A metaheuristic approach for efficient and effective sketch-to-metric map alignment

Sketching as a natural mode for human communication and creative processes presents opportunities for improving human–computer interaction in geospatial information systems. However, to use a sketch map as user input, it must be localized within the underlying spatial data set of the information system, the base metric map. This can be achieved by a matching process called qualitative map alignment in which qualitative spatial representations of the two input maps are used to establish correspondences between each sketched object and one or more objects in the metric map. The challenge is that, to the best of our knowledge, no method for matching qualitative spatial representations suggested so far is applicable in realistic scenarios due to excessively long runtimes, incorrect algorithm design or the inability to use more than one spatial aspect at a time. We address these challenges with a metaheuristic algorithm which uses novel data structures to match qualitative spatial representations of a pair of maps. We present the design, data structures and performance evaluation of the algorithm using real-world sketch and metric maps as well as on synthetic data. Our algorithm is novel in two main aspects. Firstly, it employs a novel system of matrices known as local compatibility matrices, which facilitate the computation of estimates for the future size of a partial alignment and allow several types of constraints to be used at the same time. Secondly, the heuristic it computes has a higher accuracy than the state-of-the-art heuristic for this task, yet requires less computation. Our algorithm is also a general method for matching labelled graphs, a special case of which is the one involving complete graphs whose edges are labelled with spatial relations. The results of our evaluation demonstrate practical runtime performance and high solution quality.     

GNSS互操作若干问题

GNSS兼容与互操作是国际卫星导航领域的热点议题,也是用户实现多系统融合导航必须具备的条件。本文首先介绍了兼容与互操作的基本概念;简要分析了多GNSS系统互操作的基本趋势及GNSS4大核心系统信号互操作的现状;分析了现有北斗卫星导航系统(BDS)在信号互操作方面存在的问题,指出其对用户接收机制造商和多GNSS用户的影响;分析了坐标基准和坐标框架在互操作方面存在的问题及其可能带来的影响,指出坐标系统的实现、维持甚至更新策略带来的误差都可能给多GNSS互操作及导航定位结果带来影响;讨论了时间基准互操作存在的问题,以及可能的解决措施。最后归纳了本文的主要结论。     

深层搅拌桩弥补钻孔灌注桩承载力不足的尝试

针对某工程钻孔灌注桩的单桩进行静、动试验,对单桩极限承载力不能满足设计要求进行了分析。提出了用柔性深层搅拌桩弥补刚性灌注桩承载力不足的处理措施,对刚、柔性桩受力和变形协调性进行了分析,并使二者共同作用。处理结果表明：这种方法既经济,又便于施工,能完全达到设计要求,对类似地基事故处理具有参考作用。     

内蒙古地质地球化学分区及地球化学成矿预测

通过内蒙古表生环境中元素相容性排序检验,认为1∶20区域化探普查成果能提供原生环境中各类地质信息,尤其是普查找矿信息。区域化探元素测试结果存在系统误差,通过数据调平处理,保证了化探数据的质量。ln(wCr×wNi×wCo)等图件提供的信息,可作为划分地质地球化学分区的主要依据之一,对基础地质研究有参考价值。在此基础上初步圈定了元素地球化学成矿预测区,为内蒙古自治区提供了有价值的普查找矿信息。     

舰载直升机灯光助降系统电磁兼容性设计

根据直升机起飞、着舰时所需的助降灯光使用要求，考虑电磁兼容性标准，详细介绍了灯光助降系统的主机板、电源板、驱动电路、故障检测电路等硬件设计过程。     

海洋功能区划符合性判别方法初探——以港口功能区为例

借鉴国外用海兼容性和土地使用兼容性,分析了海洋功能区划符合性内涵,基奉原则,并以港口功能区为例,分析了港口用海对海洋环境的影响,建立了港口功能特征指标,以及港口功能区与海域使用之 间对照表.通过搭建起海域使用和海洋功能区划之间的桥梁,更好地为海域使用审批管理提供技术支持.     

GPS控制网起算点精度的检核方法

结合实际经验,阐述了起算点精度对GPS控制网兼容的重要性,介绍了几种检核起算点精度的有效方法。     

浅析地籍缮证图文的兼容

PDF栅格图的成功开发,在地籍总登记网络上,整合了原有的土地登记系统和测绘基础信息数据系统,实现两个业务系统的相互衔接,使得各项业务管理从＂自成体系,条块分隔＂的现状中解放出来,实现地籍发证图文同步：＂一站式,零环节,无纸化＂,办证期限＂归零＂。     

Efficacy of rights-based management of small pelagic fish within an ecosystems approach to fisheries in South Africa

South Africa's small pelagics fishery is moving towards a management strategy using an ecosystem approach to fisheries (EAF), with rights-based management (RBM) as the key rights allocation system. While EAF strives to balance between, among others, ecological and social-economic objectives, RBM is driving the sector towards economic efficiency. Within EAF itself, there are still underlying mismatches between the two top objectives, ‘human wellbeing’ and ‘ecological wellbeing’, in effect requiring a better balance between these objectives than there is currently. For example, fishers do not believe they should be competing with marine mammals and birds for allocation of the resource, yet this is one of the primary trade-offs that have to be made when setting the annual total allowable catches (TACs) under EAF. A balance between the two objectives could be achieved through acceptable trade-offs between them among all stakeholders within inclusive governance. Implementation of RBM has had both positive and negative effects on the objectives for EAF. Of concern are the negative effects of RBM on human wellbeing. For example, fishers feel that RBM has weakened their bargaining position, thereby reducing their benefits. In addition, RBM has resulted in job losses and insecurity of employment within the fisheries sector. The most affected have been the most vulnerable — the low level workers — who ought to be the key beneficiaries of RBM. Thus prioritising and protecting vulnerable groups and fishing communities need careful consideration when creating RBM, even in the context of EAF. Rights-based management has also had negative effects on ecological wellbeing through practices such as increased dumping and ‘high grading’ as part of industry's drive for increased efficiency under RBM. Whereas scientists believe that variability is largely due to environmental conditions, fishers strongly feel that dumping, high grading and high fishing pressure are the main factors. One of the positive aspects of RBM has been improved understanding among rights-holders and fishers of the need to consider other organisms in the TAC and to protect these through establishment of marine protected areas, island perimeter closures and limiting bycatch, thereby impacting positively on ecological wellbeing.     

具备兼容性的在线坐标转换系统设计

介绍了区域CORS系统地方坐标转换参数保密运用的常规方法,提出了通过网络实时进行在线坐标转换的方法;通过合理设计软件接口及公开数据通信协议,解决了各仪器厂家的手簿软件兼容问题;并通过实例验证了方法的可行性。