Mental maps compared to actual spatial behavior using GPS data: A new method for investigating segregation in cities

This article examines the relationship between perceived territorial boundaries and actual spatial activity. The methodology used includes a combination of mental maps and interviews for examining perceptions of territorial boundaries, with tracking technology (GPS) and activity diaries to track the actual use of space. This methodology was implemented in a pilot study with a sample of 18 women living in Jerusalem, including secular Jews, ultra-orthodox Jews, and Palestinian Muslims.The study found a very strong relationship between perceived personal territory and actual spatial activity. However, while the secular Jewish women appeared to be completely segregated within their territory, the ultra-orthodox Jewish women and the Palestinian Muslim women were both very active within the secular Jewish territory, but avoided each other’s territories. The analysis of mental maps and actual spatial patterns of residential daily activities challenges prevailing notions about the spatial structure of Jerusalem and the internal power relations between the populations that inhabit it. More generally, it provides a new methodological approach for investigating segregation in cities.     

面向先进装备制造业的室内空间测量定位系统

在以航天航空、造船为代表的大型装备制造业中,精密测量技术是产品质量的重要保证,目前以激光跟踪仪为代表的传统单站式测量系统已无法适应如今超大空间与高效率的测量要求。作为分布式测量系统,室内空间测量定位系统因其扩展性好、可并行测量等优势,已被广泛应用于先进装备制造业。本文详细阐述了室内空间测量定位系统的基本传感机理,梳理总结了整套系统的关键技术,并介绍了室内空间测量定位系统的相关工业应用。     

Received signal strength based positioning for multiple nodes in wireless sensor networks

We address the problem of locating multiple nodes in a wireless sensor network with the use of received signal strength (RSS) measurements. In RSS based positioning, transmit power and path-loss factor are two environment dependent parameters which may be uncertain or unknown. For unknown transmit powers, we devise two-step weighted least squares (WLS) and maximum likelihood (ML) algorithms for node localization. The mean square error of the former is analyzed in the presence of zero-mean white Gaussian disturbances. When both transmit powers and path-loss factors are unavailable, two nonlinear least squares estimators, namely, the direct ML approach and combination of linear least squares and ML algorithm, are developed. Numerical examples are also included to evaluate the localization accuracy of the proposed estimators by comparing with two existing node positioning methods and the Cramér–Rao lower bound.     

Adaptive fuzzy neuro-observer applied to low cost INS/GPS

A combined MEMS Inertial Navigation System (INS) with GPS is used to provide position and velocity data of land vehicles. Data fusion of INS and GPS measurements are commonly achieved through a conventional Extended Kalman filter (EKF). Considering the required accurate model of system together with perfect knowledge of predefined error models, the performance of the EKF is decreased due to unmodeled nonlinearities and unknown bias uncertainties of MEMS inertial sensors. Universal knowledge based approximators comprising of neural networks and fuzzy logic methods are capable of approximating the nonlinearities and the uncertainties of practical systems. First, in this paper, a new fuzzy neural network (FNN) function approximator is used to model unknown nonlinear systems. Second, the process of design and real-time implementation of an adaptive fuzzy neuro-observer (AFNO) in integrated low-cost INS/GPS positioning systems is proposed. To assess the long time performance of the proposed AFNO method, wide range tests of a real INS/GPS with a car vehicle have been performed. The unbiased estimation results of the AFNO show the superiority of the proposed method compared with the classic EKF and the adaptive neuro-observer (ANO) including a pure artificial neural network (ANN) function approximator.     

基于工件定位误差修正算法的无心磨削过程仿真研究

为合理地描述无心磨削过程,提出了一个关于工件表面误差引起的定位误差的修正算法,建立了基于该算法的无心磨削静态成圆仿真模型.通过VB6.0编程及MATLAB6.5仿真分析.在嵌入与生产实际相符的数据后,可得到磨削过程中的工件圆度误差变化曲线.通过对比,表明所提算法是合理的.     

跨区域CORS系统基准站选址测试数据处理与分析研究

讨论了跨区域CORS系统建设过程中基准站站址测试数据处理的流程与方法,提出了从观测数据完好性、数据质量、单点定位结果以及基线解算等四个方面对CORS系统基准站选址进行分析与评价,并结合武汉城市圈CORS系统建设的实例进行分析.通过实测数据的处理,表明本文提出的CORS系统站址测试数据处理方法能够较客观地反映基准站的观测...     

海洋工程岩土工程勘察施工及其影响因素

随着经济的发展,我国近年来在造船、石油化工、码头等海洋工程方面发展迅速,与之相关的岩土工程勘察工作就显得尤为重要。本文对海洋工程岩土工程勘察的前期准备及施工过程进行了详细的阐述,并列举了影响海上正常钻探施工的因素及海洋钻探时的突发情况,结合自己的工作经验对钻探时遇到的突发情况提出了处理对策。     

工业坐标测量机器人定位误差补偿技术

由通用工业机器人和视觉传感器组成的柔性坐标测量系统是视觉检测技术在工业在线测量领域的重要应用。工业机器人的机械结构和控制过程复杂,因此其定位误差成为影响系统测量精度的最主要因素,但可以通过修正连杆参数的方式加以补偿。以MD-H运动学模型为基础,建立机器人工具中心点(Tool center point,TCP)的基于相对定位精度的定位误差补偿模型,避免坐标在不同坐标系转换过程中产生精度损失。对与机器人测量姿态有关的柔度误差进行针对性补偿,通过建立柔性关节的弹性扭簧模型,将柔度误差分解为外加负载柔度误差和机械臂自重柔度误差分别进行补偿。标定过程中使用激光跟踪仪作为外部高精度测量设备,只需在单点测量模式下就能实现对TCP的三维坐标采集,大大简化数据采集过程。经过补偿后,标定点处的方均根误差由之前的1.230 2 mm降至0.428 8 mm,验证点处的则由0.723 6 mm降至0.505 4 mm。     

工业遗产的保护与再生 从国棉十七厂到上海国际时尚中心

上海国棉十七厂改造项目借鉴了欧洲建筑遗产保护和改造的理论及手法,以充分体现工业建筑遗产的结构美和空间魅力为出发点,强调园区公共空间的完整和多样性,改造后将成为上海国际时尚中心。单体改造根据不同情况分别运用体现原貌、新旧结合、新旧对比等手法,"为建筑遗产吹入生命的气息"。