Designing Touchless Gestural Interfaces for Public Displays

Nell’ultimo decennio, molti autori hanno studiato la possibilità di utilizzare le interfacce a gesti come strumento innovativo per supportare l’interazione con i computer. Inoltre, le recenti innovazioni tecnologiche hanno permesso di installare display interattivi in ambienti privati e pubblici. Tuttavia, l’interattività di tali display è spesso basata sull’uso di touchscreen, mentre tecnologie come i dispositivi Kinect-like vengono adottate molto più raramente, soprattutto se si considera l’ambito dei display pubblici. Al giorno d’oggi, l’opportunità di studiare le interfacce touchless per i display pubblici è diventata concreta, e rappresenta il campo di studio di diversi ricercatori. L’obiettivo principale di questa tesi è quello di descrivere e studiare i problemi legati alla progettazione e all’implementazione di un’interfaccia grafica dedicata all’interazione touchless a gesti con display pubblici. Ciò implica la necessità di superare alcuni problemi tipici, sia dei display pubblici (ad esempio, l’interaction blindness e l’usabilità immediata), che delle interfacce touchless (per esempio, comunicare che l’interattività è gestuale). La tesi, inoltre, include uno studio che analizza quanto la presenza dell’Avatar possa influire sulle interazioni degli utenti, in termini di carico di lavoro percepito, e quanto essa sia in grado di incoraggiare le interazioni a due mani. Poiché ABaToGI è stata progettata per i display pubblici, l’interfaccia è stata anche inclusa in un’installazione pubblica per essere valutata sul campo. I risultati di questo studio (e di quelli precedenti) sono stati quindi riassunti al fine di sviluppare una serie di linee guida per lo sviluppo di nuove interfacce touchless a gesti basata sull’uso di un Avatar. La tesi si conclude con alcuni spunti di ricerca per il futuro.In the last decade, many authors have investigated and studied touchless and gestural interactions as a novel tool for interacting with computers. Moreover, technological innovations have allowed for installations of interactive displays in private and public places. However, interactivity is usually implemented by touchscreens, whereas technologies able to recognize body gestures are more rarely adopted, especially in integration with commercial public displays. Nowadays, the opportunity to investigate touchless interfaces for such systems has become concrete and studied by many researchers. Indeed, this interaction modality offers the possibility to overcome several issues that cannot be solved by touch-based solutions, e.g. keeping a high hygiene level of the screen surface, as well as providing big displays with interactive capabilities. The main goal of this thesis is to describe the design process for implementing touchless gestural interfaces for public displays. This implies the need for overcoming several typical issues of both public displays (e.g. interaction blindness, immediate usability) and touchless interfaces (e.g. communicating touchless interactivity). To this end, a novel Avatar-based Touchless Gestural Interface (or ABaToGI) has been developed, and its design process is described in the thesis, along with the user studies conducted for its evaluation. Moreover, the thesis analyzes how the presence of the Avatar may affect user interactions in terms of perceived cognitive workload, and if it may be able to foster bimanual interactions. Then, as ABaToGI was designed for public displays, it has been installed in an actual deployment in order to be evaluated in-the-wild (i.e. not in a lab setting). The resulting outcomes, along with the previously described studies, have been used to introduce a set of design guidelines for developing future touchless gestural interfaces, with a particular focus on Avatar-based ones. The results of this thesis provide also a basis for future research, which concludes this work

Calibration of the AquaCrop model for winter wheat using MODIS LAI images

In semi-arid environments vegetation density and distribution is of considerable importance for the hydrological water balance. A number of hydrological models exploit Leaf Area Index (LAI) maps retrievedby remote sensing as a measure of the vegetation cover, in order to enhance the evaluation of evapotran-spiration and interception losses. On the other hand, actual evapotranspiration and vegetation development can be derived through crop growth models, such as AquaCrop, developed by FAO (Food and Agricultural Organization), which allows the simulation of the canopy development of the main field crops. We used MODIS LAI images to calibrate AquaCrop according to the canopy cover development of winter wheat. With this aim we exploited an empirical relationship between LAI and canopy cover. In detail Aquacrop was calibrated with MODIS LAI maps collected between 2008 and 2011, and validated with reference to MODIS LAI maps of 2013-2014 in Rocchetta Sant'Antonio and Sant'Agata, two test sites in the Carapelle watershed, Southern Italy. Results, in terms of evaluation of canopy cover, provided improvements. For example, for Rocchetta Sant'Antonio, the statistical indexes vary from r = 0.40, ER = 0.22, RMSE = 17.28 and KGE = 0.31 (using the model without calibration), to r = 0.86, ER = 0.08, RMSE = 6.01 and KGE 0.85 (after calibration). © 2015 Elsevier B.V

Touch or Touchless? Evaluating Usability of Interactive Displays for Persons with Autistic Spectrum Disorders

Interactive public displays have been exploited and studied for engaging interaction in several previous studies. In this context, applications have been focused on supporting learning or entertainment activities, specifically designed for people with special needs. This includes, for example, those with Autism Spectrum Disorders (ASD). In this paper, we present a comparison study aimed at understanding the difference in terms of usability, effectiveness, and enjoyment perceived by users with ASD between two interaction modalities usually supported by interactive displays: touch-based and touchless gestural interaction. We present the outcomes of a within-subject setup involving 8 ASD users (age 18-25 y.o., IQ 40-60), based on the use of two similar user interfaces, differing only by the interaction modality. We show that touch interaction provides higher usability level and results in more effective actions, although touchless interaction is more effective in terms of enjoyment and engagemen

Palmprint principal lines extraction

The palmprint recognition has become a focus in biological recognition and image processing fields. In this process, the features extraction (with particular attention to palmprint principal line extraction) is especially important. Although a lot of work has been reported, the representation of palmprint is still an open issue. In this paper we propose a simple, efficient, and accurate palmprint principal lines extraction method. Our approach consists of six simple steps: normalization, median filtering, average filters along four prefixed directions, grayscale bottom-hat filtering, combination of bottom-hat filtering, binarization and post processing. The contribution of our work is a new method for palmprint principal lines detection and a new dataset of hand labeled principal lines images (that we use as ground truth in the experiments). Preliminary experimental results showed good performance in terms of accuracy with respect to three methods of the state of the art

Predicting mid-air gestural interaction with public displays based on audience behaviour

© 2020 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/.Knowledge about the expected interaction duration and expected distance from which users will interact with public displays can be useful in many ways. For example, knowing upfront that a certain setup will lead to shorter interactions can nudge space owners to alter the setup. If a system can predict that incoming users will interact at a long distance for a short amount of time, it can accordingly show shorter versions of content (e.g., videos/advertisements) and employ at-a-distance interaction modalities (e.g., mid-air gestures). In this work, we propose a method to build models for predicting users’ interaction duration and distance in public display environments, focusing on mid-air gestural interactive displays. First, we report our findings from a field study showing that multiple variables, such as audience size and behaviour, significantly influence interaction duration and distance. We then train predictor models using contextual data, based on the same variables. By applying our method to a mid-air gestural interactive public display deployment, we build a model that predicts interaction duration with an average error of about 8 s, and interaction distance with an average error of about 35 cm. We discuss how researchers and practitioners can use our work to build their own predictor models, and how they can use them to optimise their deployment.Peer reviewe

Supporting tourism with public interactive displays

Interactive displays are common in public and semi-public areas, such as museums, shopping malls, train stations, and even on streets. Especially with the emergence of new ways of interaction, interactive displays could be introduced to popular tourist attractions to support tourism. The aim of this tutorial is to prepare its participants for designing such interactive public displays. The tutorial will first introduce participants to state of the art in interactive public displays. This will be followed by a city tour where a number of local attractions are visited. Finally, the participants will brainstorm and create concepts for novel interactive public displays that aim to improve the experience of visiting tourist attractions

Child-display interaction: exploring avatar-based touchless gestural interfaces

During the last decade, touchless gestural interfaces have been widely studied as one of the most promising interaction paradigms in the context of pervasive displays. In particular, avatars and sil- houettes have been proved to be effective in communicating the touchless gestural interactivity supported by displays. In the paper, we take a child-display interaction perspective by exploring avatar- based touchless gestural interfaces. We believe that large displays offer an opportunity to stimulate child experience and engagement, for instance when learning about art, as well as bringing a number of challenges. The purpose of this study is twofold: 1) identifying the relevant aspects of children’s interactions with a large display based on a touchless avatar-based interface, and 2) understanding the impact on recalling the content that arises from the interaction. We engaged 107 children over a period of five days during a public event at the university premises. Collected data were analyzed, and the outcomes transformed into three lessons learnt for informing the future design

Toxic metals in Loggerhead sea turtles (Caretta caretta) stranded freshly dead along Sicilian coasts

Abstract Background: The Loggerhead sea turtle (Caretta caretta) is a marine reptile belonging to a monophyletic group of chelonians. As these animals are long-lived, they have the ability to accumulate pollutants. Aim: To collect epidemiological data on toxic metals in marine Loggerhead sea turtles. Materials and Methods: Forty Loggerhead sea turtles comprising 25 males and 15 females stranded freshly dead between 2013 and 2018 along the coasts of Sicily, Southern Italy, were examined for arsenic, cadmium, and lead accumulation in muscle and adipose tissues by means of a validated ICP-MS method. A modified K index as a growth condition factor, namely Fulton's K index, was used. Samples were tested in duplicate. A Wilcoxon rank sum test was carried out to evaluate metal contents differences between muscle and adipose tissues and between genders. Results: The Fulton's K index suggested a good body condition of the C. caretta recovered with mean values of 5.34±3.40 (n=40; ±SD). Detectable concentrations of lead were found in 70% of the samples analysed with mean values of 0.65±1.67 mg/kg wet weight and 0.51±1.29 mg/kg wet weight in muscle and adipose tissues, respectively. No significant differences in arsenic, cadmium, and lead were detected between genders. In addition, no significant correlation was found between modified K index and concentrations of arsenic, cadmium, and lead. Clinical relevance: Findings on muscle and adipose tissues suggest chronic exposure of Caretta caretta to high concentrations of especially lead which might negatively affect health and welfare of these marine turtles although body condition was good

A randomised controlled trial of a school-based intervention to prevent tobacco use among children and adolescents in Italy

Aim: A randomised field trial was conducted to evaluate a school-based programme to prevent tobacco use in children and adolescents. Subject and methods: The trial included 534 children and 308 adolescents who were randomly selected to receive or not to receive the prevention programme. The prevention programme included: (a) health facts and the effect of smoking, (b) analysis of the mechanisms underlying intiation of smoking and (c) refusal skills training to deal with the social pressures to smoke. A questionnaire was administered before the intervention programme and 2 years later. Results: The prevalence rates of smoking in both groups of children and adolescents were increased at the end of the study. Anyway, the difference of smoking prevalence between the intervention and control groups was statistically significant only for the children’s group (from 18.3 to 18.8% for the intervention group and from 17.8 to 26.9% in the control group) (p = 0.035). As regards reasons that induced the start of smoking, there was a significant increase of the issue "because smokers are fools" (p = 0.004 for children; p < 0.001 for adolescents) and "because smokers are irresponsible" (p ≤ 0.001 for both children and adolescents) in the experimental groups. Conclusion: The results suggest that a school-based intervention programme addressing tobacco use among children and adolescents, based on the development of cognitive and behavioural aspects, can be effective. After 1 year of intervention, smoking prevalence was significantly lower in children belonging to the intervention group than in children not randomised to intervention. Targeting young children before they begin to smoke can be a successful way of prevention