We All Live in a Virtual Submarine
Our seas and oceans hide a plethora of archaeological sites such as ancient shipwrecks that, overtime, are being destroyed through activities such as deepwater trawling and treasure hunting. In 2006, a multidisciplinary team of 11 European institutions established the Venus (Virtual Exploration of Underwater Sites) consortium to make underwater sites more accessible by generating thorough, exhaustive 3D records for virtual exploration. Over the past three years, we surveyed several shipwrecks around Europe and investigated advanced techniques for data acquisition using both autonomous and remotely operated vehicles coupled with innovative sonar and photogrammetric equipment. Access to most underwater sites can be difficult and hazardous owing to deep waters. However, this same inhospitable environment offers extraordinary opportunities to archaeologists because darkness, low temperatures, and low oxygen rates are all favorable to preservation. From a visualization pipeline perspective, this project had two main challenges. First, we had to gather large amounts of raw data from various sources. Then, we had to develop techniques to filter, calibrate, and map the data and then bring it all together into a single accurate visual representation.
Real-time reconstruction of underwater environments: From 2D to 3D
This paper presents a real-time 2D image mosaicking tool developed to provide instantaneous feedback on image quality and area coverage during underwater site inspection or documentation surveys. The algorithm implements a feature extraction and matching approach to stitching video frames into a single image. While its main advantage is providing good results for fast documentation in real-time even on low-end computer hardware, it has also some limitations in terms of sensitivity to the camera motion and lower performance in textureless or uniform environments. The final part of the paper addresses those limitations by providing an insight of the concept behind the ongoing development of a real-time direct 3D reconstruction tool for underwater applications.
Symbolic and Quantitative Approaches to Reasoning with Uncertainty
Invited Papers.- Qualitative Decision Rules under Uncertainty.- Applications of Latent Class Analysis in Social Science Research.- Foundations of Uncertainty Concepts.- Transformations from Imprecise to Precise Probabilities.- A Representation Theorem and Applications.- On Modal Probability and Belief.- Bayesian Networks.- A Multi-layered Bayesian Network Model for Structured Document Retrieval.- Using Kappas as Indicators of Strength in Qualitative Probabilistic Networks.- Qualitative Bayesian Networks with Logical Constraints.- Introducing Situational Influences in QPNs.- Classification of Aerial Missions Using Hidden Markov Models.- Algorithms for Uncertainty Inference.- Dynamic Importance Sampling Computation in Bayesian Networks.- Morphing the Hugin and Shenoy-Shafer Architectures.- Learning.- Characterization of Inclusion Neighbourhood in Terms of the Essential Graph: Upper Neighbours.- Approximating Conditional MTE Distributions by Means of Mixed Trees.- Effective Dimensions of Partially Observed Polytrees.- Decision Graphs.- Applying Numerical Trees to Evaluate Asymmetric Decision Problems.- Mixed Influence Diagrams.- Decision Making Based on Sampled Disease Occurrence in Animal Herds.- Decision Network Semantics of Branching Constraint Satisfaction Problems.- Belief Functions.- Web of Trust: Applying Probabilistic Argumentation to Public-Key Cryptography.- A Comparison of Methods for Transforming Belief Function Models to Probability Models.- Fuzzy Matching and Evidential Reasoning.- Modeling Positive and Negative Pieces of Evidence in Uncertainty.- Directed Evidential Networks with Conditional Belief Functions.- Computational-Workload Based Binarization and Partition of Qualitative Markov Trees for Belief Combination.- Risk Assessment in Drinking Water Production Using Belief Functions.- Algebraic Structures Related to the Consensus Operator for Combining of Beliefs.- Fuzzy Sets.- Inclusion Measures in Intuitionistic Fuzzy Set Theory.- A Random Set Model for Fuzzy Labels.- On the Induction of Different Kinds of First-Order Fuzzy Rules.- Reasoning under Vagueness Expressed by Nuanced Statements.- Possibility Theory.- Partial Lattice-Valued Possibilistic Measures and Some Relations Induced by Them.- Coherent Conditional Probability as a Measure of Uncertainty of the Relevant Conditioning Events.- Decision Trees and Qualitative Possibilistic Inference: Application to the Intrusion Detection Problem.- Default Reasoning.- Multi-valued Conditional Events Avoid Lewis' Triviality Result.- Solving Semantic Problems with Odd-Length Cycles in Argumentation.- On the Relation between Reiter's Default Logic and Its (Major) Variants.- Belief Revision and Inconsistency Handling.- Probable Consistency Checking for Sets of Propositional Clauses.- On Iterated Revision in the AGM Framework.- Epistemic Logics for Information Fusion.- Logics.- Propositional Fusion Rules.- Preferential Logics for Reasoning with Graded Uncertainty.- Paraconsistent Reasoning via Quantified Boolean Formulas, II: Circumscribing Inconsistent Theories.- Modal (Logic) Paraconsistency.- A Formal Framework for Handling Conflicting Desires.- A Sequent Calculus for Skeptical Reasoning in Predicate Default Logic (Extended Abstract).- Probabilistic Lexicographic Entailment under Variable-Strength Inheritance with Overriding.- Demo Papers.- ABEL: An Interactive Tool for Probabilistic Argumentative Reasoning.- The Hugin Tool for Learning Bayesian Networks.