,提出了一种基于改进深度确定性策略梯度(DDPG)的中短期光伏发电功率预测模型。首先,通过引入多智能体机制,视发电系统涉及到的发电过程参数为独立活性的智能体,构建出具有社会属性的面向发电过程参数信息共享的全局最优协同控制体系。然后,通过改进的DDPG算法实现蓄电池储能功率自主精确调节和发电网输出功率的自动最优预测。最后,基于Tensorflow开源框架在Gym torcs环境下进行模型效能仿真并以某示范性异构光伏发电网为效能评价载体,对模型进行了工程应用合理性验证。 相似文献
999.
Shu-Hung Yang Yi-Nan Lin Cheng-Ying Yang Ming-Kuen Chen Victor R. L. Shen Yu-Wei Lin 《电子科技学刊:英文版》2022,20(2):209-223
An increasing number of social media and networking platforms have been widely used. People usually post the online comments to share their own opinions on the networking platforms with social media. Business companies are increasingly seeking effective ways to mine what people think and feel regarding their products and services. How to correctly understand the online customers’ reviews becomes an important issue. This study aims to propose a method with the aspect-oriented Petri nets (AOPN) to improve the examination correctness without changing any process and program. We collect those comments from the online reviews with Scrapy tools, perform sentiment analysis using SnowNLP, and examine the analysis results to improve the correctness. In this paper, we apply our method for a case of the online movie comments. The experimental results have shown that AOPN is helpful for the sentiment analysis and verifying its correctness. 相似文献
1000.
近年来,蓝光对人眼的危害逐渐被人们所认识和关注。蓝光危害风险不仅存在于照明光源中,还存在于显示产品中。减少蓝光的含量是降低蓝光危害的直接方法。而蓝光是显示产品光谱中必不可少的组成波段,同时也是满足显示产品色温和色域需求,完美展现丰富多彩的真实世界的必需颜色。因此如何在不降低正常显示标准下,发展抗蓝光危害的技术是显示技术的一个重要研究方向。目前,国内外众多研究者围绕蓝光生物安全性及防蓝光显示技术进行了较深入的研究。本文首先阐述了蓝光危害的作用机制、危害分类和评估方法、标准,分析了显示产品中影响蓝光危害程度的多种影响因素。介绍了目前防蓝光显示技术新进展,并对防蓝光显示技术进展进行了总结和展望。 相似文献