700MHzLTE网络部署探讨

通过分析3G网络建设运营中频谱对业务发展的重要作用,指出我国现有LTE频谱分配中缺乏1GHz以下优质频谱,不利于LTE业务发展。结合国际700MHz LTE应用和国内广电模数转换退频分析,提出推动我国700MHz LTE网络部署实施需要关注的问题,并给出相应解决建议。     

基于TinyOS的无线传感器网络节点设计与实现

针对无线传感器网络节点,首先从硬件上设计了一个无线传感器节点硬件平台,采用MSP430F5438A和915 MHz射频相结合的方案,具有比一般节点更强的处理性能和更远的传输距离。软件方面,以Tiny OS作为嵌入式操作系统,针对该节点平台进行移植,降低了节点应用开发难度,且具有很高的代码移植性。最后,通过组网实验和与Telos B节点、Mica Z节点的性能对比测试,验证了该节点平台的有效性和可靠性。     

深圳和珠海350MHz TETRA数字集群技术试验网

文章在介绍公安350MHz TETRA数字集群试验网测试内容的基础上．详细地说明了深圳和珠海试验网的系统结构、功能和特点，并给出了试验网的测试结论。     

基于RFID高频技术的洗衣管理系统

介绍了RHD高频13.56 MHz的工作原理,并基于该技术提出了一种洗衣管理系统,可有效识别衣服或布草的洗涤次数、类型和数量,大幅提高工业洗衣企业的管理效率.     

AL700在视频切换中的应用

本文介绍了AVERLOGIC公司彩色视频分割控制芯片AL700的内部结构和主要性能，给出了一个以该芯片为切换元件的视频切换器的电路设计。在本设计中，单片机通过对AL700寄存器的编程达到对视频图像的显示性质和通道切换的控制，电路硬件简单，软件实现容易，可以应用在监控系统、会议电视、可视电话等需要视频切换的场合。     

700MHz频段5G网络广播电视系统干扰问题研究

在700 MHz频段5G网络运营中存在广播电视系统的同频干扰风险,严重影响网络性能。从广播电视系统的频率配置出发,首先,探讨了700 MHz频段5G网络受广播电视系统干扰的原理;然后,分析广播电视系统干扰特点,并针对这些特点提出了基于频域信息的广播电视系统干扰识别算法;最后,对算法识别的准确性进行测试验证,实现通过干扰识别支撑干扰优化、规避的目标。     

球墨铸铁曲轴激光淬火试验研究

介绍了激光淬火球铁曲轴的优点,提出了一种激光淬火球铁曲轴圆角部分扫描的新方法。通过优化激光淬火球铁曲轴的参数,对球铁曲轴进行了实验,实测了激光淬火后硬化层的深度、表面硬化层的硬度及表面残余应力。实验还表明曲轴激光淬火前后变形量较小,抗疲劳性能优良,淬火带内存在较大残余压应力,为改进曲轴表面处理方法提供了依据,具有广泛的应用前景。     

集聚纺纱系统成纱原理及装置分析

本文详细介绍了COM4、EliTe和Air-Com-Tex700集聚纺纱系统的纺纱原理，并对各种集聚纺纱系统存在的问题及不足进行了分析。     

Cooling performance of grid-sheets for highly loaded ultra-supercritical steam turbines

In order to increase efficiency and achieve a further CO₂-reduction, the next generation of power plant turbines will have steam turbine inlet temperatures that are considerably higher than the current ones. The high pressure steam turbine inlet temperature is expected to be increased up to approximately 700°C with a live steam pressure of 30MPa. The elevated steam parameters in the high and intermediate pressure turbines can be encountered with Ni-base alloys, but this is a costly alternative associated with many manufacturing difficulties. Collaborative research centre 561 “Thermally Highly Loaded, Porous and Cooled Multi-Layer Systems for Combined Cycle Power Plants” at RWTH Aachen University proposes cooling the highly loaded turbines instead, as this would necessitate the application of far less Ni-base alloys. To protect the thermally highly loaded components, a sandwich material consisting of two thin face sheets and a core made from a woven wire mesh is used to cover the walls of the steam turbine casing. The cooling steam is led through the woven wire mesh between the two face sheets to achieve a cooling effect. The wire mesh provides the grid-sheet with structural rigidity under varying operating conditions.In the present work, the cooling performance of the grid-sheets will be investigated applying the conjugate heat transfer method to ultra-supercritical live and cooling steam conditions for a section of the cooling structure. The behaviour of the flow and the heat transfer in the grid-sheet will be analyzed in detail using a parameter variation. The numerical results should give a first prediction of the cooling performance under future operating conditions.     

终轧温度对700MPa级高强板性能的影响

采用TMCP工艺生产低碳贝氏体钢时,合理的工艺制度是得到优良综合性能的保障。本文通过不同终轧温度的工艺试验,探讨了终轧温度对700MPa级高强板性能的影响。