半刚性路面基层的机械化施工

从高等级公路半刚性路面基层的施工实践出发，探讨高质量、高速度进行机械化作业的施工技术，机械组合，施工组织和施工工序     

浅谈公路路基的施工

从公路路基的施工质量要求、施工参数确定、施工注意事项、质量标准控制四个方面介绍了公路路基的施工方法。     

Multi-Band Hybrid Mobile Phone Antenna Based on Electromagnetic Coupling

This research presents a multi-band hybrid mobile phone antenna based on electromagnetic coupling,which can be applied to mobile handheld devices, occupying a small board space of 39.7 mm × 15.6 mm on the system circuit board. By adding resonant and coupled branch instead of multi-feed on the traditional bent antenna,this design provides four wide operating bands of 0.772—0.998 GHz, 1.540—1.600 GHz, 1.680—2.270 GHz and2.300—2.690 GHz with the hybrid feature of planar inverted-F antenna(PIFA), L-shape, U-shape and S-shape structures, which cover nine-band, i.e., GSM850, GSM900, GPS1575, DCS1800, PCS1900, IMT200, LTE2300,LTE2600 and Blue Tooth/Wi-Fi. Ansoft software HFSS is used in this research to make the antenna performance better and the operating principle of the proposed antenna is described in detail. Result of simulation reveals that the maximum gains of these four wide bands are 2.20,-0.99, 4.01 and 4.05 dBi, respectively. Moreover, this research also tests the return loss(S11) of the fabricated antenna with the vector network analyzer and the result is in accordance with the simulation result on the whole. There are four wide resonant frequencies which cover nine-band of wireless wide area network(WWAN), wireless local area network(WLAN) and long term evolution(LTE), when the available bandwidth is better than 6 d Bi return loss.     

现代信息技术发展对物流产业发展的影响

该文主要论述了现代信息技术对物流产业的运行方式、组织及竞争格局等几方面的影响。     

“广州”号导弹驱逐舰访问文莱、印度尼西亚

应文莱皇家海军和印度尼西亚共和国国民军海军邀请，中国海军“广州”号导弹驱逐舰于8月7日上午10时离开三亚某军港，开始了对文莱和印度尼西亚的友好访问。据悉，此次访问历时17天，“广州”号导弹驱逐舰将代表中国海军同来自亚洲、欧洲、美洲的多国海军一道，参加文莱第二届国际防务展和“2009印尼国际舰队检阅”等庆典活动。     

道路维修中路面下空洞探查技术

本文介绍了日本道路维修中路面下的空洞探查技术。     

工程风沙防护

介绍了工程风沙措施和植物固沙措施。     

沥青混凝土路面抗滑问题的探讨

阐述了路面抗滑性能对汽车制动性能的影响、路面防滑研究发展概况、沥青路面抗滑影响因素及对沥青路面防滑问题进行了探讨     

铁路工程长距离带状GNSS控制网高精度解算

铁路工程控制网三网合一,采用GNSS卫星导航定位基准站(CORS)方式建网是发展的趋势,但其长距离、带状布设的控制网要确保高精度且连续均匀,具有一定的难度。针对长距离带状控制网的特点,分析影响GNSS控制网解算的影响因素,引入IGS站点坐标的松弛约束,筛选出优化解算策略：融合多星座卫星观测数据,基于电离层约束模型求解宽巷模糊度,当控制网的基线长度小于100 km时,对流层延迟采用站间差分改正、电离层延迟采用差分或模型改正,并结合环境条件顾及其他负荷改正。实际铁路工程带状控制网解算测试表明,优化策略控制网处理精度相较于常规策略在Y和Z方向上提升2～5 mm。通过对复杂地形环境下长距离带状控制网的解算质量分析,进一步表明该策略可优化铁路工程长距离带状控制网高精度解算性能。     

Design of Cross-Shaped CPW-Fed Ultrawideband Slot Antenna

A new design of ultrawideband(UWB) antenna of coplanar waveguide(CPW)-fed is proposed. The antenna is composed of a cross-shaped patch and house-shaped slot with the minimum dimension of 21 mm ×20 mm × 1.6 mm. The analysis of S11, VSWR, radiation pattern and surface current is discussed with HFSS simulation software, and also the effect of parameters is presented. Experimental results show that the bandwidth of the antenna covers 110.67%(3.3—11.6 GHz) of UWB range with return loss better than 10 dB. And the good impedance matching in frequency band confirms the antenna is a good candidate for the application of wireless system.