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We point out a strong time evolution of the mass-to-light conversion factor, η, commonly used to estimate masses of unresolved star clusters from observed cluster spectrophotometric measures. We present a series of gas-dynamical models, coupled with the Cambridge stellar evolution tracks, to compute line-of-sight velocity dispersions and half-light radii weighted by the luminosity. We explore a ra
The project "Silent Timber Build" will develop new prediction tools for timber structures. There are several challenges that have to be overcome to provide a full prediction tool. The differences in weight, stiffness and density for wooden structures compared to traditional, heavy and more homogeneous structural material have repercussions on how the sound propagates throughout the structures, aff
The tidal field of galaxies is known generally to be disruptive. However, in the case of galaxy mergers, a compressive mode of tidal wave may develop and last long enough to cocoon the formation of star clusters. Using an N‐body simulation of the Antennae galaxies, we derive the positions of these compressive regions and the statistics of their duration. Excellent agreement between the spatial dis
We present a novel and flexible tensor approach to computing the effect of a time-dependent tidal field acting on a stellar system. The tidal forces are recovered from the tensor by polynomial interpolation in time. The method has been implemented in a direct-summation stellar dynamics integrator (NBODY6) and test-proved through a set of reference calculations: heating, dissolution time and struct
Noise control in buildings should aim at reducing disturbances caused by speech noise (i.e., improve speech privacy, speech intelligibility). Room acoustics can be controlled with high room absorption, high screens and bookcases, and sufficient masking sound. This research concerns as important aspect of room acoustic metrology, the ability to quantify the most relevant room acoustic parameters fo
We present an analytical model of the relation between the surface density of gas and star formation rate in galaxies and clouds, as a function of the presence of supersonic turbulence and the associated structure of the interstellar medium (ISM). The model predicts a power-law relation of index 3/2, flattened under the effects of stellar feedback at high densities or in very turbulent media, and
The latest version of the Swiss standard for building acoustics (SIA181) introduced a new measurement method, based on a balanced- Arm hammer, for evaluating the decoupling performance of service equipment. This method was developed for reproducing in a standard manner the manipulation of service equipment in bathrooms and kitchens. In this study, we are investigating the relevance of such method
Long tails and streams of stars are the most noticeable traces of galaxy collisions. However, their tidal origin was recognized only less than 50 years ago and more than 10 years after their first observations. This review describes how the idea of galactic tides has emerged thanks to advances in numerical simulations, from the first simulations that included tens of particles to the most sophisti
We present smoothed particle hydrodynamic models of the interactions in the compact galaxy group, Stephan's Quintet. Adding thermohydrodynamic effects to the earlier collisionless N-body simulations of Renaud et al., we further investigate the dynamical interaction history and evolution of the intergalactic gas of Stephan's Quintet. Specifically, we reproduce the major stellar and gas features of
Soundscape management in a city implies mitigating harmful sounds and promoting useful ones, according to their environmental, social or cultural significance and considering a more human centered paradigm. The Soundscape approach does not consider sound as a waste but a resource and its application may reach more benefits than solely noise control actions. This conception conveys an emerging para
Gravitational tides are widely understood to strip and destroy galactic substructures. In the course of a galaxy merger, however, transient totally compressive tides may develop and prevent star-forming regions from dissolving after they condensed to form clusters of stars. We study the statistics of such compressive modes in an N-body model of the galaxy merger NGC 4038/39 (the Antennae) and show
The latest edition of the Swiss standard SIA181(2006) Protection against noise in Buildings [1], introduces a new methodology regarding the tests to be performed in new constructions for noise induced by human using service equipment in bathroom and kitchen. In this method, a specific pendling hammer has been developed especially for evaluating the decoupling efficiency of service equipment. The g
Many multifamily houses are produced by small or medium size enterprises (SME's). These developers produce a substantial number of residential units per year. They have normally limited resources and need to have easy access to cost - effective structural solutions. Typical buildings comprise two storeys and four to eight flats. Due to costs and production efficiency these buildings are produced i
The latest Swiss standard SIA181 (6-2006 edition [1]) introduces a new methodology regarding the tests to be performed in new constructions for assessing noise induced by the manipulation of service equipment in bathrooms and kitchens. However, this method has been developed especially for massive constructions. In this study, we are investigating the relevance of such method for timber frame buil
Various modal methods are frequently used to investigate the vibration pattern in construction elements of a building in the low frequency range. The experimental determination of time average transmission and reflection coefficient has been developed for the large scale building structures. In this study, we investigate a mock up of a wall/floor junction. The wave approach is combined with the co
