GB 21520-201X显示器能效新标准解读与分析

针对GB21520-201X显示器能效新标准,结合与旧版能效标准比较所得的差异进行了相关的解读与分析。结果表明,新标准在适用范围、能源效率指标部分进行了更新,增加了高性能显示器、睡眠状态功率等概念。并通过实际的测试,对高性能显示器的标准符合性进行了分析。     

Robust partially mode‐dependent H∞ filtering for discrete‐time nonhomogeneous Markovian jump neural networks with additive gain perturbations

This paper studies the robust partially mode‐dependent H_∞ filtering for nonhomogeneous Markovian jump neural networks with additive gain perturbations. The discrete time‐varying jump transition probability matrix is considered to be a polytope set. A partially mode‐dependent filter with additive gain perturbations is constructed to increase the robustness of the filter, which is subjects to H_∞ performance index. Based on the Lyapunov function approach, sufficient conditions are established such that the filtering error system is robustly stochastically stable. The efficiency of the new technique is illustrated by an illustrative example and a biological network example.     

Widely tunable wavelength spacing dual-wavelength single longitudinal mode erbium doped fiber laser

A simple widely tunable wavelength spacing dual-wavelength single longitudinal mode (SLM) erbium doped fiber laser (EDFL) based on cascaded fiber Bragg gratings (FBGs) and birefringent fiber filter is proposed and demonstrated. Experimental results show that the lasing wavelength spacing is widely tunable in a range from 2 nm to 18 nm, which has potential to generate frequency tunable terahertz (THz) waves by beating the lasing dual-wavelength in a high speed photodetector. The birefringent fiber filter acts as an ultra-narrow bandpass filter and benefits the simultaneous oscillation of dual-wavelength in a single laser cavity. The output peak power of the lasing dual-wavelength is approximately equalized at room temperature, and a high optical signal-to-noise ratio (OSNR) is realized in the whole tuning range. The SLM operation of dual-wavelength fiber laser is verified by Fabry–Perot (F–P) scanning interferometer, and the clear eye diagram proves that the proposed fiber laser is effective in the application of fiber optic communication system.     

Quad‐Band Bandpass Filter Using Quad‐Mode Stub‐loaded Resonators

Compact multi‐band bandpass filters using quad‐mode stub‐loaded resonators are proposed in this letter. Firstly, a novel approach about the mode‐splitting characteristics of the quadruple‐mode resonator is investigated, which can provide dual‐band behavior. Secondly, a quad‐band filter is proposed and designed by cascading two quadruple‐mode resonators; the upper one operates at 1.8/2.4 GHz (GSM‐ and WiMax‐band) and the lower one at 1.57/2.1 GHz (GPS‐ and WCDMA‐band). Finally, the proposed filters have been fabricated. Respectable agreement between simulation and measurement verifies the validity of this design methodology.     

原煤识别模式在煤炭产量计量系统中的应用

为了准确计算煤矿的产量,需要把煤矸石的量减掉,针对这个问题,研究了基于图像识别的煤矸石识别技术,从煤矸石与煤炭的样本数据中分离数据,最终完成煤矸石的识别系统。采用自适应增强算法（ AdaBoost 算法）对实现目标的检测达到了很好的效果,虽然原煤图像存在着多样性,受到遮挡、光照、视角等的影响,通过Ada-Boost算法对原煤数据库和非原煤数据库训练逐步提升原煤分类器性能,能成功实现原煤识别检测。论文中识别系统充分利用图像识别技术和人工智能思想,将机器学习引入煤矸石模型的建模环节,成功实现煤炭和煤矸石的区分。     

浅议IP RAN组网架构及保护方式

随着社会经济与科学技术的高速发展,移动业务IP化的速度也逐渐加快,LTE在国内的热度越来越高,传统的单一业务、单一网络承载模式已经无法很好地满足人们的需要,运营商承载网都需要进行转型调整来面对严峻的挑战。如今国内很多运营商已经开展IP RAN综合承载网络的全面建设以适应变化的市场需求,IP RAN及承载业务的组建已成为社会的关注点之一。     

地-电离层波导中甚低频波昼夜过渡期特性研究

建立了地-电离层波导中甚低频电磁波在昼夜过渡期的传播模型,导出了计算昼夜过渡期接收点场强幅度与传播相位的理论公式,分析了季节的改变,白天和黑夜的长短等因素对其产生的影响。理论分析结果表明,接收点的相位昼夜变化近似于一个梯形,其中过渡期的变化即为两个斜边,对应的场强幅度变化出现相应的极大与极小值,而模转换干涉相位偏差即为叠加于斜边上的起伏。实验测试结果证实了理论公式的正确性。     

一种移动互联网用户行为模式评估方法及模型研究

提出了一种用户行为模式评估模型,此模型建立反向传播（BP）神经网络系统,对用户行为历史进行学习、训练、校验,最终得到稳定的神经网络形态。经过多重匹配和多次逼近后,成熟的神经网络系统模型可以实现对用户在时域与地域细分下的数据业务密度进行评估,在实际网络系统用户使用场景中,对用户分类和运营商策略给予基础理论参考和方法指引。     

导弹紫外辐射特性模拟方法研究

为了对导弹在飞行时产生强烈的紫外辐射进行模拟,对导弹紫外动态辐射特性行了分析,并对适合作为辐射源的人工紫外光源原理、特点与应用进行了描述与比较,最后对飞行特征几种控制方式与适用的光源进行阐述与比较。     

高效率低电磁干扰的升压型DC–DC转换器

A synchronous boost DC-DC converter with an adaptive dead time control （DTC） circuit and antiringing circuit is presented. The DTC circuit is used to provide adjustable dead time and zero inductor current detection for power transistors and therefore, a high efficiency is achieved by minimizing power losses, such as the shoot-through current loss, the body diode conduction loss, the charge-sharing loss and the reverse inductor current loss. Simultaneously, a novel anti-ringing circuit controlled by the switching sequence of power transistors is developed to suppress the ringing when the converter enters the discontinuous conduction mode （DCM） for low electromagnetic interference （EMI） and additional power savings. The proposed converter has been fabricated in a 0.6 #m CDMOS technology. Simulation and experimental results show that the power efficiency of the boost converter is above 81% under different load currents from 10 to 250 mA and a peak efficiency of 90% is achieved at about 100 mA. Moreover, the ringing is easily suppressed by the anti-ringing circuit and therefore the EMI noise is attenuated.