Dynamics of Dry Friction: A Numerical Investigation

We perform extended numerical simulation of the dynamics of dry friction, based on a model derived from the phenomenological description proposed by T. Baumberger et al.. In the case of small deviation from the steady sliding motion, the model is shown to be equivalent to the state- and rate-dependent friction law which was first introduced by Rice and Ruina on the basis of experiments on rocks. We obtain the dynamical phase diagram that agrees well with the experimental results on the paper-on-paper systems. In particular, the bifurcation between stick-slip and steady sliding are shown to change from a direct (supercritical) Hopf type to an inverted (subcritical) one as the driving velocity increases, in agreement with the experiments.Comment: 7 pages, 5 figures, using RevTe

Boron-oxygen defect imaging in p-type Czochralski silicon

In this work, we demonstrate an accurate method for determining the effective boron-oxygen (BO) related defect density on Czochralski-grown silicon wafers using photoluminescence imaging. Furthermore, by combining a recently developed dopant density imaging technique and microscopic Fourier transform infrared spectroscopy measurements of the local interstitial oxygen concentration [Oi ], the BO-related defect density, [Oi ], and the boron dopant density from the same wafer were determined, all with a spatial resolution of 160 μm. The results clearly confirm the established dependencies of the BO-related defect density on [Oi ] and the boron dopant density and demonstrate a powerful technique for studying this important defect.This work was supported by the Australian Research Council (ARC) Future Fellowships program and the Australian Renewable Energy Agency (ARENA) fellowships program

Beyond accessible mobility: Insights into psychosocial inclusivity dimensions in personal transport

The authors and IOS Press. © 2016 The authors and IOS Press.The importance of psychosocial aspects has been gradually recognised in the field of inclusive design. A critical review of existing literature, however, such as design, healthcare, psychology, and sociology, on psychosocial aspects of inclusivity identifies a two-fold research gap which is a limited understanding of both definition and dimensions of psychosocial inclusivity in the field of inclusive design. Such concept of psychosocial inclusivity is an inherently context-dependent and multi-faceted concept. Accordingly, a 'personal mobility' was focused on in this paper as one key context to explore psychosocial inclusivity to facilitate thorough and in-depth study of this concept. In this study, therefore, the interviews with 37 mobility-challenged participants were performed, and then the interview data was analysed by using a coding analyses to identify key psychosocial factors of inclusive design based on participants' lived-experiences

Mentality Shift in Inclusive Design: From Physical to Psychosocial Inclusion.

With the dual demographics of people with disabilities and an aging population, inclusive design has been recognised as a design application for designing products, environments and services. Also psychosocial aspects have been used for increasing quality of life in many fields of studies. However, it is not thoroughly and fully applied yet in the field of inclusive design. It is because, the physical aspects have been mainly focused rather than psychosocial aspects in the existing conventional inclusive design principles and applications. With this limited information of the concept of psychosocial aspects in the field of inclusive design, an initial definitions and frameworks for psychosocial inclusion were identified from literature analysis in this research. This initial definition and framework were then developed through an interview study. Hence, the developed definition and framework for psychosocial inclusion in the field of inclusive design were suggested. Theses definition and framework will be refined and verified through a number of research studies such as field study and Delphi interview study in later stages. The final definition and framework may play a potentially crucial role in the future of inclusive design

Cyclic cosmology from Lagrange-multiplier modified gravity

We investigate cyclic and singularity-free evolutions in a universe governed by Lagrange-multiplier modified gravity, either in scalar-field cosmology, as well as in $f(R)$ one. In the scalar case, cyclicity can be induced by a suitably reconstructed simple potential, and the matter content of the universe can be successfully incorporated. In the case of $f(R)$-gravity, cyclicity can be induced by a suitable reconstructed second function $f_2(R)$ of a very simple form, however the matter evolution cannot be analytically handled. Furthermore, we study the evolution of cosmological perturbations for the two scenarios. For the scalar case the system possesses no wavelike modes due to a dust-like sound speed, while for the $f(R)$ case there exist an oscillation mode of perturbations which indicates a dynamical degree of freedom. Both scenarios allow for stable parameter spaces of cosmological perturbations through the bouncing point.Comment: 8 pages, 3 figures, references added, accepted for publicatio

Effects Of Post-Deposition Annealing Temperature And Time On Physical Properties Of Metal-Organic Decomposed Lanthanum Cerium Oxide Thin Film.

Lanthanum cerium oxide (LaxCeyOz) precursor was prepared using metal-organic decomposition method. The effects of post-deposition annealing temperatures (400-1000 °C) and annealing time (15-120 minutes) in argon ambient on physical properties of the deposited film were investigated