From Models to Simulations

This book analyses the impact computerization has had on contemporary science and explains the origins, technical nature and epistemological consequences of the current decisive interplay between technology and science: an intertwining of formalism, computation, data acquisition, data and visualization and how these factors have led to the spread of simulation models since the 1950s. Using historical, comparative and interpretative case studies from a range of disciplines, with a particular emphasis on the case of plant studies, the author shows how and why computers, data treatment devices and programming languages have occasioned a gradual but irresistible and massive shift from mathematical models to computer simulations

Skylab experiments. Volume 6: Mechanics

Skylab program activities are presented in a form adapted to instruction of high school students. The overall goals of the program are discussed. The specific accomplishments of the mechanics investigations are described. The subjects involved are as follows: (1) evaluation of mobility aids, (2) mass measurement devices, and (3) space guidance crew/vehicle disturbances

A community environment design hypertool. Application to sustainable cities interaction regulation

International audienceThis paper develops an innovative structure of knowledge collaboration forms that allows effective and creative collaboration among the actors along territorial design process. To contribute to the development of the social dimension of the sustainable development, we investigate a new methodology and computational tools for understanding and facilitating multi-disciplinary, cross-cultural collaboration in sustainable architectural-, urban- land- and ambient-scape design, through evaluating collaboration among project developers, local authorities, architects, engineers, contractors, building inspectors, clients and future users. Therefore, this proposed integrative tool increases the pool of knowledge and skills available to undertake activities that exceed the capacities of any single person or organization on its own, thus making possible the design and construction of complex skills, especially buildings and ambiences in urban or suburban environmen

Aerosol Particle Bounding in Cascade Impactors

Particle deposition characteristics were observed from the aerosol sampling results of a UNICO cascade impactor. A simple model of particle motion combined with Hiemenz flow of stagnation flow on a flat plate were developed and discussed. Both results and analysis were compared to recent models on particle bouncing errors or secondary deposition which included vortices formation around the edge of the slot, back spin (Magnus effect), and hydrodynamic conditions of the particles. The analysis was limited to a laminar inviscid and incompressible case. The main obstacle in the observation was the fact that impactor nozzles were unsymmetrical to a considerable degree, thereby deviating particle trajectory significantly from the predicted situation

Oceanic lithosphere and asthenosphere: The thermal and mechanical structure

A coupled thermal and mechanical solid state model of the oceanic lithosphere and asthenosphere is presented. The model includes vertical conduction of heat with a temperature dependent thermal conductivity, horizontal and vertical advection of heat, viscous dissipation or shear heating, and linear or nonlinear deformation mechanisms with temperature and pressure dependent constitutive relations between shear stress and strain rate. A constant horizontal velocity u sub 0 and temperature t sub 0 at the surface and zero horizontal velocity and constant temperature t sub infinity at great depth are required. In addition to numerical values of the thermal and mechanical properties of the medium, only the values of u sub 0, t sub 0 and t sub infinity are specified. The model determines the depth and age dependent temperature horizontal and vertical velocity, and viscosity structures of the lithosphere and asthenosphere. In particular, ocean floor topography, oceanic heat flow, and lithosphere thickness are deduced as functions of the age of the ocean floor

Experimental and numerical investigation of the earthquake response of crane bridges

© 2014 Elsevier Ltd. The experimental and numerical response of crane bridges is studied in this work. To this end, an experimental campaign on a scale model of an overhead crane bridge was carried out on the shaking table of CEA/Saclay in France. A special similarity law has been used which preserves the ratios of seismic forces to friction forces and of seismic forces to gravity forces, without added masses. A numerical model, composed of beam elements, which takes into account non-linear effects, especially impact and friction, and simulates the earthquake response of the crane bridge, is presented. The comparison of experimental and analytical results gives an overall satisfactory agreement. Finally, a simplified model of the crane bridge, with only a few degrees of freedom is proposed