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Operator 4.0: Industrial Augmented Reality, Interfaces and Ergonomics
Full text linkIl programma Industry 4.0, in Germania, e le corrispondenti iniziative internazionali continueranno a trasformare la forza e l’ambiente di lavoro nell’industria fino al 2025.
Parallelamente all'evoluzione del settore, la storia dell'interazione dell’operatori con le varie tecnologie di produzione industriale e digitale può essere riassunta come un'evoluzione generazionale verso la generazione dell’Operatore 4.0.
Questo lavoro di tesi mira ad applicare le tecnologie abilitanti di Industry 4.0 per progettare e sviluppare, metodi e applicazioni a supporto della figura di Operator 4.0 rispetto a tre delle sue otto sfaccettature: l'Augmented Operator, il Virtual Operator e l'Healthy Operator.
Nel Capitolo 1, presentiamo le ricerche svolte nel campo Industrial Augmented Reality. Descriviamo la tecnologia della Realtà Aumentata (AR) e la sua applicazione nel campo della Realtà Aumentata Industriale (IAR). Nel capitolo 2 presentiamo un prototipo di banco di lavoro badato su Spatial Augmented Reality (SAR) progettato nelle prime fasi di questa ricerca e descriviamo gli esperimenti effettuati per convalidare la sua efficienza come supporto per Operator 4.0.
Nel Capitolo 3 descriviamo gli esperimenti effettuati per ottimizzare la leggibilità del testo mostrato nelle interfacce AR per Optical See-Through Displays. In questa ricerca, proponiamo nuovi indici estratti dalle immagini di background, visualizzati su uno schermo LCD, e li confrontiamo con quelli proposti in letteratura attraverso un test utente specifico.
Nel Capitolo 4 presentiamo un framework AR per dispositivi palmari che aiuta gli utenti nella comprensione delle informazioni sugli impianti descritte tradizionalmente attraverso i Piping and Instrumentation Diagrams (P & ID) su supporto cartaceo.
Nel Capitolo 5 descriviamo la ricerca svolta nel campo delle Human Machine Interfaces relativa all'uso delle interfacce utente naturali in realtà virtuale. Abbiamo progettato e sviluppato un'interfaccia gestuale per la navigazione di tour virtuali costituiti da immagini sferiche. Abbiamo confrontato l'interfaccia sviluppata con una classica controllata da mouse per valutare l'efficacia di tale interfaccia in termini di accettazione e coinvolgimento degli utenti.
Nel Capitolo 6, descriviamo un framework generale per la progettazione di un vocabolario di gesti per la navigazione delle istruzioni tecniche nei manuali digitali per le operazioni di manutenzione. Viene anche proposta e utilizzata una procedura di validazione per confrontare i vocabolari gestuali in termini di fatica e carico cognitivo.
Nel Capitolo 7, trattiamo l'aspetto dell’Healthy Operator. Descriviamo la progettazione e lo sviluppo di uno strumento software semi-automatico in grado di monitorare l'ergonomia dell'operatore nell’ambiente di lavoro valutando la metrica Rapid Upper Limb Assessment (RULA). Descriviamo il design e lo sviluppo del nostro prototipo software, il K2RULA, basato su un sensore a basso costo, il Microsoft Kinect v2. Successivamente, convalidiamo il nostro strumento con due esperimenti. Nel primo, lo confrontiamo con un sistema di tracking ottico, il golden standard di settore. Nel secondo confrontiamo i risultati restituiti dal prototipo con quelli calcolati da un valutatore esperto.
Infine, traiamo le nostre conclusioni sul lavoro svolto e cerchiamo di tracciare un percorso per lo sviluppo futuro delle nostre ricerche.The German program Industry 4.0 and the corresponding international initiatives will continue to transform the industrial workforce and their work environment through 2025.
In parallel with the evolution of the industry, the history of the interaction of operators with various industrial and digital production technologies can be summarized as a generational evolution towards the Operator 4.0 generation.
This work aims at applying the enabling technologies of Industry 4.0 in order to design and develop, methods and applications supporting the figure of the Operator 4.0 with respect three out of her/his eight facets – the Augmented Operator, the Virtual Operator, and the Healthy Operator.
In Chapter 1, we introduce the researches carried out in the IAR field. We describe the Augmented Reality (AR) technology and its application in the field of the Industrial Augmented Reality (IAR). In chapter 2, we present a Spatial Augmented Reality (SAR) workbench prototype designed in the early stage of this research and we describe the experiments carried out to validate its efficiency as support to the Operator 4.0.
In Chapter 3, we describe the experiments carried out to optimize legibility of text shown in AR interfaces for optical see-through displays. In this research, we propose novel indices extracted from the background images, displayed on an LCD screen, and we compare them with those proposed in the literature by designing a specific user test.
In Chapter 4, we present an AR framework for handheld devices that enhance users in the comprehension of plant information traditionally conveyed through printed Piping and Instrumentation Diagrams (P&ID).
In Chapter 5 we describe the research carried out in the field of HMI related to the use of Natural User Interfaces in Virtual Reality. We designed and developed a gesture interface for navigation of virtual tours made-up of spherical images. We compared the developed interface with a classical mouse-controlled one to evaluate the effectiveness of such an interface in terms of user acceptance and user engagement.
In Chapter 6, we describe a general framework to design a mid-air gesture vocabulary for the navigation of technical instructions in digital manuals for maintenance operations. A validation procedure is also proposed and utilized to compare gesture vocabularies in terms of fatigue and cognitive load.
In Chapter 7, we treat the facet of the Healthy Operator. We describe the design and development of a semi-automatic software tool able at monitoring the operator ergonomics in the shop floor by assessing Rapid Upper Limb Assessment (RULA) metrics. We describe the design and development of our software prototype – the K2RULA - based on a low- cost sensor, the Microsoft Kinect v2 depth-camera. Subsequently, we validate our tool with two experiments. In the first one, we compared the K2RULA grand-scores with those obtained with a reference optical motion capture system. In the second experiment, we evaluate the agreement of the grand-scores returned by the proposed application with those obtained by a RULA expert rater.
Finally, we draw our conclusions regarding the work carried out and try to map out a path for the future development of our researches in these fields
Progressive high-fluence epithelium-on accelerated corneal crosslinking: a novel corneal photodynamic therapy for early progressive keratoconus
Full text linkPurpose: To assess the preliminary clinical results of a new, progressively higher fluence-pulsed light Epi-On accelerated crosslinking nomogram (PFPL M Epi-On ACXL) in the treatment of progressive keratoconus (KC). Setting: Siena Crosslinking Center, Siena, Italy. Methods: A prospective pilot open, non-randomized interventional study, including 32 eyes of 32 young-adult patients over 26 years old with Stages I-III progressive KC undergoing PFPL M Epi-On ACXL, was conducted. Riboflavin loading was performed by using Paracel I 0.25% for 4 min and Paracel II 0.22% for 6 min. The Avedro KXL System (Glaukos-Avedro, Burlington, USA) was used for pulsed-light accelerated crosslinking (ACXL) at air room 21% oxygenation and 13 min of UV-A irradiation. The treatment fluence was set at 7.2 J/cm2, 8.6 J/cm2, and 10.0 J/cm2 in corneas with baseline pachymetry <420 μm (group 1: 8 eyes), ≥ 420 μm <460 μm (group 2, 11 eyes), and ≥ 460 μm (group 3, 13 eyes), respectively. Uncorrected distance visual acuity (UDVA), best-spectacle corrected visual acuity (BSCVA), Scheimpflug corneal tomography, and anterior segment OCT (AS-OCT) data were collected at baseline and postoperatively at 1, 3, and 6 months. Results: UDVA and BSCVA improved in all groups (P ≤ 0.05). Maximum keratometry values (K max) showed a significant decrease in the 10.0 J/cm2 group (Δ −1.68 D). The coma (HOAs) value improved significantly by the sixth month in all groups. OCT average demarcation lines were 211 ± 19 μm in group 1, 245 ± 23 μm in group 2, and 267 ± 21 μm in group 3. Conclusions: The preliminary results show that pachymetry-based PFPL M Epi-On ACXL nomogram stabilizes ectasia progression. Higher fluence Epi-On ACXL increases CXL penetration, with better functional outcomes in the absence of complications
Chemically-boosted corneal cross-linking for the treatment of keratoconus through a riboflavin 0.25% optimized solution with high superoxide anion release
Full text linkThe purpose of this study was to evaluate the effectiveness and safety of a novel buffered riboflavin solution approved for corneal cross-linking (CXL) in progressive keratoconus and sec-ondary corneal ectasia. Following the in vivo preclinical study performed on New Zealand rabbits comparing the novel 0.25% riboflavin solution (Safecross®) containing 1% hydroxypropyl methyl-cellulose (HPMC) with a 0.25% riboflavin solution containing 0.10% EDTA, accelerated epithelium-off CXL was performed on 10 patients (10 eyes treated, with the contralateral eye used as control) through UV-A at a power setting of 9 mW/cm2 with a total dose of 5.4 J/cm2. Re-epithelialization was evaluated in the postoperative 7 days by fluorescein dye test at biomicroscopy; endothelial cell count and morphology (ECD) were analyzed by specular microscopy at the 1st and 6th month of follow-up and demarcation line depth (DLD) measured by anterior segment optical coherence to-mography (AS-OCT) one month after the treatment. We observed complete re-epithelization in all eyes between 72 and 96 h after surgery (88 h on average). ECD and morphology remained un-changed in all eyes. DLD was detected at a mean depth of 362 ± 50 μm, 20% over solutions with equivalent dosage. SafeCross® riboflavin solution chemically-boosted corneal cross-linking seems to optimize CXL oxidative reaction by higher superoxide anion release, improving DLD by a factor of 20%, without adverse events for corneal endothelium
Progressive high-fluence epithelium-on accelerated corneal crosslinking: a novel corneal photodynamic therapy for early progressive keratoconus
Full text linkPurpose: To assess the preliminary clinical results of a new, progressively higher
fluence-pulsed light Epi-On accelerated crosslinking nomogram (PFPL M Epi-On
ACXL) in the treatment of progressive keratoconus (KC).
Setting: Siena Crosslinking Center, Siena, Italy.
Methods: A prospective pilot open, non-randomized interventional study,
including 32 eyes of 32 young-adult patients over 26 years old with Stages I-
III progressive KC undergoing PFPL M Epi-On ACXL, was conducted. Riboflavin
loading was performed by using Paracel I 0.25% for 4min and Paracel II 0.22%
for 6min. The Avedro KXL System (Glaukos-Avedro, Burlington, USA) was used
for pulsed-light accelerated crosslinking (ACXL) at air room 21% oxygenation and
13min of UV-A irradiation. The treatment fluence was set at 7.2 J/cm2, 8.6 J/cm2,
and 10.0 J/cm2 in corneas with baseline pachymetry <420μm(group 1: 8 eyes),
420μm<460μm(group 2, 11 eyes), and 460μm(group 3, 13 eyes), respectively.
Uncorrected distance visual acuity (UDVA), best-spectacle corrected visual acuity
(BSCVA), Scheimpflug corneal tomography, and anterior segment OCT (AS-OCT)
data were collected at baseline and postoperatively at 1, 3, and 6 months.
Results:UDVA and BSCVA improved in all groups (P 0.05).Maximumkeratometry
values (K max) showed a significant decrease in the 10.0 J/cm2 group (1 −1.68
D). The coma (HOAs) value improved significantly by the sixthmonth in all groups.
OCT average demarcation lines were 211 ± 19μm in group 1, 245 ± 23μm in
group 2, and 267 ± 21μm in group 3.
Conclusions: The preliminary results show that pachymetry-based PFPL M
Epi-On ACXL nomogram stabilizes ectasia progression. Higher fluence Epi-On
ACXL increases CXL penetration, with better functional outcomes in the absence
of complications
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Customized Corneal Cross-Linking
No full textPersonalized accelerated crosslinking nomograms for the management of corneal ectasia were conceived after comparative analysis of demarcation lines and cell viability observed after customized accelerated epithelium-off crosslinking CXL treatments by spectral domain corneal OCT and scanning laser in vivo confocal microscopy matching all the clinical and instrumental data with mathematical models. Accelerated high-fluence Topography-guided CXL at 30 mW/cm2 UV-Power and Accelerated epithelium-off CXL with 9 and 15 mW/cm2 UV-A power with standardized Fluence of 5.4 J/cm2 were safe and effective demostrating a keratocytes apoptosis and demarcation line depth between 280 and 340 μm. The 30 mW ACXL showed a penetration with continuous and pulsed light between 150 and 200 μm. No endothelial damage was reported in any case. In vivo morphological studies demonstrated that Accelerated CXL allow a pachymetry-guided cutomization of CXL maintainig the standard Fluence of 5.4 J/cm2 and a total treatment time under 20 min. Moreover a pachymetry-guided ACXL nomogram (M nomogram) developed by Mazzotta C and Friedman M matching the physical and mathematical calculations with the miscostructural IVCM and OCT observations of demarcation lines depths allow an efficacous CXL management of primary and iatrogenic ectatic corneas also allowing a safe management of thin ectatic corneas
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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