International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B6. Istanbul 2004
a existing route, basically used for freight traffic. The extension
is necessary to disburden another route, and to avoid the high-
frequented traffic agglomeration of Hannover.
There are lectures that give detailed information and an
introduction into the task. Thereby personal attendance is
compulsory. In terms of a blended-learning concept the
planning process will be exercised within the Virtual
Landscape. For this the basic geodata and the data of a
landscape framework plan are provided. The latter contains data
like different soil parameters, areas of groundwater
regeneration, water protection areas, flooding areas, areas of
biotope protection, areas of recreation, noise corridors etc.
Tools for exploring and analyzing data are supplied in the web-
based environment.
For visualization and analysis 2D and 3D-views are used. For
many applications, mainly in the field of analyzing, 2D-data is
not only reasonable but also better and more easy to handle.
However, for many other tasks perspective views are necessary.
Such tasks are e.g. visibility analysis, dissemination of noise or
visualization in planning processes (Petschek, P. & E. Lange,
2004).
3. IMPLEMENTATION
Due to the fact, that the project aims to establish a dynamic and
sustainable web-based E-Learning-Environment, a system
based on standards and Open-Source products is about to be
implemented.
The learning materials for basic knowledge consists of texts,
images, interactively explorable illustrations, animations and
tests. The websites are usual HTML, generated by PHP. For the
creation of assets PHP, JavaScript or Flash were used. Tests are
constructed as dynamic HTML-forms (based on PHP). At the
moment we are about to test the use of Macromedia's
Authorware for designing tests as well.
The inseparable engagement to a commercial Learning
Management System (LMS) has been avoided due to
dependencies and high amount of administration. However the
developed content may be put in a LMS at every time.
Even though Learning Management Systems offer a lot of
reasonable features, those functions did not seem as necessary
for the application in our blended-learning scenario as to
legitimate the high administration effort.
3.1 Course Material and didactic issues
The developed environment in this project is fit out with a lot of
features to make the learning- and communication process
comfortable, such as:
clear arrangement of courses and units,
linear navigation through the material,
possibility to skip between the tasks according to
personal knowledge and interest,
tests to check progress,
references to sources and for further reading -
individually assigned to every website,
generation of personal reference list,
generation of personal print version in PDF-format of
chosen sites,
contact to a support-person via e-mail.
The materials are build based on common rules for ergonomic
internet work (Buchholz, G.A., 2003; Nielsen, J. 1997; Nielsen,
J., 1999), These rules take into account, that reading in front of
a screen is different than reading a paper article in terms of
exhaustion, amount of accessible information and therefore
style of reading.
Some of those rules are listed in table 1.
Concern Rule
avoidance of
exhaustion of
eyes
use of light background and dark letters to
provide contrast
avoidance of completely white screen as a
background due to blinding effects
use of font size at least 10 —14 pt.
use of fonts without serifs, such as Verdana,
Monaco, Geneva or New York to avoid squiggly
fonts
avoidance of italic fonts
provision of
better
orientation
within the text
avoidance of complete words written in capitals
for better cognition of distinct words
avoidance of underscores when text should not
be marked as a link
highlighting of keywords to support recognition
of important paragraphs due to the fact that an
internet user is rather scanning the text than
reading it
avoidance of justification of paragraphs to allow
for orientation when reading
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assurance of
meaningful
outline of
internet-texts
inclusion of strong meta-contents, such as
headlines, subtitles, labels etc.)
order of text in the way that the important
message comes first (and verbose introductions
are avoided)
construction of effective texts, e.g. by using
prompts, avoiding exuberant use of adjectives
and putting further information behind the links
taking in mind that people is able to memorize
approx. 7 units (e.g. prompts) for a distinct fact
(e.g. not listing lots of prompts)
provision of further reading and links at the end
of the text
support of - promotion of multi-coding, e.g. application of
cognition and text and graphics for providing information in
memorizing different ways
promotion of multi-modality, e.g. graphic
and acoustic signals to allow cognition
the content
through different senses
Table 1: Rules for Creation of Ergonomic Internet Documents
(p. Buchholz, G.A... 2003. Nielsen, J.. 1997.
Nielsen, J., 1999)
3.2 Technical issues implementing the Virtual Landscape
As illustrated in Figure 1 the Virtual Landscape is laid on the
top of the course content. In most cases it may be directly
accessed from the learning materials. Depending on a special
task dealt in the materials, a distinct view upon the landscape
will be opened. When carrying out a map exercise for planning
tasks, e.g. data of sanctuaries are provided. Analysis of soil
erosion potentials requires e.g. data of soil type, soil texture,
description of soil horizons or precipitation.
The infrastructure “behind” the Virtual Landscape is based on a
system shown in Figure 2. It has to fulfil the following basic
requirements:
allowing easy data access on possibly distributed data
sets
visualization of data in 2D
visualization of data in 3D
basic analysis tools in 2D (and 3D)
An architecture, according to the OGC-conform visualisation
process — described by Cuthbert’s Portrayal Model (cp. Fig. 3)
— was set up (cp. May et al., 2003; Fitzke, J. & K. Greve, 2002).
