Induced magnetic moment for a spinless charged particle in the thin-layer approach

We determine the effective dynamics for a spinless charged particle, in the presence of electromagnetic fields, constrained to a space curve. We employ the thin-layer procedure and a perturbative expansion for the Schr\"odinger equation is derived. We find that the first-order term in the perturbative expansion couples the dynamics of the normal and tangent degrees of freedom. However, there is always a gauge transformation that allows decouple the dynamics. We find that the effective Schr\"odinger equation in the curve contains an induced Zeeman coupling, independent of the curvature and torsion, which has not been previously reported. This coupling is characteristic of reducing the dimension by two and allows to identify an induced magnetic moment.Comment: 7 pages. To be published in Europhysics Letter

Journeys & Notes: Designing Social Computing for Non-Places

In this work we present a mobile application we designed and engineered to enable people to log their travels near and far, leave notes behind, and build a community around spaces in between destinations. Our design explores new ground for location-based social computing systems, identifying opportunities where these systems can foster the growth of on-line communities rooted at non-places. In our work we develop, explore, and evaluate several innovative features designed around four usage scenarios: daily commuting, long-distance traveling, quantified traveling, and journaling. We present the results of two small-scale user studies, and one large-scale, world-wide deployment, synthesizing the results as potential opportunities and lessons learned in designing social computing for non-places.Comment: CHI '16 Proceedings of the 2016 CHI Conference on Human Factors in Computing System

Drape optimization in woven composites manufacture.

This paper addresses the optimisation of forming in manufacturing of composites. A simplified finite element model of draping is developed and implemented. The model incorporates the non-linear shear response of textiles and wrinkling due to buckling of tows. The model is validated against experimental results and it is concluded that it reproduces successfully the most important features of the process. The simple character of the model results in low computational times that allow its use within an optimisation procedure. A genetic algorithm is used to solve the optimisation problem of minimising the wrinkling in the formed component by selecting a suitable holding force distribution. The effect of regularisation is investigated and the L-curve is used to select a regularisation parameter value. Optimised designs resulting from the inversion procedure have significantly lower wrinkling than uniform holding force profiles, while regularisation allows force gradients to be kept relatively low so that suggested process designs are feasible

Estado y desarrollo

En este trabajo recoge tres opiniones sobre el estado: la de Rostow, quien lo mira con ojos de historiador del crecimiento económico y allí, en la historia, advierte su indispensable contribución; la de Friedman y Hayek, quienes pugnan por el estado mínimo, el único que no resta al individuo “libertad para elegir”, y finalmente, la de Giddens, Przeworsky y Castells, firmes creyentes en un estado reconstruido. Se incluye la reproducción en blanco y negro de obra del artista plástico Carlos Vargas Pons.ITESO, A.C

La resurrección de las ideologías. Una reflexión a partir del 2 de julio

El 2 de julio de 2006 no fue solo una elección entre Felipe Calderón Hinojosa y Andrés Manuel López Obrador, entre el PAN y El PRD. Fue un plebiscito que confrontó de nuevo a la derecha y a la izquierda, indica el autor.ITESO, A.C