结合SVM与图匹配的车载激光点云道路标线识别

本文提出一种基于SVM与图匹配相结合的车载激光点云道路标线识别方法。该方法基于标线点云分割对象,利用Hu不变矩、实心形状上下文（SSC）、最小外包矩形（MBR）面积和延展度构建形状特征向量,采用SVM进行道路标线粗分类。针对粗分类结果,构建能够精确描述空间语义信息（如局部区域内标线间的排列、方向、距离）的图结构,通过图匹配方法优化粗分类结果,完成直行箭头、人行横道预告标识线、单向转向箭头、双向转向箭头、虚线型标线、斑马线共六类道路标线的精确识别。本文实验采用4份不同场景车载激光点云数据,实验结果中6类标线分类的准确率分别达100%、100%、94.12%、100%、94.94 %、99.25%,召回率分别达100%、100%、88.89%、100%、98.21%、99.00%,F₁-Measure值分别达100%、100%、91.43%、100%、96.59%、99.12%。结果表明,本文方法能实现多类标线对象的精确识别,并对形状相似标线（如直行箭头、虚线型标线与斑马线）的区分具有较强稳健性。     

长期演进项目中基于移动白组织网络的虚拟多输入多输出用户配对算法研究

在长期演进项目的虚拟多输入多输出系统中,为了保证用户公平性的同时得到更大系统容量,在分析移动自组织网络和虚拟多输入多输出系统模型的基础上,提出了一种长期演进项目中基于移动自组织网络的虚拟多输入多输出配对算法。仿真结果表明,该算法得到的系统吞吐量是单输入多输出系统的3倍多,是随机配对策略的2．5倍,相比正交配对策略也平均提高了20％。同时在用户的公平性方面,还保证了低吞吐量用户的公平性。     

基于P2P和QoS的移动GIS地图服务模型研究

介绍了移动GIS地图服务应用发展及趋势;研究了移动GIS地图服务中对等网络和地图服务质量控制机制的构建方法;基于P2P技术和QoS技术,针对移动GIS地图服务应用中存在的一些弊病,提出了四种服务模型：数据分层分块模型、地图服务匹配模型、数据缓存下载模型和地图数据传输模型,这些模型对于移动GIS地图服务应用中理论研究和技术开发具有较高的参考价值和借鉴意义。     

Global Landscapes: Teaching Globalization through Responsive Mobile Map Design

This article reports on the design and evaluation of Global Madison, a mobile map designed to support teaching and learning about globalization using Madison, Wisconsin, as a situated classroom. Our experience of place increasingly is mediated by mobile devices, opening new opportunities and challenges for research, industry, and education. Despite this rising popularity, few guidelines exist for creating and using mobile maps. Following tenets of user-centered design studies, we conducted two mixed-method evaluations of Global Madison to improve the tool and generate design insights that are potentially transferable to similar mobile mapping contexts: 244 students participated in an online survey after completing the tour and eighteen students were observed in the field. The evaluations generated new design considerations for mobile maps supporting situated learning, include: focus on critical issues that might leave students stranded, append location-based services with traditional mapping, enforce cognitive association between map and landscape, supply a consistent feed of information for new learners, encourage collaborative learning in the landscape, and promote student safety above all else.     

Lamprophyric intrusions of probable carbonatitic affinity from South Australia

Primary carbonate‐bearing lamprophyric rocks have been recognised in the Walloway Diapir, South Australia. Their petrography and trace‐element geochemistry indicates that they have carbonatitic affinities. The rocks are magnetic and can be detected by ground magnetometer surveys.     

The Differentiation of Point Symbols using Selected Visual Variables in the Mobile Augmented Reality System

On the basis of initial studies devoted to a better understanding of how the public user (a pedestrian in the city) perceives cartographic symbols in the mobile augmented reality system, we present an attempt to determine the threshold values of differentiation for three visual variables. The variables of size, transparency, and focus were implemented into image point symbols representing five types of objects. The set of symbols was designed in accordance with the rules of cartographic design taking into consideration an analysis of 19 professional tourist works. The symbols were presented on the screen of a mobile device in a system imitating the augmented reality system against four different backgrounds: white, a wall, and two typical urban landscapes. The results of an internet survey conducted using a tablet at four locations in Poznan (Poland) allowed us to determine the following: threshold differentiation values for the analysed variables, indication of the dependence on the type of background displayed on the mobile device in augmented reality, and the advantage of using a combination of visual variables.     

因特网及网络金融的服务定价问题

因特网的服务定僮和网络金融服务的定价问题，即是网络金融中的极具理论价值的问题，又是一个重要的实践问题，由于因特网自身的特殊性，其服务定价面临着困难，对此应提出定价策略，即削减“容量”，扩大“需求”；网络金融服务可采用提供免疫服务、各种优惠服务以及捆绑式销售服务这3种定价方式。     

采空区地表移动变形的时间影响参数

多层采空区多次复杂开采造成的累积沉降不能简单地用单一采空区地表移动变形模型作参照。对采空区的研究,时间影响参数是工程稳定性重点研究和考虑的问题。通过变形观测数据,得到一系列的时间影响参数C的数据点。C是随时间动态变化的,是相应的诸多条件综合影响的结果,拟合得到现时段的时间影响参数经验式。这对采空区今后的残余沉降的预测具有重要的实际意义。     

High-Resolution Measurement and Analysis of Visitor Experiences in Time and Space: The Case of Aalborg Zoo in Denmark

The notion of consumer and user experience has become dominant in our society in recent years, especially in relation to leisure activities. In this study we used the experience sampling method (ESM) data collection technique in Aalborg Zoo, Denmark, to understand the distribution of subjective experiences within this site. Visitors to the zoo were asked to send phone messages (SMS) about their subjective feelings in real time and to carry with them Global Positioning System (GPS) devices that recorded their movement. This method allowed us to geotag experiences of visitors throughout the zoo compound. The results indicate that the quality of experience of visitors varies both in time and in space. We conclude that there is a need to further explore the effect of place on experiences using repeat, high-resolution measurements. In this regard we believe that geographers, who have a long tradition of studying human–environment relations, have the tools to lead this type of exploration.     

A Manifesto on Mobile Computing in Geographic Education*

Abstract

Mobile, location-aware computing technology is widely available. In this article we sketch out a manifesto on mobile computing in geographic education (MoGeo) for consideration and debate within the geographic community. At the core of our argument is the idea that emerging mobile computing technologies will allow teachers to bring the classroom and pedagogic materials into the field, and that the resulting in situ educational experience will enhance learning by contextualizing the complex and abstract concepts that we teach. We provide a set of key principles that can guide the development of field experiences for students using these new technologies.