在基于GMPLS的无源光网络中支持端到端QoS

文章首先对下一代网络技术的发展趋势以及IETF服务质量（QoS）机制进行了简单介绍,然后对现有无源光网络技术对端到端QoS支持的不足进行了总结,提出了基于通用多协议标签交换（GMPLS）的无源光接入网QoS服务模型。通过在接入网中引入GMPLS通用控制和管理平台,建立了统一的QoS服务模型,实现了对端到端QoS的有效支持。     

一种在电路SOC验证接口设计方法研究

SoC已经成为嵌入式系统设计中的关键器件,验证又是SoC设计的关键环节,占用SoC设计过程中60%以上的时间.专用测试设备及JTAG接口等主流SoC验证手段不便于SoC在系统联调时的验证.本文介绍了一种在电路SoC验证接口的设计方法,这种验证方法弥补了主流SoC验证方法在系统验证的不足,提高了SoC验证的效率.     

Electrochemical Oxidation of 5-Hydroxymethylfurfural on CeO2-Modified Co3O4 with Regulated Intermediate Adsorption and Promoted Charge Transfer

Electrocatalytic 5-hydroxymethylfurfural oxidation reaction (HMFOR) can replace the kinetically slow oxygen evolution reaction to yield high value-added chemicals. In this study, interface engineering is constructed by modifying CeO₂ nanoparticles on Co₃O₄ nanowires supported by nickel foam (NF). The construction of the heterointerface can facilitate the structural evolution of catalysts and charge transfer, as a result, the successfully synthesized NF@Co₃O₄/CeO₂ exhibits higher 5-hydroxymethylfurfural conversion (98.0%), 2,5-furandicarboxylic acid (FDCA) yield (94.5%), and Faradaic efficiency (97.5%) at a low electrolysis potential of 1.40 V_RHE compared to NF@Co₃O₄ and NF@CeO₂. Density-functional theory calculations indicate that the establishment of heterointerface can effectively regulate the intermediate adsorption and promote electron transfer, which greatly reduces the activation energy of the dehydrogenation step in 5-formyl-2-furancarboxylic acid (FFCA), and promotes the further oxidation of FFCA to FDCA, thereby improving the performance of HMFOR. In this study, the HMFOR behavior of the Co₃O₄/CeO₂ interface effect is deeply explored, which provides guidance for the future design of heterointerface catalysts with efficient HMFOR performance.     

激光雷达能见度仪数据采集系统的研制

目前的激光雷达能见度仪基本上都是靠通用数据采集卡进行数据采集,使用起来多有不便.针对这一现状,研制了一套适用于激光雷达能见度仪的专用数据采集系统.系统硬件基于FPGA设计,通过硬件逻辑实现计数、触发和数据存储.系统通过USB2.0高速接口与计算机连接,数据传输速度快、连接方便且支持热拔插.采集软件为采用LabWindo...     

高压直流接地极对管道电磁阀的干扰影响研究

针对高压直流输电(HVDC)接地极处于单极大地回路运行工况下,很大的入地杂散电流可能产生电磁阀发生误动作的风险,影响管道正常运行。建立了传导干扰对电磁阀线圈影响的数学模型,研究了直流杂散电流引起电磁阀误动作的机制。采用数值模拟的方法,建立国内某1 100 kV特高压直流输电工程接地极对附近管道干扰的仿真模型,并设计了管地电位实时数据采集系统。仿真及现场测试结果表明,干扰电压以接地极距离管道最近位置为中心,依次向上下游递减;冬季电磁阀受到的直流干扰是夏季的3.43倍;仿真结果和实测结果基本吻合,误差在10%以内;沿管线增设4个和6个绝缘接头后使得管地电位差降低62.1%、71.4%。为可靠预防电磁阀异常工作,在冬季应该加强阀室巡检,并沿管道上下游适当位置安装绝缘接头。     

Extending Anisotropic Perfectly Matched Layer Absorbing Boundary Condition to Biaxial Media

The absorbing boundary condition required for an anisotropic perfectly matched layer for materials that exhibit a uniaxial and biaxial permittivity tensor is investigated. These materials are used in optical and millimeter wave devices and other particular situations such as in the construction of modern aircraft and automobiles. The derivation presented in this paper may be not suitable for all the arbitrary orientations but for many common situations. The effectiveness of the condition is also illustrated with examples by the finite-difference and finite-element method.     

Android恶意软件检测技术分析和应用研究

针对Android平台安全问题,提出了手机端和服务端协作的恶意代码检测方案,手机端应用主要采用基于permission检测技术,实现轻量级的检测。服务端检测系统主要负责对手机端提交的可疑样本进行检测,同时实现了软件行为分析,特征库更新,与手机端同步等功能。其中服务端检测技术包括基于permission检测技术、基于字节码静态检测技术和基于root权限的动态检测技术。实验测试结果表明,3种检测技术能达到较好的检测效果。     

An improved look-up table predistortion technique for HPA with memory effects in OFDM systems

It is well known that HPAs (High Power Amplifiers) are inherently nonlinear devices and many researches have focused on the predistortion for memoryless HPAs. However, memory effects of HPAs can no longer be ignored when communication systems have wider bandwidth. Memoryless predistortion techniques proposed previously seldom have satisfactory effectiveness for typical wideband applications such as OFDM (Orthogonal Frequency Division Multiplexing) systems. In this paper, an improved adaptive predistortion method called 2D LUT (2-dimension look-up table) with different accuracy levels is presented to linearize HPAs with memory effects. Simulation and experimental results show that 2D LUT implements excellent performance in mitigating the signal deterioration caused by memory effects, both rectifies the signal constellation distortion and suppresses the spectrum emission. Large scale matrix computation is also avoidable in these adaptive algorithms, which makes them feasible when a real-time system is necessary.     

Electrospinning Multilayered Scaffolds Loaded with Melatonin and Fe3O4 Magnetic Nanoparticles for Peripheral Nerve Regeneration

Peripheral nerve injury is a common clinical problem bringing heavy burden to patients, due to its high incidence and unsatisfactory treatment. Nerve guidance conduit (NGC) is a promising scaffold for peripheral nerve repair, and bioactive agents are applied for great functional recovery. Melatonin (MLT) and Fe₃O₄ magnetic nanoparticles (Fe₃O₄‐MNPs) are proven to inhibit oxidative stress, inflammation, and induce nerve regeneration. Herein, a multilayered composite NGC loaded with MLT and Fe₃O₄‐MNPs is designed for sequential and sustainable drug release, creating an appropriate microenvironment for nerve regeneration. The composite scaffold shows sufficient mechanical strength and biocompatibility in vitro, and evidently promotes morphological, functional, and electrophysiological recovery of regenerated sciatic nerves in vivo. This work proves that the multilayered conduits show great prospect in the long‐term nerve defects treatment due to easy manufacture and desired efficacy.     

软交换网络监控模型的设计与应用

随着以软交换为核心的下一代网络的发展,如何在软交换网络中实现监听和控制成为了热点问题.文章重点研究了软交换网络自身的特性,分析了现有的软交换网络监听接口规范存在的不足之处,给出了一种可以同时实现对网络监听和接续控制的软交换网络监控模型设计方案.文章最后以SIP(会话初始协议)网络为例对该方案的应用进行了描述,并对监控的流程进行了具体的说明.