Comment on: Thermostatistics of Overdamped Motion of Interacting Particles [arXiv:1008.1421]

In a recent paper, Phys. Rev. Lett. 105 260601 (2010) [arXiv:1008.1421], Andrade et al., argued that classical particles confined in a parabolic trap at T=0 distribute themselves in accordance with the Tsallis statistics. To prove their point the authors performed molecular dynamics simulations. Here we show that the model of Andrade et al. can be solved exactly. The distribution of particles at T=0 has nothing to do with the Tsallis entropy and is determined simply by the force balance

Dislocation jamming and Andrade creep

We simulate the glide motion of an assembly of interacting dislocations under the action of an external shear stress and show that the associated plastic creep relaxation follows Andrade's law. Our results indicate that Andrade creep in plastically deforming crystals involves the correlated motion of dislocation structures near a dynamic transition separating a flowing from a jammed phase. Simulations in presence of dislocation multiplication and noise confirm the robustness of this finding and highlight the importance of metastable structure formation for the relaxation process.Comment: 4 pages, 4 EPS figure

Coordination Contracts as Connectors in Component-Based Development

Several proposals for component-based development methods have started to appear. However, the emphasis is still very much on the development of components as opposed to the development with components. The main focus is on how to generate ideal reusable components not on how to plug existing components and specify their interactions and connections. The concept of a coordination contract (Andrade and Fiadeiro 1999; Andrade and Fiadeiro 2001; Andrade, Fiadeiro et al. 2001) has been proposed to specify a mechanism of interaction between objects based on the separation between structure, what is stable, and interaction, what is changeable. This separation supports better any change of requirements, as contracts can be replaced, added or removed dynamically, i.e. in run-time, without having to interfere with the components that they coordinate. A coordination contract corresponds to an expressive architectural connector that can be used to plug existing components. In this paper we integrate the concept of a coordination contract with component-based development and show how coordination contracts can be used to specify the connectors between components

Universities as Living Labs for sustainable development : a global perspective

Walter Leal Filho, Baltazar Andrade Guerra, Mark Mifsud and Rudi Pretorius use case studies from Brazil, Malta and South Africa to reflect on how the Living Labs approach can contribute towards a more sustainable futurepeer-reviewe

Spatial fluctuations in transient creep deformation

We study the spatial fluctuations of transient creep deformation of materials as a function of time, both by Digital Image Correlation (DIC) measurements of paper samples and by numerical simulations of a crystal plasticity or discrete dislocation dynamics model. This model has a jamming or yielding phase transition, around which power-law or Andrade creep is found. During primary creep, the relative strength of the strain rate fluctuations increases with time in both cases - the spatially averaged creep rate obeys the Andrade law $\epsilon_t \sim t^{-0.7}$, while the time dependence of the spatial fluctuations of the local creep rates is given by $\Delta \epsilon_t \sim t^{-0.5}$. A similar scaling for the fluctuations is found in the logarithmic creep regime that is typically observed for lower applied stresses. We review briefly some classical theories of Andrade creep from the point of view of such spatial fluctuations. We consider these phenomenological, time-dependent creep laws in terms of a description based on a non-equilibrium phase transition separating evolving and frozen states of the system when the externally applied load is varied. Such an interpretation is discussed further by the data collapse of the local deformations in the spirit of absorbing state/depinning phase transitions, as well as deformation-deformation correlations and the width of the cumulative strain distributions. The results are also compared with the order parameter fluctuations observed close to the depinning transition of the 2$d$ Linear Interface Model or the quenched Edwards-Wilkinson equation.Comment: 27 pages, 18 figure

Andrade, Audrey B., Collection, 1862-2014

A collection of genealogical records, school records, work documents, music, photographs, and books related to Audrey Andrade and her friends and family. Audrey Beatrice Edge Andrade was born in Stockton, Missouri on January 15, 1917 to George W. and Maud Ritter Edge. Andrade grew up in Pittsburg, Kansas, attended Lakeside Elementary School, and graduated from Pittsburg High School in 1934. She received her two-year education degree from Kansas State Teachers College (now Pittsburg State University) in 1936. She married John F. Andrade who served as a staff sergeant in the US Army during World War II. They had five children. Mr. Andrade worked for product distribution companies like Milhender and sold household appliances. Mrs. Andrade had an interest in music including piano, violin, and singing. John Andrade passed away in 1978 and Audrey Andrade passed away in 1996. The couple are buried in Rhode Island Veterans Memorial Cemetery, in Exeter, Rhode Island.https://digitalcommons.pittstate.edu/fa/1299/thumbnail.jp