One image, two stories: Ethnographic and touristic photography and the practice of craft in Mexico

Although tourists and ethnographers take photos with different intentions and for different uses, the images they produce may be essentially similar. I explore this matter in reference to a photograph I took during research in Oaxaca, Mexico, one that is also commonly taken by tourists who visit the woodcarving workshops there. While this photo is persuasive within touristic discourses that frame Oaxaca as reflecting authentic indigenous culture, the story it tells within my ethnography is more complicated. In discussing the space between these stories, I suggest that photographs of craft practices may in turn reconstitute artisans’ practices themselves

Prediction of jet engine parameters for control design using genetic programming

The simulation of a jet engine behavior is widely used in many different aspects of the engine development and maintenance. Achieving high quality jet engine control systems requires the iterative use of these simulations to virtually test the performance of the engine avoiding any possible damage on the real engine. Jet engine simulations involve the use of mathematical models which are complex and may not always be available. This paper introduces an approach based on Genetic Programming (GP) to model different parameters of a small engine for control design such as the Exhaust Gas Temperature (EGT). The GP approach has no knowledge of the characteristics of the engine. Instead, the model is found by the evolution of models based on past measurements of parameters such as the pump voltage. Once the model is obtained, it is used to predict the behaviour of the jet engine one step ahead. The proposed approach is successfully applied for the simulation of a Behotec j66 jet engine and the results are presented

How threats influence the evolutionary resolution of within-group conflict.

© University of Chicago Press. This is the final published version of the article, deposited in accordance with SHERPA RoMEO guidelines. Also available from: http://www.jstor.org/stable/10.1086/598489Most examples of cooperation in nature share a common feature: individuals can interact to produce a productivity benefit or fitness surplus, but there is conflict over how these gains are shared. A central question is how threats to exercise outside options influence the resolution of conflict within such cooperative associations. Here we show how a simple principle from economic bargaining theory, the outside option principle, can help to solve this problem in biological systems. According to this principle, outside options will affect the resolution of conflict only when the payoff of taking up these options exceeds the payoffs individuals can obtain from bargaining or negotiating within the group; otherwise, threats to exercise outside options are not credible and are therefore irrelevant. We show that previous attempts to incorporate outside options in synthetic models of reproductive conflict fail to distinguish between credible and incredible threats, and then we use the outside option principle to develop credible synthetic models in two contexts: reproductive skew and biparental care. A striking prediction of our analysis is that outside options are least relevant to the resolution of conflict in cooperative groups of kin and are most relevant in transient associations or interactions among nonrelatives. Our analysis shows a way to link the resolution of within-group conflict to the environmental setting in which it occurs, and it illuminates the role of threats in the evolution of social behavior

Object Ensemble Processing in Human Anterior-Medial Ventral Visual Cortex

Our visual system can extract summary statistics from large collections of similar objects without forming detailed representations of the individual objects in the ensemble. Such object ensemble representation is adaptive and allows us to overcome the capacity limitation associated with representing specific objects. Surprisingly, little is known about the neural mechanisms supporting such object ensemble representation. Here we showed human observers identical photographs of the same object ensemble, different photographs depicting the same ensemble, or different photographs depicting different ensembles. We observed fMRI adaptation in anterior-medial ventral visual cortex whenever object ensemble statistics repeated, even when local image features differed across photographs. Interestingly, such object ensemble processing is closely related to texture and scene processing in the brain. In contrast, the lateral occipital area, a region involved in object–shape processing, showed adaptation only when identical photographs were repeated. These results provide the first step toward understanding the neural underpinnings of real-world object ensemble representation.Psycholog

Distributed computational fluid dynamics

Computational fluid dynamics simulations of relevance to jet-engine design, for instance, are extremely computationally demanding and the use of large-scale distributed computing will allow the solution of problems that cannot be tackled using current resources. It is often appropriate to leave the large datasets generated by CFD codes local to the compute resource in use at the time. This naturally leads to a distributed database of results that will need to be federated as a coherent resource for the engineering community. We describe the use of Globus and Condor within Cambridge for sharing computer resources, progress on defining XML standards for the annotation of CFD datasets and a distributed database framework for them

Ana's Friends. Friendship in Online Pro-Ana Communities

The objective of this article is to analyse the social relationships within online communities of anorectics, their bonds, their emotions and friendships, and their subsequent relation to anorexia nervosa. The research has focused on their blogs and their forums, which create a space in which they share their experiences, and sometimes encourage each other not to give up on their eating disorder – which they view as an illness, but an illness that has become their lifestyle, and their attitude towards life. Within the article an analysis of the special bonds of friendship that tie the members of the online community together will be presented. Special attention will be paid to the similarities between secret societies and friendship bonds within pro-ana communities.Friendship, Secret, Emotions, Internet, Anorexia, Pro-Anorexia

Creating AI characters for fighting games using genetic programming

This paper proposes a character generation approach for the M.U.G.E.N. fighting game that can create engaging AI characters using a computationally cheap process without the intervention of the expert developer. The approach uses a Genetic Programming algorithm that refines randomly generated character strategies into better ones using tournament selection. The generated AI characters were tested by twenty-seven human players and were rated according to results, perceived difficulty and how engaging the gameplay was. The main advantages of this procedure are that no prior knowledge of how to code the strategies of the AI character is needed and there is no need to interact with the internal code of the game. In addition, the procedure is capable of creating a wide diversity of players with different strategic skills, which could be potentially used as a starting point to a further adaptive process