Liquid crystal spatial light modulator with optimized phase modulation ranges to display multiorder diffractive elements

Postprint (published version

First-order and multi-order diffractive lens using a device with 8P phase modulation range

Postprint (published version

Roadmap on optical security

Postprint (author's final draft

Industrias óseas musterienses en el cantábrico oriental: Los "alisadores" en hueso de los niveles B, C Y D de Axlor (Dima, Bizkaia)

Se presentan cuatro fragmentos de hueso, de los niveles de Paleolítico Medio de la cueva de Axlor, con huellas de uso en tareas repetitivas. Esos trabajos provocaron la abrasión y pulido de las zonas activas, lo que ha permitido su identificación como utillaje. Los objetos se han denominado "alisadores", a modo de hipótesis funcional. La naturaleza precisa de las labores realizadas no puede concretarse, en este estadio de la investigación, haciéndose necesaria la elaboración de un programa experimental específico. Para situar los materiales en su contexto, se ofrece en primer lugar una breve síntesis de los trabajos realizados en el yacimiento Musteriense de Axlor

Optical pattern recognition based on color vision models

A channel transformation based on opponent-color theory of the color vision models is applied to optical pattern recognition so that the conventional red, green, and blue (RGB) channels are transformed into bright-dark, red-green, and yellow-blue (ATD) channels. Matched filtering and correlation are performed over the new components of the target and the scene in the ATD system. The proposed transformation allows us to reduce the number of channels commonly used in color pattern recognition, passing from the three RGB channels to the two red-green and yellow-blue opponent-color channels

Resource location based on precomputed partial random walks in dynamic networks

The problem of finding a resource residing in a network node (the \emph{resource location problem}) is a challenge in complex networks due to aspects as network size, unknown network topology, and network dynamics. The problem is especially difficult if no requirements on the resource placement strategy or the network structure are to be imposed, assuming of course that keeping centralized resource information is not feasible or appropriate. Under these conditions, random algorithms are useful to search the network. A possible strategy for static networks, proposed in previous work, uses short random walks precomputed at each network node as partial walks to construct longer random walks with associated resource information. In this work, we adapt the previous mechanisms to dynamic networks, where resource instances may appear in, and disappear from, network nodes, and the nodes themselves may leave and join the network, resembling realistic scenarios. We analyze the resulting resource location mechanisms, providing expressions that accurately predict average search lengths, which are validated using simulation experiments. Reduction of average search lengths compared to simple random walk searches are found to be very large, even in the face of high network volatility. We also study the cost of the mechanisms, focusing on the overhead implied by the periodic recomputation of partial walks to refresh the information on resources, concluding that the proposed mechanisms behave efficiently and robustly in dynamic networks.Comment: 39 pages, 25 figure

Decide to Digitalize! Barriers, Drivers and the Entrepreneurial Cognition Perspective

This article introduces the special issue Decide to Digitalize! Barriers, Drivers and the Entrepreneurial Cognition Perspective. Nine research papers have been selected to reach two primary research aims: first, to understand how entrepreneurs, cognitively, make strategical decisions in order to be more competitive in the technology sector; second, to investigate how digital technologies and ICTs are being used in the context of SMEs and entrepreneurshi

De nuevo el asunto Avena ante la Corte Internacional de Justicia (CIJ): Los límites de la jurisdicción de la CIJ para determinar en un proceso de interpretación el incumplimiento de sus sentencias (y de sus consecuencias jurídicas)

El presente trabajo analiza los límites de la jurisdicción especial de la CIJ para determinar el incumplimiento de la sentencia Avena a raíz de la demanda de interpretación presentada por México tras la ejecución en Texas de su nacional, el Sr. Medellín Rojas, sin proveerle de la revisión judicial de su condena. Al declinar ejercer su competencia sobre la demanda mexicana, la CIJ nos recuerda que su jurisdicción sobre el fondo exige un grado de certeza más elevado que en fase preliminar, concluyendo que el objeto de la demanda concierne a una cuestión general, esto es, la relativa a los efectos de la sentencia Avena en el ordenamiento de Estados Unidos, y no al sentido y alcance del fallo, como exige el artículo 60 de su Estatuto. Esos mismos límites estatutarios han impedido que la CIJ atribuya a Estados Unidos la responsabilidad internacional derivada de la violación de la sentencia Avena, al entender que la ilicitud de las acciones de Texas es una cuestión relativa a la ejecución de la sentencia y no a su interpretación.The present work examines the limits on ICJ's special jurisdiction as to the determination of US' breach of the Avena Judgment, as a result of the request for interpretation filed by Mexico after its national, Mr. Medellín Rojas, had been executed in the State of Texas without having his conviction duly reviewed. Not acceding to Mexico's request, the ICJ recalls that its jurisdiction on the merits of the case requires a higher degree of certainty than the one required in the preliminary phase, and concludes that the object of the request concerns a general matter, that is to say, the legal effects of the Avena judgment on the US system, and not the scope and meaning of said judgment as provided in Article 60 of its Statute. Likewise, the constraints on its special jurisdiction hinders the ICJ from attributing international responsibility for Mr. Medellin's execution to the US, as a pronouncement on the unlawfulness of such actions applies to the enforcement of the judgment, not to its interpretation