Search results for "Lighting"
showing 10 items of 140 documents
The goldfish--a colour-constant animal.
1996
A series of either thirteen or fifteen coloured test fields with hues from blue through grey to yellow were presented on a black background. Goldfish were trained on a bluish-grey test field by food reward. In the training situation, the setup with the coloured papers was illuminated with white light. In the test situation, the colour of the illumination was changed to blue or yellow. In both test illuminations the goldfish preferred the training field in the same way as under white illumination despite the fact that this test field stimulated the cone types very differently from the training situation. As test fields were present that excited the cones in exactly the same way as under whi…
Energy saving and user satisfaction for a new advanced public lighting system
2019
Abstract The retrofit of urban lighting systems is often an advantageous means of achieving notable energy savings and improvements in the quality of light. User habits, expectations and lifestyle can contribute to the design of these systems, for example in deciding on the most appropriate control strategies or the light quality. The influence of such variables can be extended to the overall system performance. This paper presents a method of street lighting design based on two kinds of analysis carried out in a defined test area: measurements (by means of a monitoring study) and user preferences (by means of a survey). The results of this data analysis create the basis for the final desig…
Explainable Post-Occupancy Evaluation Using a Humanoid Robot
2020
The paper proposes a new methodological approach for evaluating the comfort condition using the concept of explainable post occupancy to make the user aware of the environmental state in which (s)he works. Such an approach was implemented on a humanoid robot with social capabilities that aims to enforce human engagement to follow recommendations. The humanoid robot helps the user to position the sensors correctly to acquire environmental measures corresponding to the temperature, humidity, noise level, and illuminance. The distribution of the last parameter due to its high variability is also retrieved by the simulation software Dialux. Using the post occupancy evaluation method, the robot …
Vision system for defect imaging, detection, and characterization on a specular surface of a 3D object
2002
Abstract A vision system capable of imaging, detecting, and characterizing defects onto highly reflective, non-plane surfaces, is presented in this paper. Defects are typically dust, and hair located under the metallic layer of packaging products used in cosmetic industries. The vision system comprises an innovative lighting solution to reveal defects onto highly reflective non-plane surfaces. Several image acquisitions are performed to build a synthetic image, where defects clearly appear white on a mid-gray background. Our lighting system allows imaging defects on various-shaped objects. The vision system measures the defect size to make a decision on the product rejection. The authors as…
Definition and Assessment of a BAC Factor for Estimating Electrical Consumption of Outdoor Lighting
2018
The BAC factors method was introduced by the international Standard EN 15232 for a rough evaluation of energy savings in buildings obtained thanks to automation. The above standard considers the building's services such as heating, cooling, ventilation and lighting and takes into account automation on the basis of assumed usage profile for the related technical installations. However, the standard does not refer specifically to the automation of outdoor lighting systems such as those serving gardens, entrance walkways and passages around the building and supplied by it. In this paper, the authors propose a method for evaluation an outdoor BAC factor for lighting system considering various s…
Environmental sustainability in non-residential buildings by automating and optimization LENI index
2018
Directive 2002/91 / EC as amended by 2010/31 / EU introduces procedures for energy certification aimed to determine, through the numerical indicators, the overall energy efficiency of the buildings, but notes the thermal and electric consumption. Often, the power consumption is incorrectly underestimated, this consumption would to be considered with great attention. In fact, compared to a committed capacity of less, compared to thermal plants, have times of utilization often far higher, leading to energy requirements to levels similar or even higher than those thermal, being the conversion factor of the electrical energy increasingly high. Leaving aside the procedural scheme energy certific…
Smart city and public lighting
2015
The smart city is increasingly becoming a concept of reference for what concerns the planning and the spatial development of cities. The concept of smart city cannot be easily standardized. It is based on a multi-service and multi-sectorial planning regarding various urban functions (energy, mobility, waste, etc.) and places them under a common denominator: the use of advanced technologies for minimizing resources consumption and simultaneously increase the quality of life of the citizens. This paper aims to give an overview on the concept of smart city and outline what, at present, are the main intervention areas considered at European level. Then the paper focuses on the public lighting t…
On the Applicability of the Space Syntax Methodology for the Determination of Street Lighting Classes
2020
Street lighting plays a crucial role in a city’s night landscape and in urban traffic management, influencing users’ comfort and safety. To contain costs of public street lighting systems and to avoid energy waste, illuminance levels on road surfaces must be adequate to fit actual traffic volumes, as prescribed by regulations. This is true not only for motorized roads but also for sidewalks, paths, and pedestrian areas. Regulations in force establish a relationship between road traffic volumes and minimum illuminance levels through the lighting classes selection procedure. Lighting classes selection is based on various para meters among which traffic volume is the most difficult to evaluate…
Assessment of the Entropy of Spatial and Time Distributions of Rooms Daylighting: A Possible Tool for a Sustainable Design
2015
The indoor visual comfort of subjects faced with indoor ambient lighting varies with the position of the subject and is not constant over time. Average performance indexes, such as the mean value of Daylight Factor and Daylight Autonomy, are commonly used to analyse lighting distribution. These indexes, however, don’t properly take into account either the spatial or the time distribution of values affecting the non-uniformity of environmental lighting. Indeed, these are limited to the definition of a mean value or to the assessment of time availability of daylighting. This paper examines spatial and temporal non-uniformities in indoor lighting as possible causes of discomfort for occupants.…
Liquid crystal spatial light modulator with very large phase modulation operating in high harmonic orders.
2013
Unusually large phase modulation in a commercial liquid crystal spatial light modulator (LCSLM) is reported. Such a situation is obtained by illuminating with visible light a device designed to operate in the infrared range. The phase modulation range reaches 6π radians in the red region of the visible spectrum and 10π radians in the blue region. Excellent diffraction efficiency in high harmonic orders is demonstrated despite a concomitant and non-negligible Fabry–Perot interference effect. This type of SLM opens the possibility to implement diffractive elements with reduced chromatic dispersion or chromatic control.