Multiple object manipulation: is structural modularity necessary? A study of the MOSAIC and CARMA models

International audienceA model that tackles the Multiple Object Manipulation task computationally solves a higly complex cognitive task. It needs to learn how to identify and predict the dynamics of various physical objects in different contexts in order to manipulate them. MOSAIC is a model based on the modularity hypothesis: it relies on multiple controllers, one for each object. In this paper we question this modularity characteristic. More precisely, we show that the MOSAIC convergence during learning is quite sensitive to parameter values. To solve this issue, we define another model (CARMA) which tackles the manipulation problem with a single controller. We provide experimental and theoretical evidence that tend to indicate that non-modularity is the most natural hypothesis

Towards a Platform-Independent Cooperative Human Robot Interaction System: III. An Architecture for Learning and Executing Actions and Shared Plans

Robots should be capable of interacting in a cooperative and adaptive manner with their human counterparts in open-ended tasks that can change in real-time. An important aspect of the robot behavior will be the ability to acquire new knowledge of the cooperative tasks by observing and interacting with humans. The current research addresses this challenge. We present results from a cooperative human-robot interaction system that has been specifically developed for portability between different humanoid platforms, by abstraction layers at the perceptual and motor interfaces. In the perceptual domain, the resulting system is demonstrated to learn to recognize objects and to recognize actions as sequences of perceptual primitives, and to transfer this learning, and recognition, between different robotic platforms. For execution, composite actions and plans are shown to be learnt on one robot and executed successfully on a different one. Most importantly, the system provides the ability to link actions into shared plans, that form the basis of human-robot cooperation, applying principles from human cognitive development to the domain of robot cognitive systems. © 2009-2011 IEEE

The relationship between corporate governance mechanisms and firm value: evidence from the largest Australian firms

The mixed findings in the literature pertaining to the relationship between corporate governance mechanisms and firm value have resulted in the endogeneity issue of the former becoming central to discussions in corporate governance and corporate finance studies. As endogeneity can be in the form of reverse causality and/or in a dynamic sense, this thesis examines the relationships between corporate governance mechanisms that are proxied by ownership concentration and debt and firm value in the largest Australian firms from 1997 to 2008. The study investigates this issue through three different tests. First, the study examines whether there are any causal relationships between ownership concentration, debt and firm value. Second, the study investigates whether ownership concentration, debt and firm value are best treated as a group in order to assess their influence on each other. Therefore, the study assesses their substitutability or complementarity. Third, the study examines whether there are any non-linear relationships between ownership concentration and firm value on the one hand and debt on the other hand, as well as between debt and firm value. In investigating the dynamic endogeneity issue through these tests, the study employs two methodologies: two-way fixed effects (FE) and the two-step system generalised method of moments (GMM). In the first test, the study finds a causal relationship between ownership concentration and firm value as well as between debt and firm value. The causality is found to run from firm value to ownership concentration in a negative direction and from debt to firm value also in a negative direction. No causal relationship is found between ownership concentration and debt. However, further investigation by using sub-samples of ownership concentration reveals that there is causality between these two corporate governance mechanisms. It is found that causality runs from ownership concentration to debt in a negative direction. This test finds that firm value causes ownership concentration, thus providing evidence that endogeneity in the form of reverse causality exists. However, in the dynamic sense, it is found that dynamic endogeneity is not an issue in this test. The second test discovers that there is no evidence that ownership concentration, debt and firm value are effective as a group. Therefore, the study fails to identify their substitutability or complementarity. Furthermore, this test finds that dynamic endogeneity is not an issue in influencing ownership concentration, debt and firm value when they are tested as a group. In the final test, the study finds that there is a non-linear relationship between ownership concentration and firm value. This non-linear association is found to have an influence on the non-linearity between ownership concentration and debt. Further, the study also finds that debt and firm value are non-linear. It is found that the dynamic endogeneity issue does influence the non-linearity functions of ownership concentration but not the non-linearity functions of debt. The thesis concludes that dynamic endogeneity is not a serious issue in influencing the relationship between corporate governance mechanisms and firm value in the largest Australian firms

Artificial Cognition for Social Human-Robot Interaction: An Implementation

© 2017 The Authors Human–Robot Interaction challenges Artificial Intelligence in many regards: dynamic, partially unknown environments that were not originally designed for robots; a broad variety of situations with rich semantics to understand and interpret; physical interactions with humans that requires fine, low-latency yet socially acceptable control strategies; natural and multi-modal communication which mandates common-sense knowledge and the representation of possibly divergent mental models. This article is an attempt to characterise these challenges and to exhibit a set of key decisional issues that need to be addressed for a cognitive robot to successfully share space and tasks with a human. We identify first the needed individual and collaborative cognitive skills: geometric reasoning and situation assessment based on perspective-taking and affordance analysis; acquisition and representation of knowledge models for multiple agents (humans and robots, with their specificities); situated, natural and multi-modal dialogue; human-aware task planning; human–robot joint task achievement. The article discusses each of these abilities, presents working implementations, and shows how they combine in a coherent and original deliberative architecture for human–robot interaction. Supported by experimental results, we eventually show how explicit knowledge management, both symbolic and geometric, proves to be instrumental to richer and more natural human–robot interactions by pushing for pervasive, human-level semantics within the robot's deliberative system

Vers une théorie de la coopération incarnée, distribuée et computationelle

Robots will gradually integrate our homes wielding the role of companions, humanoids ornot. In order to cope with this status they will have to adapt to the user, especially bylearning knowledge or skills from him that they may lack. In this context, their interactionshould be natural and evoke the same cooperative mechanisms that humans use. At thecore of those mechanisms is the concept of action: what is an action, how do humansrecognize them, how they produce or describe them? The modeling of aspects of thesefunctionalities will be the basis of this thesis and will allow the implementation of higherlevel cooperative mechanisms. One of these is the ability to handle “shared plans” whichallow two (or more) individuals to cooperate in order to reach a goal shared by all.Throughout the thesis I will attempt to make links between the human development ofthese capabilities, their neurophysiology, and their robotic implementation. As a result ofthis work, I will present a fundamental difference between the representation of knowledgein humans and machines, still in the framework of cooperative interaction: the possibledissociation of a robot body and its cognition, which is not easily imaginable for humans.This dissociation will lead me to explore the “shared experience framework, a situationwhere a central artificial cognition manages the shared knowledge of multiple beings, eachof them owning some kind of individuality. In the end this phenomenon will interrogate thevarious philosophies of mind by asking the question of the attribution of a mind to amachine and the consequences of such a possibility regarding the human mind.Les robots vont peu à peu intégrer nos foyers sous la forme d’assistants et de compagnons,humanoïdes ou non. Afin de remplir leur rôle efficacement ils devront s’adapter àl’utilisateur, notamment en apprenant de celui-ci le savoir ou les capacités qui leur fontdéfaut. Dans ce but, leur manière d’interagir doit être naturelle et évoquer les mêmesmécanismes coopératifs que ceux présent chez l’homme. Au centre de ces mécanisme setrouve le concept d’action : qu’est-ce qu’une action, comment les humains les reconnaissent,comment les produire ou les décrire ? La modélisation de toutes ces fonctionnalitésconstituera la fondation de cette thèse et permettra la mise en place de mécanismescoopératifs de plus haut niveau, en particulier les plan partagés qui permettent à plusieursindividus d’oeuvrer de concert afin d’atteindre un but commun. Finalement, je présenteraiune différence fondamentale entre la représentation de la connaissance chez l’homme etchez la machine, toujours dans le cadre de l’interaction coopérative : la dissociation possibleentre le corps d’un robot et sa cognition, ce qui n’est pas imaginable chez l’homme. Cettedissociation m’amènera notamment à explorer le « shared experience framework », unesituation dans laquelle une cognition artificielle centrale gère l’expérience partagée demultiples individus ayant chacun une identité propre. Cela m’amènera finalement àquestionner les différentes philosophies de l’esprit du point de vue de l’attribution d’unesprit à une machine et de ce que cela impliquerai quant à l’esprit humain

EFAA: a companion emerges from integrating a layered cognitive architecture

Presentat a: the 2014 ACM/IEEE International Conference on Human-Robot Interaction (HRI 2014), celebrat del 3 al 6 de març de 2014 a Bielefeld, Alemanya.In this video, we present the human robot interaction generated by applying the DAC cognitive architecture [1] on the iCub robot. We demonstrate how the robot reacts and adapts to its environment within the context a continuous interactive scenario including different games. We emphasize as well that the artificial agent is maintaining a self-model in terms of emotions and drives and how those are expressed in order affect the social interaction.This work is supported by the EU FP7 project EFAA (FP7-ICT- 270490) and by the Spanish Plan Nacional TIN2010-16745 (FAA-Arquitectura Cognitiva Biomimetica para un Funcional Ayudante de Androide Socialmente en Activo)

Péptido antimicrobiano AP7121: inhibición de adhesión bacteriana en catéteres vasculares: Péptido antimicrobiano AP7121 en catéteres

Healthcare-associated bloodstream infections are the leading cause of morbidity and mortality in hospitalized patients. Vascular catheter-related infection is its main source. Gram-positive bacteria especially Staphylococcus spp., are the most prevalent etiological agents. The aim was to assess the inhibitory activity of the AP7121 on the Staphylococcus aureus adherence in vascular catheters. The biofilm-producer strain S. aureus ATCC 35556 (SA) was used. MIC AP7121 for SA was performed. 20 mm segments of the vascular catheter (n=3) were inoculated with 104 UFC mL-1 of SA. Three different treatment schemes (A: simultaneous, B: previous, and C: following bacterial challenge) using 1 x MIC AP7121 were tested. Control groups were included in each scheme. The MICAP7121 was 0.48 mg/L. A reduction of 2log10 representing a decrease of 99 % of viable SA cells was achieved with schemes A and B. The post-challenge treatment with AP7121 (scheme C) produced a reduction of 1log10 representing a decrease of 90 % of viable SA cells. The results observed in this work suggest a fast antimicrobial activity of AP7121 that could be beneficial to reduce bacterial adherence on medical devices such as vascular cathetersLas infecciones del torrente sanguíneo asociadas a los cuidados de la salud constituyen una de las principales causas de morbilidad y mortalidad. La infección relacionada con catéteres vasculares es su fuente principal. Las bacterias Gram positivas, especialmente Staphylococcus spp., constituyen uno de los agentes etiológicos más frecuentes. Objetivo: evaluar la actividad inhibitoria del AP7121 sobre la adherencia de Staphylococcus aureus en catéteres vasculares. Se utilizó la cepa productora de biofilm S. aureus ATCC 35556 (SA). Se estimó CIMAP7121 para SA, se inocularon segmentos de 20 mm de catéter vascular (n=3) con 104 UFC mL-1 de SA. Se probaron tres esquemas diferentes (A: simultáneo, B: anterior y C: después del desafío bacteriano) utilizando 1 x CIMAP7121. Se incluyeron grupos de control en cada esquema. La CIMAP7121 fue 0,48 mg/L. Con los esquemas A y B se logró una reducción de 2 logaritmos que representa una disminución del 99 % de células viables. El tratamiento posterior a la exposición con AP7121 (esquema C) produjo una reducción de 1 logaritmo que representa una disminución del 90 % de células viables. Estos resultados sugieren una rápida actividad antimicrobiana de AP7121 que podría ser beneficiosa para reducir la adherencia bacteriana en catéteres vasculares