A metrological characterization of the Kinect V2 time-of-flight camera

A metrological characterization process for time-of-flight (TOF) cameras is proposed in this paper and applied to the Microsoft Kinect V2. Based on the Guide to the Expression of Uncertainty in Measurement (GUM), the uncertainty of a three-dimensional (3D) scene reconstruction is analysed. In particular, the random and the systematic components of the uncertainty are evaluated for the single sensor pixel and for the complete depth camera. The manufacturer declares an uncertainty in the measurement of the central pixel of the sensor of about few millimetres (Kinect for Windows Features, 2015), which is considerably better than the first version of the Microsoft Kinect (Chow et al., 2012 [1]). This work points out that performances are highly influenced by measuring conditions and environmental parameters of the scene; actually the 3D point reconstruction uncertainty can vary from 1.5 to tens of millimetres

Real-Time Description of the Electronic Dynamics for a Molecule close to a Plasmonic Nanoparticle

The optical properties of molecules close to plasmonic nanostructures greatly differ from their isolated molecule counterparts. To theoretically investigate such systems in a Quantum Chemistry perspective, one has to take into account that the plasmonic nanostructure (e.g., a metal nanoparticle - NP) is often too large to be treated atomistically. Therefore, a multiscale description, where the molecule is treated by an ab initio approach and the metal NP by a lower level description, is needed. Here we present an extension of one such multiscale model [Corni, S.; Tomasi, J. {\it J. Chem. Phys.} {\bf 2001}, {\it 114}, 3739] originally inspired by the Polarizable Continuum Model, to a real-time description of the electronic dynamics of the molecule and of the NP. In particular, we adopt a Time-Dependent Configuration Interaction (TD CI) approach for the molecule, the metal NP is described as a continuous dielectric of complex shape characterized by a Drude-Lorentz dielectric function and the molecule- NP electromagnetic coupling is treated by an equation-of-motion (EOM) extension of the quasi-static Boundary Element Method (BEM). The model includes the effects of both the mutual molecule- NP time-dependent polarization and the modification of the probing electromagnetic field due to the plasmonic resonances of the NP. Finally, such an approach is applied to the investigation of the light absorption of a model chromophore, LiCN, in the presence of a metal NP of complex shape.Comment: This is the final peer-reviewed manuscript accepted for publication of an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. Link to the original article: http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b1108

Políticas públicas de Biblioteca Escolar: dos primórdios à atualidade

The Brazilian educational trajectory is marked by intense events which determined the history of education and school library. In order to highlight the trajectory of the school library in national legislation, this article has as main objective to analyze what the main laws and initiatives of the Federal Government explicitly on the issue, highlighting their silences and/or omissions on the school library. As methodological procedures, the study counted with the qualitative research, covering literature review and documentary analysis. The results show that despite being included in some of the main educational laws of the country, the school library is not linked into a deeper discussion about its relevance in training. However, due to the recent promulgation of laws and educational policies, realizes that there is a political action concerned with these organizations. However, it is up to the school community charge for the application of the same, in order to avoid it being postponed in detriments of new interests.A trajetória educacional brasileira é marcada por intensos acontecimentos que determinaram a história da educação e da biblioteca escolar. A fim de destacar a trajetória da biblioteca escolar na legislação nacional, o presente artigo teve como objetivo analisar o que as principais legislações e iniciativas do Governo Federal trazem explicitamente sobre a questão, destacando seus silêncios e/ou omissões sobre a biblioteca escolar. Como procedimentos metodológicos, o estudo contou com a pesquisa de natureza qualitativa, abrangendo revisão bibliográfica e análise documental. Os resultados demonstram que apesar de estar contemplada em algumas das principais legislações educacionais do país, a biblioteca escolar não é relacionada em um debate mais profundo sobre o seu papel na formação. Contudo, à promulgação de recentes legislações e políticas educacionais, revela a existência de uma ação política preocupada com essas organizações. Todavia, compete também a comunidade escolar cobrar a aplicação da mesma, a fim de evitar que seja postergada em detrimentos de novos interesses

Recognition of children on age-different images: Facial morphology and age-stable features

The situation of missing children is one of the most emotional social issues worldwide. The search for and identification of missing children is often hampered, among others, by the fact that the facial morphology of long-term missing children changes as they grow. Nowadays, the wide coverage by surveillance systems potentially provides image material for comparisons with images of missing children that may facilitate identification. The aim of study was to identify whether facial features are stable in time and can be utilized for facial recognition by comparing facial images of children at different ages as well as to test the possible use of moles in recognition. The study was divided into two phases (1) morphological classification of facial features using an Anthropological Atlas; (2) algorithm developed in MATLAB® R2014b for assessing the use of moles as age-stable features. The assessment of facial features by Anthropological Atlases showed high mismatch percentages among observers. On average, the mismatch percentages were lower for features describing shape than for those describing size. The nose tip cleft and the chin dimple showed the best agreement between observers regarding both categorization and stability over time. Using the position of moles as a reference point for recognition of the same person on age-different images seems to be a useful method in terms of objectivity and it can be concluded that moles represent age-stable facial features that may be considered for preliminary recognition

Contribution to Electrical System Inertia of Dual Fuel two-stroke Engines in Isolated Grid: A Case Study

The paper analyzed the dynamic performance of dual two-stroke engines with respect to classical Diesel gensets and the contribution to increase the rotating inertia of an isolated electrical grid with significant penetration of Renewable Energy Sources (RESs). The role of genset capable to provide better inertia and primary frequency regulation is essential for the integration of renewable generation in order to provide frequency stability and better power quality

Techno-economic analysis of innovative solutions for island grids with high renewable solar share

This paper presents a techno-economic analysis of a hybrid dispatch strategy on an island through conventional internal combustion engine (ICE) and innovative gas turbine (GT) with pressure gain combustion (PGC) in the presence of renewable solar-PV. Plant configurations with conventional technologies were defined based on established industrial data, and specifications of novel PGC-GT technology were estimated using the industrial data of conventional GT and on-design results available in the literature. Optimization of the operational strategy was conducted in WECoMP, a modular and flexible software tool developed by Thermochemical Power Group (TPG) at the University of Genova. The performance of different hybrid plants was analyzed in terms of annual production, fuel consumption, curtailment, CO2 emissions, cost, and sensitivity to fuel price. This is complemented by a parallel paper investigating the mechanical rotating inertia features of such prime movers, further supporting their suitability in enabling the integration of non-dispatchable renewables. Results showed that the 2-stroke ICE technology provided the best performance in terms of emissions and cost. Moreover, for all dispatchable prime movers, minimum LCOE occurred at an optimum value of PV capacity that facilitated annual CO2 reduction by 58.6 kton and LCOE reduction by 8.9 €/MWh. Finally, the optimum PV capacity was found to increase with fuel price, signifying the environmental benefits of high fuel prices

A Moving 3D Laser Scanner for Automated Underbridge Inspection

Recent researches have proven that the underbridge geometry can be reconstructed by mounting a 3D laser scanner on a motorized cart travelling on a walkway located under the bridge. The walkway is moved by a truck and the accuracy of the bridge model depends on the accuracy of the trajectory of the scanning head with respect to a fixed reference system. In this paper, we describe a vision-based measurement system that can be used to identify the relative motion of the cart that moves the 3D laser scanner with respect to the walkway. The orientation of the walkway with respect to the bridge is determined using inclinometers and a camera that detect the position of a laser spot, while the position of the truck with respect to the bridge is measured using a conventional odometer. The accuracy of the proposed system was initially evaluated by numerical simulations and successively verified by experiments in laboratory conditions. The complete system has then been tested by comparing the geometry of buildings reconstructed using the proposed system with the geometry obtained with a static scan. Results showed that the error is less than 6 mm; given the satisfying quality of the point clouds obtained, it is also possible to detect small defects on the surface

Incidence and Determinants of Symptomatic and Asymptomatic SARS-CoV-2 Breakthrough Infections After Booster Dose in a Large European Multicentric Cohort of Health Workers-ORCHESTRA Project

Background: SARS-CoV-2 breakthrough infections (BI) after vaccine booster dose are a relevant public health issue. Methods: Multicentric longitudinal cohort study within the ORCHESTRA project, involving 63,516 health workers (HW) from 14 European settings. The study investigated the cumulative incidence of SARS-CoV-2 BI after booster dose and its correlation with age, sex, job title, previous infection, and time since third dose. Results: 13,093 (20.6%) BI were observed. The cumulative incidence of BI was higher in women and in HW aged < 50 years, but nearly halved after 60 years. Nurses experienced the highest BI incidence, and administrative staff experienced the lowest. The BI incidence was higher in immunosuppressed HW (28.6%) vs others (24.9%). When controlling for gender, age, job title and infection before booster, heterologous vaccination reduced BI incidence with respect to the BNT162b2 mRNA vaccine [Odds Ratio (OR) 0.69, 95% CI 0.63-0.76]. Previous infection protected against asymptomatic infection [Relative Risk Ratio (RRR) of recent infection vs no infection 0.53, 95% CI 0.23-1.20] and even more against symptomatic infections [RRR 0.11, 95% CI 0.05-0.25]. Symptomatic infections increased from 70.5% in HW receiving the booster dose since < 64 days to 86.2% when time elapsed was > 130 days. Conclusions: The risk of BI after booster is significantly reduced by previous infection, heterologous vaccination, and older ages. Immunosuppression is relevant for increased BI incidence. Time elapsed from booster affects BI severity, confirming the public health usefulness of booster. Further research should focus on BI trend after 4th dose and its relationship with time variables across the epidemics.BackgroundSARS-CoV-2 breakthrough infections (BI) after vaccine booster dose are a relevant public health issue.MethodsMulticentric longitudinal cohort study within the ORCHESTRA project, involving 63,516 health workers (HW) from 14 European settings. The study investigated the cumulative incidence of SARS-CoV-2 BI after booster dose and its correlation with age, sex, job title, previous infection, and time since third dose.Results13,093 (20.6%) BI were observed. The cumulative incidence of BI was higher in women and in HW aged < 50 years, but nearly halved after 60 years. Nurses experienced the highest BI incidence, and administrative staff experienced the lowest. The BI incidence was higher in immunosuppressed HW (28.6%) vs others (24.9%). When controlling for gender, age, job title and infection before booster, heterologous vaccination reduced BI incidence with respect to the BNT162b2 mRNA vaccine [Odds Ratio (OR) 0.69, 95% CI 0.63-0.76]. Previous infection protected against asymptomatic infection [Relative Risk Ratio (RRR) of recent infection vs no infection 0.53, 95% CI 0.23-1.20] and even more against symptomatic infections [RRR 0.11, 95% CI 0.05-0.25]. Symptomatic infections increased from 70.5% in HW receiving the booster dose since < 64 days to 86.2% when time elapsed was > 130 days.ConclusionsThe risk of BI after booster is significantly reduced by previous infection, heterologous vaccination, and older ages. Immunosuppression is relevant for increased BI incidence. Time elapsed from booster affects BI severity, confirming the public health usefulness of booster. Further research should focus on BI trend after 4th dose and its relationship with time variables across the epidemics