14987889
Optimal Camera Parameter Selection for State Estimation with Applications in Object Recognition
In this paper we introduce a formalism for optimal camera parameter selection for iterative state estimation. We consider a framework based on Shannon's information theory and select the camera parameters that maximize the mutual information, i.e. the information that the captured image conveys about the true state of the system. The technique explicitly takes into account the a priori probability governing the computation of the mutual information. Thus, a sequential decision process can be formed by treating the a posteriori probability at the current time step in the decision process as the a priori probability for the next time step. The convergence of the decision process can be proven. 
 
We demonstrate the benefits of our approach using an active object recognition scenario. The results show that the sequential decision process outperforms a random strategy, both in the sense of recognition rate and number of views necessary to return a decision.
6978911
Information Theoretic Sensor Data Selection for Active Object Recognition and State Estimation
We introduce a formalism for optimal sensor parameter selection for iterative state estimation in static systems. Our optimality criterion is the reduction of uncertainty in the state estimation process, rather than an estimator-specific metric (e.g., minimum mean squared estimate error). The claim is that state estimation becomes more reliable if the uncertainty and ambiguity in the estimation process can be reduced. We use Shannon's information theory to select information-gathering actions that maximize mutual information, thus optimizing the information that the data conveys about the true state of the system. The technique explicitly takes into account the a priori probabilities governing the computation of the mutual information. Thus, a sequential decision process can be formed by treating the a priori probability at a certain time step in the decision process as the a posteriori probability of the previous time step. We demonstrate the benefits of our approach in an object recognition application using an active camera for sequential gaze control and viewpoint selection. We describe experiments with discrete and continuous density representations that suggest the effectiveness of the approach.
16390848
A Fully Projective Formulation to Improve the Accuracy of Lowe's Pose-Estimation Algorithm
Both the original version of David Lowe's influential and classic algorithm for tracking known objects and a reformulation of it implemented by Ishiiet al. rely on (different) approximated imaging models. Removing their simplifying assumptions yields a fully projective solution with significantly improved accuracy and convergence, and arguably better computation-time properties.
34334066
Haptics in augmented reality
An augmented reality system merges synthetic sensory information into a user's perception of a three-dimensional environment. An important performance goal for an augmented reality system is that the user perceives a single seamless environment. In most augmented reality systems the user views a real world augmented only with visual information and is not provided with a means to interact with the virtual objects. We describe an augmented reality system that, in addition to visual augmentation, merges synthetic haptic input into the user's perception of the real environment. Our system uses a PHANToM/sup TM/ haptic interface device to generate the haptic sensory input in real-time. The system allows user interactions such as moving or lifting a virtual object, and demonstrates interactions between virtual and real objects. Methods to provide proper visual occlusion between real and virtual objects are also described.
13531439
Combining Type Theory and Untyped Set Theory
We describe a dependent type theory with proof irrelevance. Within this framework, we give a representation of a form of Mac Lane set theory and discuss automated support for constructing proofs within this set theory. One of the novel aspects of the representation is that one is allowed to use any class (in the set theory) as a type (in the type theory). Such class types allow a natural way of representing partial functions (e.g., the first and second operators on the class of Kuratowski ordered pairs). We also discuss how automated search can be used to construct proofs. In particular, the first-order prover Vampire can be called to solve a challenge problem (the injective Cantor Theorem) which is notoriously difficult for higher-order automated provers.
529377
Encoding Functional Relations in Scunak
We describe how a set-theoretic foundation for mathematics can be encoded in the new system Scunak. We then discuss an encoding of the construction of functions as functional relations in untyped set theory. Using the dependent type theory of Scunak, we can define object level application and lambda abstraction operators (in the spirit of higher-order abstract syntax) mediating between functions in the (meta-level) type theory and (object-level) functional relations. The encoding has also been exported to Automath and Twelf.
27008190
Tutorial: Using TPS for Higher-Order Theorem Proving and ETPS for Teaching Logic
TPS is an automated theorem proving system which can be used to prove theorems of first- or higher-order logic automatically, interactively, or in a combination of these modes of operation. Proofs in TPS are presented in natural deduction style. ETPS is a program which was obtained from TPS by deleting all the facilities for proving theorems automatically. ETPS can be used by students to learn how to prove theorems interactively. The objective of the tutorial is to teach participants how to make effective use of TPS and ETPS.
3260299
The Protein Non-Folding Problem: Amino Acid Determinants of Intrinsic Order and Disorder
To investigate the determinants of protein order and disorder, three primary and one derivative database of intrinsically disordered proteins were compiled. The segments in each primary database were characterized by one of the following: X-ray crystallography, nuclear magnetic resonance (NMR), or circular dichroism (CD). The derivative database was based on homology. The three primary disordered databases have a combined total of 157 proteins or segments of length.30 with 18,010 residues, while the derivative database contains 572 proteins from 32 families with 52,688 putatively disordered residues. For the four disordered databases, the amino acid compositions were compared with those from a database of ordered structure. Relative to the ordered protein, the intrinsically disordered segments in all four databases were significantly depleted in W, C, F, I, Y, V, L and N, significantly enriched in A, R, G, Q, S, P, E and K, and inconsistently different in H, M, T, and D, suggesting that the first set be called order-promoting and the second set disorder-promoting. Also, 265 amino acid properties were ranked by their ability to discriminate order and disorder and then pruned to remove the most highly correlated pairs. The 10 highest-ranking properties after pruning consisted of 2 residue contact scales, 4 hydrophobicity scales, 3 scales associated with.-sheets and one polarity scale. Using these 10 properties for comparisons of the 3 primary databases suggests that disorder in all 3 databases is very similar, but with those characterized by NMR and CD being the most similar, those by CD and X-ray being next, and those by NMR and X-ray being the least similar.
12173886
VR-VIBE: A Virtual Environment for Co-operative Information Retrieval
We present a virtual reality application called VR-VIBE which is intended to support the co-operative browsing and filtering of large document stores. VR-VIBE extends a visualisation approach proposed in a previous two dimensional system called VIBE into three dimensions, allowing more information to be visualised at one time and supporting more powerful styles of interaction, The essence of VR-VIBE is that multiple users can explore the results of applying several simultaneous queries to a corpus of documents. By arranging the queries into a spatial framework, the system shows the relative attraction of each document to each query by its spatial position and also shows the absolute relevance of each document to all of the queries. Users may then navigate the space, select individual documents, control the display according to a dynamic relevance threshold and dynamically drag the queries to new positions to see the effect on the document space. Co-operative browsing is supported by directly embodying users and providing them with the ability to interact over live audio connections and to attach brief textual annotations to individual documents. Finally, we conclude with some initial observations gleaned from our experience of constructing VR-VIBE and using it in the laboratory setting.