对以太网无源光网络中OAM的分析

以太网无源光网络(EPON)作为一种新兴的接入技术,需要网络设计者提供电信级(Carrier-class)的管理能力,而单纯的简单网络管理协议(SNMP)已经不能胜任其运营、管理、维护(OAM)的要求.文章提出了基于802.3ahOAM协议和SNMP的EPON系统管理机制,并描述TEPON系统OAM的功能、特点以及在Linux操作系统下该刚络管理机制的软件实现方案.     

A 20.8-Gbps Dual-Carrier Wireless Communication Link in 220-GHz Band

With the successful demonstration of terahertz (THz) high-speed wireless data transmission,the THz frequencies are now becoming a worth candidate for post-5G wi...     

Measurements and Characterization for the Vehicle-to-Infrastructure Channel in Urban and Highway Scenarios at 5.92GHz

In the future smart transportation system, reliable vehicle-to-infrastructure(V2 I) communication is very important to ensure vehicle driving safety and to improve vehicle driving efficiency. In this paper, V2 I channel measurements at 5.92 GHz are conducted in typical urban and highway scenarios.The frequency and bandwidth of transmission, as well as the deployment of the RSU(roadside unit) and the OBU(on board unit), are selected by considering the recommendation proposed by 3 GPP TR 36.885. T...     

Biological analysis of woodpecker’s brain after impact experiments

Woodpeckers can withstand a fierce impact during pecking. Previous studies have focused on the biomechanical analysis of the pecking process, the properties of the beak and hyoid bone of woodpecker; however, the biological characteristics of the woodpecker brain are also important in resisting impact injuries. We employed impact experiments and biological analysis in normal and injured brains to reveal the impact-resistant biological characteristics of woodpecker brains, as well as the impact energy's biological effects on the woodpecker brain. The hoopoe, which has a similar size but only a slight pecking behavior, was selected as the control group to compare brain morphology and neuronal cells differences in normal brains between woodpecker and hoopoe by sectioning and staining. A loading device was designed to conduct a quantifiable impact energy to the woodpeckers' head. Four groups of woodpeckers were impacted with the same energy on the forehead, beak, tempus and occiput,respectively. Biological changes in the injured brains were evaluated by Nissl staining and enzyme-linked immunosorbent assay.The results showed that:(1) woodpeckers had a larger cerebellum and a higher density of Nissl bodies than hoopoe;(2) Nissl apoptosis appeared in the brain samples after the forehead and the occiput impact experiments, but no obvious Nissl body apoptosis was observed after impact on the tempus and the beak;(3) β-amyloid protein accumulated in the normal status woodpecker brain. This study reveals that: woodpecker brain morphology is well-adapted to impact, woodpecker heads display location-dependent protective performance, with beak and tempus regions having a better protective performance than the forehead and occiput, Nissl apoptosis appears in injured woodpecker brains, and that the accumulation of β-amyloid protein does not show a direct relationship with the injury state of woodpecker's brain tissue in our study.     

船用热轧球扁钢的研制与开发

安钢根据市场需求,通过合理的工艺设计及严密的生产组织,研制开发出船用热轧球扁钢。产品力学性能、几何尺寸和表面质量等完全达到国标GB9945—2001及ABS、CCS、BV、LR、GL等五国船规技术要求。     

Diagnosability of crossed cubes under the comparison diagnosismodel

Diagnosability of a multiprocessor system is an important study topic in the parallel processing area. As a hypercube variant, the crossed cube has many attractive properties. The diameter, wide diameter and fault diameter of it are all approximately half those of the hypercube. The power with which the crossed cube simulates trees and cycles is stronger than the hypercube. Because of these advantages, the crossed cube has attracted much attention from researchers. In this paper, we show that the n-dimensional crossed cube is n-diagnosable under a major diagnosis model-the comparison diagnosis model proposed by Malek and Maeng (1981) if n ⩾ 4. According to this, the polynomial algorithm presented by Sengupta and Dahbura (1992) may be used to diagnose the n-dimensional crossed cube, provided that the number of the faulty nodes in the n-dimensional crossed cube does not exceed n. The conclusion also indicates that the diagnosability of the n-dimensional crossed cube is the same as that of the n-dimensional hypercube when n ⩾ 5 and better than that of the n-dimensional hypercube when n = 4     

伪三色LED图文显示屏的设计及实现

介绍由８０３１单片机控制的伪三色ＬＥＤ图文显示屏的构成,硬件结构和抗干扰措施。     

VB和VC的混合编程在点火线圈测试平台中的应用

阐述了一个基于PC的点火线圈数据采集处理系统。在VB本身的功能局限的情况下,采用VB和VC的混合编程来对Ю口进行操作。     

烟气换热器清洗工艺的选择与质量评价

对烟气换热器(GGH)离线高压射流、离线化学药剂喷淋+高压射流、拆卸解包逐片高压射流、拆卸化学浸泡+高压射流、拆卸解包化学浸泡+高压射流5种清洗工艺进行了分析对比,提出应综合考虑GGH实际情况、检修时间和经费等因素选择合理清洗工艺,并对清洗后的换热元件解包进行验收.建议选择清洗效果彻底的清洗工艺,以避免后期维修费用的增加.     

应用单光子计数器测量尼龙－11的热释光

本文给出了一种适用于热蜂光测量的单光子计数器，并用该计数器对奇数尼龙－１１薄膜进行了实际测量．结果表明，本计数器完全满足测量微光（光功率＜１０－１５Ｗ）要求．