Simulation of the Elastic Properties of Reinforced Kevlar-Graphene Composites

The compressive strength of unidirectional fiber composites in the form of Kevlar yarn with a thin outer layer of graphene was investigated and modeled. Such fiber structure may be fabricated by using a strong chemical bond between Kevlar yarn and graphene sheets. Chemical functionalization of graphene and Kevlar may achieved by modification of appropriate surface-bound functional (e.g., carboxylic acid) groups on their surfaces. In this report we studied elastic response to unidirectional in-plane applied load with load peaks along the diameter. The 2D linear elasticity model predicts that significant strengthening occurs when graphene outer layer radius is about 4 % of kevlar yarn radius. The polymer chains of Kevlar are linked into locally planar structure by hydrogen bonds across the chains, with transversal strength considerably weaker than longitudinal one. This suggests that introducing outer enveloping layer of graphene, linked to polymer chains by strong chemical bonds may significantly strengthen Kevlar fiber with respect to transversal deformations

Mixtec Evangelicals

MIXTEC EVANGELICALS is a comparative ethnography of four Mixtec communities in Oaxaca, detailing the process by which economic migration and religious conversion combine to change the social and cultural makeup of predominantly folk-Catholic communities. The book describes the effects on the home communities of the Mixtecs who travel to northern Mexico and the United States in search of wage labor and return having converted from their rural Catholic roots to Evangelical Protestant religions. O’Connor demonstrates the ways that neoliberal policies have forced Mixtecs to migrate and how migration provides the contexts for conversion. Converts challenge the set of customs governing their Mixtec villages by refusing to participate in the Catholic ceremonies and social gatherings that are at the center of traditional village life. Home communities have responded in a number of ways—ranging from expulsion of converts to partial acceptance and adjustments within the village

Mixtec Evangelicals

MIXTEC EVANGELICALS is a comparative ethnography of four Mixtec communities in Oaxaca, detailing the process by which economic migration and religious conversion combine to change the social and cultural makeup of predominantly folk-Catholic communities. The book describes the effects on the home communities of the Mixtecs who travel to northern Mexico and the United States in search of wage labor and return having converted from their rural Catholic roots to Evangelical Protestant religions. O’Connor demonstrates the ways that neoliberal policies have forced Mixtecs to migrate and how migration provides the contexts for conversion. Converts challenge the set of customs governing their Mixtec villages by refusing to participate in the Catholic ceremonies and social gatherings that are at the center of traditional village life. Home communities have responded in a number of ways—ranging from expulsion of converts to partial acceptance and adjustments within the village

Mixtec Evangelicals

MIXTEC EVANGELICALS is a comparative ethnography of four Mixtec communities in Oaxaca, detailing the process by which economic migration and religious conversion combine to change the social and cultural makeup of predominantly folk-Catholic communities. The book describes the effects on the home communities of the Mixtecs who travel to northern Mexico and the United States in search of wage labor and return having converted from their rural Catholic roots to Evangelical Protestant religions. O’Connor demonstrates the ways that neoliberal policies have forced Mixtecs to migrate and how migration provides the contexts for conversion. Converts challenge the set of customs governing their Mixtec villages by refusing to participate in the Catholic ceremonies and social gatherings that are at the center of traditional village life. Home communities have responded in a number of ways—ranging from expulsion of converts to partial acceptance and adjustments within the village

The Specific Heat of a Ferromagnetic Film.

We analyze the specific heat for the $O(N)$ vector model on a $d$-dimensional film geometry of thickness $L$ using ``environmentally friendly'' renormalization. We consider periodic, Dirichlet and antiperiodic boundary conditions, deriving expressions for the specific heat and an effective specific heat exponent, \alpha\ef. In the case of $d=3$, for $N=1$, by matching to the exact exponent of the two dimensional Ising model we capture the crossover for \xi_L\ra\infty between power law behaviour in the limit {L\over\xi_L}\ra\infty and logarithmic behaviour in the limit {L\over\xi_L}\ra0 for fixed $L$, where $\xi_L$ is the correlation length in the transverse dimensions.Comment: 21 pages of Plain TeX. Postscript figures available upon request from [email protected]

Improving Spatial Codification in Semantic Segmentation

This paper explores novel approaches for improving the spatial codification for the pooling of local descriptors to solve the semantic segmentation problem. We propose to partition the image into three regions for each object to be described: Figure, Border and Ground. This partition aims at minimizing the influence of the image context on the object description and vice versa by introducing an intermediate zone around the object contour. Furthermore, we also propose a richer visual descriptor of the object by applying a Spatial Pyramid over the Figure region. Two novel Spatial Pyramid configurations are explored: Cartesian-based and crown-based Spatial Pyramids. We test these approaches with state-of-the-art techniques and show that they improve the Figure-Ground based pooling in the Pascal VOC 2011 and 2012 semantic segmentation challenges.Comment: Paper accepted at the IEEE International Conference on Image Processing, ICIP 2015. Quebec City, 27-30 September. Project page: https://imatge.upc.edu/web/publications/improving-spatial-codification-semantic-segmentatio

Simple vs complex temporal recurrences for video saliency prediction

This paper investigates modifying an existing neural network architecture for static saliency prediction using two types of recurrences that integrate information from the temporal domain. The first modification is the addition of a ConvLSTM within the architecture, while the second is a conceptually simple exponential moving average of an internal convolutional state. We use weights pre-trained on the SALICON dataset and fine-tune our model on DHF1K. Our results show that both modifications achieve state-of-the-art results and produce similar saliency maps. Source code is available at https://git.io/fjPiB