平地机耐磨衬垫的改进设计

<正>为降低牵引架与回转圈的摩擦,徐工生产的平地机都装有耐磨衬垫。图1为平地机回转圈、牵引定位用AB胶粘在牵引架上,在回转圈回转过程中起到保护牵引架和回转圈的作用。平地机工作过程中,由于回转圈与牵引架相对运动时产生的冲击,     

机械租赁经营研究

以某国有施工企业为研究对象,就其机械租赁战略进行了分析研究并从市场营销理论和市场发展战略2个角度,探讨了我国工程机械行业租赁经营的发展状况和未来发展方向。     

一种基于模拟植物生长算法的输电网故障诊断方法

将模拟植物生长算法应用于输电网故障诊断,提出了将开关及设备电流转化成整形变量的方法,建立输电网故障诊断模型.仿真实验验证了模型的正确性、有效性及高容错性.     

输电线路避雷器的应用及其安装方案

雷击是输电线路的主要危害。线路避雷器是降低线路雷击跳闸率的有效手段,我国已使用的线路避雷器运行情况良好。但由于线路避雷器价格昂贵,线路全线安装是不现实的,所以线路避雷器的安装地点和方式是一个比较重要的问题。本文对输电线路雷害事故及防雷措施进行了分析论述,并介绍了输电线路避雷器的发展及应用情况。最后结合我国多年的应用经验和计算分析,对于输电线路避雷器的安装方案提出了一些一般性的意见,并详细分析解释了这些意见的理由。     

600MW直接空冷机组启动方式分析

通过对600 MW直接空冷机组高压缸启动方式,中压缸启动方式和高、中压缸联合启动方式技术特点的比较,给出不同旁路系统选择启动方式的建议:设置一级大旁路的直接空冷机组采用高压缸启动最简单;设置两级串联旁路的直接空冷机组采用中压缸启动最优;设置两级简易旁路的直接空冷机组,当无法采用中压缸启动而采用高压缸启动又不能满足要求时,可采用高、中压联合启动.     

10Gb/s GaAs PHEMT电流模跨阻抗光接收机前置放大器

采用0.5μm GaAs PHEMT工艺研制了一种单电源共栅电流模跨阻抗前置放大器(TIA).测量得到放大器-3dB带宽为7.5GHz,跨阻增益为45dBΩ;输入输出电压驻波比(VSWR)均小于2;等效输入噪声电流谱密度在14.3～22pA/ Hz之间,平均值为17.2pA/ Hz.在输入10Gb/s非归零(NRZ)伪随机二进制序列(PRBS)信号下,放大器输出眼图清晰,具有14ps的定时抖动和138mV的峰峰电压.     

一种快速全局优化的神经网络及其在数据融合中的应用

本文将遗传算法的全局性和EM算法的快速性相结合,提出了一种快速全局优化神经网络,并将其应用于数据融合中。理论与实验结果表明该算法在数据融合中具有很强的鲁棒性。     

Lignin as a Wood‐Inspired Binder Enabled Strong,Water Stable,and Biodegradable Paper for Plastic Replacement

Plastic waste has been increasingly transferred from land into the ocean and has accumulated within the food chain, causing a great threat to the environment and human health, indicating that fabricating an eco‐friendly and biodegradable replacement is urgent. Paper made of cellulose is attractive in terms of its favorable biodegradability, resource abundance, large manufacturing scale, and low material cost, but is usually hindered by its inferior stability against water and poor mechanical strength for plastic replacement. Here, inspired by the reinforcement principle of cellulose and lignin in natural wood, a strong and hydrostable cellulosic material is developed by integrating lignin into the cellulose. Lignin as a reinforced matrix is incorporated to the cellulose fiber scaffold by successive infiltration and mechanical hot‐pressing treatments. The resulting lignin‐cellulose composite exhibits an outstanding isotropic tensile strength of 200 MPa, which is significantly higher than that of conventional cellulose paper (40 MPa) and some commercial petroleum‐based plastics. Additionally, the composite demonstrates a superior wet strength of 50 MPa. Adding lignin also improves the thermostability and UV‐blocking performance of cellulose paper. The demonstrated lignin‐cellulose composite is biodegradable and eco‐friendly with both components from natural wood, which represents a promising alternative that can potentially replace the nonbiodegradable plastics.     

Dynamic RSVP protocol

RSVP is a resource reservation setup protocol that can be used by a host to request specific QoS for multicast multimedia flows on the Internet. Multiprotocol label switching (MPLS) architecture also needs RSVP. The fact that the resolutions of the display system used in different receiver nodes might have different, multi-resolution characteristics is supported in the MPEG-4 standard, and the EZW compression algorithm can cease decoding at any point in the bitstream. However, RSVP does not provide a more flexible mechanism. In this article we propose an extension of RSVP to provide the needed mechanism, coined dynamic RSVP (DRSVP), to dynamically adjust reserved resources on nodes without much effort. It provides different video resolutions to different receiver nodes with different needed reserved resources. Therefore, it does not waste precious Internet resources to transmit unnecessary multimedia packets.