This non-signed Java Applet (The Java Run-time Environment
[JRE] has to be installed on your computer
for running this applet.) consisting of 17 classes (total size = 66 kB) (or
merged into a single jar file [size = 45 kB] for Java 1.1.x capable browsers)
and 3 gif files (total size = 70 kB) allows you to inspect
on-line the current official status of the PSI Proton Accelerator Facility. The update
rate of the changing data is 1 Hz at the maximum. Because different parts of the
applet are running in separate single instance windows the browser's window may
be minimized once the applet is started. The applet's main window shows the date
and time, the outside temperature, the total used electrical power, the 6
proton beam currents and the operator's messages all transmitted periodically
via multicast UDP/IP by the ACS (Accelerator Control System). A program running on an own
WWW server (PC9687, OS = Linux) collects
these data and writes them into files located in the applet's own "sandbox" from
where they are fetched by the applet's running instances via http (Apache server is
installed on pc9687).
Three push buttons in the applet's main window allow you to view the gathered data in separate windows in a more detailed form:
|History||The last 1, 12 or 72 hours of the 6 different proton beam currents, the outside temperature and the total electrical power may be seen as a histogram. Refreshing is done automatically with a reasonable frequency.|
|Messages||The collected operator's messages over the last few days are displayed. The text window content is limited to ~7 kB and organized as a FIFO. The Refresh button reloads the (updated) text from the server.|
|HE info||Some statistical data which describe the quality of the 590 MeV proton beam over the last 24 hours are shown. The Refresh button reloads the (updated every 120 sec) table from the server.|
This applet has been seen working on the following platforms (OSes) with browsers:
If you are using a browser with at least Java 1.1.x capabilities (like Netscape's Navigator 4.5 and higher, Sun's Hotjava 1.1 or Microsoft's Internet Explorer 4.0x and higher for Windows platforms), then it will automatically choose the newer version of this applet, which is based on the Java 1.1 API (more reliable) and down-loadable as a single Java archive (faster).
In order to improve the platform independence, the push buttons of the top and the history frame are user-drawn (and colored).
Last updated by Urs Rohrer on 14-Feb-2006