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91.
92.
Images obtained with catadioptric sensors contain significant deformations which prevent the direct use of classical image treatments. Thus, Markov random fields (MRF) whose usefulness is now obvious for projective image processing, cannot be used directly on catadioptric images because of the inadequacy of the neighborhood. In this paper, we propose to define a new neighborhood for MRF by using the equivalence theorem developed for central catadioptric sensors. We show the importance of this adaptation for segmentation, image restoration and motion detection. 相似文献
93.
We propose a new encryption algorithm relying on reversible cellular automata (CA). The behavior complexity of CA and their
parallel nature makes them interesting candidates for cryptography. The proposed algorithm belongs to the class of symmetric
key systems.
Marcin Seredynski: He is a Ph.D. student at University of Luxembourg and Polish Academy of Sciences. He received his M.S. in 2004 from Faculty
of Electronics and Information Technology in Warsaw University of Technology. His research interests include cryptography,
cellular automata, nature inspired algorithms and network security. Currently he is working on intrusion detection algorithms
for ad-hoc networks.
Pascal Bouvry, Ph.D.: He earned his undergraduate degree in Economical & Social Sciences and his Master degree in Computer Science with distinction
(’91) from the University of Namur, Belgium. He went on to obtain his Ph.D. degree (’94) in Computer Science with great distinction
at the University of Grenoble (INPG), France. His research at the IMAG laboratory focussed on Mapping and scheduling task
graphs onto Distributed Memory Parallel Computers. Next, he performed post-doctoral researches on coordination languages and
multi-agent evolutionary computing at CWI in Amsterdam. He gained industrial experience as manager of the technology consultant
team for FICS in the banking sector (Brussels, Belgium). Next, he worked as CEO and CTO of SDC (Ho Chi Minh city, Vietnam)
in the telecom, semi-conductor and space industry. After that, He moved to Montreal Canada as VP Production of Lat45 and Development
Director for MetaSolv Software in the telecom industry. He is currently serving as Professor in the group of Computer Science
and Communications (CSC) of the Faculty of Sciences, Technology and Communications of Luxembourg University and he is heading
the Intelligent & Adaptive Systems lab. His current research interests include: ad-hoc networks & grid-computing, evolutionary
algorithms and multi-agent systems. 相似文献
94.
Pascal Nicolas Laurent Garcia Igor Stéphan Claire Lefèvre 《Annals of Mathematics and Artificial Intelligence》2006,47(1-2):139-181
In this work, we introduce a new framework able to deal with a reasoning that is at the same time non monotonic and uncertain. In order to take into account a certainty level associated to each piece of knowledge, we use possibility theory to extend the non monotonic semantics of stable models for logic programs with default negation. By means of a possibility distribution we define a clear semantics of such programs by introducing what is a possibilistic stable model. We also propose a syntactic process based on a fix-point operator to compute these particular models representing the deductions of the program and their certainty. Then, we show how this introduction of a certainty level on each rule of a program can be used in order to restore its consistency in case of the program has no model at all. Furthermore, we explain how we can compute possibilistic stable models by using available softwares for Answer Set Programming and we describe the main lines of the system that we have developed to achieve this goal. 相似文献
95.
Stroke Pattern Analysis and Synthesis 总被引:2,自引:0,他引:2
96.
Although particle detachment is a common phenomenon associated with most tribological processes, it seldom occurs that each piece of elemental debris can be considered as the result of a single event. Such an association has been revealed by the systematic study of a specific system, where a pin of graphite is made to rub against thoroughly polished steel. While the discontinuous nature of the transfer film allows a quantitative assessment of the volume of transfer h
e to be made by 3D optical-profilometry, the linear dependence of the rate of particle detachment dh
e/dn (n=number of rubbing cycles) with the logarithm of sliding speed v strongly suggests the existence of a particular type of stick–slip, where each stick may lead to the detachment of a debris particle. The variations in size of these debris with environment as revealed by AFM, further suggest that the global rate of particle detachment is of the form: dh
e/dn=Nx
i
, where N is the number of stick–slip events per rubbing cycle, x the proportion of stick events leading to a cohesive rupture, and
i
the mean volume of an elemental particle. While this relation is apparently supported by most experimental results, its actual validation can only be made by experiments at the level of single (nanoscale) asperities, carried out under well-controlled experimental conditions. 相似文献
97.
Light coupling into a sub-micrometer-thick waveguide is usually done through a grating coupler. Coupling efficiency is strongly enhanced by addition of a mirror above the grating. This new kind of coupler can be designed to achieve efficiencies as great as 80%. Numerical calculations for a high-angular-spread Gaussian incident beam are compared with experimental results obtained for a standard silicon-on-insulator waveguide. 相似文献
98.
The classical analysis of a conical corrugated horn is extended out of the balanced hybrid conditions using a vectorial multimodal Gaussian beam expansion. An experimental validation is also presented 相似文献
99.
BACKGROUND: Liposarcoma arising within a phyllodes tumor is extremely rare. To the best of our knowledge, a malignant phyllodes tumor with liposarcomatous stroma diagnosed by fine needle aspiration (FNA) has not been reported before. CASE: A 39-year-old female had a malignant phyllodes tumor with liposarcomatous stroma diagnosed by FNA cytology. Two subtypes of liposarcomatous stroma, including lipomalike differentiated and myxoid, were found in the aspirates. The cytologic findings were very representative of the histologic features. CONCLUSION: It is very important to recognize the cytologic features of such rare tumors. An accurate diagnosis preoperatively by FNA permits better therapy planning. 相似文献
100.
We are presenting a fast new method of analysing a dielectric interface which is assumed to be cylindrically symmetrical. It is based on a multimode Gaussian beam development. Then two different cases are considered and we show the kind of results we can expect from this process. Finally, we explain in detail the relationships between the paraxial approximation and further justified simplifications which lead to an important calculation time decrease. 相似文献