CO2 emissions and global value chains indicators: new evidence for 1995–2018

Globalization and the configuration of production processes around Global Value Chains (GVCs) have become key factors for explaining the recent evolution of environmental and economic indicators. Indeed, previous research found evidence on the significant impact of GVCs indicators (participation and position) on CO2 emissions. Additionally, results obtained in previous literature vary depending on the time period and geographical areas considered. In this context, the main aims of this paper are to analyze the role the GVCs in explaining the evolution of CO2 emissions, and to identify possible structural breaks. This study uses the Multiregional Input-Output framework to calculate a position indicator and two different measures of participation in GVCs (interpreted either as trade openness or international competitiveness). The analysis useS Inter-Country Input-Output tables (ICIO) as main database, which includes 66 countries and 45 industries and covers the period 1995–2018. It is first concluded that upstream positions in GVCs are associated to lower global emissions. Additionally, the effect of participation depends on the measure used: trade openness is linked to lower emissions, while a higher competitiveness in international trade leads to higher emissions. Finally, two structural breaks are identified in 2002 and 2008, revealing that position is significant in the two first subperiods, while participation becomes significant from 2002 onwards. Thus, policies to mitigate CO2 emissions might to be different before and after 2008: currently, reductions in emissions can be achieved by increasing value-added embodied in trade while decreasing the volume of transactions

Applied computer vision for composite material manufacturing by optimizing the impregnation velocity: An experimental approach

T1 Q2 (15/50 Engineering, Manufacturing, IF 2022 = 6.2)The application of the cutting edge industrial solutions in composite manufacturing are optimizing the processes, quality control and resources usage. Computer vision is currently used in many quality control stages, although its potential advantages have not been applied in the process control. In this paper, computer vision is used to control the impregnation velocity in VARI (Vacuum Assisted Resin Infusion) process. As it is known, there is a relationship between the impregnation velocity and the final mechanical properties in LCM (Liquid Composite Manufacturing) processes. Constant and optimum flow front velocity mean optimum mechanical properties, although the nature of the process makes it difficult to keep these conditions. Then, a methodology has been proposed to identify and use the optimum velocity during the manufacturing process. Firstly, the flow front recognition algorithm was calibrated to be used in different reinforcement and fluid systems. Then, tensile and impact specimens have been manufactured and tested at different controlled and uncontrolled velocities. As a result, the tensile modulus has been increased up to 12.6%, as the tensile strength has increased up to 8.7%. Similarly, the maximum reaction force during the impact test has been increased up to 6.5%, as the damaged area has been reduced by 8.8%. For stitched laminates, force results increase up to 3.2%, as the damaged area has been reduced up to 31% when the optimum velocity is used. The experimental results have demonstrated the advantage of using mechanisms to control the impregnation process to achieve improved mechanical properties of composite materials.Airbus Defence and Space S.A.U

The mechanical effect of monitoring and controlling the impregnation in the resin infusion process

T1 Q1 (13/86 Polymer Science, IF 2022 = 5.2)Nowadays, most of industries are optimizing their processes to make their products more competitive. In the composites manufacturing industry, there is a big gap between the almost fully automated processes and those which require an intensive labor-work. Although it has many advantages, the resin infusion process is characterized for its lack of automation. As a consequence, the results are strongly dependent on the process boundaries, the operator skills and expertise, and the result is usually far away from the optimum. In this work, the application of a novel methodology and its capability to maximize the mechanical properties of infusion-manufactured composite materials is presented. After manufacturing stitched and unstitched materials at different impregnation velocities, an optimum value was assessed. The application of this value during the manufacture has increased the tensile and impact properties.Airbus Defense and Space; Leibniz Institute for Composite Material

Enhanced Low-Velocity Impact Properties for Resin Film Infusion-Manufactured Composites by Flow-Control Approach

T1 Q1 (16/90 Polymer Science, IF 2021 = 4.967)The optimization of the mechanical properties of composite materials has been a challenge since these materials were first used, especially in aeronautics. Reduced energy consumption, safety and reliability are mandatory to achieve a sustainable use of composite materials. The mechanical properties of composites are closely related to the amount of defects in the materials. Voids are known as one of the most important defect sources in resin film infusion (RFI)-manufactured composites. Minimizing the defect content leads to maximized mechanical properties and lightweight design. In this paper, a novel methodology based on computer vision is applied to control the impregnation velocity, reduce the void content and enhance the impact properties. Optimized drop-impact properties were found once the impregnation velocity was analyzed and optimized. Its application in both conventional and stitching-reinforced composites concludes with an improvement in the damage threshold load, peak force and damaged area. Although stitching tends to generate additional voids and reduces in-plane properties, the reduction in the damaged area means a positive balance in the mechanical properties. At the same time, the novel methodology provides the RFI process with a noticeable level of automation and control. Consequently, the industrial interest and the range of applications of this process are enhancedAirbus Defence and Space, Leibniz Institut für Verbundwerkstoffe Gmb

A semiempirical error estimation technique for PWV derived from atmospheric radiosonde data

Water vapour is the main responsible for the atmospheric extinction in astronomical observations in different bands. One of the most common and accurate techniques to measure it are the radiosoundings. A method to estimate the error and the optimum number of sampled levels is proposed, considering the uncertainties and the leakage in sampling, based on data from Roque de los Muchachos Observ. and Guimar (Canary Is., Spain), Lindenberg (Germany) and Ny-Ålesund (Norway). The median error is 2.0  %

Indentation Measurement in Thin Plates under Bending Using 3D Digital Image Correlation

T2 Q2 (39/92 Engineering, Multidisciplinary, IF = 2.838)In the current paper, a novel experimental methodology to characterize the contact behavior on thin plates under bending is presented. The method is based on the experimental measurement of the indentation observed during contact experiments. Tests were conducted using aluminum thin plates and a steel sphere to evaluate the effect of thickness and bending during contact. For this purpose, a non-contact optical technique, 3D Digital Image Correlation (3D-DIC), has been employed to measure the out-of-plane displacements experienced at the rear face of the specimens (opposite where the contact is occurring). An indirect measurement of the experimental contact law is obtained for different plate thicknesses (2 mm, 3 mm, 4 mm, 5 mm and 6 mm) as the contact load increases. An energy balance performed during contact experiments made it possible to evaluate and quantify the applied energy to generate bending and contact deformation. When the specimen thickness increases from 2 mm to 6 mm, contact deformation reaches higher values from the total applied energy. In addition, it is also possible to evaluate the portion of the elastically recovered energy for contact and bending deformation during the unloading. It has been observed that thicker specimens show a lower elastic energy recovery due to bending and a higher elastic energy recovery due to contact. Results clearly show how the ratio between absorbed and applied energy changes as the specimen thickness increases, highlighting the relevance of the proposed method for the characterization of contact behavior in thin plates.Corporación Tecnológica de Andalucía, IDEA Agency, Airbus Militar

Flare-like Variability of the Mg~II λ\lambda2798 \AA\ Emission Line and UV Fe~II band in the Blazar CTA~102

We report on the detection of a statistically significant flare-like event in the Mg~II~$\lambda$ 2798~\AA\ emission line and the UV~Fe~II band of CTA~102 during the outburst of autumn 2017. The ratio between the maximum and minimum of $\lambda$3000~\AA\ continuum flux for the observation period ($2010-2017$) is 179$\pm$15. Respectively, the max/min ratios 8.1$\pm$10.5 and 34.0$\pm$45.5 confirmed the variability of the Mg~II emission line and of the Fe~II band. The highest levels of emission lines fluxes recorded coincide with a superluminal jet component traversing through a stationary component located at $\sim$0.1 mas from the 43 GHz core. Additionally, comparing the Mg~II line profile in the minimum of activity against the one in the maximum, we found that the latter is broader and blue-shifted. As a result of these findings, we can conclude that the non-thermal continuum emission produced by material in the jet moving at relativistic speeds is related to the broad emission line fluctuations. In consequence, these fluctuations are also linked to the presence of broad-line region (BLR) clouds located at $\sim$25 pc from the central engine, outside from the inner parsec, where the canonical BLR is located. Our results suggest that during strong activity in CTA~102, the source of non-thermal emission and broad-line clouds outside the inner parsec introduces uncertainties in the estimates of black hole (BH) mass. Therefore, it is important to estimate the BH mass, using single-epoch or reverberation mapping techniques, only with spectra where the continuum luminosity is dominated by the accretion disk.Comment: 15 pages, 6 figures, 2 tables, accepted for publication in Ap

Zeolite based microconcentrators for volatile organic compounds sensing at trace-level: fabrication and performance

A novel 6-step microfabrication process is proposed in this work to prepare microfluidic devices with integrated zeolite layers. In particular, microfabricated preconcentrators designed for volatile organic compounds (VOC) sensing applications are fully described. The main novelty of this work is the integration of the pure siliceous MFI type zeolite (silicalite-1) polycrystalline layer, i.e. 4.0¿¿±¿¿0.5 µm thick, as active phase, within the microfabrication process just before the anodic bonding step. Following this new procedure, Si microdevices with an excellent distribution of the adsorbent material, integrated resistive heaters and Pyrex caps have been obtained. Firstly, the microconcentrator performance has been assessed by means of the normal hexane breakthrough curves as a function of sampling and desorption flowrates, temperature and micropreconcentrator design. In a step further, the best preconcentrator device has been tested in combination with downstream Si based microcantilevers deployed as VOC detectors. Thus, a preliminar evaluation of the improvement on detection sensitivity by silicalite-1 based microconcentrators is presented

The best skies for astronomy

Seminario impartido por Casiana Muñoz-Tuñón (IAC) el 15 de noviembre de 2016 en las Oficinas del CIAI en Santa Cruz de Tenerife