Designing Web-Based Educational Virtual Reality Environments - Teaching through Multi-User Virtual Environments - page 159

merse the user into the experiment. The students
will be able to observe the execution of the real
experiment through the camera as well through
the 3-D visualization. Besides the possibility of
conducting the real experiment, the user will be
additionally able to perform a simulation of the
experiment in order to compare the theoretical
results with the corresponding real results.
A similar application for the execution of
experiments through internet is Virtual Control
Lab (VCLab, 2002). VCLab has been originally
developed as a tool to support students in control
system design using professional simulations
of automation processes. Because of its generic
character, there are no restrictions to make use of
it also in other scientific domains. VCLab uses
a 3D virtual user environment to recreate and to
visualize experimenting plants. One can interact
with a displayed scene in a similar fashion like
with real devices. The dynamical behavior of
the plant is generated by a simulator driven by
simulation models.
Another application for distance education is
VirLab system (VirLab, 1999) which developed
at Hagen University in Germany. The application
concerns the navigation of a vehicle. The user
inserts the data of movement and then he can
watch the experiment through a video or a 3D
simulation, while he is also able to communicate
with the other connected users. On the other hand,
an educational application was developed within
DEVRL (DEVRL, 1995) research project. Spe-
cifically, virtual places were developed such as a
virtual classroom, where students can participate
in a number of collaborative procedures using the
potentials of virtual reality technology. Within
this virtual environment, users can experiment
with numerous simulations dealing with physical
phenomena, such as gravity, or execute experi-
ments, which are difficult to be contacted in a real
laboratory. Furthermore, a large number of virtual
reality applications supporting collaborative learn-
ing have been developed. To mention a few: EVE
(Bouras et al, 2003), INVITE (Bouras et al, 2001)

and CLEV-R (McArdle et al, 2004). These systems
provide multi-user virtual environments, which
enhance learning, collaboration and dissemination
of knowledge using multimedia content for the
distance education of university students.
Another, huge category of virtual reality educa-
tional environments concerns applications focus-
ing on the teaching of mathematics (Pasqualotti et
al, 2002), physics (Esparrachiari, 2005), computer
graphics (Buraga et al, 2002) etc, while there is
a keen research interest for the development of
chemical experiments simulations. Especially in
the case of chemistry, the potentials of virtual
reality technology can facilitate learning process
surpassing major restrictions characterizing tra-
ditional educational methods. Its primary objec-
tive is to provide highly realistic and believable
simulations of chemical procedures within a fully-
immersive, interactive and three-dimensional
virtual world. The educational benefit of these
applications is the active participation of students
in learning process, since researches have shown
that humans remember only 10% of what they
read, 20% of what they hear, but retain up to 90%
of what they learn through active participation
(Dale, 1969). Moreover, students can observe or
carry out virtual chemical experiments, which are
either difficult or even impossible to be performed
in a physical laboratory e.g. high-speed chemical
activities that do not allow observation and reli-
able measurement of results (explosions, issues of
chemical kinetics etc), extremely slow or complex
chemical processes, experiments involving health
risks for students and teachers (e.g. radiations),
processes requiring expensive consumables or
devices not available in a conventional laboratory
etc (Kalogeropoulos & Karatzas, 2002).
Recently a lot of research efforts have been
made aiming to take advantage of the potentials
that virtual reality and Web technologies offer
at chemistry instruction, such as Lab 3D (Lab
3D, 2002), which deal with hygiene, safety and
biochemistry issues respectively. Furthermore, in
(Schofield et al, 2004) a virtual reality application