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71.
Reinhard Miller Dmitri Grigoriev Jürgen Krägel Alexander V. Makievski Valentin B. Fainerman Volodymyr I. Kovalchuk Libero Liggieri Francesca Ravera Michele Ferrari Eva Santini Giuseppe Loglio Victoria Dutschk Thodoris Karapantsios 《Microgravity science and technology》2006,18(3-4):104-107
The utilisation of particle-surfactants nanostructures as stabilising agents represents today the technologic and scientific frontier in the stabilisation of liquid films in emulsion and foams. This topic will be addressed by the proposal STEFAN (STabilisation of Emulsions and FoAms by Nanoparticles), proposed by European groups in the framework of the ESA AO-2004 for Life and Physical Sciences and Applied Research projects Similarly to what can be observed for surfactant-stabilised emulsions and foams, microgravity provides ideal conditions for the investigation of the hierarchy of involved objects: interfacial layer, liquid film, dispersed systems foam or emulsion. Microgravity experiments are planned by refurbishing the Experimental Container FASES for the ISS Fluid Science Laboratory and the facility FASTER for the European Drawer Rack, already under development in existing research programmes. Here the scientific guidelines of the project are presented together with examples and preliminary results on the effect of nano-particle-surfactant structures adsorbed at liquid interfaces. First experimental results have been achieved for particle monolayers at the water/air interface and a thermodynamic model was derived to describe the obtained surface pressure-area isotherms. 相似文献
72.
Lorenzo Repetto Mauro Parodi Marco Storace 《International Journal of Circuit Theory and Applications》2006,34(2):237-248
In this paper we propose a variational method to find out piecewise‐linear (PWL) approximations of non‐linear dynamical systems in view of their circuit implementations. The method is based on some significant trajectories of the dynamical system and provides reasonably accurate PWL approximations with a relatively low number of parameters. The effectiveness of the method is validated by applying it to the approximation of limit cycles (both stable and unstable) in the Bautin system. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
73.
Alexander V. Makievski Volodymyr I. Kovalchuk Jürgen Krägel Madine Simoncini Libero Liggieri M. Ferrari Piero Pandolfini Giuseppe Loglio Reinhard Miller 《Microgravity science and technology》2005,16(1-4):215-218
The present work shows the first experimental and theoretical results for investigations on the rheology of liquid films. The experiments are planned to be performed under microgravity conditions. This environment will allow forming films of different thickness, which is impossible under ground conditions due to drainage. Then the films are forced to harmonic oscillations of the film area so that the film elasticity can be measured as a function of frequency. The presented theoretical model demonstrates the main relationships to be solved under corresponding boundary conditions 相似文献
74.
Ferrari S. Frosio I. Piuri V. Borghese N.A. 《IEEE transactions on instrumentation and measurement》2005,54(4):1463-1470
A procedure for the real-time construction of three-dimensional (3-D) multiscale meshes from not evenly sampled 3-D points is described and discussed in this paper. The process is based on the connectionist model named hierarchical radial basis functions network (HRBF), which has been proved effective in the reconstruction of smooth surfaces from sparse noisy data points. The network goal is to achieve a uniform reconstruction error, equal to measurement error, by stacking noncomplete grids of Gaussians at decreasing scales. It is shown here how the HRBF properties can be used to develop a configuration algorithm, which produces a continuous surface in real time. In addition, the model is extended to automatically convert the continuous surface into a 3-D mesh according to an adequate error measure. 相似文献
75.
The Unified Problem-Solving Method
Development Language UPML 总被引:2,自引:1,他引:2
76.
B.E. Watts F. Leccabue G. Tallarida S. Ferrari M. Fanciulli G. Padeletti 《Journal of Electroceramics》2003,11(3):139-147
Reliability issues have hampered the adoption of ferroelectric thin films by the microelectronics industry. One of these is imprint, an important problem affecting the performance of ferroelectric non-volatile memories. This paper presents the effects of the low temperature pyrolysis step on the chemical and physical properties of SrBi2Ta2O9 films. A comparison of the hysteretic properties and composition profiles shows that control of the oxidising conditions during pyrolysis is critical to the dielectric properties. Data from this work and from the literature have been used to construct a model that explains the origin of surface depletion and segregation, self poling and as-grown imprint in ferroelectric films. 相似文献
77.
Multirobot motion coordination in space and time 总被引:5,自引:0,他引:5
Carlo Ferrari Enrico Pagello Jun Ota Tamio Arai 《Robotics and Autonomous Systems》1998,25(3-4):219-229
This paper describes a solution to the multirobot motion planning problem based on a decoupled analysis in the space domain and in the time domain. It investigates the practical use of the notion of motion plan quality and of the motion plan robustness measures for computing safe motions. The use of anytime algorithms allows one to evaluate the opportunity of looking for alternative solution paths by generating small variations of robot motions affecting both its geometrical path and its scheduled velocity. By using the concept of plan robustness, several alternative paths are generated and evaluated through various performance indices and impact factors, using heuristic rules. These indices allow one to know how much a variation affects a given plan. Finally, some recent experiments are outlined. 相似文献
78.
An approximating neural model, called hierarchical radial basis function (HRBF) network, is presented here. This is a self-organizing (by growing) multiscale version of a radial basis function (RBF) network. It is constituted of hierarchical layers, each containing a Gaussian grid at a decreasing scale. The grids are not completely filled, but units are inserted only where the local error is over threshold. This guarantees a uniform residual error and the allocation of more units with smaller scales where the data contain higher frequencies. Only local operations, which do not require any iteration on the data, are required; this allows to construct the network in quasi-real time. Through harmonic analysis, it is demonstrated that, although a HRBF cannot be reduced to a traditional wavelet-based multiresolution analysis (MRA), it does employ Riesz bases and enjoys asymptotic approximation properties for a very large class of functions. HRBF networks have been extensively applied to the reconstruction of three-dimensional (3-13) models from noisy range data. The results illustrate their power in denoising the original data, obtaining an effective multiscale reconstruction of better quality than that obtained by MRA. 相似文献
79.
Storm overflow structures in combined sewers are used to separate sewage from storm water. For subcritical approach flow, sideweirs are currently used; however, they often behave hydraulically poor. This study was conducted to explore a combined storm overflow structure able to improve the hydraulic performance of sewer sideweirs. Such a structure consists of a low-crested sideweir and a bottom opening just downstream from the sideweir end. First, the hydraulic design procedure is described, and then, based on laboratory experiments and by using the governing flow equations, the main hydraulic features are highlighted. The results indicate that the proposed device has advantageous characteristics in terms of hydraulic efficiency, reliability, and maintenance. 相似文献
80.
Anna Beatriz Sabino Ferrari George Azevedo de Oliveira Helena Mannochio Russo Luiza de Carvalho Bertozo Vanderlan da Silva Bolzani Diego Cunha Zied Valdecir Farias Ximenes Maria Luiza Zeraik 《International Journal of Food Science & Technology》2021,56(1):452-460
In this study, the chemical composition, total phenolic content and antioxidant activity (DPPH, ORAC and FRAP assays) of A. subrufescens and P. ostreatus, cultivated with handmade and commercials supplements, were compared. Additionally, the compounds ergosterol, saccharopine, and hexitol were identified in A. subrufescens by HPLC-MS/MS. The antioxidant compound p-coumaric acid and dihexoses was found in both mushroom species. A. subrufescens presented higher total phenolic content (73.8 ± 0.6 mg GAE 100 g−1) and antioxidant activity than P. ostreatus (16.6 ± 0.5 mg GAE 100 g−1). The handmade supplement based on the waste of noble grains presented statistically similar phenolic content to the mushrooms cultivated with commercial ones Spawn Mate II SE (86.1 ± 1.4 and 92.9 ± 0.3 mg GAE 100 g−1, respectively). Therefore, the results support the use of handmade supplements based on agro-wastes as a viable alternative to the use of high-cost commercial ones. 相似文献