THE INTERACTIVE DATA VISUALIZATION WITH Java 3D
M. Emoto, M. Shoji, S. Suzuki, S. Yamaguchi, NIFS, Toki, 509-5292 Japan
R. Muratsu, J. Narlo, M. Tamura, Y. Tanahashi, Nihon Sun Microsystems, Tokyo, 158-8633 Japan
Y. Teramachi, University of Industrial Technology, Sagamihara, 229-1196 JapanJ. Kariya, Yamaguchi University, Ube, 755-8611 Japan
H. Okumura, Matsusaka University, Matsusaka, 515-8511 Japan

Abstract
NIFS (National Institute for Fusion Science) isengaged in developing a real-time monitoring system fortheir LHD (Large Helical Device) experiments. Thesystem allows users to remotely participate in theexperiments. The monitoring system is utilizing Java
technology to accomplish these tasks. Some of the tasks
include the ability to monitor experiments in real-timeand data retrieval from remote stations. Also with thistechnology, an alarming system, as presented in thisconference, has been constructed to notify researchers bysome physical method (i.e. email, pager, etc...). The goalis an easily used and complete monitoring system thatcan be used from any browser. To achieve part of thisgoal, a graphical representation of the various aspects ofthe monitoring system is needed and is being developedwith Java 3D technology. By using Java 3D, integration
with the Java based monitoring system is easily andefficiently realized. Java 3D allows for a quick, easy, andinteractive interpretation of the vast amount of data andgeometry associated with the experiments. This allows
participants to efficiently analyze key aspects and toquickly identify malfunctioning parts or troublesome
areas in the experiment. From this aspect, we are
studying the Java, including Java 3D, technology and its
internet capability to carry on monitoring, data captureand data analysis of real-time LHD experiments withremote participation.

system has been studying and developing [2-4]. Thissystem uses the Internet and Java technologies, sotechnically researchers can monitor the sensor data andcan operate the ADC controller interactively while they
are outside of the control room. One of the advantages to
use Java is that it is OS independent, this means that one
can run the program on any operating system that
implements the JDK1.1 runtime environment. The otheradvantage is about the maintenance of the system.
Because the program is downloaded to the clients when
they connect to the servers, it is easy to upgrade theprogram. As the next step of this system, 3D graphics
feature was added. This feature enables researchers torecognize the phenomena easily and intuitively. This
paper shows the study of the temperature visualizing
system, which monitors the temperature of the vacuum
vessel. This helps the understanding the status of theplasma peripherals, such as magnetic distribution in thediverters.

2 COMPUTER SYSTEM AND GRAPHIC
MODELING

A /D1 INTRODUCTION
Large-scale experiment, such as accelerator
experiments or a nuclear fusion experiments produce
huge data. LHD was constructed and has been operating
in NIFS since the end of March, 1998 [1]. This is thelargest superconduction fusion experimental device.
Because LHD makes a complicate shape, a lot of sensors
are required to study various aspects of the plasma andthe machine operation. LHD experiment produces about
10MB data per one plasma discharge typically in present
time, and 10,000 shots per year will be achieved. In
addition to such a periodical measurements, thecontinuous monitoring is required to realize a stable
operation. To accomplish this task, the LHD monitoring

S un U ltra2(A /D server)

1 00 B ase T X

O p tical fib er

1 00 B ase T X

R A IDS un U ltra2(W W W ,R D B ,R M I server)

PC(C lient)Figure. 1: network configuration

S un U ltra 2(C lient)

application is shown in Fig.2, the sensors are represented
by the cube and superimposed on the vacuum vessel
model. These sensors are colored depending on themagnitude of the temperatures. The temperature isindicated by the graduation of the color, the higher thetemperature becomes it is colored by white, the lower thetemperature gets down, it is colored by blue. The color ofthe sensor is also used as the alarming system, and if themagnitude of the temperature excess the limit, the color
turns to red. The hardware and software used in thisapplication are listed in table 1.

3 EXAMPLE OF DATA VISUALIZATION

Table 1: system configuration
serverclient(WS) client(PC)CPU
Ultra Sparc Ultra Sparc Pentium II
166MHz ×2 166MHz×2 450MHz
×1
VIDEO
Creator 3D Matrox
Millenium
G200
OSSolaris 5.5.1 Solaris
MS5.5.1
WindowsNT4.0 SP4
JDK
1.1.6
1.2
1.2β
Java3D
1.1
1.1(OpenGL)DB
SybaseSystem 11JDBC
SybaseSybasedriverjConnectjConnect
5.0β
5.0β
The configuration of the LHD monitoring system isshown in Fig. 1. The A/D server acquires the data fromthe A/D converter, and it converts the raw signal data tophysical value. Both raw and physical data are delivered
to the all connected computers on the subnet using
multicast, and the HTTP server stores the received data.
The client applet can get the data from the HTTP server
by Java RMI (Remote Method Invocation). The clientside programs are written in Java language, and using
JDBC (Java DataBase Connectivity) they retrieve theinformation of the experimental instruments such as theamplifiers, the sensors, and the power suppliers from thedatabase server, on which the HTTP server also runs.
The 3D graphics application reads the geometricalinformation of the vacuum vessel from the file, anddisplays the vacuum vessel shape and the location of thesensors retrieved from the database. One output of thisFigure 3 plots the temperatures of the sensor during
NBI (Neutral Beam Injection) experiment. The vacuum
vessel was heated by the NBI, and the temperatures went
higher after the beam injection. The temperature
distribution of the vacuum vessel is the results of theenergy deposition of the NBI heated plasma. Figure 4
shows the temperature distribution before/after the NBI.
The temperatures higher than 29.0 °C were drawn byorange, and the temperatures lower than 28.75 °C weredrawn by dark blue. The temperatures between the above
two values were drawn by the neutral tints.
29.5
A-V/V-1A_LB A_Temp-001

29.25

Temperature (K)Figure 2: temperature distribution
The temperature distribution is superimposed by thetranslucent geometry of the vacuum vessel .

A-V/V-1B_LB_-U145A_Temp002

29

28.75
28.5

28.25
28

NBI (15:53:00)
27.75
27.5
15:30:00

15:45:00

16:00:00

16:15:00

16:30:00

Figure 3: temperatures of the sensors
The temperatures became high after the NBI.

4 DISCUSSION AND CONCLUSION
Through the development of this application, Java 3D
is a useful 3D-visualisation tool. This system uses 22,000
triangles for the vacuum vessel geometry, and retrieves
100 values of the sensors from the RMI server every fiveseconds, and redraws them by the color depending on
their values. Because today’s rapid progress of CPU andgraphics cards, even a mid-range class PC (Pentium II300MHz, with 3D accelerator) has enough power to run
the 3D applications written in Java.
In the Internet world, VRML [5] is widely used as athree-dimensional description language more than Java
3D. The concepts of both languages are similar, but there
are significant differences, and VRML has someTable 2: Comparison with Other Language
Java 3DVRML
C/C++( OpenGL,Direct 3D,etc.)
NOOS
YES
Independence (Win32 andSolaris
inthe presenttime)
Tools
FEW
MANY
MANY
Performance
FASTESTRun on WEB
YES
YESNO
Browsers
ActualYESNO
YES
Programming
Programming
RATHER
EASY DIFFICULTEASY
Released Date1998
1994
dimension of spatial, time, and physical quantities, 3Dgraphic technology can be the important tool to progress.
The next task to study is how to visualize these data

ACKNOWLEDGEMENT
The authors are very grateful to Prof. Sudo at NIFS for
his encouragement. We would also like to thank Mr.
Kojima of the CAD group, and the LHD group for theirhelp.
Figure 4: The temperature distributions before/afterthe beam injection
The higher temperatures are drawn by orange.
advantages. Because VRML is an interpreter language, itis easier to develop than to use Java 3D. There are many
tools to edit and viewing VRML source. However, it isdifficult to write practical applications only by using
VRML, and therefore, it is necessary to combine otherlanguages to realize a more complicated application. On
the other hand, because Java 3D is an API of Java
language, it is easier to build an ordinary application
only by using Java, but there are few modeling tools
directly produce Java sources. Because it is a burden tobuild three-dimensional objects only by Java 3D, arealistic way to make an application is to use bothlanguages. The comparison of VRML and Java 3D islisted in table 2. This application uses VrmlLoader class
to load the VRML sources which describe the geometryof the vacuum vessel.
The application visualizes the data composed of only
spatial dimensions in this case, but the three-dimensional
visualisation technology can be applied to mixed
dimensional data, which means the spatial and chronicle,
or other dimensions. Since in the plasma experiment,
there are various kinds of data which have multi-REFERENCES[1] A. Iiyoshi et al., “An Overview of the Large HelicalDevice Project”, 17th IAEA Fusion Energy
Conference, Yokohama, October 1998
[2] Satarou Yamaguchi et al., J. Plasma Fusion Res.,73(1997) pp. 335-342[3] Joji Kariya et al., J. Plasma Fusion Res., 74 (1998)
pp. 67-75[4] Joji Kariya et al., “Java Based Data Monitoring
System for LHD”, PCaPAC ‘99, Tsukuba, January
1999[5] http://www.vrml.org