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51.
Future generation cars will be characterized by a wide range of Information Technology (IT) services providing safety and infotainment. This makes the car an information intensive environment where the visual channel is overloaded, putting the safety of drivers and passengers in jeopardy. We propose the use of a 3D auditory display to provide information from the Advanced Driver Assistance Systems. This reduces the eye-off-road time, exploiting the human capability to associate sounds with positions in space. Preliminary lab tests reveal the suitability of this approach. The system still has to be carefully tuned and personalized to achieve usability and reliability, but we think that it provides a complementary channel that is specially useful in low visibility conditions.  相似文献   
52.
This paper reports a three-substrate steady-state integrated model, whose unknowns are expressed in explicit terms once concentrations of nitrogen compounds in the effluent flow are fixed. The model can be applied both to design and to upgrade wastewater treatment plants. The model is also able to evaluate the flexibility of existing wastewater treatment plants, which represents the capacity of the system to operate under different working conditions caused by increases in influent load or reductions in effluent quality standards. In this case the admissible variation of influent load or effluent concentration can be measured using suitable dimensionless flexibility indexes.List of symbols Q influent flow [L3 T–1] - R1 sludge recycle flow ratio - R2 aerated mixed liquor recycle flow ratio - VD denitrification reactor volume [L3] - VN nitrification reactor volume [L3] - S biodegradable organic substrate concentration [M L–3] - N-NH4 ammonia nitrogen concentration [M L–3] - N-NO3 nitrate nitrogen concentration [M L–3] - Ntot total nitrogen concentration [M L–3] - O2 oxygen concentration in the nitrification reactor [M L–3] - XH heterotrophic biomass concentration [M L–3] - XAUT autotrophic biomass concentration [M L–3] - maximum removal rate of biodegradable organic substrate for an assigned value of temperature [T–1] - maximum removal rate of nitrate for an assigned value of temperature [T–1] - maximum removal rate of ammonia nitrogen for assigned values of pH and temperature [T–1] - S removal rate of biodegradable organic substrate [T–1] - D removal rate of nitrate [T–1] - N removal rate of ammonia nitrogen [T–1] - KS saturation coefficient for biodegradable organic substrate [M L–3] - KD saturation coefficient for nitrate [M L–3] - KSD saturation coefficient for organic substrate in the denitrification kinetic [M L–3] - KN saturation coefficient for ammonia nitrogen [M L–3] - saturation coefficient for oxygen [M L–3] - YH yield coefficient for heterotrophic microorganisms in the biodegradable organic substrate removal process - YD yield coefficient for heterotrophic microorganisms in the nitrate nitrogen removal process - YAUT yield coefficient for autotrophic microorganisms in the ammonia nitrogen removal process - (XH)r heterotrophic biomass concentration in the recycle sludge [M L–3] - (XAUT)r autotrophic biomass concentration in the recycle sludge [M L–3] - biodegradable organic mass consumption for unitary nitrate nitrogen mass reduction in the denitrification reactor - nitrogen consumption in the biodegradable organic oxidation process by mean of heterotrophic biomass  相似文献   
53.
The Layer-Oriented Simulation Tool (LOST) is a numerical simulation code developed for analysis of the performance of multiconjugate adaptive optics modules following a layer-oriented approach. The LOST code computes the atmospheric layers in terms of phase screens and then propagates the phase delays introduced in the natural guide stars' wave fronts by using geometrical optics approximations. These wave fronts are combined in an optical or numerical way, including the effects of wave-front sensors on measurements in terms of phase noise. The LOST code is described, and two applications to layer-oriented modules are briefly presented. We have focus on the Multiconjugate adaptive optics demonstrator to be mounted upon the Very Large Telescope and on the Near-IR-Visible Adaptive Interferometer for Astronomy (NIRVANA) interferometric system to be installed on the combined focus of the Large Binocular Telescope.  相似文献   
54.
The first step in a video indexing process is the segmentation of videos into meaningful parts called shots. In this paper we present a formal model of the video shot segmentation process. Starting from a mathematical characterization of the most common transition effects, a video segmentation algorithm capable to detect both abrupt and gradual transitions is proposed. The proposed algorithm is based on the computation of an arbitrary similarity measure between consecutive frames of a video. The algorithm has been tested adopting a similarity metric based on the Animate Vision theory and results have been reported.  相似文献   
55.
The purpose of this study is to see in which forms and under which conditions social presence turns into collaboration. Eight couples were asked to find some objects in a virtual environment in which collaboration was allowed but not mandatory. The qualitative analysis of the video recordings shows that all participants resorted to collaboration in forms that were justified by the requirements of the task, the environmental affordances and the different expertise.
Luciano GamberiniEmail: Phone: +39-049-8276605Fax: +39-049-8276600
  相似文献   
56.
This paper describes an approach to the acquisition and representation of information on 3D painted surfaces (usually frescoes) based on the tassellation and mosaicing of the whole surface. The acquisition is carried out using an active vision system specifically designed for these purposes. In this paper, particular emphasis is placed on the mosaicing procedure of the acquired images, which, while conceptually simple, allows one to obtain very good results thanks to the effective exploitation of the features of the acquisition system. A careful qualitative and quantitative analysis of the performances of the system, obtained through tests on real scenes in the laboratory, is also presented.Received: 28 May 2001, Accepted: 8 November 2002, Published online: 18 June 2003 Correspondence to: Paolo GrattoniMassimiliano Spertino: With I.R.I.T.I. under grant N.202.12484 of the Italian Safeguard of Cultural Heritage C.N.R. project.  相似文献   
57.
This paper presents the true three-colour photoceramic, introduced by the authors since 1992, which allows wide new possibilities in the field of the ceramic decoration, for reproduction on ceramic (majolica, porcelain, earthenware, etc.) surfaces of images either photographic or painted images or even directly coming from computer-made image files. The correspondent technological process used to produce this kind of decoration involves new manufacturing procedures and the use of unusual devices. The physical principle involved in obtaining the formation of the image is based on the well-known physiological tristimulus effect, which is founded on a consolidated theory and practice utilised for classical photographic and TV reproduction. The novelty consists in having introduced this technique in the ceramic decoration field. To distinguish the technique described here from that already known as polychromatic, based on a careful and artistic hand-painting technique (but an artefact based on the operator's fantasy), we have called it: true three-colour photoceramic process (the equivalent of the three-colour printing technique). Besides the due treatment of already known physical concepts, some technological problems are reported and discussed, which arose during the years of utilisation of this new technique. The behaviour in situ of true three-coloured photoceramics is also discussed here, in the light of many years of production and application. Physical and chemical aspects are considered, to further develop and improve this new technology of images reproduction.  相似文献   
58.
The paper deals with the optimisation of a tapered tubular steel component to be used as an energy-absorbing device in the front structure of a vehicle body. Aim of the optimisation problem is the minimisation of a load uniformity parameter evaluated as the ratio between the maximum and the average crushing loads. The optimisation problem takes into account two design variables describing a tapered geometrical configuration, the diameter of the component at one of its bounds and the tapering length. Two improved geometrical configurations have been found and have been experimentally tested to verify the numerical results with impact velocities up to 10 m/s.  相似文献   
59.
Trajectory planning and tracking are crucial tasks in any application using robot manipulators. These tasks become particularly challenging when obstacles are present in the manipulator workspace. In this paper a n-joint planar robot manipulator is considered and it is assumed that obstacles located in its workspace can be approximated in a conservative way with circles. The goal is to represent the obstacles in the robot configuration space. The representation allows to obtain an efficient and accurate trajectory planning and tracking. A simple but effective path planning strategy is proposed in the paper. Since path planning depends on tracking accuracy, in this paper an adequate tracking accuracy is guaranteed by means of a suitably designed Second Order Sliding Mode Controller (SOSMC). The proposed approach guarantees a collision-free motion of the manipulator in its workspace in spite of the presence of obstacles, as confirmed by experimental results.  相似文献   
60.
The results of an experimental investigation on epoxy-joined CVD SiC and alumina tested in shear and apparent shear mode by four different configurations are presented. Ceramics have been joined by an epoxy adhesive (AV119), which is not to be considered as the final joining material for high temperature applications, but just as a model brittle joining material chosen to obtain several joined samples in a reasonable time. Advantages and disadvantages of each configuration are discussed and compared to results obtained with the same epoxy-joined carbon/carbon composites, tested by the same shear tests.  相似文献   
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