Groove gap waveguide in metallized 3D-printed plastic and in mechanized aluminium in Ka band

This paper conducts a comparison between two different manufacturing technologies for a prototype in Groove Gap Waveguide. Both technologies are metallized 3D-printed plastic and mechanized aluminium. The prototype is a straight section with transitions to WR-28 that works in the frequency band from 28 to 30 GHz. The main properties of the technologies in terms of losses, weight and ease of manufacture are presented, as well as measurements for both prototypes together with simulations

The Effect of Haptic Feedback on Basic Social. Interaction within Shared Virtual Environments

This paper describes an experiment that studies the effect of basic haptic feedback in creating a sense of social interaction within a shared virtual environment (SVE). Although there have been a number of studies investigating the effect of haptic feedback on collaborative task performance, they do not address the effect it has in inducing social presence. The purpose of this experiment is to show that haptic feedback enhances the sense of social presence within a mediated environment. An experiment was carried out using a shared desktop based virtual environment where 20 remotely located couples who did not know one another had to solve a puzzle together. In 10 groups they had shared haptic communication through their hands, and in another group they did not. Hence the haptic feedback was not used for completing the task itself, but rather as a means of social interacting – communicating with the other participant. The results suggest that basic haptic feedback increases the sense of social presence within the shared VE

TCP-Based distributed offloading architecture for the future of untethered immersive experiences in wireless networks

IMX '22: ACM International Conference on Interactive Media Experiences, 22-24 June 2022, Aveiro, Portugal.Task offloading has become a key term in the field of immersive media technologies: it can enable lighter and cheaper devices while providing them higher remote computational capabilities. In this paper we present our TCP-based offloading architecture. The architecture, has been specifically designed for immersive media offloading tasks with a particular care in reducing any processing overhead which can degrade the network performance. We tested the architecture for different offloading scenarios and conditions on two different wireless networks: WiFi and 5G millimeter wave technologies. Besides, to test the network on alternative millimeter wave configurations, currently not available on the actual 5G millimeter rollouts, we used a 5G Radio Access Network (RAN) real-time emulator. This emulator was also used to test the offloading architecture for an simulated immersive user sharing network resources with other users. We provide insights of the importance of user prioritization techniques for successful immersive media offloading. The results show a great performance for the tested immersive media scenarios, highlighting the relevance of millimeter wave technology for the future of immersive media applications.This work has received funding from the European Union (EU) Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie ETN TeamUp5G, grant agreement No. 813391

Optical Analysis of a Hexagonal 42kWe High-flux Solar Simulator

AbstractA 42-kWe high-flux solar simulator with hexagonal reflector symmetry has been designed, built and optically characterized at IMDEA Energy Institute, Spain. This facility makes possible the lab-scale generation of a quasi-uniform high radiation flux density and high stagnation temperatures and it will be used as a platform for analyzing processes under concentrating solar energy conditions; for instance, central receivers in concentrating solar power plants and solar fuel production process in thermochemical reactors. The high-flux solar simulator consists of seven reflector-lamp pairs arranged in the center and vertices of a regular hexagon. The 6-kWe Xe short arc lamps are allocated in the primary focus of the corresponding truncated ellipsoidal reflector. This hexagonal symmetry provides compactness and quasi-uniform spatial distribution of the radiation at the system common focal plane.This work presents the experimental characterization of the solar simulator optical performance. Preliminary measurements indicate an average flux density at the focal plane of 3.5 MW/m2 that means 3,500 suns (1 sun = 1kW/m2) and stagnation temperature of approximately 2,800K

New antenna topologies for 5G communication systems

This paper presents new antenna topologies for 5G communication systems. The objective is the study of low losses distribution network technologies and the radiating elements for low profile antennas for 5G applications. Different technologies are considered as PCB technology, LTCC technology and metallized 3D printing in terms of design procedures, transmission losses and manufacturing processes in order to contribute to these types of technologies. Different designs and prototypes are done to validate these antennas for 5G communication system

Comparison of 60 GHz Planar Array Antenna on LTCC and Rogers Substrates for 5G applications

The spectrum currently allocated for mobile service is fragmented into different frequency bands (800, 900, 1800, 2100,2600 MHz). However, those bands are getting congested and they are unable to satisfy the increasing user demand. The use of millimeter-wave bands appears as an opportunity to implement short range 5G data networks. The principal advantage of using millimeter-wave bands is the large amount of contiguous spectrum that can be used, which allows the delivery of high data rates. However, the technology is not yet so mature as in microwave frequencies. This paper presents array antennas using different materials: low-temperature cofired ceramics (LTCC) and Rogers substrates of a single radiating element, 1x2 and 2x2 array. The 2x2 array antenna achieves a -10 dB bandwidth from 58 to 65 GHz with a peak gain of 10.8 dBi at 60 GHz

Analysis of documental heritage of CETA in standardization of the Spanish manufacturing automotive industry

El presente trabajo muestra el proceso de recopilación, análisis, revisión y gestión realizada sobre el conjunto de normas CETA (Centro de Estudios Técnicos de Automoción), que constituyeron un interesante proceso de normalización llevado a cabo en el sector industrial relacionado con la fabricación de vehículos automóviles y que es uno de los elementos más desconocidos del patrimonio normalizador español. Asimismo, se ha realizado una evaluación comparativa con la normativa UNE vigente. La normativa analizada presenta una serie de características que la diferencian de la normalización actual. Los resultados muestran la influencia positiva que las normas CETA ejercieron en el desarrollo del propio sector así como la importancia que las mismas tuvieron en la generación de contenidos de actuales normas UNE.Universidad de Málaga – Campus de Excelencia Internacional Andalucía Tec

Students frequently ask: ‘Yes but...What is the utility of physics?’

Two Teaching Innovation Projects were carried out in the framework of the subjects ‘Physics I’ and ‘Physics II’ for different Degrees on Engineering at the Engineering High School of the University of Cadiz, Spain, during the 2013-2014 course. The aim of these Projects was to catch the interest of first course students on physical phenomena and principles, a matter frequently considered as ‘difficult’ or even ‘boring’ for them when it is approached from an excessively formal scope. The methodology of the two Projects was based on experiments of Recreational Physics, different toys and devices, and other resources as posters, books and online contents. The Projects were conducted during Theory, Laboratory, and Online classes of Physics I and II, and their results were evaluated from questionnaires to the students. Main conclusions derived from them were: i) a significant increment on the interest of students on Physics and Science; ii) the aim of students for learning more about this kind of recreational physical experiments; and iii) a general sensation of enjoying the study and analysis of physical phenomena by students –and teachers as well–. In addition, students manifested their interest in this methodology to be applied to other Engineering subjects of their Degrees

Multi-modal ultrasound imaging for breast cancer detection

This work describes preliminary results of a two-modality imaging system aimed at the early detection of breast cancer. The first technique is based on compounding conventional echographic images taken at regular angular intervals around the imaged breast. The other modality obtains tomographic images of propagation velocity using the same circular geometry. For this study, a low-cost prototype has been built. It is based on a pair of opposed 128-element, 3.2 MHz array transducers that are mechanically moved around tissue mimicking phantoms. Compounded images around 360 degrees provide improved resolution, clutter reduction, artifact suppression and reinforce the visualization of internal structures. However, refraction at the skin interface must be corrected for an accurate image compounding process. This is achieved by estimation of the interface geometry followed by computing the internal ray paths. On the other hand, sound velocity tomographic images from time of flight projections have been also obtained. Two reconstruction methods, Filtered Back Projection (FBP) and 2D Ordered Subset Expectation Maximization (2D OSEM), were used as a first attempt towards tomographic reconstruction. These methods yield useable images in short computational times that can be considered as initial estimates in subsequent more complex methods of ultrasound image reconstruction. These images may be effective to differentiate malignant and benign masses and are very promising for breast cancer screening. (C) 2015 The Authors. Published by Elsevier B.V