Miguel Sainz - Academia.edu (original) (raw)

Papers by Miguel Sainz

Lecture Notes in Mathematics, 2013

or c 2 (1 − αt) ≤ c 1 ≤ c 2 (1 + αt) or c 1 (1 − αt) ≤ c 2 ≤ c 1 (1 + αt) ⇒ // la primera condici... more or c 2 (1 − αt) ≤ c 1 ≤ c 2 (1 + αt) or c 1 (1 − αt) ≤ c 2 ≤ c 1 (1 + αt) ⇒ // la primera condició implica c 1 ≤ c 2 (1 + αt) i c 1 (1 − αt) ≤ c 2 ⇒ c 1 ≤ c 2 (1 + αt) or c 1 (1 − αt) ≤ c 2 ⇒ // la primera d'aquestes condicions implica la segona ⇒ c 1 (1 − αt) ≤ c 2. ⇐) Suposem c 1 (1 − αt) ≤ c 2. Podem considerar dues situacions • c 1 < c 2 i per tant, X 1 ≤ X 2. • c 1 ≥ c 2 i per tant, c 1 (1 − αt) ≤ c 2 ≤ c 1 ⇒ X 1 ≈ α X 2. 2. ⇒) X 1 4 α X 2 ⇔ ⇔ X 1 ≤ X 2 or X 1 ≈ α X 2 ⇔ ⇔ c 1 ≤ c 2 or c 2 (1 + αt) ≤ c 1 ≤ c 2 (1 − αt) or c 1 (1 + αt) ≤ c 2 ≤ c 1 (1 − αt) ⇒ // la primera condició implica c 1 ≤ c 2 (1 − αt) i c 1 (1 + αt) ≤ c 2 ⇒ c 1 ≤ c 2 (1 − αt) or c 1 (1 + αt) ≤ c 2 ⇒ // la segona d'aquestes condicions implica la primera ⇒ c 1 ≤ c 2 (1 − αt). ⇐) Suposem c 1 ≤ c 2 (1 − αt). Podem considerar dues situacions

Lecture Notes in Mathematics, 2013

The problem discussed in this chapter is that of obtaining a class of interval functions \(F: {I}... more The problem discussed in this chapter is that of obtaining a class of interval functions \(F: {I}^{{\ast}}({\mathbb{R}}^{k}) \rightarrow {I}^{{\ast}}(\mathbb{R})\), consistently referring to the continuous functions f from \({\mathbb{R}}^{k}\) to \(\mathbb{R}\).

A sailboat can be described by a system of nonlinear differential equations. A polar speed diagra... more A sailboat can be described by a system of nonlinear differential equations. A polar speed diagram shows the set of all feasible speed that can be reached for different values of the orientation angle of the boat, in a permanent regime. This paper shows how interval analysis can be used to characterize the polar speed diagram in a reliable way. , (vi) ω = ( −r s cos δ s )f s −r r cos δ r f r −α θ ω J

In one hand, automatic generation of models from a set of positive and negative samples and a a-p... more In one hand, automatic generation of models from a set of positive and negative samples and a a-priori knowledge (if available) is a crucial issue for pattern recognition applications. In the other hand, a generic multipurpose 2D object model representation is very useful in object recognition in complex scenes. In this paper we present a new approach of 2D objects multi-purpose model representation based in context sensitive languages and automatic learning. To illustrate the model representation and the performances achieved two different applications have been developed: an outdoor traffic sign identifier and a human face identifier. Partial results of the recognition process of both applications are shown.

In this paper we present a novel and efficient depth- image representation and warping technique ... more In this paper we present a novel and efficient depth- image representation and warping technique based on a piece-wise linear approximation of the depth-image as a textured and simplified triangle mesh. We describe the application of a hierarchical triangulation method to gener- ate view-dependent triangulated depth-meshes efficiently from reference depth-images, and propose a new hardware accelerated depth-image rendering technique that

Reliable Computing

This paper summarizes the most important results and features of Modal Interval Analysis. The gro... more This paper summarizes the most important results and features of Modal Interval Analysis. The ground idea of Interval mathematics is that ordinary set-theoretical intervals are the consistent context for numerical computing. However, this interval context presents basic structural and semantic rigidity arising from its set-theoretical foundation. To correct this situation, Modal Interval Analysis defines intervals starting from the identification of

Interval models may be used in many cases to express the imprecision and the uncertainty related ... more Interval models may be used in many cases to express the imprecision and the uncertainty related to complex systems. The envelopes may be used to represent the results of the simulation of these models. One of the applications of the envelopes is as reference behaviour for Fault Detection (FD) based on analytical redundancy. In this case, the properties of the envelopes (completeness, soundness) have important consequences on the results of the FD, like missed or false alarms. This paper presents the Modal Interval Simulator (MIS), which approaches the FD problem by means of errorbounded envelopes, i.e. by the simultaneous computation of an overbounded envelope and an underbounded one. Modal Interval Analysis, which provides tools to compute interval extensions of real functions with the adequate semantics, is used for computing these envelopes. The MIS system uses multiple sliding time windows for performing FD. This allows the detection of faults of different kinds avoiding (provided that some assumptions are fulfilled) false alarms.

Resumen. La necesidad de tratar con la incertidumbre es una constante en todos los campos de la i... more Resumen. La necesidad de tratar con la incertidumbre es una constante en todos los campos de la ingeniería. El análisis intervalar [1] es una metodología innovadora que nos permite considerar la incertidumbre de las variables como intervalos de indeterminación e incorporarla en los modelos numéricos. Dicho análisis puede ser aplicado juntamente con los elementos ﬁnitos - "Interval Finite Element Method"[2], con los que el cálculo de estructuras se hace de un modo mas robusto [3]. En este artículo se presentan algunas aplicaciones de esta metodología en problemas de ingeniería civil. En estas aplicaciones se consideraran las incertidumbres físicas y del material.

An interval model can express the imprecision and the uncertainty associated to the modeling of a... more An interval model can express the imprecision and the uncertainty associated to the modeling of a system. The result of the simulation of one of these models can be represented in the form of envelope trajectories. These envelopes can be characterized by several properties such as completeness or soundness, that lead to the concepts of overbounded and underbounded envelopes. The simulation of such interval models can be performed by several means including qualitative, semiqualitative and quantitative methods. A brief description of the different types of simulators is presented and their respective properties are outlined and compared in relation to model-based fault detection. Whereas the existing simulators do not provide any information about the "error" with respect to the exact envelope, a method to obtain error-bounded envelopes is proposed. It is based on the simultaneous computation of an underbounded and an overbounded envelope by means of Modal Interval Analysis...

The uncertainty related to complex systems may be expressed in many cases by interval models. The... more The uncertainty related to complex systems may be expressed in many cases by interval models. The results of the simulation of these models may be represented by envelopes. One application of envelopes is as reference behaviour for Fault Detection (FD) based on analytical redundancy. Therefore, the properties of the envelopes (completeness, soundness) have important consequences on the results of the FD, like missed or false alarms.

Résumé/Abstract In this paper, interval arithmetic is introduced to study plants with non-linear ... more Résumé/Abstract In this paper, interval arithmetic is introduced to study plants with non-linear parametric perturbations. Common robustness problems as stability or performance analysis are reduced to the evaluation of interval functions. A new methodology of handling interval functions is introduced and applied to robustness analysis. Fast zero inclusion/exclusion algorithms are introduced in order to be applied into robust control design procedures.

Imprecision and uncertainty in systems can often be expressed with interval models. Simulation of... more Imprecision and uncertainty in systems can often be expressed with interval models. Simulation of these models, known as semiqualitative simulation, produces envelopes. These envelopes can be characterised by several properties such as completeness, soundness; they can be overbounded or underbounded. Simulation of such interval models can be performed by several means including quantitative, qualitative and semiqualitative simulators. A brief description of the different types of simulators is presented and their respective properties are outlined and compared. It is shown that all of them obtain unknown-error envelopes and a method to obtain known-error envelopes is proposed. It is based on simultaneous computation of an underbounded and an overbounded envelope. The overbounded envelope is computed by means of Modal Interval Analysis. Two methods to control the envelopes' error are proposed: the first one is based on tightening the overbounded envelope whereas the second on wid...

With the popularity of points as graphics primitives, it is important to handle large-scale point... more With the popularity of points as graphics primitives, it is important to handle large-scale point sets that exceed avail-able in-core (main) memory. In particular, high-perfor-mance level-of-details (LODs) visualization from out-of-core is a challenging problem. In this context we present a novel point-splatting approach, short XSplat, that breaks the main memory barrier. It is based on a paginated multiresolution point hierarchy and virtual memory map-ping. The main contributions are a novel block-based sequential multiresolution point hierarchy, an efficient LOD-block paging mechanism and dynamic mapping into video-cache. XSplat is scalable by using sequentialized data structures, and it seamlessly bridges the disk-, main-and video-memory sub-systems. Experiments demonstrate the quality and efficiency that is achieved by XSplat.

Lecture Notes in Mathematics, 2013

Reliable Computing