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Culture exploits the acquisition of meaningful content by crafting regimes of shared attention, determining what is relevant, valuable, and salient. Culture changes the field of relevant social affordances worthy of being acted upon in a context-sensitive manner. When relevant affordances are highly weighted, their attentional capture and their salience increase the probability of them being enacted due to the associated expectation for minimizing prediction error. This process is known as active inference. In the digital era, individuals need to infer the action-related attributes of digital cues, here characterized as digital affordances. The digital affordances of digital social platforms are of particular interest here. Digital social affordances are defined as online possibilities of social interactions. By their own nature, these are salient because they are related to social interactions and relevant social cues. However, the problem of digital social platforms is that they are not equivalent to situated social interactions because their structure is built, mediated, and defined by third-parties with diverse interests. The third-parties behind the digital social platforms are using the same mechanism exploited by culture to manipulate the shared patterns of attention. Moreover, digital social platforms are deliberately designed to be hyper-stimulating, making digital social affordances highly rewarding and increasingly salient. This appropriation, for economic purposes, is an issue of great importance, especially as the COVID-19 pandemic brought deep global changes, pushing societies to an online digital way of life. Here, we examined different types of digital social affordances under an active inference view, placing them into two categories, those for self-identity formation, and those for belief-updating. This paper aims to analyze digital social affordances in light of the prediction error dynamics they might elicit to their users. Although each of the analyzed digital social affordances allows different epistemic and instrumental digital actions, they all share the characteristic of having an "easy" and a fast expected rate of error reduction. Here, we aim to provide a new hypothesis about how the design behind digital social affordances is built on our natural attractiveness to minimize prediction error and the resulting positive embodied feelings when doing so. Finally, it is suggested that because digital social affordances are becoming highly weighted in the field of affordances, this might be putting at risk our context-sensitive grip on a rich, dynamic and varied field of relevant affordances.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Titanium alloys have got features that classify them as excellent candidates for medical applications. However, they have porr machinability mainly due to their low thermal conductivity, high chemical affinity to almost every tool material and their small modulus of elasticity. Regarding commercial milling tools, inserts usually differ one to another in terms of grade (such as substrate and coating composition and microstructure) and geometric characteristics (nose radius, rake angle and chipbreaker shape), so that it is difficult to find two products differentiated by one single variable. Due to these factors, the general goal of this research is to investigate the correlation between tool nose radius and the roughness after milling of Ti-6Al-4V ELI titanium alloy. For that, it was necessary to grind carbide inserts to prepare the three different nose radii (re = 0.8 mm; 1.2 mm or 1.6 mm) as well as their characterization, besides designing, manufacturing and evaluating a customized tool holder with a single insert seat. Tools once prepared were tested through face milling experiments, keeping fixed cutting speed (vc) at 60 m/min, axial depth of cut (ap) at 1 mm, in addition to radial depth of cut (ae) at 16.8 mm and flood coolant. Five diferente levels were used for feed per tooth ( fz): 0.10 mm; 0.15 mm; 0.20 mm; 0.25 mm or 0.30 mm. After the experiments, the specimens were evaluated in terms of different roughness parameters, and all data were statistically analyzed by means of analysis of variance (ANOVA). Regarding the characterization of the ground inserts, there was no significant variation in the irregularity of the edges as a function of the different nose radii. The design of the tool holder proved out to be adequate to the operation, providing a high design safety factor. Regarding the surface integrity of the machined surfaces, results show that, in exception of one tested condition, all other values of Ra satisfy N6 roughness grade. The pass associated to re = 0.8 mm and fz = 0.15 mm probably provided higher vibrations. ANOVA indicates that, in statistical terms, only feed ( f ) and the interaction between feed and nose radius ( f x re) affect the roughness parameters Ra, Rq, Rt, Rz, and Rmax, although these effects are not obvious. There was no statistically significant difference for skewness (Rsk), which tends to zero and, therefore, expresses an approximately symmetrical surface in terms of peaks and valleys. The same for kurtosis (Rku), which remained close to three, which means a distribution close to normal. Ligas de titânio possuem características que as classificam como excelentes candidatas para aplicações médicas. Porém, possuem uma usinabilidade baixa em razão, principalmente, de sua baixa condutividade térmica, elevada afinidade química com quase todos os materiais das ferramentas e de seu módulo de elasticidade reduzido. Em se tratando de ferramentas comerciais de fresamento, os insertos usualmente se diferenciam em termos de classe (como composição e microestrutura do substrato e da cobertura) e das características geométricas (raio de ponta, ângulo de saída e forma do quebra-cavaco), de maneira que é raro encontrar dois produtos diferenciados por uma única variável. Por esses fatores, o objetivo geral desta pesquisa é investigar a relação entre o raio de ponta da ferramenta e a rugosidade após o fresamento da liga de titânio Ti-6Al-4V ELI. Para isso, foi necessária a retificação de insertos de metal duro para preparar os três diferentes raios de ponta (re = 0,8 mm; 1,2 mm ou 1,6 mm), bem como sua caracterização, além de projetar, fabricar e aferir um porta-ferramentas customizado com assento para um único inserto. As ferramentas preparadas foram testadas por meio de ensaios de fresamento frontal, mantendo como constantes, a velocidade de corte (vc) em 60 m/min, a profundidade de usinagem (ap) em 1 mm, além da penetração de trabalho (ae) em 16,8 mm e refrigeração abundante. Foram empregados cinco níveis distintos para o avanço por dente ( fz): 0,10 mm; 0,15 mm; 0,20 mm; 0,25 mm ou 0,30 mm. Após os ensaios, os corpos de prova foram caracterizados em termos de diferentes parâmetros de rugosidade, sendo todos os dados analisados estatisticamente por meio da análise de variância (ANOVA). Com relação à caracterização dos insertos retificados, não se verificou variação significativa na irregularidade das arestas em função dos diferentes raios de ponta preparados. O dimensionamento do portaferramentas se mostrou adequado para a operação, conferindo um coeficiente de segurança de projeto elevado. Sobre a integridade superficial das superfícies usinadas, os resultados mostram que com exceção de uma condição testada, todos os demais valores de Ra atendem à classe de rugosidade N6. O passe envolvendo re = 0,8 mm e fz = 0,15 mm provavelmente ocasionou maiores vibrações. A ANOVA indica que, em termos estatísticos, há influência somente do avanço ( f ) e da interação entre o avanço e o raio de ponta ( f x re) sobre os parâmetros de rugosidade Ra, Rq, Rt, Rz e Rmax, embora esses efeitos não sejam óbvios. Não se verificou diferença estatisticamente significativa para o fator de assimetria (Rsk), que tende a zero e, portanto, exprime uma superfície aproximadamente simétrica em termos de picos e vales. O mesmo para o fator de achatamento (Rku), que se manteve próximo a três, o que significa uma distribuição próxima à normal. Processos n° 2015/15622-2, 2017/12309-7 e 2017/12304-5, Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Processos n° 88887.602219/2021-00, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Distance perception for mobile agents is of great importance for safe navigation in unknown environments. Traditional methods make use of analytical solutions. Yet, according to some research hypothesis, distance perception is not the result of mathematical calculations, but an emergent consequence of an association process, where visual and tactile information acquire a central role. Designing models closer to natural cognition poses paramount challenges to artificial intelligence (AI), which call for a review of some of the foundations of current methods. Our work is framed in the embodied cognition paradigm, which highlights the importance of the body for the development of cognitive processes. We provide theoretical grounds and empirical evidence for an artificial account of distance perception through a multimodal association process. By learning multimodal sensorimotor schemes, an agent is capable of perceiving affordances related to distance perception without any non-body-based geometric knowledge. We let an agent interact with an environment cluttered with objects, while learning multimodal sensorimotor associations. The learned spatial relations are thoroughly characterized to show how the model depends on the agent’s specific sensorimotor capabilities. The system is tested in a passability experiment and a navigation task, showing the agent anticipates undesired situations using the learned model predictions.

Antecedentes: La imagen corporal es la percepción que cada individuo posee de su propio cuerpo y resulta de una construcción multidimensional la cual —en ocasiones— no está correlacionada con el aspecto físico real. Objetivo: Conocer la percepción corporal de mujeres de 25 años del municipio de Ponedera (Atlántico) a través del Body Shape Questionnaire (cuestionario de la forma corporal) BSQ. Materiales y métodos: Estudio cuantitativo de tipo descriptivo y corte transversal. El ámbito de estudio que se presenta en este artículo ha sido el municipio de Ponedera (Atlántico). Participaron 145 mujeres en edad de 25 años de dos barrios populares del municipio de Ponedera (Atlántico), que respondieron a un cuestionario de autocumplimentación de forma voluntaria y anónima. BSQ. Resultados: se apreció una tendencia de la mayoría de la muestra hacia una preocupación extrema por la imagen corporal (92%), es decir, las mujeres que se ubicaron en esta categoría reconocen tener problemas asociados al exceso de peso, como también ciertos complejos a la hora de interactuar en su contexto teniendo presente que para ellas es importante lo que puedan decir las demás personas sobre su cuerpo y por ende, evitan situaciones en las que su imagen corporal sea materia de discusión. Conclusión: Es preciso que en este sector se lleven a cabo campañas para promover la actividad física al igual que secciones con expertos en nutrición que brinden pautas para la sana alimentación a fin de que la población femenina de este entorno adquiera estilos de vida saludable.

Biological agents are context-dependent systems that exhibit behavioral flexibility. The internal and external information agents process, their actions, and emotions are all grounded in the context within which they are situated. However, in the field of cognitive robotics, the concept of context is far from being clear with most studies making little to no reference to it. The aim of this paper is to provide an interpretation of the notion of context and its core elements based on different studies in natural agents, and how these core contextual elements have been modeled in cognitive robotics, to introduce a new hypothesis about the interactions between these contextual elements. Here, global context is categorized as agent-related, environmental, and task-related context. The interaction of their core elements, allows agents to first select self-relevant tasks depending on their current needs, or for learning and mastering their environment through exploration. Second, to perform a task and continuously monitor its performance. Third, to abandon a task in case its execution is not going as expected. Here, the monitoring of prediction error, the difference between sensorimotor predictions and incoming sensory information, is at the core of behavioral flexibility during situated action cycles. Additionally, monitoring prediction error dynamics and its comparison with the expected reduction rate should indicate the agent its overall performance on executing the task. Sensitivity to performance evokes emotions that function as the driving element for autonomous behavior which, at the same time, depends on the processing of the interacting core elements. Taking all these into account, an interactionist model of contexts and their core elements is proposed. The model is embodied, affective, and situated, by means of the processing of the agent-related and environmental core contextual elements. Additionally, it is grounded in the processing of the task-related context and the associated situated action cycles during task execution. Finally, the model proposed here aims to guide how artificial agents should process the core contextual elements of the agent-related and environmental context to give rise to the task-related context, allowing agents to autonomously select a task, its planning, execution, and monitoring for behavioral flexibility.