Romanian Academy

About: Romanian Academy is a archive organization based out in Bucharest, Romania. It is known for research contribution in the topics: Population & Nonlinear system. The organization has 3662 authors who have published 10491 publications receiving 146447 citations. The organization is also known as: Academia Română & Societatea Literară Română.

Mechanical properties and biocompatibility of the sputtered Ti doped hydroxyapatite.

Abstract: The hydroxyapatite enriched with Ti were prepared as possible candidates for biomedical applications especially for implantable devices that are in direct contact to the bone. The hydroxyapatites with different Ti content were prepared by RF magnetron sputtering on Ti-6Al-4V alloy using pure hydroxyapatite and TiO2 targets. The content of Ti was modified by changing the RF power fed on TiO2 target. The XPS and FTIR analyses revealed the presence of hydroxyapatite structure. The hardness and elastic modulus of the hydroxyapatite were increased by Ti addition. After 5 days of culture, the cell viability of the Ti-6Al-4V was enhanced by depositing with undoped or doped hydroxyapatite. The Ti additions led to an increase in cell viability of hydroxyapatite, after 5 days of culture. The electron microscopy showed the presence of more cells on the surface of Ti-enriched hydroxyapatite than those observed on the surface of the uncoated alloys or undoped hydroxyapatite.

Action from Still Image Dataset and Inverse Optimal Control to Learn Task Specific Visual Scanpaths

Abstract: Human eye movements provide a rich source of information into the human visual information processing. The complex interplay between the task and the visual stimulus is believed to determine human eye movements, yet it is not fully understood, making it difficult to develop reliable eye movement prediction systems. Our work makes three contributions towards addressing this problem. First, we complement one of the largest and most challenging static computer vision datasets, VOC 2012 Actions, with human eye movement recordings collected under the primary task constraint of action recognition, as well as, separately, for context recognition, in order to analyze the impact of different tasks. Our dataset is unique among the eyetracking datasets of still images in terms of large scale (over 1 million fixations recorded in 9157 images) and different task controls. Second, we propose Markov models to automatically discover areas of interest (AOI) and introduce novel sequential consistency metrics based on them. Our methods can automatically determine the number, the spatial support and the transitions between AOIs, in addition to their locations. Based on such encodings, we quantitatively show that given unconstrained read-world stimuli, task instructions have significant influence on the human visual search patterns and are stable across subjects. Finally, we leverage powerful machine learning techniques and computer vision features in order to learn task-sensitive reward functions from eye movement data within models that allow to effectively predict the human visual search patterns based on inverse optimal control. The methodology achieves state of the art scanpath modeling results.

Generalized Diagonal Crossed Products and Smash Products for Quasi-Hopf Algebras. Applications

Abstract: In this paper we introduce generalizations of diagonal crossed products, two-sided crossed products and two-sided smash products, for a quasi-Hopf algebra H. The results we obtain may then be applied to H *-Hopf bimodules and generalized Yetter-Drinfeld modules. The generality of our situation entails that the “generating matrix” formalism cannot be used, forcing us to use a different approach. This pays off because as an application we obtain an easy conceptual proof of an important but very technical result of Hausser and Nill concerning iterated two-sided crossed products.