Measurement Techniques in 
High Energy Physics at KTH


Announcing the

Virtual Intelligence - Dynamic Neural Networks VI-DYNN'98 Workshop



A workshop on PCNN theory and applications, as well as dynamic neural network models

Tobias, Maxim, Thomas, Clark

Personnel:

Sölve, Åge,Clark,Givi,Guy,Kenneth
Jason
 
Mary Lou and Bruce

ANNSR2: Applications of Neural Networks in Scientific Research

The ANNSR2 Collaboration during a meeting in Stockholm.

Recent Activities and Publications

pcnn sequence
Including our work in Pulse Coupled Neural Networks


Don't miss our

Neural Networks In High Energy Physics


Overview

Measurement techniques and data processing applied to the micro world often involves a whole different approach than that for our ordinary macroscopic world. This is for a number of reasons: one must usually destroy the very object that one wishes to study, one must describe the object of interest from examining the debris of that destruction, the background noise can be 100 million times stronger that the desired signal, the data volumes generated can consume thousands of high density magnetic tapes, etc.

The data processing chain includes detectors (e.g. particle trackers like wire chambers), fast electronics for event filtering (or "triggering") so that only the small number of events of interest are actually written to tape, highband width links to computer clusters for more event filtering before writing to tape. Further data processing then occurs off-line as various "cuts" are applied to the data to enhance the signals. We study techniques that cover each of these links in the chain from the data acqusition to on-line and off-line filtering and, finally, to analysis of large databases. For further discussion, see the following:


Diploma Work

If you are interested in doing your diploma work with us, click here in order to find out what projects are available right now.


Neural Networks

Clark Lindsey and Givi Sekhniaidze holding IBM ZISC neural network PC and VME cards respectively.

The primary emphasis of our group is fast pattern recognition and signal processing, especially with the use of neural networks implemented in hardware. Such hardware systems could for example, be used in the real-time triggering systems of high energy physics detectors. Neural networks allow for robust pattern recognition for data with large statistical fluctuations and noise. Their inherent parallel architecture provides fast performance if implemented in hardware (as opposed to the usual simulations in conventional sequential cpu's.) Our group has built prototype or purchase neural networks using such devices as the Intel ETANN, IBM ZISC036, and the Bellcore CLNN. Applications studied include pion recognition from Cherenkov detectors, and secondary vertex event tagging using silicon vertex detector tracking signals. See our Neural Networks in High Energy Physics page that we have created (along with Prof. Bruce Denby of Univ. of Versailles) for further information. Also, see the hypertext version of our review paper on hardware neural networks (see also the new framed version for Netscape 2.0 users).
Some of the current applications we are studying include:

There have been several neural network and wavelet hardware cards constructed (*) or purchased by the group over the past few years. These include:
   
Intel ETANN VME card* Intel's Multi-chip Board holding  
up to 8 ETANN's 
IBM ZISC VME card*
     
IBM ZISC PC card*  PCMCIA card with 3 ZISC036 chips  
Available from Giat Industries 
Neuroptics ISA card  
with 16 ZISC's 
     
NeuraLogix NLX Chips:  
VME card * (top)  
PC card (bot) 
TOTEM ISA Card  
built by Univ. Trento 
Wavelet card with  
2 Aware Inc. chips * 
 
Adaptive Solutions:  
PCI Card with  
128 processors 

ATM

We are currently also engaged in the NEBULAS project (also called RD-31). This project is studying the use of the Asynchronous Transfer Mode ( ATM), often referred to under the title of broadband digital networks, for use in data acqusition in future experiments at such accelerators as the LHC at the CERN laboratory in Geneva, Switzerland. Collaborators in NEBULAS include groups from CERN, Saclay, Uppsala University, and the Alcatel company. ATM was developed by the telecommunications industry but has now become of great interest for general networking, including LAN's of PC's and workstations. The base rate is 155Mbits/sec (compared to 10Mbits/sec for ethernet). Using fixed length packets of 53 bytes (5 byte header + 48 byte payload), the packets travel "point to point" over dedicated links, rather than via shared media as in ethernet or token rings. Switches read the packet headers to determine the destination address of the packets. ATM treats data, audio and video equally (higher layer protocols distinguish the packets) and so will become a central part of the "multimedia superhighway" of the future. NEBULAS hopes to take advantage of the rapid developments of this technology to overcome many of the limitiations of current data acquisition systems that have serious bottlenecks, e.g. data buses, that will hamper the huge data rates at LHC detectors. See the High Speed Interconnect page at CERN for more information on ATM and other broadband technologies. Also, see the list of ATM links. We have recently tested two Olicom 155Mbit/sec EISA cards and used them to send ATM packets between two PC's.
Part of the NEBULAS-Collaboration during a meeting in Stockholm.

KTH-Frescati Home Page 
Curator:Clark S. Lindsey -lindsey@particle.kth.se)