Towards truly simultaneous PIXE and RBS analysis of layered objects in cultural heritage

For a long time, RBS and PIXE techniques have been used in the field of cultural heritage. Although the complementarity of both techniques has long been acknowledged, its full potential has not been yet developed due to the lack of general purpose software tools for analysing the data from both techniques in a coherent way. In this work we provide an example of how the recent addition of PIXE to the set of techniques supported by the DataFurnace code can significantly change this situation. We present a case in which a non homogeneous sample (an oxidized metal from a photographic plate -heliography- made by Niepce in 1827) is analysed using RBS and PIXE in a straightforward and powerful way that can only be performed with a code that treats both techniques simultaneously as a part of one single and coherent analysis. The optimization capabilities of DataFurnace, allowed us to obtain the composition profiles for these samples in a very simple way.Comment: 9 pages, 3 figure

Confronting deep uncertainty in the forest carbon industry

Global momentum on carbon markets has the potential to direct substantial capital toward protecting the world’s forests. Yet the billion-dollar forest-carbon-offsetting industry is attracting criticism, in part from doubts about the methods used to measure and causally attribute changes in tree cover and biomass (1). Many actors in the industry are thus pursuing increasingly detailed measurement and monitoring of carbon outcomes and risks, under the assumption that this will improve accuracy and offset integrity (2). However, mounting scientific evidence (3, 4) implies that many forest landscapes are subject to “deep uncertainty” (5), such that claims of high accuracy in assessing carbon change are likely to remain inherently contestable, regardless of the technology or methodology deployed. Further, demands for such accuracy are likely to perpetuate inefficiencies and injustices among carbon suppliers (6–9). Approaches from other sectors may offer alternative ways forward in the absence of highly accurate measurements of outcomes

Development of a Submillimetric GNSS-Based Distance Meter for Length Metrology

[EN] Absolute distance determination in the open air with an uncertainty of a few tenths of a millimetre is increasingly required in many applications that involve high precision geodetic metrology. No matter the technique used to measure, the resulting distances must be proven consistent with the unit of length (SI-metre) as realized in the outdoor facilities traditionally used in length metrology, which are also known as calibration baselines of reference. The current calibration baselines of reference have distances in the range of 10 to 1000 m, but at present there is no solution on the market to provide distances with submillimetric precision in that range. Consequently, new techniques such as multi-wave interferometry, two-wave laser telemeters or laser trackers are being developed. A possible alternative to those sophisticated and expensive techniques is the use of widely used Global Navigation Satellite Systems (GNSS) in order to provide a GNSS-Based Distance Meter (GBDM). The use of a GBDM as a potential technique for length metrology has been thoroughly analysed in several European research projects by using the state-of-the-art geodetic software, such as Bernese 5.2, but no definite conclusions have been drawn and some metrological questions are considered still open. In this paper, we describe a dedicated approach to build up a submillimetric GBDM able to be applied in the current calibration baselines of reference, as well as possible methods to cope with the multipath error of the GNSS signals which is the major limitation for the practical uptaking of the technique in metrology. The accuracy of the proposed approach has been tested following the length metrology standards in four experiments carried out in the Universitat Politecnica de Valencia (UPV). The results demonstrate that the proposed GBDM can provide an accuracy of a few tenths of a millimetre in the current calibration baselines of referenceThis work was partly performed within the 18SIB01 GeoMetre project of the European Metrology Programme for Innovation and Research (EMPIR). This project has received funding from the EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme. This research was also partly funded by the Spanish Ministry of Education, Culture and Sports (PRX17/00371).García-Asenjo Villamayor, L.; Baselga Moreno, S.; Atkins, C.; Garrigues Talens, P. (2021). Development of a Submillimetric GNSS-Based Distance Meter for Length Metrology. Sensors. 21(4):1-21. https://doi.org/10.3390/s2104114512121

A Review of Interaction Techniques for Immersive Environments

The recent proliferation of immersive technology has led to the rapid adoption of consumer-ready hardware for Augmented Reality (AR) and Virtual Reality (VR). While this increase has resulted in a variety of platforms that can offer a richer interactive experience, the advances in technology bring more variability in display types, interaction sensors and use cases. This provides a spectrum of device-specific interaction possibilities, with each offering a tailor-made solution for delivering immersive experiences to users, but often with an inherent lack of standardisation across devices and applications. To address this, a systematic review and an evaluation of explicit, task-based interaction methods in immersive environments are presented in this paper. A corpus of papers published between 2013 and 2020 is reviewed to thoroughly explore state-of-the-art user studies, which investigate input methods and their implementation for immersive interaction tasks (pointing, selection, translation, rotation, scale, viewport, menu-based and abstract). Focus is given to how input methods have been applied within the spectrum of immersive technology (AR, VR, XR). This is achieved by categorising findings based on display type, input method, study type, use case and task. Results illustrate key trends surrounding the benefits and limitations of each interaction technique and highlight the gaps in current research. The review provides a foundation for understanding the current and future directions for interaction studies in immersive environments, which, at this pivotal point in XR technology adoption, provides routes forward for achieving more valuable, intuitive and natural interactive experiences

Voiceye: A Multimodal Inclusive Development Environment

People with physical impairments who are unable to use traditional input devices (i.e. mouse and keyboard) are often excluded from technical professions (e.g. web development). Alternative input methods such as eye gaze tracking and speech recognition have become more readily available in recent years with both being explored independently to support people with physical impairments in coding activities. This paper describes a novel multimodal application (“Voiceye”) that combines voice input, gaze interaction, and mechanical switches as an alternative approach for writing code. The system was evaluated with non-disabled participants who have coding experience (N=29) to assess the feasibility of the application in writing HTML and CSS code. Results found that Voiceye was perceived positively and enabled successful completion of coding tasks. A follow-up study with disabled participants (N=5) demonstrated that this method of multimodal interaction can support people with physical impairments in writing and editing code

Freehand Grasping: An Analysis of Grasping for Docking Tasks in Virtual Reality

Natural and intuitive interaction in VR as grasping virtual objects, is still a significant challenge and while recent studies have begun to explore interactions that aim to seamlessly create virtual environments that mimic reality as closely as possible, the dexterous versatility of the human grasp poses significant challenges for usable and intuitive interactions. At present the design considerations for creating natural grasping based interactions in VR are usually drawn from the body of historical knowledge presented for real object grasping. While this may be suitable for some applications, recent work has shown that users in VR grasp virtual objects differently than they would grasp real objects. Therefore, these interaction assumptions may not be directly applicable in furthering the natural interface for users of VR, presenting an absence of knowledge on how users intuitively grasp virtual objects. To begin to address this, we present two experiments where participants (N=39) grasped 16 virtual objects categorised by shape in a mixed docking task exploring rotation, placement and target location. We report on a Wizard of Oz methodology and extract grasp types, grasp category and grasp dimension. We further provide insights into virtual object categorisation for assessing interaction patterns and how these could be used for developing natural and intuitive grasp models by parameterizing grasp types found in these experiments. Our results are of value to be taken forward into a framework of recommendations for grasping interactions and thus begin to bridge the gap in understanding natural grasping patters for VR object interactions

Voice Snapping: Inclusive Speech Interaction Techniques for Creative Object Manipulation

Voice input holds significant potential to support people with physical impairments in producing creative visual design outputs, although it is unclear whether well-established interaction methods used for manipulating graphical assets within mainstream creative applications (typically operated via a mouse, keyboard, or touch input) also present benefits for speech interaction. We present three new voice controlled approaches utilizing interface snapping techniques for manipulating a graphical object’s dimensions: NoSnap, UserSnap, and AutoSnap. A user evaluation with people who have physical impairments (N=25) found that each method enabled participants to successfully control a graphical object’s size across a series of design tasks, although the automated snapping approach utilized within AutoSnap was found to be more efficient, accurate, and usable. Subjective feedback from participants also highlighted a strong preference for AutoSnap over the other techniques in terms of efficiency and ease of use

Exposure to gamma tACS in Alzheimer's disease: A randomized, double-blind, sham-controlled, crossover, pilot study.

Objective: To assess whether exposure to non-invasive brain stimulation with transcranial alternating current stimulation at γ frequency (γ-tACS) applied over Pz (an area overlying the medial parietal cortex and the precuneus) can improve memory and modulate cholinergic transmission in mild cognitive impairment due to Alzheimer's disease (MCI-AD). Methods: In this randomized, double-blind, sham controlled, crossover pilot study, participants were assigned to a single 60 min treatment with exposure to γ-tACS over Pz or sham tACS. Each subject underwent a clinical evaluation including assessment of episodic memory pre- and post-γ-tACS or sham stimulation. Indirect measures of cholinergic transmission evaluated using transcranial magnetic stimulation (TMS) pre- and post-γ-tACS or sham tACS were evaluated. Results: Twenty MCI-AD participants completed the study. No tACS-related side effects were observed, and the intervention was well tolerated in all participants. We observed a significant improvement at the Rey auditory verbal learning (RAVL) test total recall (5.7 [95% CI, 4.0 to 7.4], p < 0.001) and long delayed recall scores (1.3 [95% CI, 0.4 to 2.1], p = 0.007) after γ-tACS but not after sham tACS. Face-name associations scores improved during γ−tACS (4.3 [95% CI, 2.8 to 5.8], p < 0.001) but not after sham tACS. Short latency afferent inhibition, an indirect measure of cholinergic transmission evaluated with TMS, increased only after γ-tACS (0.31 [95% CI, 0.24 to 0.38], p < 0.001) but not after sham tACS. Conclusions: exposure to γ-tACS over Pz showed a significant improvement of memory performances, along with restoration of intracortical connectivity measures of cholinergic neurotransmission, compared to sham tACS

UNFOLD Deliverable D5. Establishment of CoPs report

Description of the two implementations carried out in Plone and PHP Nuke by UNFOLD in providing support for three CoP