Ben Lauwens | Royal Military Academy Belgium (original) (raw)
Papers by Ben Lauwens
2014 17th International Symposium on Electromagnetic Launch Technology, 2014
The information transfer across the battlespace is expanding at an ever increasing pace. Simulati... more The information transfer across the battlespace is expanding at an ever increasing pace. Simulations have to be carried out to ensure the quality of service of the different applications (sensors, command and control systems, voice communications, . . .) all integrated in a dynamic network environment. Two approaches are common: discrete event simulation and fluid approximation. A discrete event simulation generates a huge amount of events for a full-blown battlefield communication network resulting in a very long run-time. The usability of this simulation technique is very limited for a rapid changing combat theater. A faster fluid based approximation lacks the accuracy wanted for a realistic simulation. A hybrid simulator separates the traffic in two classes. The packets of the foreground traffic, for which fine-grained performance details are needed, are simulated by an event driven approach, while the background traffic, for which less detailed information is required, is approx...
ABSTRACT In this paper we address the slow convergence of the alternating projection method for t... more ABSTRACT In this paper we address the slow convergence of the alternating projection method for the construction of packings in Grassmannian manifolds based on the algorithm in [I. S. Dhillon, R. W. Heath Jr., T. Strohmer, and J. A. Tropp, Constructing packings in Grassmannian manifolds via alternating projection. Exper. Math., vol. 17, num. 1, pp. 9{35, 2008.]. The idea is based on the Broyden quasi-Newton method and shows encouraging results. http://www.bettyjonespub.com/3JMS.pdf
Journal of Computational and Applied Mathematics, 2015
2009 Third International Conference on Sensor Technologies and Applications, 2009
Journal of Electronic Imaging, 2013
ABSTRACT The quality control of composite multilayered materials and structures using nondestruct... more ABSTRACT The quality control of composite multilayered materials and structures using nondestructive tests is of high interest for numerous applications in the aerospace and aeronautics industry. One of the established nondestructive methods uses microwaves to reveal defects inside a three-dimensional (3-D) object. Recently, there has been a tendency to extrapolate this method to higher frequencies (going to the subterahertz spectrum) which could lead to higher resolutions in the obtained 3-D images. Working at higher frequencies reveals challenges to deal with the increased data rate and to efficiently and effectively process and evaluate the obtained 3-D imagery for defect detection and recognition. To deal with these two challenges, we combine compressive sensing (for data rate reduction) with a dedicated image processing methodology for a fast, accurate, and robust quality evaluation of the object under test. We describe in detail the used methodology and evaluate the obtained results using subterahertz data acquired of two calibration samples with a frequency modulated continuous wave system. The applicability of compressive sensing within this context is discussed as well as the quality of the image processing methodology dealing with the reconstructed images.
Journal of Computational and Applied Mathematics, 2014
4OR, 2011
This is a summary of the author’s PhD thesis supervised by Bart Scheers and Antoine Van de Capell... more This is a summary of the author’s PhD thesis supervised by Bart Scheers and Antoine Van de Capelle and defended on 20 November 2009 at the Royal Military Academy, Brussels. The thesis (https://lirias.kuleuven.be/handle/123456789/246952) is written in English and is available from the author upon request. This work deals with an extension to the hybrid simulation paradigm, i.e. the combination of event-driven
Proceedings of the First International ICST Conference on Simulation Tools and Techniques for Communications Networks and Systems, 2008
... Networks Handling Many Traffic Flows Ben Lauwens Royal Military Academy CISS/TELE 30, Renaiss... more ... Networks Handling Many Traffic Flows Ben Lauwens Royal Military Academy CISS/TELE 30, Renaissancelaan Brussels, B-1000, BELGIUM Ben.Lauwens@rma.ac.be ... The tail distribution of ΛN(i) t = PN(i) j=1 Λ(i) t determines the buffer asymptotics by Loynes's theorem [14]. ...
2007 IEEE International Conference on Communications, 2007
Proceedings of the 2nd International ICST Conference on Performance Evaluation Methodologies and Tools, 2007
This paper introduces a novel hybrid packet-event / fluid-flow network simulation scheme. A packe... more This paper introduces a novel hybrid packet-event / fluid-flow network simulation scheme. A packet-event simulation technique uses the arrivals and the departures of packets to model the queuing system. The applications that need fine-grained performance details, are simulated with an adapted event based approach. The impact of the background traffic on these foreground packets is simulated by virtual packets, which
2008 IEEE Sarnoff Symposium, 2008
Proceedings of the 2nd International ICST Conference on Performance Evaluation Methodologies and Tools, 2007
This paper introduces a novel hybrid packet-event / fluid-flow network simulation scheme. A packe... more This paper introduces a novel hybrid packet-event / fluid-flow network simulation scheme. A packet-event simulation technique uses the arrivals and the departures of packets to model the queuing system. The applications that need fine-grained performance details, are simulated with an adapted event based approach. The impact of the background traffic on these foreground packets is simulated by virtual packets, which
Proceedings of the First International ICST Conference on Simulation Tools and Techniques for Communications Networks and Systems, 2008
... Networks Handling Many Traffic Flows Ben Lauwens Royal Military Academy CISS/TELE 30, Renaiss... more ... Networks Handling Many Traffic Flows Ben Lauwens Royal Military Academy CISS/TELE 30, Renaissancelaan Brussels, B-1000, BELGIUM Ben.Lauwens@rma.ac.be ... The tail distribution of ΛN(i) t = PN(i) j=1 Λ(i) t determines the buffer asymptotics by Loynes's theorem [14]. ...
2008 IEEE Sarnoff Symposium, 2008
2007 IEEE International Conference on Communications, 2007
Proceedings of the 3rd International ICST Conference on Simulation Tools and Techniques, 2010
2014 17th International Symposium on Electromagnetic Launch Technology, 2014
The information transfer across the battlespace is expanding at an ever increasing pace. Simulati... more The information transfer across the battlespace is expanding at an ever increasing pace. Simulations have to be carried out to ensure the quality of service of the different applications (sensors, command and control systems, voice communications, . . .) all integrated in a dynamic network environment. Two approaches are common: discrete event simulation and fluid approximation. A discrete event simulation generates a huge amount of events for a full-blown battlefield communication network resulting in a very long run-time. The usability of this simulation technique is very limited for a rapid changing combat theater. A faster fluid based approximation lacks the accuracy wanted for a realistic simulation. A hybrid simulator separates the traffic in two classes. The packets of the foreground traffic, for which fine-grained performance details are needed, are simulated by an event driven approach, while the background traffic, for which less detailed information is required, is approx...
ABSTRACT In this paper we address the slow convergence of the alternating projection method for t... more ABSTRACT In this paper we address the slow convergence of the alternating projection method for the construction of packings in Grassmannian manifolds based on the algorithm in [I. S. Dhillon, R. W. Heath Jr., T. Strohmer, and J. A. Tropp, Constructing packings in Grassmannian manifolds via alternating projection. Exper. Math., vol. 17, num. 1, pp. 9{35, 2008.]. The idea is based on the Broyden quasi-Newton method and shows encouraging results. http://www.bettyjonespub.com/3JMS.pdf
Journal of Computational and Applied Mathematics, 2015
2009 Third International Conference on Sensor Technologies and Applications, 2009
Journal of Electronic Imaging, 2013
ABSTRACT The quality control of composite multilayered materials and structures using nondestruct... more ABSTRACT The quality control of composite multilayered materials and structures using nondestructive tests is of high interest for numerous applications in the aerospace and aeronautics industry. One of the established nondestructive methods uses microwaves to reveal defects inside a three-dimensional (3-D) object. Recently, there has been a tendency to extrapolate this method to higher frequencies (going to the subterahertz spectrum) which could lead to higher resolutions in the obtained 3-D images. Working at higher frequencies reveals challenges to deal with the increased data rate and to efficiently and effectively process and evaluate the obtained 3-D imagery for defect detection and recognition. To deal with these two challenges, we combine compressive sensing (for data rate reduction) with a dedicated image processing methodology for a fast, accurate, and robust quality evaluation of the object under test. We describe in detail the used methodology and evaluate the obtained results using subterahertz data acquired of two calibration samples with a frequency modulated continuous wave system. The applicability of compressive sensing within this context is discussed as well as the quality of the image processing methodology dealing with the reconstructed images.
Journal of Computational and Applied Mathematics, 2014
4OR, 2011
This is a summary of the author’s PhD thesis supervised by Bart Scheers and Antoine Van de Capell... more This is a summary of the author’s PhD thesis supervised by Bart Scheers and Antoine Van de Capelle and defended on 20 November 2009 at the Royal Military Academy, Brussels. The thesis (https://lirias.kuleuven.be/handle/123456789/246952) is written in English and is available from the author upon request. This work deals with an extension to the hybrid simulation paradigm, i.e. the combination of event-driven
Proceedings of the First International ICST Conference on Simulation Tools and Techniques for Communications Networks and Systems, 2008
... Networks Handling Many Traffic Flows Ben Lauwens Royal Military Academy CISS/TELE 30, Renaiss... more ... Networks Handling Many Traffic Flows Ben Lauwens Royal Military Academy CISS/TELE 30, Renaissancelaan Brussels, B-1000, BELGIUM Ben.Lauwens@rma.ac.be ... The tail distribution of ΛN(i) t = PN(i) j=1 Λ(i) t determines the buffer asymptotics by Loynes's theorem [14]. ...
2007 IEEE International Conference on Communications, 2007
Proceedings of the 2nd International ICST Conference on Performance Evaluation Methodologies and Tools, 2007
This paper introduces a novel hybrid packet-event / fluid-flow network simulation scheme. A packe... more This paper introduces a novel hybrid packet-event / fluid-flow network simulation scheme. A packet-event simulation technique uses the arrivals and the departures of packets to model the queuing system. The applications that need fine-grained performance details, are simulated with an adapted event based approach. The impact of the background traffic on these foreground packets is simulated by virtual packets, which
2008 IEEE Sarnoff Symposium, 2008
Proceedings of the 2nd International ICST Conference on Performance Evaluation Methodologies and Tools, 2007
This paper introduces a novel hybrid packet-event / fluid-flow network simulation scheme. A packe... more This paper introduces a novel hybrid packet-event / fluid-flow network simulation scheme. A packet-event simulation technique uses the arrivals and the departures of packets to model the queuing system. The applications that need fine-grained performance details, are simulated with an adapted event based approach. The impact of the background traffic on these foreground packets is simulated by virtual packets, which
Proceedings of the First International ICST Conference on Simulation Tools and Techniques for Communications Networks and Systems, 2008
... Networks Handling Many Traffic Flows Ben Lauwens Royal Military Academy CISS/TELE 30, Renaiss... more ... Networks Handling Many Traffic Flows Ben Lauwens Royal Military Academy CISS/TELE 30, Renaissancelaan Brussels, B-1000, BELGIUM Ben.Lauwens@rma.ac.be ... The tail distribution of ΛN(i) t = PN(i) j=1 Λ(i) t determines the buffer asymptotics by Loynes's theorem [14]. ...
2008 IEEE Sarnoff Symposium, 2008
2007 IEEE International Conference on Communications, 2007
Proceedings of the 3rd International ICST Conference on Simulation Tools and Techniques, 2010