基于光纤传输的电引爆武备安全裕度测量系统的设计

电引爆武备安全裕度测量系统利用微型光纤温度传感器放置在电爆管桥丝附近,通过测量桥丝的热效应来间接测定电爆管在电磁辐射下的射频感应电流,从而对舰上的电引爆军械安全性作统一评估。系统采用光纤传输技术能很好地解决传输线在强电磁场中的引入误差,排除电测量方法中无法排除强场下自身引入干扰的问题。     

无人机提高目标定位精度方法研究

无人机电视图像定位技术,由于采用的单站测角测距方法,存在一些无法克服的不足;空间两点交会定位方法,虽然在一定程度上提高了目标定位精度,但还不能达到高定位精度要求。通过空间三点,建立了空间三点交会定位模型;并且与现有的共线定位算法相结合,通过差分定位原理,达到快速与准确获得任意点坐标的目的。     

机电产品性能进化设计的研究

加快机电产品的设计是企业保持竞争力的重要保证,本文采用实例论证了机电产品性能的进化设计是一种重要的方法.     

电渗法加固软土地基基本参数室内试验研究*

电渗法是一种处理软土地基的有效方法,其基本参数的确定在工程应用中至关重要。利用自制的电渗试验装置,对某一高含水量淤泥土进行了稳压电渗试验和稳流电渗试验,测量了电渗过程中电流、电压、出水速率的变化,总结了电渗透系数、电迁移系数、电导率和单位能耗出水速率等基本参数的变化规律。试验结果表明:随着电渗的进行,电渗透系数逐渐减小,而电迁移系数相对稳定。土体的电导率和单位能耗出水量也逐渐降低。因此,用电迁移系数来评价电渗效果可能更为合理。     

An adaptive hawkes process formulation for estimating time-of-day zonal trip arrivals with location-based social networking check-in data

Location-Based Social Networking (LBSN) services, such as Foursquare, Facebook check-ins, and Geo-tagged Twitter tweets, have emerged as new secondary data sources for studying individual travel mobility patterns at a fine-grained level. However, the differences between human social behavioral and travel patterns can cause significant sampling bias for travel demand estimation. This paper presents a dynamic model to estimate time-of-day zonal trip arrival patterns. In the proposed model, the state propagation is formulated by the Hawkes process; the observation model implements LBSN sampling. The proposed model is applied to Foursquare check-in data collected from Austin, Texas in 2010 and calibrated with Origin-Destination (OD) data and time of day factor from Capital Area Metropolitan Planning Organization (CAMPO). The proposed model is compared with a simple aggregation model of trip purposes and time of day based on a prior daily OD estimation model using the LBSN data. The results illustrate the promising benefits of applying stochastic point process models and state-space modeling in time-of-day zonal arrival pattern estimation with the LBSN data. The proposed model can significantly reduce the number of parameters to calibrate in order to reduce the sampling bias of LBSN data for trip arrival estimation.     

Qualitative evaluation study of urban shared spaces in New Zealand

This paper presents the findings of a qualitative analysis using on-street perception and expert interview surveys of city centre streets that have been transformed into shared spaces in Auckland, New Zealand. The principal purpose was to investigate how well the shared streets performed, especially in relation to movement, access and place functions. The shared space sites at the Elliott, Lorne and Fort Street areas were measured against the performance criteria of Placemaking, Pedestrian Focus, Vehicle Behaviour Change, Economic Impetus and Safety for all users. On-street perception surveys totalling 360 responses (120 per site) were used in this study, together with an additional set of 40 responses from a survey of a control site in O’Connell Street that remained as a traditional street. Fifteen professionals with background in transportation and urban planning participated in semi-structured expert interviews. The main results of the Median Perception Ratings from the on-street surveys confirmed that the shared spaces generally performed positively. The statistical analysis revealed that the performance criteria of ‘Pedestrian’ and ‘Safety’ had a commanding influence over the other performance measures, and with the interconnectivity of the five objectives the perceived success of the urban shared spaces.     

电压型PWM整流器电流空间矢量控制研究

针对如何提高电压源型三相PWM整流器交流侧电流的控制速度问题,本文提出了控制和调制相结合的两种控制策略,即电流的空间矢量滞环控制策略和优化的电流空间矢量控制策略。本文分别对这两种控制策略进行了仿真,仿真结果验证了两种策略的有效性。     

基于MSC.Patran的舱室识别程序开发

针对船舶结构强度规范校核时对舱室空间的边界单元自动识别的需要,对有限元模型空间识别方法进行讨论,以Patran为开发平台,使用PCL语言,基于"切分拼接"的思想开发出舱室空间识别程序,所开发的舱室识别程序能够准确地识别出舱室的边界网格单元。     

一种船用智能电动阀门电气性能调试装置的设计

为了避免性能不合格的电动阀门被安装在重要位置上而带来的安全隐患,电动阀门在上船安装前必须进行电动性能检测.根据设备厂不能为用户提供相应的调试装置的实际情况,为了满足生产的需求,本文研制出一套船用智能电动阀门调试装置.实际使用结果表明：该装置运行良好,达到设计要求.     

信息栅格环境下美军数据策略研究综述

《网络中心的数据策略》为美军基于全球信息栅格（GIG）的信息系统数据管理提供了顶层指南,其核心思想就是要确保信息栅格环境下的数据的可视、可获取和可用。论文首先描述了美军《网络中心的数据策略》的基本概念,接着重点阐述了美军在信息栅格环境下实现数据策略的三大关键因素,即＂关联群体＂、＂元数据＂和＂GIG企业服务＂,最后分析了美军实现GIG数据共享的处理方式——信息共享空间。