Optical wireless based on high brightness visible LEDs

This paper is on a novel use of lighting or signaling devices constructed by light-emitting diodes (LEDs). The idea is on their concurrent use for simultaneous signaling and communications. The visible light from LEDs can be modulated and encoded with audio or data signal. Hence, an LED indicator lamp or traffic light can become an information broadcasting device. Such a system made up of high brightness visible LEDs can provide the function of open space, wireless broadcasting of audio or data signal. An implemented system with experimental results is shown. A portable receiver is designed to demodulate the optically transmitted information. The distance for audio transmission of an LED traffic light can reach over 20m. The optical link employs intensity modulation with direct detection. The system is limited to line-of-sight communications. However, this concurrent use of LEDs will open up many new applications.published_or_final_versio

LED wireless

High-brightness light-emitting diodes (LEDs) are getting more popular and are opening up a number of new applications. In this paper, the novel idea based on the fast switching of LEDs and the modulation of visible light is developed into a new kind of information system. A visible-LED audio system that makes use of visual-light rays to transmit audio messages to a remotely located receiver is described. Such a system made up of high-brightness visible LEDs can provide the function of open space, wireless broadcasting of audio signals. It can be used as an information beacon for short-distance communication.published_or_final_versio

Mapping Accessible Paths in the City Using Collective Intelligence

New information and communication technologies (ICTs) have an increasingly stronger role in people\u27s lives, especially after the commoditization of smartphones. They affect many aspects of everyday life, including urban mobility. Some applications, including Waze, benefit from the collective intelligence (CI) of the crowds to gather the information they need to provide users with good advice on the routes to follow. But they are mainly focused on roads and streets, giving little information on the quality of sidewalks, which are essential to pedestrians, people on wheelchairs and blind people. With the intention to improve the mobility of citizens with special needs, we developed the prototype of an application that allows users themselves to update accessibility maps, tagging obstacles and also indicating the existence of resources that contribute to improve the mobility of people with special needs in urban spaces. Tests in a controlled environment helped to debug the application’s functionalities, before members of the intended target group of users were finally exposed to it. Results are promising, as users were able to include relevant data by themselves and seem motivated to keep doing so, due a sense of utility, social facilitation or simply due to altruism, as anticipated by the CI literature. One unexpected outcome was that impaired users are more excited about the potential the application has to give visibility to the challenges they face than with the actual improvement it can bring to their mobility

The Design of Reliable Protocols for Wireless Traffic Signal System

Electronic traffic signal has the advantage of being easily visible to machines. It is expected to augment the traditional traffic light system in future intelligent transportation environments, where intelligent vehicles interact with each other and with traffic systems and give informed advisories to drivers. One problem with wireless signals is that they are essentially omnidirectional. Even if one uses directional wireless signaling source, it is not clear how any recipient of a signal can reliably determine whether the signal is meant for him or her, in the presence of signal reflections. In this paper, we present a basic electronic traffic signaling protocol framework and two reliable protocols for intersection traffic signal and stop sign signal. These protocols enable recipient vehicles to robustly differentiate the signal’s designated directions despite of potential threats(confusions) caused by reflections. We demonstrate how touse one of the protocol to construct a sample application: a red-light alert system. We also address potential inconsistency threats caused by the uncertainty of location system being used and discuss means to handle them

Vocal-auditory feedback and the modality transition problem in language evolution

This is a pre-print version. This article has been published in Reti Saperi Linguaggi, 1/2016 a. 5 (9), 157–178, [DOI: 10.12832/83923]. Copyright Società editrice il Mulino. The publisher should be contacted for permission to re-use or reprint the material in any form.The gestural theories, which see the origins of (proto)linguistic communication not in vocalization but rather in manual gesture, have come to take center stage in today’s academic reflection on the roots of language. The gestural theories, however, suffer from a near-fatal problem of the so-called «modality switch», i.e. of how and why language could have transferred from the mostly-visual to the mostly-vocal form that it now has in human societies almost universally. In our paper, we offer a potential and partial solution to this problem. We take as our starting point a gestural scenario on which emerging language-like communication involves orofacial gestures, and we complement such a scenario with the inclusion of vocal-auditory feedback, which aids signal production. Such benefits of more articulatory precision that accrue to the signal producersmight have constituted one reason behind supplementing orofacial gestures with sound and so increasing the role of vocalization in the emerging (proto)language

Visual Impairment and Blindness

Blindness and vision impairment affect at least 2.2 billion people worldwide with most individuals having a preventable vision impairment. The majority of people with vision impairment are older than 50 years, however, vision loss can affect people of all ages. Reduced eyesight can have major and long-lasting effects on all aspects of life, including daily personal activities, interacting with the community, school and work opportunities, and the ability to access public services. This book provides an overview of the effects of blindness and visual impairment in the context of the most common causes of blindness in older adults as well as children, including retinal disorders, cataracts, glaucoma, and macular or corneal degeneration