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   Centre de Recherche en Automatique de Nancy (CRAN UMR 7039 CNRS / UL)
 Christian DAUL, Professeur des Universités   Université de Lorraine / ENSEM
  2 avenue de la forêt de Haye
  
 
  54516 Vandœuvre les Nancy
  03 72 74 39 47
  ENSEM, bureau N° 111 couloir gris

 

Publications

PUBLICATIONS 

31 journal papers, 49 international conference papers, 2 times keynote speaker in international conferences, guest editor in special issues of international journals, reviewer for international journals and conferences, etc.

Journal Papers (the title gives access to the abstract, links to pdf files of open access papers are provided)

  1. Prisca Rakotomanga, Charles Soussen, Grégoire Khairallah, Marine Amouroux, Sergey Zaytsev, Elina Genina, Hang Chen, Alain Delconte, Christian Daul, Valery Tuchin, Walter Blondel, Source separation approach for the analysis of spatially resolved multiply excited autofluorescence spectra during optical clearing of ex vivo skinBiomedical Optics Express, Volume 10, Number 7, pages 3410-3424, 2019

  2. Dinh-Hoan Trinh and Christian Daul,  On illumination-invariant variational optical flow for weakly textured scenesComputer Vision and Image Understanding, Vol.179, Issue C, pages 1-18, 2019.

  3. Christian Daul et Didier Wolf, Analyse d’images endoscopiques. Mosaïquage d’imagesTechniques de l'Ingénieur, MED920, 24 pages, Août 2018. 

  4. Christoph Blankenburg, Alexander Rack, Christian Daul and Joachim Ohser, Torsion estimation of particle paths through porous media observed by in-situ time-resolved microtomography, Journal of Microscopy, vol. 266, Issue 2, pages 141-152, May 2017. 

  5. Achraf Ben-Hamadou, Christian Daul and Charles Soussen, Construction of extended 3D field of views of the internal bladder wall surface: a proof of concept, 3D Research, vol. 7, issue 3, September 2016

  6. Maria N. Kholodtsova, Christian Daul, Victor B. Loschenov and Walter C.P.M. Blondel, Spatially and spectrally resolved particle swarm optimization for precise optical property estimation using diffuse-reflectance spectroscopy, Optics Express, vol. 24, number 12, pages 12682-12700, 2016 (pdf, open access).

  7. Christoph Blankenburg, Christian Daul and Joachim Ohser, Estimating torsion of digital curves using 3D image analysis, Image Analysis and Stereology, vol. 35, n°2, pages 81-91, 2016 (pdf, open access).  

  8. Sharib Ali, Christian Daul, Ernest Galbrun, and Walter Blondel, Illumination invariant optical flow using neighborhood descriptors, Computer Vision and Image Understanding, vol. 145, pages 95-110, April 2016.

  9. Sharib Ali, Christian Daul, Ernest Galbrun, François Guillemin and Walter Blondel, Anisotropic motion estimation on edge preserving Riesz wavelets for robust video mosaicing, Pattern Recognition, vol.51, issue C, pages 425-442, March 2016. 

  10. Nina Kalyagina, Tatiana Savelieva, Walter Blondel, Christian Daul, Didier Wolf,and Victor Loschenov, Two-Stage Analysis on Models for Quantitative Differentiation of Early-Pathological Bladder StatesInternational Journal of Photoenergy, Special Issue on Novel Photomedicine, Article ID 230829, 7 pages, 2014 (pdf, open access)

  11. Achraf Ben-Hamadou, Charles Soussen, Christian Daul, Walter C.P.M. Blondel, Didier Wolf. Flexible calibration of structured-light systems projecting point patternsComputer Vision and Image Understanding, vol. 117, issue 10, pages 1468-1481, 2013.

  12. Hector Perez-Ponce, Christian Daul, Didier Wolf, Alain Noel. Validation of a digital mammographic unit model for an objective and highly automated clinical image quality assessmentMedical Engineering and Physics, vol. 35, issue 8, pages 1089-1096, 2013.

  13. Thomas Weibel, Christian Daul  Didier Wolf, Ronald Rösch, François Guillemin. Graph based construction of textured large field of view mosaics for bladder cancer diagnosisPattern Recognition, vol.  45, issue 12, pages 4138-4150, 2012.

  14. Alain Tiedeu,  Christian Daul, Aude Kentsop, Pierre Graebling, Didier Wolf, Texture-based analysis of clustered microcalcifications detected on mammogramsDigital Signal Processing vol. 22, issue 1, pages 124-132, 2012.

  15. Hector Perez-Ponce, Christian Daul, Didier Wolf, Alain Noel. Computation of realistic virtual phantom images for an objective lesion detectability assessment in digital mammographyMedical Engineering and Physics, vol. 33, issue 10, pages 1276-1286, 2011.

  16. Nina Kalyagina, Victor Loschenov, Christian Daul, Didier Wolf, Walter Blondel , Tatiana Savelieva. Experimental and Monte Carlo investigation of visible diffuse reflectance imaging sensitivity to diffusing particle size changes in an optical model of a bladder wallApplied Physics B: Lasers and Optics, vol. 105, issue 3 pages 631-639, 2011.

  17. Yahir Hernandez-Mier, Walter Blondel, Christian Daul  Didier Wolf,  François Guillemin, Fast construction of panoramic images for cystoscopic exploration, Computerized Medical Imaging and Graphics, vol. 34, issue 7, pages  579-592, 2010.

  18. Christian Daul, Juan Lopez-Hernandez, Didier Wolf, Gilles Karcher, Gérard Ethevenot, 3-D multimodal cardiac data superimposition using 2-D image registration and 3-D reconstruction from multiple views, Image and Vision Computing, vol.  27, issue 6, pages 790-802, 2009.

  19. Rosebet Miranda, Christian Daul, Walter Blondel, Yahir Hernandez-Mier, Didier Wolf, François Guillemin. Mosaicing of bladder endoscopic image sequences: distortion calibration and registration algorithm, IEEE Transactions on Biomedical Engineering, vol. 55, issue 2, pages 541-553, 2008.

  20. Alain Noel, Christian Daul, Pierre Aletti, Didier Wolf, Claude Iung, De nouvelles modalités de traitement avec de nouvelles modalités d'imagerie, Radioprotection,  vol. 41, issue 5, pages 177-196, 2007 (pdf, free access).

  21. Ruben Posada, Christian Daul, Didier Wolf, Pierre Aletti. Towards a non Invasive Intracranial Tumor Irradiation using 3-D Optical Imaging and Multimodal data Registration, International Journal of Biomedical Imaging, 14 pages,  ID 62030, 2007 (pdf, open access).

  22. Walter Blondel, Christian Daul, Sandrine Villette, Rosebet Miranda, Yahir Hernandez-Mier, Geneviève Bourg-Heckly, Didier Wolf. Spectro-imagerie endoscopique d'autofluorescence et cartographie 2D pour la localisation et le diagnostic in situ de lésions cancéreuses, Traitement du Signal, vol.  23 pages 213-233, 2006 (pdf, free access).

  23. Christian Daul, Pierre Graebling, Alain Tiedeu, Didier Wolf.. 3-D reconstruction of microcalcification clusters using stereo-imaging: algorithm and mammographic unit calibration, IEEE Transactions on Biomedical Engineering, vol.  52, issue 12, pages 2058-2073, 2005.
  24. Alain Tiedeu, Christian Daul, Pierre Graebling, Didier Wolf. Correspondences between microcalcification projections on two mammographic views acquired with digital systems. Computerized Medical Imaging and Graphics, vol. 29, issue 7, pages 543-553, October 2005.

  25. Alain Tiedeu, Bruno Boyer, Joseph. Stinès, Christian Daul, Pierre Graebling, Dideir Wolf et S. Domngang. Mise en correspondance de microcalcifications mammaires radiographiées sous différents angles, Journal de radiologie, Vol. 86, issue 12-C1, pages 1789-1794, décembre 2005.

  26. Christian Daul, Pierre  Graebling, Alain Tiedeu, Serge. Neossi, Joseph Stinès et Didier Wolf. Reconstruction 3D des foyers de microcalcifications : calibration du système et algorithme. Le sein,  vol. 12, issue 1-2, pages 31-40, 2002.

  27. Gaëlle Valet, Stéphane Sanchez, Gilles. Karcher,  Chritian  Daul et Didier Wolf. Segmentation et recalage en imagerie cardiaque multimodalités, Récents Progrès en Génie des Procédés, Visualisation, Image Modélisation, vol. 15, issue 78, pages 181-187, 2001.

  28. Didier Wolf, Régid Gresson, Joseph Stinès, Christian Daul et P. Troufléau. Reconstruction 3D des foyers de microcalcifications, Journal de radiologie, Vol. 82, issue 6, pages 647-651, Juin 2001.

  29. Christian Daul, Ronald Rösch and Bernhard Claus, Building a color classification system for textured and hue homogeneous surfaces: system calibration and algorithm, Machine Vision and Applications, vol. 12, issue. 3, pages 137-148, October 2000.

  30. Christian Daul, Pierre Graebling and Ernest Hirsch, From the Hough transform to a new approach for the detection and approximation of elliptical arcs, Computer  Vision and  Image Understanding , vol. 72, issue. 3, pages  215-236, December 1998.

  31. Ernest Hirsch, Christian Daul, Cyril Boucher et Pierre. Graebling. Implémentation et application de systèmes de vision construits  autours de structures hétérogènes distribuées à processeurs parallèles, Les calculateurs parallèles, vol. 6, issue 3, pages 67-72, 1994

International conferences

  1. Tan-Binh Phan, Dinh-Hoan Trinh, Dominique Lamarque, Didier Wolf, Christian Daul, Dense Optical Flow for the Reconstruction of Weakly Textured and Structured Surfaces: Application to Endoscopy, IEEE International Conference on Image Processing (ICIP), Tapei, Taiwan, October 2019

  2. Dinh-Hoan Trinh, Christian Daul, Walter Blondel and Dominique Lamarque, Mosaicing  of  images  with few  textures  and  strong illumination changes:  Application  to  gastroscopic scenes, IEEE International Conference on Image Processing (ICIP), pp. 1263 – 1267, Athens, Greece, October 2018

  3. W Blondel, P Rakotomanga, G Khairallah, C Soussen, W Feng, D Zhu, H Chen, C Daul, A Delconte, F Marchal, M Amouroux, Skin optical properties modifications using optical clearing agents: experimental and modelling results, International Conference Laser Optics (ICLO), St. Petersburg, Russia,  June 2018.

  4. Maxim Loshchenov, Walter Blondel, Marine Amouroux, Rudolf Steiner, Aleksandr Potapov, Denis Golbin, Oleg Loran, Akobirkhon Babaev, Aleksandr Borodkin, Christian Daul, Dinh-Hoan Trinh, Victor Loschenov, Multimodal fluorescence imaging navigation for surgical guidance of malignant tumors in photosensitized tissues of neural system and other organs, Unconventional Optical Imaging,  Proc. SPIE, vol.10677, May 2018.

  5. Marine Amouroux, Sébastien Le Cunff, Khuram Faraz, Christian Daul and Walter Blondel, “Consumer vs. an innovative devices' ability to generate images for teledermatology.” in 2nd International Symposium on Physics, Engineering and Technologies for Bio-Medicine (PETBM), Moscow, Russia, October 10-15, 2017.

  6. Walter Blondel, Rakotomanga Prisca, Charles Soussen, Christian Daul, Grégoire Khairallah, Frédéric Marchal, Marine Amouroux, Alain Delconte, Maria Kholodtsova, Viktor Loschenov, Overview on inverse problem solving techniques to estimate optical properties from fibered spectroscopic devices, in 2nd International school for young scientists “Physics, Engineering and Technologies for Biomedicine, Moscow, Russia. October 8-9, 2017.

  7. Marine Amouroux, Sébastien Le Cunff, Khuram Faraz, Christian Daul and Walter Blondel, Definition of image quality criteria for telemedicine-based consultation, in 2nd International school for young scientists “Physics, Engineering and Technologies for Biomedicine, Moscow, Russia. October 8-9, 2017.

  8. Dinh-Hoan Trinh, Walter Blondel and Christian Daul, A General Form of Illumination-Invariant Descriptors in Variational Optical Flow Estimation, IEEE International Conference on Image Processing (ICIP), pages 2533-2537, Beijing, China, September 17-20, 2017.

  9. Khuram Faraz, Walter Blondel, and Christian Daul, Global Adjustment for Creating Extended Panoramic Images in Video-dermoscopy, European Conference on Biomedical Optics (ECBO), in Clinical and Preclinical Optical Diagnostics, J. Brown, ed., Vol. 10411 of SPIE Proceedings, Munich, Germany, 25–29 June 2017.

  10. Walter Blondel, Prisca Rakotomanga, Maria Kholodtsova, Christian Daul, Viktor Loschenov et al.  On the estimation of tissue optical parameters from diffuse reflectance spectroscopy. The International Conference on Coherent and Nonlinear Optics and Lasers, Applications, and Technologies conference (ICONO-LAT), Minsk, Belarus. December 2016.

  11. Khuram Faraz, Walter Blondel, Marine Amouroux, Christian Daul. Towards skin image mosaicing. 6th International Conference on Image Processing Theory, Tools and Applications (IPTA), Oulu, Finland, December 2016.

  12. Christoph Blankenburg, Christian Daul and Joachim Ohser, Parameter free torsion estimation of curves in 3D images, IEEE Int. Conf. on Image Processing (ICIP), pages 1081-1085, Phoenix, Arizona, USA, September 25-28, 2016

  13. Maria Kholodtsova, Walter Blondel, Christian Daul and Viktor Loschenov, Particle swarm optimisation combined to spectral fitting approach improves precision for parametric estimation of tissue optical properties. In SPIE Biophotonics Japan International Conference, Tokyo, Japan, October 27-28, 2015

  14. Sharib Ali, Khuram Faraz, Christian Daul and Walter Blondel, Optical flow with structure information for epithelial image mosaicing, 37th Annual International Conference of the IEEE Engineering in Medecine and Biology Society (EMBC),  pages 1981-1984, Milan, Italy, August 25-29, 2015

  15. Christoph Blankenburg, Christian Daul and Joachim Ohser, Torsion of particle trajectories trough pore space and its estimation using information on local pixel configurations, 14th International Congress for Stereology and Image Analysis, in Acta Stereologica, Liège, Belgium, July 7-10, 2015.

  16. Sharib Ali, Christian Daul, Ernest Galbrun, Marine Amouroux, François Guillemin and Walter Blondel, Robust bladder image registration by redefining data-term in total variational approach, SPIE Medical Imaging: Image Processing conference, Orlando, USA, 21-26 February 2015.

  17. Sharib Ali, Christian Daul and  Walter Blondel, Robust and accurate optical flow estimation for weak texture and varying illumination conditions: Application to cystoscopy, Int. Conf. on  Image Processing Theory, Tools and Applications (IPTA), pages 140-145, Paris, France, October 2014

  18. Maria Kholodtsova, Viktor Loschenov, Christian Daul, and Walter Blondel, Particle swarm optimisation algorithm for Monte Carlo-based inverse problem solving, Int. Conf. on Laser Optics, Saint Petersburg, Russia, June 30-July 4 2014 

  19. Maria Kholodtsova, Christian Daul, Marine Amouroux, Viktor Loschenov and Walter Blondel, Preprocessing method to improve optical parameters estimation in Monte Carlo-based inverse problem solving, SPIE Photonics Europe: Photonic Solutions for Better Health Care, Brussels, Belgium, April 2014

  20. Sharib Ali, Christian Daul, Thomas Weibel and Walter Blondel. Fast mosaicing of cystoscopic images from dense correspondence: combined SURF and TV-L1 optical flow method, IEEE Int. Conf. on Image Processing (ICIP), pages 1291-1295, Melbourne, Australia, 2013.

  21. Thomas Weibel, Christian Daul, Didier Wolf and Ronald Rösch, Contrast-enhancing seam detection and blending using graph cuts, 21st International Conference on Pattern Recognition (ICPR), pages 2732-2735, Tsukuba , Japan, November 11-15 2012.

  22. Nina Kalyagina, Tatiana Savelieva, Walter Blondel  Christian Daul, Didier Wolf and Viktor Loschenov. Endoscopic analysis of Diffuse-reflected light for bladder early cancer detection, 15th International Conference on Laser Optics, St Petersburg, Russia, June 25-29 2012

  23. Thomas Weibel, Christian Daul, Didier Wolf and Ronald Rösch. Planarity-enforcing higher-order graph cut, IEEE Int. Conf. on Image Processing (ICIP), pages 41-44, Bruxels, Belgium, 2011.

  24. Nina Kalyagina, Tatiana Savelieva, Viktor Loschenov.,Walter  Blondel, Christian Daul, and Didier Wolf. Analytical study of surface diffuse- reflectance signals from thin biological media, International School for Junior Scientists and Students on Optics, Laser Physics and Biophysics,  Saratov Fall Meeting (SFM'11) , Saratov, Russia, September 27-30 2011.

  25. Nina Kalyagina, Walter Blondel, Christian Daul, Tatiana Savelieva, Didier Wolf and Viktor  Loschenov. Diffuse-reflectance spectroscopic and imaging diagnostic methods for urinary bladder, 19th International Conference on Advanced Laser Technologies (ALT'), pages 38-39 Golden Sand,  Bulgaria, September 3-8 2011

  26. Thomas  Weibel, Christian Daul, Ronald Rösch and Didier Wolf, Endoscopic bladder image registration using sparse graph cuts. In 17th IEEE International Conference on Image Processing (ICIP), Hong-Kong, China, September 26-29, pages 157-160, 2010.

  27. Achraf Ben-Hamadou, Charles Soussen, Christian Daul, Walter Blondel and Didier Wolf,  Flexible projector calibration for active stereoscopic systems, In 17th IEEE International Conference on Image Processing (ICIP), Hong-Kong, China, September 26-29, pages 4241-4244, 2010.

  28. Achraf Ben-Hamadou, Christian Daul, Charles Soussen, Ahmed Rekik and  Walter  Blondel  A novel 3D surface construction approach: application to three-dimensional endoscopic data, In 17th IEEE International Conference on Image Processing (ICIP), Hong-Kong, China, September 26-29, pages 4425-4428, 2010.

  29. Nina Kalyagina, Victor Loschenov, Didier Wolf, Christian Daul and Walter Blondel. Experimental investigation and mathematical modelling of Diffuse Reflectance in thin biological layers, International School for Junior Scientists and Students on Optics, Laser Physics and Biophysics - Saratov Fall Meeting SFM'10, Saratov, Russie, October 2010.

  30. Nina Kalyagina, Viktor Loschenov, Didier Wolf., Christian Daul and Walter Blondel. Experimental investigation of diffuse reflectance imaging sensitivity to diffusing particle size changes in an optical model of bladder,  Advanced Laser Technologies Conference (ALT'10), Egmond aan Zee, Pays-Bas, September 11-16 2010.

  31. Christian Daul, Walter Blondel, Achraf Ben-Hamadou, Rosebet Miranda, Charles Soussen, Didier Wolf and François Guillemin. From 2D towards 3D cartography of hollow organs, 7th IEEE International Conference on Electrical Engineering, Computing Science and Automatic Control (CCE 2010), pages 285-293, Tuxtla Gutiérrez, Mexico, September 8-10 2010.

  32. Nina Kalyagina, Viktor Loschenov, Christian Daul, Didier Wolf and Walter Blondel, Development of a light diffusion investigation method in thin layers of biological tissues, Symposium on Laser Medical Applications (LMA'10), Russia, July 2010.

  33. Achraf Ben-Hamadou, Charles Soussen, Walter Blondel, Christian Daul and Didier Wolf. Comparative study of image registration techniques for bladder video-endoscopy, European Conference on Biomedical Optics (ECBO), Munich, Germany, June 14-18 2009. 

  34. Sophie Olijnyk, Yahir Hernandez-Mier, Walter Blondel, Christian Daul and  Didier Wolf, Combination of panoramic and fluorescence endoscopic images to obtain tumor spatial distribution information useful for bladder cancer detection, European Conferences on Biomedical Optics ECBO), Munich,  Germany  June 2007.

  35. Yahir Hernandez-Mier, Walter Blondel, Christian Daul, Didier Wolf, Geneviève Bourg-Heckly. 2-D panoramas from cystoscopic image sequences and potential application to fluorescence imaging, 6th IFAC Symposium on Modelling and Control in Biomedical Systems (MCBMS'06), pages 291-296, Reims, France,   September 2006. 

  36. Alain Tiedeu, Aude D. Kentsop, Christian Daul, Pierre Graebling and Martin Kom: Automated detection and classification of clusters of microcalcifications in mammograms. Proceedings of the 1st International Conference on Signal-Image Technology and Internet-Based Systems (SITIS), pages 15-20, Yaoundé, Cameroun, November 27 - December 1  2005

  37. Christian  Daul,Pierre Grabling and didier Wolf. Towards a 3D-Representation of microcalcification clusters using Images of Digital Mammographic Units, 2nd International Conference on Electrical and Electronics Engineering (ICEEE), pages 196-203, Mexico-City, September 2005. 

  38. Rosbet. Miranda, Walter Blondel, Christian. Daul, Yahir Hernandez-Mier and Didier Wolf. A simplified method of video-endoscopic image barrel distortion correction based on grey level registration. IEEE Int. Conf. on Image Processing (ICIP’04), pages 3383-3386, Singapore, 2004.

  39. Ruben Posada, Christian Daul, Didier Wolf and Pierre Aletti. Towards a fractioned treatment in conformal radiotherapy using 3D-multimodal data registration, Int. Conf. on Image Processing  (ICIP), pages 1911-1914, Singapore, October 24-27 2004.

  40. Gaëlle Valet, Stéphane. Sanchez, Juan Lopez, Christian Daul, Didier Wolf and Gilles Karcher. Towards a new diagnosis aid of cardiovascular diseases using 2D-multimodal data registration and 3D-data superimposition, IEEE Int. Conf. on Image Processing  (ICIP), pages 1907-1910, Singapore, October 24-27 2004.

  41. Rosbet Miranda, Yahir Hernandez-Mier, Christian Daul, Walter Blondel and Didier Wolf. Mosacing of medical video-endoscopic images : data quality improvement and algorithm testing. IEEE International Conference on Electrical and Electronics Engineering (ICEEE) and Tenth Conference on Electrical Engineering (CIE), Acapulco Guerrero, Mexico, September 2004.

  42. Didier Wolf, Stéphane Sanchez, Gaëlle Valet, Christian Daul, and Gilles Karcher. Epicardial contour segmentation as a basis of X-ray and SPECT-data superimposition. IEEE International Conference on Electrical and Electronics Engineering (ICEEE) and Tenth Conference on Electrical Engineering (CIE), Acapulco Guerrero, Mexico, September, 2004.

  43. Ruben Posada, Christian Daul, Didier Wolf, Rosbet Miranda,and Lorenzo Leija. Data down sampling for a fast registration of 3D-medical images in radiotherapy. IEEE International Conference on Electrical and Electronics Engineering (ICEEE) and  enth Conference on Electrical Engineering (CIE 2004), Acapulco Guerrero, Mexico, September 2004.

  44. Ruben Posada, Christian Daul, Didier Wolf, Pierre Aletti and Lorenzo Leija. Precise target localisation in conformal and fractioned radiotherapy. IEEE International Conference on Electrical and Electronics Engineering (ICEEE) and Tenth Conference on Electrical Engineering (CIE 2004), Acapulco Guerrero, Mexico, September 2004.

  45. Ruben Posada, Christian Daul and Didier Wolf, New frameless patient positioning algorithm in conformal radiotherapy using 3D-data registration, 25th Annual International Conference of the Engineering in Medecine and Biology Society (IEEE EMBS), Cancun, Mexico, September 17-21 2003.

  46. Stéphane Sanchez, Gaëlle Valet, Juan Lopez, Christian Daul, Didier Wolf and Gilles Karcher. 3D-superimposition of cardiac SPECT and coronarography data. 25th annual international conference of the Engineering in Medecine and Biology Society (IEEE-EMBS), Cancun, Mexique, 17-21 septembre 2003. 

  47. Stéphane Sanchez, Gaëlle Valet, Christian Daul, Didier Wolf and Gilles Karcher. Registration of cardiac tomoscintigraphy data and coronarogaphy data. 2nd European Medical and Biological Engineering Conference (EMBEC'02), Vienna,Austria, 4-8 December 2002.

  48. Pierre Graebling, Cyril Boucher, Christian Daul and Ernest Hirsch. 3D sculptured surface analysis using a structured light approach, Videometrics IV, Proc. SPIE vol. 2598, pages 128-139, Philadelphia, October 1995.

  49. Cyril Boucher, Christian Daul, Pierre Graebling and E. Hirsch. KBED: a Knowledge-Based Edge Detection System, Database and Expert Systems Applications, Norman Revell and A. Min Tjoa (Eds), Lecture Notes in Computer Science, vol. 978, Springer-Verlag, Berlin Heidelberg New-York, pages 344-353, 1995.