舰用电子设备结构可靠性模糊综合评估研究

雷达等军用电子设备的可靠性,主要取决于电信功能的稳定性和结构的可靠性。文章根据军用电子设备结构系统失效模式的多样性、相关性、不同程度性及其失效过程的模糊性等特点提出了结构可靠性的模糊综合评估方法,给出了具体的综合评估数学模型和公式,并以某舰用电子设备结构系统为例说明了该方法的应用过程。     

语言与图像的协作——基于一则食品广告的多模态语篇分析

传统的广告语篇分析基本上集中在语言分析,忽视非语言符号资源对语篇意义构建所起的作用,最近兴起的多模态语篇分析在很大程度上突破了这个局限。以Halliday的系统功能语言学以及Kress和van Leeuwen的视觉语法为理论框架,通过分析一则多模态广告语篇,发现语言与图像两套符号资源以其各自独特的方式,通过互相增强或补充形成合力,共同构建语篇整体意义并取得广告最佳的说服效果。     

企业经营决策模拟平台的分析与设计

通过分析现实企业经营决策的步骤和流程,设计出该平台应包含的功能模块,着重研究了企业经营决策制定的模型和原理,并进行了详细的财务指标分析,结果表明,决策模拟平台的设计是切实可行的。     

自编码扩频通信的捕获

自编码扩频通信的扩频序列是由待传输的信息中获得的,这种特殊性决定了其同步捕获方式的不同.提出一种基于发送同步码并周期复位的同步方案.理论分析及实验仿真表明,在高斯白噪声信道中,该捕获方案的性能接近传统扩频通信的同步捕获方案,且同步码周期的提高能有效改善其捕获性能.     

辅助墩对多塔斜拉桥力学行为的影响

为改善多塔斜拉桥受力性能,在边跨设置辅助墩,采用有限元法分析辅助墩对多塔斜拉桥力学行为的影响,讨论辅助墩对不同结构布置的四塔斜拉桥的静力行为的影响.结果表明,设置边跨辅助墩能在一定程度上降低多塔斜拉桥的塔顶水平位移、跨中挠度、跨中弯矩和塔根弯矩,对提高结构刚度有一定效果;对已采取其它加劲措施的四塔斜拉桥,设置边跨辅助墩有利于进一步提高结构整体刚度.     

贝雷梁挂篮设计与应用

挂篮是构造箱梁施工的主要设备之一,种类繁多,造价也各不相同,在施工过程中,需根据实际情况选用.以楠木渡战备大桥为例.对由贝雷粱组拼的简易挂篮在连续刚构中的设计及应用作一介绍,对于挂篮的合理选用具有一定的现实意义.     

基于移动终端的路灯控制器无线组网系统设计

针对现有路灯系统运行参数无法集中控制、故障无法及时发现检修等问题,本文介绍了一个以CC2530无线自组网模块为核心,以HMI人机界面为移动控制终端的太阳能路灯控制器监测系统。该系统以CC2530F256为主控芯片;从系统的整体设计方案、移动控制终端节点和路灯系统节点的硬件设计、软件设计和系统的丢包率测试等几个方面对系统进行了介绍;经实验获得的实测数据表明,设计的系统具有丢包率低、性能稳定、实时性强的特点,而且可移植性强,在智能家居,在线水质和土壤监测等领域也可有广泛的应用。     

Law and Characteristics Analysis of Domestic Tunnel Construction Accidents from 2006 to 2016北大核心CSCD

With the rapid development of tunnel construction in China, strengthening statistical studies of domestic tunnel construction accidents is of great significance in order to understand the safety status of tunnel construction and the development trends of tunnel construction accidents and for exploring the direction of future scientific re-search. There were 89 tunnel construction accidents in China (not including subway tunnels or municipal tunnels)from 2006 to 2016. The characteristics of these accidents are analyzed in terms of time distribution, spatial distribu-tion, grade and type of accident according to the statistics by means of line charts, bar charts and pie charts. Corre-sponding prevention and control recommendations are put forward considering the factors such as year, month, work-ing day, time period, region, location, grade and type. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

A disaggregate study of urban rail transit feeder transfer penalties including weather effects

Transfers between urban rail transit (URT) and its feeder modes represent a considerable barrier to its ridership and the network-wide usage of public transit. The aim of this research is to quantify the time-independent transfer penalty between URT system and feeder modes and to explore its variability by different factors. Based on Melbourne URT origin and destination survey data, this study focused on URT access and egress journeys and estimated URT feeder transfer penalties by formulating feeder mode choice models. With three-hourly weather data and demographical data introduced, this paper conducted disaggregate analyses to investigate the variability of URT feeder transfer penalty across weather conditions, trip types and individual characteristics. According to the model estimation results, the values of transfer penalty vary according to the direction of transfer and the preference ordering for different transfer combinations is URT-tram, URT-bus, tram-URT, bus-URT and auto-URT. It found that local weather elements in terms of air temperature and precipitation are significant factors resulting in the variability of the transfer perception by URT travellers. Transfer penalties for access journeys increase with the rise of air temperature. The non-linear effects of precipitation on URT feeder transfer penalties were observed. In addition, commuters perceive smaller transfer penalties than other travellers for all of the transfer combinations except for bus-URT transfers. Travelers from remote areas perceive smaller transfer penalties for access trips. Travellers’ loyalty to public transit restrains transfer penalties. The male travellers perceive higher transfer penalties than the female. The elderly travellers impose low transfer penalties to access journeys but high transfer penalties for egress journeys. Finally, the paper explored policy implications and details areas for future research.     

支撑式TBM掘进中途的主轴承更换及处理

文章简要介绍了辽宁省大伙房输水一期工程输水隧洞TBM法施工中途,先后发生过的两次不同结构类型主轴承从异常到损坏的过程及相应的更换处理方法.鉴于国内已采用TBM法施工的隧洞(道)工程,均无一例处理过此种最不利工况的先例,本工程所经历的经验教训,应具有一定的指导意义.