多模型协同下的城郊地区DEM构建方法研究

人类活动对地表的改造使其呈现形态多样化、不连续等特征,此时传统的DEM构建方法难以满足这些区域DEM精度要求。为此,本文提出了一种多模型协同构建DEM的思路,首先按照形态特征和语义信息对地形进行分类,然后对不同类型的地形区域,选择、设计适宜的方法分别进行DEM构建,最后将不同区域构建DEM结果融合拼接形成区域完整的DEM结果。本文选择江苏省南京市城市郊区某区域为实验区,以1:500比例尺地形图为基本数据源进行DEM构建实验。实验结果表明,与传统经典DEM构建方法相比,本文提出的多模型协同的DEM构建方法能够有效表达实验区域不同的地形特征,特别是对于人工改造的地形(如道路、边坡等区域),本文方法构建的DEM其形态精度优势显著;同时,基于验证点法的高程精度分析结果表明,本文方法构建DEM的高程精度亦优于传统DEM构建方法,特别是对于一些形态规则而高程信息相对稀少的区域,以边坡区域为例,经典DEM构建法平均误差均超过5 m,而本文构建结果平均误差为0.26 m,精度优势非常明显。研究表明本文提出的多模型协同的DEM构建方法适用于人类活动改造或显著影响的区域的DEM构建。     

中国县域交通优势度与农村发展的空间协同性及影响机制解析

利用综合评价、耦合协调度、空间滞后模型（SLR）等模型,对2000~2010年的中国分县农村综合发展水平及2010年的分县道路交通优势度进行综合测度,解析其两者的空间耦合协同特征,并探索道路交通对农村发展的影响机制。结果表明：① 2000~2010年,中国分县的农村综合发展水平的东、中、西差异格局未突破,农村综合发展水平整体提升了33.20%。东部地区的农村发展进入优化整合提升阶段,中、西部地区在政策、产业转移、城镇化、工业化等驱动下农村综合水平提升较快,乡村多维空间历经转型重构。② 2010年,县域道路交通优势度呈现出典型的“点-轴”的地域结构特征,存在东、中、西部和交通枢纽中心地与外围地区之间的地域差异,其与农村发展水平耦合协同性整体较差,处于轻度失调以下状态占县（区）总数的88.25%,西部地区协调度普遍低于0.40,交通发展与农村发展协同性较好地域集中于东部沿海地域和道路交通优势极核及轴带的县（区）。 ③ 道路交通等级、密度、可介入性等影响农村综合发展。道路密度对农村发展正向影响较大,国道、省道、县道沿途邻近可进入性强,对农村综合发展有积极促进作用;高速公路和铁路有景观生态学“廓道”性质,空间上起连通作用,结构的不可穿越性,封闭性影响可介入性,高速公路的出入口和火车站空间布局对农村发展影响显得尤为重要。④ 地级市交通中心地对农村发展带动影响明显,大城市的强聚集能力易促成周边县区的农村发展“灯下黑”的地域结构特征。道路交通设施建设的等级、阶段对农村发展的传导效应及区域交通建设的超前或滞后的科学判断核心理论,将是人文经济地理学及乡村地理学亟待关注的重要领域。     

基于多视图协同的时空数据可视分析方法

针对时空数据可视分析中存在的问题,提出了由可视分析模型(VAM)和交互协同模型(ICM)组成的多视图协同可视分析模型,将可视分析过程划分为数据变换、数据分析、可视映射和可视绘制4个过程;以可视分析过程中的参数作为协同主题,利用观察者模式,实现关联视图在交互过程中的协同一致;设计了Web环境下,基于"图数协同"和"图图协同"交互模式的多视图协同可视分析架构;构建了犯罪时空数据可视分析原型系统,并利用系统分析了福州市扒窃案的时空分布规律,对涉案价值较高的扒窃案进行了犯罪模式分析。     

Developing a Web-based flood forecasting system for reservoirs with J2EE / Développement sur Internet avec J2EE d’un système de prévision de crue pour barrages

Abstract

Abstract A flood forecasting system is a crucial component in flood mitigation. For certain important large-scale reservoirs, cooperation and communication among federal, state, and local stakeholders are required when heavy flood events are encountered. The Web-based environment is emerging as a very important development and delivery platform for real-time flood forecasting systems. In this paper, the findings of a case study are presented of the development of a Web-based flood forecasting system for reservoirs using Java 2 platform Enterprise Edition (J2EE). J2EE of Sun Microsystems is chosen as the development solution for the Web-based flood forecasting system, Weblogic 6.0 of BEA as the container provider, and JBuilder 7.0 of Borland as the development tool. One of the key objectives in this project is to establish a collaborative platform for flood forecasting via Web technology in order to render hydrological models and data available to stakeholders and experts involved and thus offer an efficient medium for transferring and sharing information, knowledge and experiences among them. Compared with general Web-based query systems and traditional flood forecasting systems, the Web-based flood forecasting system is more focused on the on-line analysis of model-based forecasting of floods and provides opportunities for improving the transfer of information and knowledge from the hydrological scientists and managers to decision makers. Finally, a prototype system is used to demonstrate the system application.     

时空协同的精准农业遥感研究

高分辨率遥感对地观测为我们从空间与时间2个维度客观反演地表格局—过程提供了有效的技术支撑。本文遵循时空协同的研究思路,基于高分辨率遥感影像,开展了农业遥感领域2个典型的问题研究：① 提出了一种基于影像视觉特征的耕地分区分层提取方法,该方法在利用DEM数据进行分区的基础上,根据不同区域内耕地所呈现的几何特征和纹理特征差异,分别设计了不同的耕地提取模型;② 构建了一种地块尺度的作物生长参数反演方法,方法以地块为基本单元,在空间、时间及属性组合约束下进行作物理化参数反演。本研究以贵州省安顺市西秀区和广西扶绥县耕地提取进行了耕地地块提取示范,以扶绥县进行了基于耕地地块和中空间分辨率时间序列遥感数据的甘蔗叶面积指数反演。其中,对于安顺市西秀区的耕地地块提取结果而言,形态精度（IoU）大于0.7的地块超过60%,规则耕地、梯田以及林草地等的类型精度均超过了80%;对于扶绥县甘蔗叶面积指数反演的结果而言,其结果可以较为精确地反映出基地甘蔗与非基地甘蔗的差异,基地甘蔗在品质上要优于非基地甘蔗。西南山地区的耕地形态提取/类型判别和地块甘蔗叶面积指数应用验证均证明了方法的可行性。结果表明,协同使用多源高分辨率数据是实现精准农业遥感研究的有效途径。     

基于区块链的多方协作安全身份认证机制研究

信息技术的快速发展使身份认证机制的安全性得到越来越广泛的关注.但现有的身份认证机制存在着隐私泄露等风险,这就要求设计出更加可靠的身份认证机制.本文利用区块链的去中心化、不可篡改等特性,设计出基于区块链的多方协作安全身份认证机制.在实现可靠身份认证的同时,保证信息的权威性,在一定程度上减少数据冗余,并提高身份认证效率,保证全面且准确的身份认证.最后实现支持多个数据服务商对身份信息进行加密签名,保护数据隐私,以及多方共享数据的身份认证系统.     

拖拉机驾驶机器人设计及人机协作方法研究

针对农用拖拉机智能化程度低,以及现有的人工智能水平尚无法完全实现自主驾驶控制拖拉机等问题,本文设计一种基于人机协作的拖拉机驾驶机器人.拖拉机驾驶机器人可以对拖拉机进行快速、无损、智能化升级,其结构由转向控制机械手、换挡机械手、旋耕机升降控制机械手和踏板控制机械腿等组成.通过研究人机协作的控制方法,提出了人机协作介入准则和基于转向电机电流反馈扭矩检测的人机协作模式切换方法,研制了原理样机验证拖拉机驾驶机器人的可行性和人机协作控制策略的有效性,对促进精准农业,提高现代农业智能化装备水平具有重要的现实意义.     

智慧规划下的协同编制信息资源平台研究

新兴技术的飞速发展不断改变着规划信息化的应用场景和模式,城市规划需要在工作模式、技术手段与组织方法等多方面进行信息化革新,才能适应城市化转型要求。本文通过对智慧规划的论述和大数据对规划方法影响的分析,并结合广州在总体规划协同编制的信息化实践,提出了时空信息聚合、实时汇聚、智能共享的信息协同解决方案,实现了规划师之间、部门之间的纵向及横向协同,不同层级规划的紧密衔接,汇集多来源、各阶段的工作成果,建设规划编制信息的资源池。     

Overcoming remoteness: the necessity of air travel in Australian universities

ABSTRACT

Air travel has become central to Australian academic practice, with flying increasingly seen as crucial to the progression of successful academic careers. This paper seeks to understand why academic air travel has come to be perceived as so necessary, particularly given its significant environmental, social, and economic implications. Drawing on the mobilities paradigm and social practice theory, we seek to understand how air travel practices are a key part of contemporary academic careers. We conducted an online survey of 301 academics and 24 in depth semi-structured interviews to understand academic air travel in Australia, finding that it is seen as a means to connect and collaborate within and between academic communities, and to counteract the effects of ‘remoteness'. This remoteness is experienced domestically and internationally, by Australian academics who feel they must travel to perceived centres of knowledge production to further their careers. Academics often frame their ‘need' for connections as necessarily involving physical co-presence. Air travel offers career benefits for those who can take advantage of it, and corresponding drawbacks for those ‘stuck on the ground’. We conclude by discussing the need for valuing localised forms of collaboration as markers of success, and developing imaginative alternatives to academic flying.     

Factors Influencing Adoption and Implementation of Conservation Development Ordinances in Rural United States

Conservation Development (CD) is a land-use tool to reduce the impacts of development on natural resources, yetthe use of CD is highly variable. We used a collaborative conservation model to examine factors influencing adoption and implementation to improve the future application of CD. We interviewed 2–3 individuals including planners, board members, and developers (n?=?46) from 16 rural communities in the intermountain west and northeast U.S. Motivations to preserve rural character or comply with state statutes drove adoption. Greater capacity such as outside expertise, model regulations, and iterative revisions of ordinances was associated with stronger ordinances. Adoption processes including ample dialog across diverse constituents, especially those overseeing subdivision development, facilitated higher rates of implementation. Concerns over open space management, lack of successful CD examples, and inexperience with CD posed barriers to implementation. Understanding social context revealed the strengths and shortcomings of CD and provided guidance for strategically engaging communities in private lands conservation.