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RESEARCH ON DYNAMIC SYMBOL BASE
Yang ping ab , Tang Xinming ab , Wang Shengxiao c , Lei Bing b ,Wang Huibing b
a School of Resource and Environment Science, Wuhan University, 129 Luoyu Road, Wuhan 430079, China -
yangping_whu@163.com; b Chinese Academy of Surveying and Mapping, 16 Beitaiping Road, Beijing 100039 -
tang@casm.ac.cn ; c Shenhua Remote Sensing & Geo-Engineering Company LTD, Beijing 100085,China-
shengxiao.w@gmail.com; leibing@casm.ac.cn; wanghb@casm.ac.cn
KEY WORDS: Spatio-temporal Database, Classification of Spatio-temporal Process, Dynamic symbol base, Dynamic
Visualization
ABSTRACT:
As efforts grow to develop spatio-temporal database systems and temporal geographic information systems that are capable of
conveying how geographic phenomena change, it is important to associate the spatio-temporal process with a vivid representation.
The paper propose a way for visualization base on dynamic symbol base, by which represent the spatio-temporal process in a more
vivid and visually way. The paper proposes a new classification of spatio-temporal process, which builds a fundamental basis for
the representation of dynamic phenomena. Dynamic visual variable of dynamic symbol for the display of changing spatial-temporal
objectives will be discussed, a framework will be designed and implemented for the dynamic visualization.
1. INTRODUCTION
1.1 Dynamic Visualization and Animated Cartography
Spatiotemporal data can be graphically represented in many
ways. Vasiliev (1997) proposed a framework for graphic
representation in static maps; Andrienko et al. (2003) attempted
to do the same in an exploratory context, focusing on
interactive and dynamic visualization of spatio-temporal data.
Foundation for the visualization formalization was laid by
Bertin in 1967 (see Bertin, 1974). His semiological framework
has been further elaborated and extended. Among the main
developments in the visual domain (see alsq Schlichtmann,
1999) is research on effects of combinations of variables (e.g.
Spiess, 1970). Morrison (1974) and MacEachren (1994a, 1995)
have argued that the variables colour (including saturation) and
texture are composites rather than primitives, and they defined
the different components.
Furthermore, new variables such as transparency and fuzziness
or crispness of symbol edges have been distinguished and
applied to represent characteristics of data and of metadata
(MacEachren, 1994a; van der Wei et al., 1994). Adaptations to
Bertin’s way of linking the variables to data have been
suggested as well (e.g. Geels, 1987; MacEachren, 1995;
Morrison, 1974). Kraak (1988) investigated depth cues, i.e.
variables that can be used to simulate the third dimension on a
2-D surface, while DiBiase et. al. (1992) and MacEachren
(1994b) proposed dynamic variables for animated
representations, together with suggestions for their use.
Characteristics of geographic data can also be represented by
signs or signals for modes of perception other than sight.
Vasconcellos (1993) made an attempt to define tactile
equivalents of Bertin’s graphic variables for visually disabled
people. More recently, Griffin (1999) added kinaesthetic
variables (e.g. resistance, friction) for application in fully
immersive Virtual Environments.Barend Kobben described
preliminary tests for evaluating the perceptual properties of
dynamic visual variables. By the comparison of six kind
dynamic visual variables, included moment, duration,
frequency, order, rate of change and synchronization, they gave
out that dynamic visual variables would only render favorable
results in the use of cartographic animations.
These developments show that the framework for the
representation of geodata by perceptual variables, originally
founded by Bertin, is a dynamic construct that is still evolving
(Blok, 1998, Fairbaim et al., 2001; MacEachren, 2001).
Important reasons for ongoing developments are increasing
insight and progress in technological advancements. It is clear
that the representation framework is not a fixed construct; it
will be further extended and adapted. Blok developed the
framework by integrating the former visual variables into four
categories: moment of display, order, duration, frequency, gave
out the relationships between the dynamic visualization
variables, provided interactions options from a design
perspective, made the utilization of the variables from a user
perspective, and tested the effects of the using interactions of
various dynamic visualization variables.( blok,2005).
Such as we know, Amounts of work have been done on the
evolving of the Bertin’s framework, but more should be done
for further research. The goal of this paper is to propose a new
framework which can visualize the spatio-temporal processes
refer to each classification of temporal phenomena. By the
utilizing of dynamic symbol base, a methodology for dynamic
visualization of changing geographic data will be carried out.
2. CLASSIFICATION OF SPATIO-TEMPORAL
PROCESS
2.1 Taxonomy of STP ( Spatio-temporal process)
Various models of change have been developed by
mathematicians, geographers, philosophers, and computer
scientists. Kathleen Hornsby presented an approach to spatio-
