Evidence of slippage breakdown for a superhydrophobic microchannel

© 2014 AIP Publishing LLC.A full characterization of the water flow past a silicon superhydrophobic surface with longitudinal micro-grooves enclosed in a microfluidic device is presented. Fluorescence microscopy images of the flow seeded with fluorescent passive tracers were digitally processed to measure both the velocity field and the position and shape of the liquid-air interfaces at the superhydrophobic surface. The simultaneous access to the meniscus and velocity profiles allows us to put under a strict test the no-shear boundary condition at the liquid-air interface. Surprisingly, our measurements show that air pockets in the surface cavities can sustain non-zero interfacial shear stresses, thereby hampering the friction reduction capabilities of the surface. The effects of the meniscus position and shape as well as of the liquid-air interfacial friction on the surface performances are separately assessed and quantified

Virtual reconstruction from scan to VR of architecture and landscape of a monumental park

The Monza Park, with its more than 7 square meters of green area divided between lawn and woods, its 110,000 tall trees, its 13 farmhouses, 3 historic villas, 13 m of fences and 90,000 visitors on spring Sundays, represents an irreplaceable source of wellness and sustainability for those who live near it. The pandemic situation of the 20s and 21s by reducing the movements and the possibility of coexistence of a large public in an open space has suggested the possibility of new forms of use and interaction of the same, even remotely, reproducing Virtual and Augmented Reality experiences. With this paper, the authors intend to illustrate a workflow from Scan to VR and AR applications, taking advantage of the opportunity to explore digital acquisitions and additional materials available and functional to convey the values and importance of open space and historical monuments immersed in them. The VR/AR experiences have been structured for navigation from the scale of architectural detail to the environmental one, which effectively ensures the fruition of one of the most significant and large historical walled parks in Europe. An unprecedented and still unique park made up of woods, meadows, cultivated fields, the Lambro, the farmhouses and villas, the mills inserted in an apparently natural but carefully designed environment

Optimization of VR application in texturing cultural heritage

The research question underlying this short essay refers to the possibility of realizing through a well-established workflow a high level of immersivity in the VR representation of Cultural Heritage to be used as a working tool by architects and renovators as well as heritage scholars. At present active or passive 3D scanning techniques are a known reality where the choice of data acquisition system depends both on the final purpose and characteristics of the object to be surveyed. With the maturity achieved in point cloud acquisition, post processing phases and the development of BIM-based systems, the model has given the possibility to become a repository of information related to the existing, to be used for maintenance or renovation processes. If the model can represent the existing with a certain level of detail, it can be assumed that a differentiated Level of Immersivity can be organized depending on the specific needs it intends to fulfil. In the context of renovation or preservation of Cultural Heritage, the potential offered by VR becomes more interesting when it can provide a realistic portrait not only of the geometry, but also of the materiality and state of preservation of the buildings. This research opens new possibilities to develop tools to aid designers and renovators in degradation analysis, intervention projects, and scheduled maintenance. The research question starts analyzing the possibility of creating photorealistic immersive environments that are easy to access, organized based on surveys of existing heritage buildings using specific datasets

Point cloud management for a holographic visualization

This document aims to describe and verify the workflow from a digital survey of a building of historical value to its set up in an innovative holographic view. Via Lulli is a low-cost building of the beginning of the century organized in a closed-block part of a complex with rather small courtyards; the research topic concerns the verification of the process from acquisition with digital survey to convert the survey dataset into a hologram, considering the huge potential of this display system. Comparison among different point clouds, with different accuracy and dimension are related to the final navigation when transformed in holograms; several tests have been carried out to compare cloud density with the ability to see holograms in details with different zooms in to display small details, and zooms out in real time to view the entire model. First possibility to extend workflow with unity support and other plug-ins are supposed

CULTURAL HERITAGE DISSEMINATION: BIM MODELLING AND AR APPLICATION FOR A DIACHRONIC TALE

The research purpose is to present a project of cultural dissemination and enhancement of the “Madonna della Pace” Sanctuary at Rocchetta di Airuno (Lecco - Italy), based on an immersive experience of knowledge of the history and places that characterize not only the sanctuary but also the “Cammino di Sant’Agostino” (of which it is one of the stages). The research goal focuses on the direct employment and exploitation of HBIM models for the digital fruition project. An integrated digital survey based on a terrestrial laser scanner and photogrammetry was conducted to provide a complete geometrical representation of the sanctuary and its surroundings. Both output point clouds were employed as metric and geometric references to create the reality-based parametric model. Specifically, the work focuses on creating a three-dimensional chronological model of the sanctuary, which not only represents the current state of the cultural asset but is also enriched through the definition of different evolutionary phases of the architectural artifact based on an indepth study of the photographic and bibliographic documentations. Four Project Phasing has been identified to represent the most significant transformations of the building and were managed using the time parameter in the same BIM project. The sanctuary geometric and parametric models were displayed and navigable thanks to the aid of Virtual and Augmented Reality applications. A VR environment was defined to display in the first person the textured model. Finally, an AR smartphone app prototype was developed to show tourists the sanctuary’s historical transformation over time

On the Possibility of a Trans-Planckian Duality

We investigate the possibility of a trans-Planckian duality, which exchanges a manifold of events (space-time), with a manifold of momenta (energy-momentum). Gravity has a dual counter-part, that is, a geometric theory defined on the manifold of momenta. We provide a mathematical framework that can possibly realize this idea, and analyze its classical behaviour.Comment: 21 pages, 4 figure

DNA damage induced by 7,12-dimethylbenz[a]anthracene in the liver and the mammary gland of rats exposed to polycyclic aromatic hydrocarbon enzyme inducers during perinatal life

The long-lasting modulating effect induced by the prenatal or neonatal exposure to phenobarbital (PB) and aroclor on the genotoxic activity of 7,12-dimethylbenz[a]anthracene (DMBA) in female Sprague-Dawley rats was studied. The effect was measured as DNA damage evaluated in the liver and in the mammary gland of 55-day-old animals, 4 and 24 h after an i.g. injection of 80 mg/kg of DMBA. PB was given per os, i.g. or in drinking water to pregnant females and by i.g. only to neonates or in adult progeny. Aroclor was injected i.g. in prenatal and in neonatal life, and a second dose was given in adult life. Under these experimental conditions it was shown that DNA damage kinetics caused by DMBA are modulated by exposure to PB and, to a minor extent, by aroclor. The amount and persistence of DNA damage were highest when PB was administered to neonates. An average 2-fold increase in the elution constants (K) of DNA in the liver and the mammary gland was observed 4 h after DMBA treatment, as compared to uninduced animals. Repeated enzyme induction by PB seems to reduce DMBA genotoxicity, as shown by a decrease in DNA damage and persistence in the liver and mammary gland. The inducibility of the monooxygenase enzyme system in perinatal life favouring metabolic activation of inactivation of polycyclic aromatic hydrocarbons might be critical in determining individual susceptibility of adult progeny to chemical carcinogenesis by DMB

Strings Inside Walls in N=1 Super Yang-Mills

We conjecture the existence of strings bounded inside walls in SU$(n)$ $\N=1$ Super Yang-Mills theory. These strings carry $\Z_{[k,n]}$ quantum number, where $[k,n]$ is the greatest common divisor between $k$, the charge of the wall, and $n$. We provide field-theoretical arguments and string-theoretical evidences, both from MQCD and from gauge-gravity correspondence. We interpret this result from the point of view of the low-energy effective action living on the $k$-wall.Comment: 25 pp. Major changes. In particular, following the recent work arXiv:0807.1908 we have been able to give a field theoretical proof of the statement. We have also corrected an important erroneous interpretation in the previous version regarding the 2+1 effective action; Typo

Holographic visions for architecture in a park.

The Monza Park, with its more than 7 square meters of green area, divided between lawn and woods, its 110,000 tall trees, its 13 farmhouses, 3 historic villas, 13 m of fences and 90,000 visitors on spring Sundays, represents an irreplaceable source of wellness and sustainability for those who live near it. The pandemic situation of the 20s and 21s by reducing the movements and the possibility of coexistence of a large public in an open space has suggested the possibility of new forms of use and interaction of the same, even remotely, reproducing accurate Virtual Reality experiences. With this paper, the authors intend to illustrate a workflow from Scan to VR applications, taking advantage of the opportunity to explore digital acquisitions and additional materials available and functional to convey the values of open space and historical monuments immersed in them. The VR experiences have been structured for the navigation from the scale of architectural detail to the environmental one, with the goal of using the accurate model results for two different and remote instrumentations: a 7m diameter 360° theatre and a Holographic table, Euclideon Hologram Table©. Both situations, as opposed to hardware tools such as headset, favour the fruition for small groups of users

Compositional Performance Modelling with the TIPPtool

Stochastic process algebras have been proposed as compositional specification formalisms for performance models. In this paper, we describe a tool which aims at realising all beneficial aspects of compositional performance modelling, the TIPPtool. It incorporates methods for compositional specification as well as solution, based on state-of-the-art techniques, and wrapped in a user-friendly graphical front end. Apart from highlighting the general benefits of the tool, we also discuss some lessons learned during development and application of the TIPPtool. A non-trivial model of a real life communication system serves as a case study to illustrate benefits and limitations