单载波频域均衡的NP算法研究与FPGA实现

针对单载波的频域均衡时色噪声对系统性能的影响,提出一种NP(noise predictor)算法来去除色噪声.通过NP算法去除了相邻样值的相关性,使得色噪声得到白化,并且通过仿真验证结果表明NP算法可以很好地消除单载波频域均衡时色噪声的影响.此外,在算法实现中采用8倍时分复用的降频方法,使用组划分,在保证性能的同时节约了硬件资源,还提高了工作频率.     

试析高速公路改扩建工程扩堑爆破施工技术

以昆嵩高速公路扩改建工程为例,阐述了高速公路改扩建工程扩堑爆破施工技术。     

论国有企业的国际营销：环境与策略

经济全球化使得国有企业必须对于国际市场有所重视,从而扩展自身的市场规模,提升销售量与利润。本文通过对国有企业的出口环境及国际市场环境进行分析,从四个方面入手提出了一系列提升国有企业国际营销策略的措施。     

翻开罗孚百年史的荣耀

曾经是帝国的荣耀,经历过战争的考验,也曾几经转手,而今,我们翻开罗孚的历史,也就翻开了帝国当年的荣耀。当我们谈论汽车及其相关历史的时候却很少提及仍然是工业强国的英国。这种现象也许是英国现在汽车工业是窘迫局面造成的,疲软的英国汽车工业让人们已经淡忘了它的历史,但实际上,英国的汽车工业增提供给世界一大批优秀的车型和品牌,比如劳莱斯、宾利、阿斯顿·马丁、捷豹、摩根以及今天我们要讲述的罗孚(Rover)。     

高速磁浮列车分区运行控制系统可靠性提高方法研究

分区运行控制系统是实现高速磁浮列车运行指挥及安全防护的安全苛求计算机控制系统。本文借鉴上海同济大学1.5km高速磁浮列车试验线的分区运行控制系统工程样机研制与现场运行调试经验,建立状态回采模型。基于该模型提出一套适用于高速磁浮列车分区运行控制系统软件的可靠性提高方法:状态回采法,并从理论上证明了这种方法的可行性,最终将该方法运用于分区运行控制系统,提高了其可靠性,为高速磁浮列车分区控制系统的国产化工作提供了技术支持。     

Distribution Laws of Fire Temperature Fields in Immersed Tunnel: A Case Study of Hong Kong Zhuhai Macao Bridge Immersed Tunnel Project（沉管隧道火灾温度场分布规律研究——以港珠澳大桥沉管隧道为例）

The large testing platform for immersed tunnel is established to analyze the distribution laws of the temperature field and its influencing factors when a tunnel fire breaks out. Meanwhile, the combination method of physical testing (1∶1 full scale fire test) and numerical calculation FDS are applied. Some conclusions are drawn as follows: (1) Longitudinal wind speed within limits can decrease the maximum temperature of tunnel crown top effectively when fire breaks out in tunnel. (2) The maximum temperature of tunnel crown top and fire behavior are related to fire types obviously. (3) The high temperature resistance safe position of the tunnel equipment is below 3.5 m of tunnel sidewall in case of fire source heat quantity of 50 MW. (4) The fire maximum temperature is positively related to heat release rate (HRR) and longitudinal wind speed.     

从用户声音洞察乘用车产品发展趋势

把握乘用车产品发展趋势是汽车企业占领市场先机的重要途径。本文介绍一种从用户声音中筛选、提炼得到用户需求点或认知点的研究方法——VOC研究,并基于这种研究方法,通过搜集190位汽车用户的声音,捕捉到未来乘用车产品的六个发展趋势:从被动安全转向主动安全,车内环保性问题不容小觑,车载互动服务方兴未艾,电子娱乐需求不断涌现,操作便利化/简单化渐成趋势,发动机节油或新能源渐受青睐。     

General Design of Shenzhen Zhongshan River crossing Link Project（深圳至中山跨江通道工程总体设计）

Shenzhen Zhongshan River crossing Link is the first super integrated project in the world that consists of four different types of structures, i.e. ultra long and wide immersed tunnels, super large span sea crossing bridges, deep water artificial islands and undersea interchanges. The river crossing is designed for two way and 8 lane as per highway technical standards. Based on project characteristics and its technical difficulties, engineering solutions and the associated technology innovations have been listed as follows: (1) Proposed a design concept of standardization, industrialization, intelligence and project integration, and completed the study of overall design of Shenzhen Zhongshan River Crossing Link. An immersed tunnel with a combined steel shell and concrete composite structure is designed and the width of tunnel elements is from 46 to 55.5 m; Lingdingyang Bridge has been designed as a suspension bridge with a 1 666 m main span and two 270 m high main bridge towers. For West Island, a temporary enclosure caisson structure made of ultra large steel cylinders with a diameter of 28 m is designed to achieve a rapid artificial island formation. (2) Summarized the design and construction solutions related to combined steel shell and concrete structural immersed tunnel, the mix design, batching and concrete casting methods of high strength self compacting fluidized concrete, concrete quality check and inspection, design and construction of deep cement mixed (DCM) pile foundation for immersed tunnels, design and construction of large scale undersea dimensional transport interchange, flutter and wind stability design for super large span suspension bridge with monobox girders, and key techniques related to design and construction of offshore anchorage in deep sea. Furthermore, an equipment is developed and innovated for not only transport, also for installation of immersed tunnel elements to ensure the implementation of the project in an effective and economical way.     

基于综合相似度的地铁施工风险应急推理研究

针对地铁项目施工环境复杂、不可预见因素多、施工事故频发、难以对其进行快速有效的应急决策与救援的问题,首先,搜集以往地铁施工应急案例,分析地铁施工风险因素,运用Protégé软件建立知识本体模型;然后,计算本体库中源案例与目标案例的综合相似度,从案例库中匹配出综合相似度最大的源案例,通过对比本体库中与目标案例相似度最高源案例的关键属性,运用规则推理对相似案例的应急措施进行适用性修改,从而提高应急措施的针对性,为快速有效地应对地铁施工事故进行应急决策提供新的方法;最后,以某地铁项目施工为例,验证了该相似度算法的合理性。     

地铁换乘基坑环框支撑结构关键技术分析

为解决地铁换乘站基坑支护工程设计及施工风险问题，通过分析换乘站基坑特点，优化地铁换乘站基坑首层平面轮廓为圆形，运用圆形环框梁抗压性强的特点布置圆形环框梁支撑体系。该体系具有变形易控制、拆撑风险低、工序方便快捷等优点。以广州地铁21号线天河公园站和南通地铁文化公园站为例，验证其实用性，以期为类似工程提供参考。