XFEM coupling techniques for landslide-fluid interaction

Scientific Conference (2011)

Selected topographies on earth are threatened by sudden landslides on natural or artificial hillsides. Dur- ing landslides natural granular materials exhibit phase transitions from solid-like to fluid ... [more ▼]

Selected topographies on earth are threatened by sudden landslides on natural or artificial hillsides. Dur- ing landslides natural granular materials exhibit phase transitions from solid-like to fluid-like behavior [1]. In order to describe such materials interacting with surrounding fluids a material formulation allow- ing a switch from solid- to fluid-like state is developed. The solid-like state of the granular is modeled as compressible elastic material in an eulerian framework, while the surrounding fluid is described by an incompressible newtonian fluid. Discretization of the balance equations is carried out with a stabilized space-time finite element method [2]. The domain of elastic material utilizes mixed-hybrid space-time elements while for the surrounding fluid standard velocity-pressure elements [3] are used. Interaction of both continua is described with an interface-coupled formulation where the level-set technique [4] is employed for the interface motion. The challenge of the introduced model is the coupling of fields with discontinuous state variables as well as fieldwise different state variables. Available coupling techniques in the context of the extended finite element method and based on localized mixed hybrid formulations [5] will be discussed and evaluated numerically by means of selected 2D examples. [less ▲]

XFEM with global enrichment for 3D cracks

Scientific Conference (2015, June 17)

We present an extended finite element method (XFEM) based on fixed area enrichment which 1) suppresses the difficulties associated with ill-conditioning, even for "large" enrichment radii; 2) requires 50 ... [more ▼]

We present an extended finite element method (XFEM) based on fixed area enrichment which 1) suppresses the difficulties associated with ill-conditioning, even for "large" enrichment radii; 2) requires 50 times fewer enriched degrees of freedom (for a typical mesh) as the standard XFEM with geometrical enrichment (for the same or better accuracy level); 3) increases the accuracy level of the stress intensity factors and leads to "smooth" stress intensity variations along the crack front. [less ▲]

An XML Format Secure protocol-OpenSST

in The 3rd ACS/IEEE International Conference on Computer Systems and Applications (2005)

OpenSST (Open Simple Secure Transaction) is a free software project and aims to create an efficient, open and secure alternative to the secure proprietary transaction protocol. OpenSST uses XML syntax to ... [more ▼]

OpenSST (Open Simple Secure Transaction) is a free software project and aims to create an efficient, open and secure alternative to the secure proprietary transaction protocol. OpenSST uses XML syntax to specify its message format, and relies on prevalent cryptographic algorithms to secure the transaction. OpenSST is designed to provide user with the guarantee on confidentiality, integrity, authenticity and non-repudiation. One feature of OpenSST's is that it defines a simple message structure so that it can easily be integrated into different usage frameworks. This paper mainly describes OpenSST's logic architecture and message format through an http-based prototype. [less ▲]

XXIX workshop on geometric methods in physics, Bia\lowie\Dza Poland, June 27 -- July 3, 2010. Selected papers based on the presentations at the workshop.

Book published by AIP Conference Proceedings 1307. Melville, NY: American Institute of Physics (AIP). ix, 220~p. EUR~129.95/net; SFR~151.00; \sterling~95.00 \$~142.00 (2010)

The articles of this volume will be reviewed individually.

XXVIII Workshop on Geometrical Methods in Physics, Bialowieza, Poland, 28 June - 4 July 2009

Book published by AIP (2009)

Yactul: An Extensible Game-Based Student Response Framework for Active Learning

in Ponencias del XVIII Encuentro Internacional Virtual Educa, Colombia 2017 (2017)

Student response systems as an active learning strategy have shown to be useful in different study domains. With the advent of gamification, these environments have become very popular to improve student ... [more ▼]

Student response systems as an active learning strategy have shown to be useful in different study domains. With the advent of gamification, these environments have become very popular to improve student engagement. However, existing solutions only provide a static set of activity types and limit their use to classrooms. In this paper, we present Yactul, an extensible game-based student response framework for active learning. Our ecosystem fosters continuous learning both in the collaborative setting of the classroom and the private study environment of the student. Our modular architecture enables a seamless integration of activities from a broad and extensible set. In addition, a mobile app for offline learning extends the experience outside the classroom and allows to replay quizzes anywhere and anytime, track the progress of an individual learner and suggest activities on topics that require more studying. [less ▲]

Yang-Mills fields and random holonomy along Brownian bridges

in Annals of Probability (2003), 31(2), 769-790

Yearbook of Idiographic Science 2010 Vol 3

Book published by Firera & Liuzzo Publishing (2010)

Yes I can: The Role of self-efficacy in diabetes care

in Psychology & Health (2010), 25(1), 137-376

Based on the assumptions of social cognitive theory and self-regulation theory, the present study aimed at exploring psychosocial factors in self-care of diabetes (Edgar & Skinner, 2003; Iannotti et al ... [more ▼]

Based on the assumptions of social cognitive theory and self-regulation theory, the present study aimed at exploring psychosocial factors in self-care of diabetes (Edgar & Skinner, 2003; Iannotti et al., 2006; Nouwen et al., 2009). The study sample comprised N 1⁄4 99 patients with type 1 diabetes aged between 12 and 39 years. Participants completed the diabetes self-efficacy scale, the brief illness perceptions questionnaire, the WHO-five index and the summary of diabetes self-care activities scale. Results showed that illness perceptions (i.e. perceived consequences (r1⁄4􏰆0.28), personal control (r1⁄40.24), treatment control (r1⁄40.27), compre- hension (r1⁄40.27) and emotional response (r1⁄40.27)), as well as well-being (r1⁄40.42) and perceived diabetes self-efficacy (r 1⁄4 0.55) were significantly correlated with self-care. Furthermore, stepwise regression analyses elucidated self-efficacy (􏰈1⁄40.44) to be the most powerful predictor of self-care, as illness perceptions and well-being became non significant when introducing self-efficacy. Moreover, self-efficacy completely mediated the effect of well- being on self-care (Sobel t 1⁄4 3.74, p50.01). As for clinical implications of these results, it can be suggested that a stronger emphasise should be given on fostering patients’ confidence in their ability to effectively manage their diabetes. [less ▲]

Yoko Ono und die Macht der Kunst

Presentation (2014, March 25)