Optimization of Patterned Surfaces for Improved Superhydrophobicity Through Cost-Effective Large-Scale Computations

The growing need for creating surfaces with specific wetting properties, such as superhyrdophobic behavior, asks for novel methods for their efficient design. In this work, a fast computational method for the evaluation of patterned superhyrdophobic surfaces is introduced. The hydrophobicity of a surface is quantified in energy terms through an objective function. The increased computational cost led to the parallelization of the method with the Message Passing Interface (MPI) communication protocol that enables calculations on distributed memory systems allowing for parametric investigations at acceptable time frames. The method is demonstrated for a surface consisting of an array of pillars with inverted conical (frustum) geometry. The parallel speedup achieved allows for low cost parametric investigations on the effect of the fine features (curvature and slopes) of the pillars on the superhydophobicity of the surface and consequently for the optimization of superhyrdophobic surfaces.Comment: 18 pages, 18 figure

Isokinetic Evaluation of the Elbow Joint at 45° and 80° of Shoulder Abduction

Since Hislop and Thistle published the first reports on isokinetic exercise, a lot of progress has been made towards the use of isokinetic exercise and isokinetic evaluation of muscle and joint performance in sports and orthopedic physical therapy. Cybex II+ with the Cybex Data Reduction Computer is one of the most widely used isokinetic systems for research and rehabilitation purposes. There are more than 500 published works describing the use of Cybex in various applications, Many investigations have used the Cybex isokinetic system to develop normative data on torque and work measurements of various muscle groups. Normative data are valuable to clinicians in the evaluation of the severity of an injury in terms of muscle performance deficits. In addition, such data provide physical therapists with objective data in setting rehabilitation goals, and enabling sports medicine experts to identify functional deficiencies during screening of athletes. There is a limited number of published works that have developed normative data for elbow flexor and extensor muscle groups. While there is some information about peak torque and agonist-antagonist ratios, minimal information is available about torque acceleration energy, work endurance ratios, average power and flexion-extension total work ratios. The purpose of this study was to examine the effects of 450 and 800 of shoulder abduction on torque and work measurements of the elbow joint. In addition, normative data for elbow flexion and extension at both arm positions (testing positions suggested by Cybex) were developed

The normal field instability under side-wall effects: comparison of experiments and computations

We consider a single spike of ferrofluid, arising in a small cylindrical container, when a vertically oriented magnetic field is applied. The height of the spike as well as the surface topography is measured experimentally by two different technologies and calculated numerically using the finite element method. As a consequence of the finite size of the container, the numerics uncovers an imperfect bifurcation to a single spike solution, which is forward. This is in contrast to the standard transcritical bifurcation to hexagons, common for rotational symmetric systems with broken up-down symmetry. The numerical findings are corroborated in the experiments. The small hysteresis observed is explained in terms of a hysteretic wetting of the side wall.Comment: accepted to New Journal of Physic

Χρήση του δείκτη QBR για την εκτίμηση των επιπτώσεων της κατασκευής φραγμάτων κατά μήκος της κοίτης ενός μεσογειακού χειμάρρου στην παρόχθια βλάστηση

Ο χείμαρρος «Γεραμπίνη» Ζαγοράς Πηλίου, ο οποίος αποτελεί την περιοχή μελέτης, είναι ένα υδατικό οικοσύστημα με έντονες διακυμάνσεις στο υδρολογικό του ισοζύγιο. Με κύριο στόχο την αποτροπή των πλημυρρικών φαινομένων, κατασκευάστηκαν κατά μήκος του, είκοσι ένα (21) φράγματα στερέωσης. Στην παρούσα εργασία προσδιορίζεται και αναλύεται ο δείκτης QBR «Qualitat del Bosc de Ribera», ο οποίος αποτελεί έναν αξιόπιστο ποιοτικό δείκτη της παρόχθιας βλάστησης για τα μεσογειακά υδατικά οικοσυστήματα. Από την συλλογή, επεξεργασία και ανάλυση των δεδομένων προκύπτει ότι η τεχνητή διευθέτηση του μεσογειακού χειμάρρου δεν αποτέλεσε τροχοπέδη στη διατήρηση και στην αναβάθμιση της δυναμικής των στοιχείων που συντελούν στη φυσική εξέλιξη της παρόχθιας βλάστησής του

IMPROVING THE RESOLUTION OF SEISMIC HAZARD ESTIMATES FOR CRITICAL FACILITIES: THE DATABASE OF GREEK CRUSTAL SEISMOGENIC SOURCES IN THE FRAME OF THE SHARE PROJECT

SHARE (Seismic Hazard Harmonization in Europe) European project aims at delivering measurable progress in all steps leading to a harmonized assessment of seismic hazard in Europe -in the definition of engineering requirements, in the collection and analysis of input data, in procedures for hazard assessment, and in engineering applications. In this frame, a database of the shallow (crustal) seismogenic sources for the broader Aegean Region is developed The Greek database focuses on three major goals: (i) the systematic collection of all available information concerning neotectonic, active and capable faults as well as broader seismogenic volumes; (ii) the critical analysis of the data and the quantification of the principal seismotectonic parameters of the various sources and the associated degree of uncertainty; (iii) to supply an integrated view of potentially damaging seismogenic sources for a better SHA in Greece. The informatic framework of the database follows that used for the Italian DISS. In this paper we present the state-of-the-art of the Composite Seismogenic Sources (CSS) for the broader Aegean region. The Aegean Region is among the most tectonically active areas of the Mediterranean realm and has the highest seismicity both in terms of frequency of events and magnitudes. The tectonic regime is rather complex producing earthquakes with many different orientations of nodal planes and a large variety of fault types both in terms of dimension and kinematics. It is not always straightforward to correlate seismicity with the causative fault(s). This is mainly due to two reasons: firstly, several crustal sectors of the Aegean, where historical or instrumental epicentres are located, are affected by a dense fault population bearing evidences of recent activity but with badly defined seismotectonic behaviour. Secondly, large sectors of the broader Aegean Region are covered by the sea, therefore lacking crucial field and direct observations. In the latter case, the typical geological approaches are generally replaced with geophysical and seismological investigations (detailed bathymetry, seismic profiles, microseismicity, focal mechanisms, etc.), which can be proved very useful. A first attempt to create a similar database for the Greek territory was carried out during the EU project FAUST (2001), where ca. 50 earthquake-related sources have been included. In contrast, the most recent and the most complete map of capable faults in Greece and the broader Aegean Region has been compiled by Other attempts have been performed in the past, but all of them were lacking in both fault and data completeness. For example, simple map compilations cannot provide much information except the geographical location and few geometrical characteristics of the faults, like length and dip direction. On the other hand, fault catalogues generally lack important additional data, like geometric, kinematic and seismological ones. In order to bypass the above problems and to make the database a continuously updatable open-file, the choice of a GIS-based software was crucial. For our purpos-232 GNGTS 2011 SESSIONE 2.

Game Based Learning on Urban Sustainability: The "Sustain" Project

SUSTAIN is an ERASMUS+ project with an innovative perspective on urban sustainability. Its target is to promote the importance of sustainability on the everyday problems of the cities among the students of higher education, which are the policy makers of tomorrow and the ones that will shape the future. In order to achieve its goals, the research team will develop a course that will be based on an interactive game with an analytical style of education. This game will allow students to learn about transportation sustainability and societal metabolism through playing. In addition, the research team will develop small and illustrative simulation models, which will make the definitions more concrete and allow students to experiment in a consequence-free environment. It is a quite innovative and hybrid perspective way of learning, in the sense that it will combine game-based learning with a cognitive and analytical style of education

Probing the Space of Toric Quiver Theories

We demonstrate a practical and efficient method for generating toric Calabi-Yau quiver theories, applicable to both D3 and M2 brane world-volume physics. A new analytic method is presented at low order parametres and an algorithm for the general case is developed which has polynomial complexity in the number of edges in the quiver. Using this algorithm, carefully implemented, we classify the quiver diagram and assign possible superpotentials for various small values of the number of edges and nodes. We examine some preliminary statistics on this space of toric quiver theories