Picture of Nick Filer in 1984  

Dr Nick Filer

Advanced Processor Technologies (APT) Group

Mobile Systems Architecture (MSA) Sub Group

School of Computer Science

Who am I?, Contact Me, Research, Teaching,  Administration, Papers.

Who am I?

I'm a generalist rather than a one topic expert. My Bachelors was in Computer Science at the University of London in Queen Mary College. Aside from lots of computer science I took modules from a few other departments but mainly electrical engineering. It was the late 1970's and there was lots of interest in designing chips and electronic systems to support them.

I moved to the University of Manchester in 1981 doing research initially in signal routing for chips and printed circuit boards and then looking at how techniques from Artificial Intelligence could help electronic systems designers. We produced several so called "expert systems" which could solve design problems and attempt to explain decisions to the designer on request. This lead to attempts to improve the quality of the generated explanations which needed deeper knowledge (semantics) so that the underlying reasons could be elucidated.

Deeper domain knowledge required the information used by design systems to be available not just the data. Information has semantics whereas in general data only has syntax. ...............................................................

In about 2002 a chance discussion caused a change of direction into the simulation of and study of wireless networks for pervasive mobile computing. This interest continues today. 

Contact Me

My address is:

Dr Nick Filer
Room IT415
School of Computer Science
University of Manchester
Oxford Road
Manchester M13 9PL
UK

Tel: +44 (0)161 275 6171
Fax: +44 (0)161 275 6204
Email: nfiler@cs.man.ac.uk

Research

Currently my research has two main themes as briefly introduced here:

  1. Using wireless devices to try and build floorplans (maps) of indoor structures such as rooms and corridors. This has applications in various scenarios but one obvious one is fire fighters entering a burning building which is full of smoke. In practice, the fire fighters are very unlikely to have a floorplan when they arrive, most building do not have good GPS penetration or pre-deployed references that can be use to pin point locations. The fir fighter has a radio though so as to communicate with colleagues. It is well known that radio waves behave in much the same way as light, they reflect, diffract and scatter. This means that when a pulse of RF energy is emitted by a transmitter, very soon after, reflections from nearby surfaces arrive at receivers. With accurate timers (which exist) it is possible to detect these reflections. We have been using pulsed Ultra Wide Band (UWB) radios and using timing information from single and double reflections arriving at receivers we have found that reconstruction of the topology of a room or space is possible.

    Impule response from a 4 wall room.

    Impule response from a 4 Wall Room

    Of course there are problems. To build maps e.g. using triangulation, references are needed. Therefore, out technique also needs references. This one is fairly easy to solve, but not in the standard manner of deploying devices or people to act as the references. Instead, we achieve perfect synchronization by using the refection of the transmitter in each nearby wall as a reference. To a receiver it appears as though the transmitter and each of its reflections emitted a pulse at the same time thus giving us easy to use references. Another problem is ambiguities such as mirror reflections. These can be removed in general by moving the transmitter and tracing its path. If the transmitter moves to the left in the real world but to the right in a reconstruction we know that that reconstruction is a mirror image of reality.

    The original room Model of room
    4 Wall Room with UWB Radio Effect of wall angles on reflections (Exaggerated)

    So far, techniques for 2D and 2.5D (rooms with floor and ceiling) have been developed using ray trace data instead of real radios. The next steps are to use real radios, see if 3D spaces can be reconstructed and to look at practical technology for implementation of such a device.

  2. Most existing wireless simulators work with a predetermined network layout (scenario) and by simulation attempt to determine the behaviour of the network under different traffic loads. Modern simulators allow wireless nodes to move but few allow the nodes to be created (switched on) and destroyed (switched off) at will. We invented the concept of "packet simulation" to allow a simulator to determine the behaviour of a given data link layer medium access control (MAC) protocol for the statistical expectation of all possible network topologies.  Our simulator generates traffic as individual packets of data for transmission between dynamically created and destroyed wireless nodes. We send just one packet of data between each pair of nodes. Thus the topology of our network in continuously changing. This allows the average throughput for all topologies to be measured. This average throughput would be much more difficult to find using more traditional simulation technologies.

This idea is now being extended to higher layers and we are actively developing Network Layer simulations to experiment with routing in highly mobile wireless networks and also looking at Transport Layer protocols especially adaptive protocols that treat different media in different ways so as to maximize network throughput and to try and meet Quality of Service (QoS) targets.

  

Current Projects

Analytical Throughput Calculation for Data link Protocols

Most analytical solutions for the analysis of  wireless networks ignore many of the awkward physical things that happen to signals in the physical layer of a wireless network system. We have been developing statistical models of networks that attempt to model the physical layer more realistically. These models need extension, solution and testing. We are currently working towards development of solutions to equations that describe the behaviour of the Physical and Medium Access Layers of protocols similar to Aloha and IEEE 802.11 (WiFi). Once solved we then need to evaluate how similar the results are to real world situations. This is best done by simulation as the real world  is normally too complex and expensive to build real life experiments in.

If the idea can be got to work then it should be possible to compare the efficiency of different protocols before implementing them. By finding their mean behaviour rather than just the behaviour in a testable subset of scenarios the results obtained should be better than those available to today's designers.

This work is ongoing and we are happy to accept new research student applications in this area.

Throughput Simulation for Data link layer Medium Access Control (MAC) Protocols

We have been studying the throughput that Data link Layer, Medium Access Control protocols such has Aloha and IEEE 802.11  can deliver for ad hoc networks for some time. Using a statistical simulation of a continuously changing ad hoc network topology we can find the mean statistical expectation of the throughput for all topologies. We have applied this technique to pure Aloha, Aloha with CSMA, Aloha with RTS/CTS, IEEE 802.11 using CSMA/CA and using RTS/CTS.

This work is ongoing and we are happy to accept new research student applications in this area.

Throughput Simulation for Network Layer Routing Protocols

The techniques used for simulation at the data link layer should extend to higher layers but the simulation costs will be significantly higher (time and memory needed). It is clear that effort is needed to build more efficient (parallel) simulations so we can accurately simulate ad hoc networks above the data link layer.  We want to assess which are the best protocols and protocol controls (metrics) for ad hoc and mesh networks of mobile wireless users. These systems will need to compete with cellular technologies such as IEEE 802.16 (WiMAX) and IEEE 802.20 in the near future. LAN systems should have an advantage over MAN systems because they have smaller coverage range and serve less users.  However, if  LAN latencies are high then MAN systems will prove more effective for some user densities?

If  you are interested in wireless routing protocols and their applications then please contact us or apply for a research studentship.

Voice over IP and over Wireless/Wired Local Area Networks (VoWLAN).

Modern networks built for both data and telecommunication are increasingly being configured for mainly IP traffic rather than the older switched telephony networks. The internet has been built around best effort quality of service which is sometimes usable but unreliable for multi media data such as voice and video. For example, most data transfers use the TCP/IP protocol which given reliable data transfer but with no promises about when the data will be delivered. In fact TCP/IP may hold back latter packets of data if an earlier packet was lost for some reason.

The design of protocols and their configuration for networks carrying  multi media and other types of traffic is an open topic. New protocols need to be tested in many different scenarios to ensure they behave as designed and to measure how much  better or worse the network's performance is. Protocols exist at all the levels in the network architecture from the application layer through to the physical layer. For many multi media formats, the way in which they are packaged as packets and transmitted can have a very large effect on the efficiency and behaviour of the network. All these and other aspects are good research topics. 

If  you are interested in VOIP or in protocols for multi-media wireless or wired networks then please contact us or apply for a research studentship.

Indoor Environment Mapping using Ultra Wide Band (UWB) Radio

We have been looking at reconstruction of indoor (multi path) environments using the impulse response from UWB radios. Initial research has shown that just using the time of arrival if impulses reflected from walls in different locations around a radio, in general the environment can be constructed and a map drawn. So far we have looked at simple environments and we know that the more complex the environment the more information the radio get back and there is even considerable redundancy.

Further research is required to find the limits of the technology we have developed so far and then to look at what extra information might be used to get around any limits that are found. So for example we need to look at recovery of 3 dimensional location information. We also need to look at recovering information about small objects (smaller than a wall) such as furniture, we expect this information is hidden amongst the noise signals but it might be recovered by signal processing and pattern matching?

Of course we are also interested in using UWB for communications. We are interested in analytical and simulation of the throughput of UWB systems in the presence of external noise (other users of UWB and narrow band systems). Applications of the mapping technology might be, for example firemen entering a smoke filled building where radios used for communication might also one day provide other services such as maps of the local environment.

If  you are interested in Ultra Wide Band and its applications then please contact us or apply for a research studentship.

Teaching

COMP30091 - Digital Wireless Communications and Networks


This final year undergraduate course started in 2006/7 with the aim of introducing computer scientists to the communications tools that we are all now using in our laptops, personal computers and telephones. The course is based around the book "Mobile Communications" by Jochen Schiller. Students take a series of modules based on an introductory lecture, a chapter in the book, some subsidiary reading, self tests and finally a formal short test. The course is evolving towards problem directed learning in a mainly self taught environment using materials provided using a web based teaching support environment. The main modules are:

Wireless Transmission/Physical Layer
Medium Access Control
Telecommunications Systems
Wireless Local  Area Networks (WLAN)
Mobile Network/Transport Layer

Testing for this course is all carried out electronically. The tests that count are taken using the ABC software. The short in course tests use a mixture of multiple choice, one/two word answer and calculation questions. The final examination is traditional in style. The ABC tool makes marking much easier, everything is readable plus answers can be sorted and grouped in many different ways

CS6242 - Mobile Computing

This master's level course is taught jointly with Dr Barry Cheetham. The course is split roughly 50:50 between physical layer and the higher layers. Barry teaches the physical layer and I deal with the higher layers. The aim is to show computer scientists how modern digital communications systems are built. There is a lot of signal processing needed to encode/decode data plus deal with the noise and interference introduced by propagation through a wireless medium. At the higher layers the course shown how the medium can be shared in various ways and how sharing is controlled. Issues of integration of wireless and wired networks are examined to show the differences between the two mediums and how they change the protocols used to manage the network.

Administration

Having spent several years up until 2005/6 managing the undergraduate Software Engineering degree I am a member of the Undergraduate Committee which manages all the school's undergraduate teaching.

I am one of a group of staff members responsible for managing and assessing final year undergraduate projects. Each year I assess between 20-30 projects jointly with project supervisors. This involves attending seminars, looking at posters, attending project demonstrations and finally reading plus examining the project reports.

At postgraduate level I am a member of the postgraduate management committee. My tasks include admissions and monitoring plagiarism.

Papers + Publications

2007

W. Guo &  N. P. Filer, “On the Accuracy of an Indoor Location-sensing Technique Suitable for Impulse Radio Networks", IEEE International Conference on Communications (ICC 2007), Page(s):3987 - 3992,   Glasgow, UK, 24-28 June 2007

2006


W. Guo, N. P. Filer & Rudolf Zetik, “2D Indoor Mapping using Impulse Radios”, Accepted for NEWCOM-ACoRN Joint Workshop, 20 - 22 September 2006.

W. Guo, N. P. Filer & Rudolf Zetik, "Indoor Mapping and Positioning Using Impulse Radios”, pages 153-163, PLANS 2006, San Diego CA, 25-27th April 2006

W. Guo & N. P. Filer, "2.5D Indoor Mapping and Location-Sensing Using an Impulse Radio Network”, pages 211-215, The IET Seminar on Ultra Wideband Systems, Technologies and Applications, IET (IEE) Savoy Place, London, 20th April 2006, ISBN 0-86341-625-X/9780863416255, ISSN 0537-9989 Ref 06/11371

2005

Ritun Patney, Nick Filer, and Stephen K. Barton, "Server Supported Routing: A Novel Architecture and Protocol to Support Inter-Vehicular Communication”, In Proceedings, Mobile Ad-hoc and Sensor Networks: First International Conference, MSN 2005, Ed: Xiaohua Jia, Jie Wu, Yanxiang He Wuhan, pp.21 - 30, China, December 13-15, 2005. Lecture Notes in Computer Science, Volume 3794/2005, Springer-Verlag GmbH, ISSN 0302-9743 , ISBN:3-540-30856-3

W. Guo, S. Thomson, N. P. Filer and S. K. Barton, “Knowledge Base Assisted Mapping for an Impulse Radio Indoor Location-sensing Technique”, Proc. International Workshop on Wireless Ad-hoc Networks (IWWAN), May-2005.

W. Guo, N. P. Filer and S. K. Barton, “Knowledge Representation for an Impulse Radio Indoor Location-sensing Technique”, In: Proc. Postgraduate Research Conference in Electronics, Photonics, Communications and Networks, and Computing Science (PREP), March 2005

W. Guo, N. P. Filer and S. K. Barton, “Mapping Closed Four-wall Environments Using a Single Impulse Radio”, Cost 273 Meeting Bologna Italy, January 2005, Ref: TD (05) 10, <http://www.lx.it.pt/cost273/>

A. Tamburini, N. P. Filer  and S. K. Barton, “Multi Protocols Interference Evaluation Module”, Cost 273 Meeting Bologna Italy, January 2005, Ref: TD (05) 042, <http://www.lx.it.pt/cost273/>

2004

N. P. Filer and S. K. Barton, “Towards a Performance Comparison of WLAN MAC Protocols”, pp. xx-yy, Proc. the 1st International Symposium on Broadband Communications (ISBC'04), Leeds, December 2004, ISBN: 0853162417

W. Guo, N. P. Filer and S. K. Barton, “A 2D UWB Indoor Wireless Technique for Location-Aware Applications”, pp 58, Proc. the 1st International Symposium on Broadband Communications (ISBC'04), Leeds, December 2004, ISBN: 0853162417

A. Pickering, N. Filer and S. K. Barton, “Simulation Tool for Estimating RF Energy from Cellular Telephony”, In: Proc. the 1st International Symposium on Broadband Communications (ISBC'04), December 2004, ISBN: 0853162417

Wenyu Guo, Nick Filer and Stephen K Barton, “A Novel Wireless Mapping and Positioning Technique for Impulse Radio Networks”, pages 712-714, 2004 International Symposium on Electromagnetic Theory, Union Radio-Scientifique Internationale (URSI), Pisa, Italy, May 23-27, 2004.
Also published as Cost 273 Meeting Duisburg,  September 2004, Ref: TD (04) 147, <http://www.lx.it.pt/cost273/>.

N. P. Filer and S. K. Barton, “Wireless Network Throughput Simulation Modelling the Physical Layer with Hidden Nodes” Cost 273 Meeting Duisburg, September 2004, Ref. TD (04) 170, <http://www.lx.it.pt/cost273/>

W. Guo, N. P. Filer and S. K. Barton, “2D Indoor Mapping and Positioning Using an Impulse Radio Network”, pages 119-122, The IEE Seminar on Ultra Wideband Communications Technologies and System Design, Queen Mary, University of London, 8th July 2004, ISBN 0-86341-442-7, ISSN 0537-9989.

W. Guo, N. P. Filer and S. K. Barton, "A Feasibility Study on 2D Indoor Environment Mapping Using a Single Impulse Radio”, In Proc. 5th Annual Postgraduate Symposium on the Convergence of Telecommunications, Networking and Broadcasting (PGNet), June 2004, pp 241-246.

W. Guo, N. P. Filer and S. K. Barton, “Resolving mirror-image ambiguity in scenarios reconstructed by impulse radio networks”, In: Proc. Postgraduate Research Conference in Electronics, Photonics, Communications and Networks, and Computing Science (PREP), April 2004, pp: 264-265

2003

X. Y. Li, Np. F. Filer and S. K. Barton, “Using Packet Based Simulation to Directly Measure the Throughput of a Wireless Ad-Hoc Network Under the Aloha Protocol”, Cost 273 Meeting Prague, 24th September 2003, Ref: TD (03) 184, <http://www.lx.it.pt/cost273/>

2001

Nick P. Filer, Hilary J Kahn, Alan Williams and Nigel Whitaker, “A generic framework for transforming EXPRESS information models”, Computer Aided Design Journal, Vol. 33, pages 501-510, Elsevier, ISSN: 0010-4485, 2001.

NP Filer, HJ Kahn, AR Williams, NA Whitaker, D Reilly, "From information model to controllable implementation", pages 307-328, In: "Information Modeling in the New Millennium", Edited by: M. Rossi and K. Siau, Idea Group Publishing, ISBN 1-878289-77-2, 2001.

2000

Hilary J Kahn, A. J. Williams and N. P. Filer, “Geotechnical Site Investigation: A Model Based Study”, Proceedings of the Third European Conference on Product and Process Modeling in the Building and Related Industries, Lisbon, Portugal, September 2000. In "Product and Process Modeling in Building and Construction", Edited by Ricardo Goncalves, Adolfo Steiger-Garcao & Raimar Scherer, A. A. Balkema Publishers, ISBN 90-5809-179-1.

Nick P. Filer and Hilary J. Kahn, “Supporting the Maintenance and Evolution of Information Models”, pages 888-890, Information Resources Management Association International Conference (IRMA) 2000, In "Challenges of Information Technology Management in the 21st Century", Edited by Mehdi Khosrowpour, Pennsylvania State University; ISBN 1-878289-84-5 Anchorage, May 2000.

N. Filer, H. Kahn, A. Williams, N. Whitaker and D. Reilly. “Transforming Information Models to Support the Generation of Efficient Implementations”, Proceedings of the Thirty-Third Annual Hawaii International Conference on System Sciences, Maui, Hawaii, USA, January 4th-7th, 2000, ISBN 0-7695-0493-0.

1999

Andrew Broad and Nick Filer, “Extracting Constraint Knowledge From Code: A Case-Based Reasoning Approach”, Pages 83-96 in: Bramer M., Macintosh A. and Coenen F. (editors). Research and Development in Intelligent Systems XVI: Proceedings of ES99, The Nineteenth SGES International Conference on Knowledge Based Systems and Applied Artificial Intelligence, Cambridge, England, 13th-15th December 1999. Springer-Verlag, London. ISBN 1-85233-231-X.

Andrew Broad and Nick Filer, “Applying Case-Based Reasoning to Code Understanding and Generation”, Pages 35-48 in: Watson I., editor. Proceedings of the Fourth United Kingdom Case-Based Reasoning Workshop (UKCBR4), University of Salford, Salford, England, 15th September 1999.

Nick P. Filer and Hilary J Kahn, “Creating Efficient Implementations from EXPRESS Information Models”, pages 835-840, Information Resources Management Association International Conference (IRMA) 99, In "Managing Information Technology Resources in Organizations in the Next Millennium", Ed. M. Khosrowpour, Hershey USA, Idea Group Publishing, ISBN 1-878289-51-9.

1997

“3rd United Kingdom Case-Based Reasoning Workshop Proceedings”, Editors N. P. Filer and I. Watson, Department Of Computer Science, University of Manchester, Manchester M13 9PL, September 1997.

N. Filer, “CBR for Understanding of Very Large Electronic Legacy Objects”, 14 pages, In: N. Filer & I. Watson (editors), “3rd United Kingdom Case-Based Reasoning Workshop Proceedings”, Department Of Computer Science, University of Manchester, Manchester M13 9PL, September 1997.

1995

M. Brown, N. Filer and I. Watson, “Separating the Cases from the Data: Towards More Flexible Case-Based Reasoning”, pages 157-168, In: Case-Based Reasoning Research and Development, First International Conference, ICCBR-95, edited by: M. Veloso and A. Aamodt, Lecture Notes in Artificial Intelligence 1010, Subseries of Lecture Notes in Computer Science, Sesimbra, Portugal, October, 1995, Springer, ISBN 3-540-60598-3.

M. Brown, Z. Moosa, N. Filer, J. Heaton and J. Pye, “Practical Inter-Operation of CAD Tools Using a Flexible Procedural Interface”, pages 34-39, “EURO-DAC '95” European Design Automation Conference With EURO-VHDL, Brighton, UK, September, 1995, IEEE Computer Society Press, ISBN 0-7803-3080-3.

Z. Moosa, M. Brown, N. Filer, J. Heaton and J. Pye, “Close Integration of a CAD Vendor's Framework into the Jessi-Common-Frame Using a Flexible and Adaptable Procedural Interface”, pages 457-466, International Workshop on Concurrent/Simultaneous Engineering Frameworks and Applications, Lisbon, Portugal, April, 1995.

M. Brown and N. Filer, “Beauty vs the Beast: The Case Against Massively Parallel Retrieval”, Section 1.4, 13 pages, 1st United Kingdom Case-Based Reasoning Workshop, I Watson and S Perera (Editors), Research and Graduate College, University of Salford, January, 1995.
Also in: “Advances in Case Based Reasoning: First UK CBR Workshop”, pages 42-58, Lecture Notes in Artificial Intelligence, Subseries of Lecture Notes in Computer Science No. 1020, I Watson (editor), 1995, Springer, ISBN 3-540-60654-8.

1994

S. Mir and N. Filer, “Re-engineering Hardware Specifications by Exploiting Design Semantics”, pages 336-341, “EURO-DAC '94” European Design Automation Conference With EURO-VHDL, Grenoble, France, September, 1994, IEEE Computer Society Press, ISBN 0-89791-685-9.

Z. Moosa, M. Brown and N. Filer. “Integrating CAD Tools into a Framework Environment Using a Flexible and Adaptable Procedural Interface”, pages 200-205, “EURO-DAC '94” European Design Automation Conference With EURO-VHDL, Grenoble, France, September, 1994, IEEE Computer Society Press, ISBN 0-89791-685-9.

Z. Moosa, M. Brown and N. Filer. “The Use of Semantic Information for Control of a Complex Routing Tool”, pages 342-347, “EURO-DAC '94” European Design Automation Conference With EURO-VHDL, Grenoble, France, September, 1994, IEEE Computer Society Press, ISBN 0-89791-685-9.

Z. Moosa, M. Brown and N. Filer, “Knowledge Based Support for Use of Complex CAD Tools”, pages 175-188, ES 94, Editors: R. Milne and A. L. Macintosh, In: Applications and Innovations in Expert Systems II - Proceedings of Expert Systems 94 the 14th Annual Conference of the British Computer Society Specialist Group on Expert Systems, Cambridge, UK, December, 1994, SGES Publications, ISBN 1 899621 00 8.

M. Brown and N. Filer, “Case Retrieval Must Use Massive Parallelism?”, pages 119-132, ES 94, Editors: M. A. Bramer and A. L. Macintosh, In: Research and Development in Expert Systems XI the 14th Annual Conference of the British Computer Society Specialist Group on Expert Systems, Cambridge, UK, December, 1994, SGES Publications, ISBN 1 899621 01 6.

S. Mir and N. Filer, ”Heuristic Classification of Cells in Logic Electronic Specifications”, The 10th IEEE Conference on Artificial Intelligence for Applications, San Antonio, Texas, USA, March 1994.

1991

D. Wray, S. Mir and N. Filer, “Description of a Prototype Knowledge-Based Tool Exploiting Design Semantics”, Joint European Submicron Silicon Programme : JESSI-CAD-FRAME (JCF), Review Material “SP1 Applied Framework Research (D1.1), ESPRIT special project 5082, pages A1.56--A1.71, CADLAB, University of Paderborn, Germany, April 1991.

D. Wray, S. Mir, N. Filer and H. J. Kahn, “A Prototype Browser for Design Information and Semantics Captured from a Design Representation in EDIF”, Joint European Submicron Silicon Programme : JESSI-CAD-FRAME (JCF), Workshop Proceedings “SP1 Applied Framework Research (M1.1), ESPRIT special project 5082, pages 50--56, Forschungszentrum Informatik (FZI) University of Karlsruhe, Germany, January 1991.

A. R. Williams, N. P. Filer and H. J. Kahn, “Isomorphic and Non-Isomorphic Hierarchies in CAD Systems”, Joint European Submicron Silicon Programme : JESSI-CAD-FRAME (JCF), Workshop Proceedings “SP1 Applied Framework Research (M1.1), ESPRIT special project 5082, pages 20--26, Forschungszentrum Informatik (FZI) University of Karlsruhe, Germany, January 1991.

Poster presentation: S. Mir, N. P. Filer and H. J. Kahn,  “Using Semantic Information to Reason about the Structure of VLSI Designs”, EDAC, The European Conference on Design Automation, Amsterdam, February, 1991.

1990

“Proceedings of the 5th Workshop on Explanation”, Editor: N. P. Filer, University of Manchester, 183 pages, April 1990.

S. Mir and N. P. Filer, “Using Multiple-levels of Knowledge to Reason About the Structure of VLSI Digital Circuits”, DTI Deep Knowledge Workshop, Wales, April, 1990.

1989

N. P. Filer, “Using Knowledge-Based Systems With CAD”, IEE Computing and Control Division, Colloquium organised by Professional Group C2 (Hardware and systems engineering) on “High Level Modelling and Design for ASICS”, Pages 5/1--5/4, London, October, 1989.

R. A. J. Marshall and N. P. Filer, “The Design of a Methodology for the Intelligent Control of Simulation Using the Manchester Simulation Engine”, In “Simulation Methodologies, Languages and AI and Graphics for Simulation” Proceedings of the 1989 European Simulation Multiconference, Pages 163--168, Rome, June 1989.

N. P. Filer, “Possible Techniques for the Generation of Explanations in a Simulation Environment”, Alvey/SERC Deep Knowledge Workshop, Sunderland Polytechnic, March 1989.

1988

“Proceedings of the 4th Alvey/SERC Workshop on Explanation”, Editor: N. P. Filer, University of Manchester, Published by : Institute of Electrical Engineers, 247 pages, September 1988.

N. P. Filer, “Report on a Discussion of the Semantics of Graphs”, Proceedings of the 4th Alvey/SERC Workshop on Explanation, pages 4--14, University of Manchester, September 1988.

D. C. Y. Ng and N. P. Filer, “Demonstration of the `Manchester Graphical Explanation Environment’ : MAGEE”, Proceedings of the 4th Alvey/SERC Workshop on Explanation, pages 37--49, University of Manchester, September 1988.

N. P. Filer, “The use of Knowledge Based Techniques for Electronic Computer Aided Design”, Ph.D thesis, Department of Computer Science, University of Manchester, June 1988.

1987

M. A. Spink and N. P. Filer, “Knowledge Based Control for VLSI”, IEEE International Workshop on AI-Applications to CAD-Systems for Electronics, pages 119--136, Munich, Germany, October 1987.

N. P. Filer, “CAD Layout Tools Applied to Interactive Structure Diagram Layout”, Proceedings of the 3rd Alvey/SERC Workshop on Explanation, University of Surrey, September 1987.

M. A. Spink and N. P. Filer, “A Knowledge Based Abutment Aid for Layout Generation within a General Silicon Compiler”, Proceedings of the 1987 Electronic Design Automation Conference, pages 109--119, London, July 1987.

1986

N. P. Filer, “Explanation by an Expert System for Computer Aided Computer Design”, Proceedings of the 1st Alvey/SERC Workshop on Explanation, University of Surrey, March 1986.

1985

N. P. Filer and H. J. Kahn, “An Application of Knowledge Based Techniques to VLSI Design”, Expert Systems 1985, Fifth Technical Conference of the British Computer Society Specialist Group on Expert Systems, Edited by: M. Merry, pages 307--322, University of Warwick, Cambridge University Press, December 1985, ISBN 0-521-32596-X.

1982

N. P. Filer, “A Line-Search Method for the Routing Problem in a Practical Environment”, M.Sc. thesis, Department of Computer Science, University of Manchester, October 1982.