地图与动画的结合与发展

地图动画是一种新型的可视化表现方式。本文回顾了地图动画的发展历史。探讨了地图动画的信息含量,总结了地图动画的有关研究内容,最后以SARS疫情为数据源,制作了关于疫情变化的动态地图,收到较好的视觉效果。     

浅析动画效果地图的公开表示

公开地图的表示关乎国家安全、领土完整、民族尊严,具有严肃的政治性、严密的科学性和严格的法定性。动画效果地图是大众喜闻乐见而又十分有效的信息传播载体。但在公开表示方面存在盲区,是"问题地图"的高发区,可能造成严重的不良影响。本文总结了动画效果地图的常见类型、高发问题及成因,提出了动画效果地图表示方法建议,明确了地图底图和动画效果都要符合公开地图表示有关要求,对动画效果地图的制作和公开使用具有一定的指导性和启发性。     

Animated Maps of Aggregate Data: Conceptual and Practical Problems

Predictions of the 1960s about the computer's potential to change cartography are finally being fulfilled. Dynamic maps for vehicle navigation, interactive cartographic/statistical tools, and map animation are being investigated actively. As these new environments for mapping become available, we must reevaluate past questions about transformations from reality to data and data to map. In this paper, we consider these transformation questions in the context of statistical map animation. The issues discussed were raised in producing a “map movie” depicting the spread of acquired immune deficiency syndrome (AIDS) over time. Jenks' data model concept is used as the basis for a typology of data models representing phenomena typically depicted by enumeration unit data. The typology is then used to evaluate symbolization decisions for AIDS incidence maps. Implications for symbol selection imposed by dynamic rather than static maps are considered, as are technical issues involved in producing the animation on a microcomputer platform. A hybrid symbolization method that we have termed the “chorodot” is suggested as a way to meet the constraints on symbolization imposed by animation and to represent the appropriate data model for AIDS incidence.     

Assessing the Effectiveness of Dynamic Symbols in Cartographic Communication

Abstract

The age of the Internet poses new challenges to cartography. While cartographic animation has become a practical alternative, it is mostly used to depict both spatio-temporal and non-temporal changes. The paper concentrates on the use of dynamic symbols on a static base map. A visual test was carried out to obtain some perspectives about the cartographic communication of blinking point and line symbols. The results confirmed that dynamic symbols tended to attract the attention of the users in general and even in situations when the foreground–background contrasts were poor. Their effectiveness was more pronounced with symbols of a larger size but tended to diminish with an increasing number of blinking symbols. It was also observed that users were able to perceive differences in the frequency of flickering, particularly when the variation was large. The line animation method (marquee and grow-out) did not yield a substantial difference in visual responses in the case of blinking line symbols.     

3DSMAX在虚拟现实中的应用

随着虚拟现实技术的成熟发展,它已经作为一种产业逐步在各行各业得到应用,虚拟现实平台软件层出不穷,它们有一个共同的特点就是致力于更好地展现所创造虚拟环境的沉浸感、交互性、构想性,但3维模型、动画的构建还需要借助第三方软件来实现。3DSMAX是世界知名的3维建模、动画与渲染软件,绝大多数虚拟现实中3维模型和动画的制作是利用3DSMAX来实现的。本文结合校园虚拟现实的构建,探讨3DSMAX在虚拟现实构建中3维模型建立的方法和技巧。     

Scale-dependent representations of relief based on wavelet analysis

Automatic generalization of geographic information is the core of multi-scale representation of spatial data, but the scale-dependent generalization methods are far from abundant because of its extreme complicacy. This paper puts forward a new consistency model about scale-dependent representations of relief based on wavelet analysis, and discusses the thresholds in the model so as to acquire the continual representations of relief with different details between scales. The model not only meets the need of automatic generalization but also is scale-dependent completely. Some practical examples are given.     

Scale-Dependent Representations of Relief Based on Wavelet Analysis

Automatic generalization of geographic information is the core of multi-scale representation of spatial data,but the scale-depentation of spatial data but the scale-dependent generalization methods are far from abundant because of its extreme complicacy.This paperputs forward a new consistency model about scale-dependent representations of relief based on waveley analysis,and discusses the thresholds in the model so as to acquire the continual representations of relief with different details between scales.The model not only meets the need of automatic generalization but also is scale-dependent completely.Some practical examples are given.     

采用交替K-奇异值分解字典训练的图像超分辨率算法

采用稀疏表示的图像超分辨率算法中,双字典训练算法与字典的细节恢复能力相关,针对已有双字典训练算法使字典缺乏高频细节信息的特点,提出了一种交替K-奇异值分解字典训练算法。该算法分为训练和测试部分。在训练部分每次字典更新都采用奇异值分解所得到的向量对低高频样本块进行最佳低秩逼近,使得低高频样本块随着迭代次数的增加逐渐取得相同或者相似的稀疏表示系数。在测试过程中,测试低频样本块可以利用低频字典取得的稀疏表示系数与高频字典相乘得到高频细节信息。实验表明,与目前已有算法相比,该算法能够得到高频细节较丰富的图像,平均峰值信噪提高0.3 dB以上,结构相似度提高0.01左右。     

海洋岛屿制图综合原则的改进与实践

就海洋岛屿在地图上如何进行综合,尤其是岛屿岸线的概括和一直没有在地图上得到表示的潮差部分的地貌应如何表示,结合生产实践,给出了可以参考的方法。     

Fast Image‐Space Silhouette Extraction for Non‐Photorealistic Landscape Rendering

Landscape illustration, a core visualization technique for field geologists and geomorphologists, employs the parsimonious use of linework to represent surface structure in a straightforward and intuitive manner. Under the rubric of non‐photorealistic rendering (NPR), automated procedures in this vein render silhouettes and creases to represent, respectively, view‐dependent and view‐independent landscape features. This article presents two algorithms and implementations for rendering silhouettes from adaptive tessellations of point‐normal (PN) triangles at speeds approaching those suitable for animation. PN triangles use cubic polynomial models to provide a surface that appears smooth at any required resolution. The first algorithm, drawing on standard silhouette detection techniques in surface meshes, builds object space facet adjacencies and image space pixel adjacencies in the graphics pipeline following adaptive tessellation. The second makes exclusive use of image space analysis without referencing the underlying scene world geometry. Other than initial pre‐processing operations, recent advances in the OpenGL API allow implementations for both algorithms to be hosted entirely on the graphics processing unit (GPU), eliminating slowdowns through data transfer across the system memory bus. We show that both algorithms provide viable paths to real‐time animation of pen and ink style landscape illustrations but that the second demonstrates superior performance over the first.     

关于线状地理特征空间关系的自然语言描述的形式化表达

目前的地理信息系统都使用定量的方法存储和查询空间信息,不能反映人们的定性思维方式,因此它表达地理空间信息的能力受到限制。在关于空间关系的自然语言描述的调查的基础上,本文定义了一组能反映线状物体空间关系的度量指标,结合反映拓扑关系的定量指标,使用决策树的数据挖掘算法,对调查结果进行分析,形式化了描述空间关系的自然语言词汇,建立了模糊的自然语言表达和图形的几何特征之间的联系。自然语言形式化后得到的规则可用于空间关系的自然语言查询系统。     

虚拟人在国庆阅兵推演系统中的应用研究

本文简要介绍了虚拟人动画的控制实现方法;重点讨论了基于骨骼动画技术的虚拟军人动画在国庆阅兵推演系统中的应用和实现关键技术;初步探索三维场景中大数据量多目标绘制时提高虚拟军人动画渲染速度的方法.     

Evaluating Alternative Line Simplification Strategies for Multiple Representations of Cartographic Lines

Two basic strategies have been identified for handling multiple representations of line features in digital databases. Either a finite number of scale-dependent representations of cartographic lines can be explicitly stored, or a scale-independent database is generated from which subsequent scale representations can be extracted as needed. These two strategies parallel differences in hierarchical and non-hierarchical line simplification operators. Non-hierarchical line-simplification can produce the most geometrically accurate simplification at any scale, while hierarchical operators are often associated with scale-independent databases. In this research, hierarchical and non-hierarchical line simplification operators are evaluated by comparing both the points retained by these different algorithms and the overall quality of the graphic portrayal for sample lines of different complexity and at different scales. Visual inspection of the results did not reveal any discernable difference at any scale for any line. Subsequent numerical analyses shows some differences but overall little geometric quality is lost by using a hierarchical operator as opposed to a non-hierarchical one and given the greater flexibility of scale representations that is possible, hierarchical methods appear to be more satisfactory.     

Animation of Reliability in Computer-generated Dot Maps and Elevation Models

Visualization of reliability in spatial data has been the subject of considerable recent research activity. Animation has been suggested as one method to achieve this, and its application to various measures associated with class-area maps (classified satellite images and soil maps) has been discussed elsewhere. Animation is achieved by randomly selecting a location and then assigning it to a different map unit (cover or soil type) according to the information on the reliability associated with the original map or map units. In this article the same basic method is extended to mapping locational reliability in dot maps and surface error in a digital elevation model (DEM). In the former case, the dots, which are randomly located in the first place, are randomly relocated so that any meaningless positional information implicit in the location of the dots is lost while the meaningful information (the number of dots within a region) remains constant. In the DEM, animation uses a random field as an error surface, based upon the root mean squared error (RMSE). The amount of error at a location is constantly changed, giving no impression that the elevation is precisely known. The ability to vary the spatial autocorrelation within the error field provides a graphic illustration that the usual RMSE is not a sufficient method for the reporting of error in spatial databases. In both examples animation of reliability is believed to make a novel, but appropriate, use of the computer in cartography.     

Exhibiting the Exhibitors: Spatial Visualization for Heterogeneous Cinema Venue Data

Abstract

Cinema data is characteristically complex, heterogeneous and interlinked. Rather than relying on simple information retrieval techniques, researchers are increasingly turning to the creative exploration and reapplication of data in order to more fully explore the meaning of newly available and diverse data sets. In this context, the cinema historian becomes the creator of visual texts which can be assessed for both their interpretive insight and their aesthetic qualities. This paper presents four research projects that use different spatio-temporal visualization techniques to understand the industrial dynamics of post-war film exhibition and distribution in Australia. The research integrates work by a group of inter-disciplinary investigators into the effectiveness of techniques such as dendritic mapping, Circos circular visualizations, animation, cartogram mapping, and multivariate visualization for the study of cinema circuits and operations at a number of scales.     

Cybercity: Conception,technical supports and typical applications

In this paper,the concepts about the CyberCity and the corresponding technique supports and typical applications are introduced.As the pilot projects,the applications of CCGIS software in CyberShenzhen and CyberShanghai are also presented.At last,some of key technologies such as the reconstruction of three dimensional city model,vast amount of data integration and its real time application of 3D animation are discussed.     

BDS卫星端DCB不同表达对单点定位精度的影响

考虑到北斗卫星导航系统(BDS)的B1B2,B1B3及B2B3之间硬件延迟(DCB)值存在一个闭合差,分析BDS卫星端DCB改正公式不同表示方法在3种采样率下对定位精度的影响,分别进行了伪距定位和精密定位解算。结果表明,不同采样率的DCB改正后SPP下精度改善在m级,提高10%~80%;动态PPP下精度改善在dm~m级,提高50%~90%。改正公式的不同DCB表示方法对精度影响在cm量级,在SPP中可忽略该误差,动态PPP中建议取DCB改正均值作为最终改正值。     

A Conceptual Schema Language for the Management of Multiple Representations of Geographic Entities

Multiple representation of geographic information occurs when a real‐world entity is represented more than once in the same or different databases. This occurs frequently in practice, and it invariably results in the occurrence of inconsistencies among the different representations of the same entity. In this paper, we propose an approach to the modeling of multiple represented entities, which is based on the relationships among the entities and their representations. Central to our approach is the Multiple Representation Schema Language that, by intuitive and declarative means, is used to specify rules that match objects representing the same entity, maintain consistency among these representations, and restore consistency if necessary. The rules configure a Multiple Representation Management System, the aim of which is to manage multiple representations over a number of autonomous federated databases. We present a graphical and a lexical binding to the schema language. The graphical binding is built on an extension to the Unified Modeling Language and the Object Constraint Language. We demonstrate that it is possible to implement the constructs of the schema language in the object‐relational model of a commercial RDBMS.     

数码城市:概念、技术支撑和典型应用

首次系统全面地介绍了有关数码城市 (CyberCity)的概念、技术支撑和典型应用 ,并结合CCGIS软件的研究开发及其在深圳和上海两个城市的示范应用 ,讨论了建设数码城市所面临的若干关键技术问题     

Impacts of Spatial Partitioning in Hydroecological Models: Predicting Grassland Productivity with RHESSys

Environmental models constructed with a spatial domain require choices about the representation of space. Decisions in the adaptation of a spatial data model can have significant consequences on the ability to predict environmental function as a result of changes to levels of aggregation of input parameters and scaling issues in the processes being modelled. In some cases, it is possible to construct a systematic framework to evaluate the uncertainty in predictions using different spatial models; in other cases, the realm of possibilities plus the complexity of the environmental model in question may inhibit numeric uncertainty estimates. We demonstrate a range of potential spatial data models to parameterize a landscape‐level hydroecological model (RHESSys). The effects of data model choice are illustrated, both in terms of input parameter distributions and resulting ecophysiological predictions. Predicted productivity varied widely, as a function of both the number of modelling units, and of arbitrary decisions such as the origin of a raster grid. It is therefore important to use as much information about the modelled environment as possible. Combinations of adaptive methods to evaluate distributions of input data, plus knowledge of dominant controls of ecosystem processes, can help evaluate potential representations. In this case, variance‐based delineation of vegetation patches is shown to improve the ability to intelligently choose a patch distribution that minimizes the number of patches, while maintaining a degree of aggregation that does not overly bias the predictions.