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A systematic methodology to assess local economic impacts of ocean renewable energy projects: Application to a tidal energy farm
Get PDFPublisher Copyright: © 2023 The AuthorsOcean renewable energy (ORE) is one of the most important clean sources of energy and a major player towards the EU ambitions of being net zero emission by 2050. However, at present, there are few examples of commercially viable ORE technologies and no large-scale projects currently under implementation. Together with social and environmental analyses, the assessment of economic impacts is one of the key elements to help policy makers build a compelling case to gain local community acceptance and implement ORE projects. This paper presents a systematic methodology to assess local economic impacts of renewable energy projects, including jobs creation and impacts on gross value added and income. By combining the use of Location Quotients – which are indexes informing on local industrial specialisation – with the Input-Output multipliers the method can be used to map the supply-chain potential of a local economy and estimate local impacts compared to global ones. The method has been applied to a tidal project carried out in Orkney, Scotland. The research demonstrates the merit of early economic assessments for understanding the economic benefit of ORE projects, particularly for the local communities in which they are located, and it provides a methodological framework to be tested in other case studies.This section outlines the project “Next Evolution in Materials and Models for Ocean Energy” (NEMMO), an ORE project funded by the HORIZON 2020 program, within which the proposed methodology was developed and tested. NEMMO aimed to advance the state-of-the-art of tidal turbine technology by improving the yield and reliability of tidal turbines. As part of the project, a techno-economic analysis and a socio-economic analysis were carried out to analyse the expected financial viability and economic impacts of a 34.5 MW tidal energy array based on the Atir full-scale prototype [ 21 ]. The Atir device consists of a 45-m steel platform connected to a submerged part where the hydrogenators are fitted. Two 21-m-high counter-rotating three-bladed rotors are situated below the hull, which combined achieve 1.5 MW rated power ( Fig. 2 ). Fig. 3 shows the site location of Fall of Warness, Orkney (UK), the offshore tidal test area of the European Marine Energy Centre (EMEC), where the Atir device has been operating since March 2019.Peer reviewe
Variability debt in opportunistic reuse: A multi-project field study
No full textPublisher Copyright: © 2024 Elsevier Inc.Technical debt is a metaphor to guide the identification, measurement, and general management of decisions that are appropriate in the short term but create obstacles in the future evolution and maintenance of systems. Variability management, which is the ability to create system variants to satisfy different business or technical needs, is a potential source of technical debt. Variability debt, recently characterized in a systematic literature review we conducted, is caused by suboptimal solutions in the implementation of variability management in software systems. In this work, we present a field study in which we report quantitative and qualitative analysis of variability debt through artifact analysis (e.g., requirements, source code, and tests) and a survey with stakeholders (e.g., analysts, developers, managers, and a user). The context is a large company with three different systems, where opportunistic reuse (a.k.a., copy-and-paste or clone-and-own reuse) of almost all project artifacts was performed to create variants for each system. We analyze the variability debt phenomenon related to opportunistic reuse, and we assess the validity of the metaphor to create awareness to stakeholders and guide technical debt management research related to variability aspects. The results of the field study show evidences of factors that complicate the evolution of the variants, such as code duplication and non-synchronized artifacts. Time pressure is identified as the main cause for not considering other options than opportunistic reuse. Technical practitioners mostly agree on the creation of usability problems and complex maintenance of multiple independent variants. However, this is not fully perceived by managerial practitioners.Peer reviewe
Lateral Evasive Maneuver with Shared Control Algorithm: A Simulator Study
Get PDFPublisher Copyright: © 2024 by the authors.Shared control algorithms have emerged as a promising approach for enabling real-time driver automated system cooperation in automated vehicles. These algorithms allow human drivers to actively participate in the driving process while receiving continuous assistance from the automated system in specific scenarios. However, despite the theoretical benefits being analyzed in various works, further demonstrations of the effectiveness and user acceptance of these approaches in real-world scenarios are required due to the involvement of the human driver in the control loop. Given this perspective, this paper presents and analyzes the results of a simulator-based study conducted to evaluate a shared control algorithm for a critical lateral maneuver. The maneuver involves the automated system helping to avoid an oncoming motorcycle that enters the vehicle’s lane. The study’s goal is to assess the algorithm’s performance, safety, and user acceptance within this specific scenario. For this purpose, objective measures, such as collision avoidance and lane departure prevention, as well as subjective measures related to the driver’s sense of safety and comfort are studied. In addition, three levels of assistance (gentle, intermediate, and aggressive) are tested in two driver state conditions (focused and distracted). The findings have important implications for the development and execution of shared control algorithms, paving the way for their incorporation into actual vehicles.Peer reviewe
An overactuated aerial robot based on cooperative quadrotors attached through passive universal joints: Modeling, control and 6-DoF trajectory tracking
Get PDFPublisher Copyright: © 2024 The Author(s)This article discusses a novel aerial robot architecture that overcomes the underactuation of conventional multirotor systems without adding dedicated rotor tilting actuators. The proposed system is based on four quadrotors cooperatively carrying a central body to which they are attached through passive universal joints. While conventional parallel axis multirotors are underactuated, the proposed mechanism makes the system overactuated, enabling independent position and orientation control of the main body. This implies that the payload can be carried in the minimum drag orientation, it enables take-off and landing on inclined surfaces and it provides thrust-vectoring capabilities to the system, leading to high control authority. A detailed dynamic model is derived making use of Lagrangian formalism and a hierarchical control law based on such model is proposed to stabilize the system. This control law is designed to ensure good tracking while minimizing power consumption. The proposed control law and the capabilities of the architecture are evaluated in simulation and in outdoor experimental flights, where the aerial robot shows autonomous tracking of the six degrees of freedom (DoF) of the main body, an inherently unfeasible maneuver for conventional underactuated multirotors.Peer reviewe
Deep learning-based instance segmentation for improved pepper phenotyping
Get PDFPublisher Copyright: © 2024 The Author(s)Vegetable breeding companies invest a considerable amount of their resources in phenotyping. The advancement of computer vision technology has made it possible to digitalize these processes, leading to improved efficiency and quality. However, phenotyping activities often take place in outdoor fields or greenhouses, where the environmental/illumination conditions are constantly changing. This lack of standardization presents a problem for automatically isolating the relevant elements in the images, which is an important first step for phenotyping. Classical image analysis methods have shown not to be robust enough for that in these changing conditions. However, in the last years, deep learning models have demonstrated to be able to identify and learn meaningful features that are more robust and representative of the underlying patterns, enabling them to handle diverse and changeable conditions effectively. In this work, we propose a pepper instance segmentation solution based on deep learning after harvest under field conditions. We implement the method and validate it for three pepper varieties: Blocky Bell, Jalapeño and Lamuyo. We compare the performance of this new method for each variety with a previous solution based on classical image processing techniques, with the objective of measuring and demonstrating the superiority of deep learning-based instance segmentation over traditional methods as a first step for phenotyping. The instance segmentation deep learning based models outperform the results obtained by classical image processing algorithms for the three pepper varieties: in Blocky Bell mAP is increased from 0.63 to 0.97, in Jalapeño from 0.39 to 0.52 and in Lamuyo from 0.67 to 0.97.Peer reviewe
A Quantum Computing-Based System for Portfolio Optimization Using Future Asset Values and Automatic Reduction of the Investment Universe
No full textPublisher Copyright: © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.One of the problems in quantitative finance that has received the most attention is the portfolio optimization problem. Regarding its solving, this problem has been approached using different techniques, with those related to quantum computing being especially prolific in recent years. In this study, we present a system called Quantum Computing-based System for Portfolio Optimization with Future Asset Values and Automatic Universe Reduction (Q4FuturePOP), which deals with the Portfolio Optimization Problem considering the following innovations: (i) the developed tool is modeled for working with future prediction of assets, instead of historical values; and (ii) Q4FuturePOP includes an automatic universe reduction module, which is conceived to intelligently reduce the complexity of the problem. We also introduce a brief discussion about the preliminary performance of the different modules that compose the prototypical version of Q4FuturePOP.Peer reviewe
Biocompatible adipose extracellular matrix and reduced graphene oxide nanocomposite for tissue engineering applications
Get PDFPublisher Copyright: © 2024 The AuthorsDespite the immense need for effective treatment of spinal cord injury (SCI), no successful repair strategy has yet been clinically implemented. Multifunctional biomaterials, based on porcine adipose tissue-derived extracellular matrix (adECM) and reduced graphene oxide (rGO), were recently shown to stimulate in vitro neural stem cell growth and differentiation. Nevertheless, their functional performance in clinically more relevant in vivo conditions remains largely unknown. Before clinical application of these adECM-rGO nanocomposites can be considered, a rigorous assessment of the cytotoxicity and biocompatibility of these biomaterials is required. For instance, xenogeneic adECM scaffolds could still harbour potential immunogenicity following decellularization. In addition, the toxicity of rGO has been studied before, yet often in experimental settings that do not bear relevance to regenerative medicine. Therefore, the present study aimed to assess both the in vitro as well as in vivo safety of adECM and adECM-rGO scaffolds. First, pulmonary, renal and hepato-cytotoxicity as well as macrophage polarization studies showed that scaffolds were benign in vitro. Then, a laminectomy was performed at the 10th thoracic vertebra, and scaffolds were implanted directly contacting the spinal cord. For a total duration of 6 weeks, animal welfare was not negatively affected. Histological analysis demonstrated the degradation of adECM scaffolds and subsequent tissue remodeling. Graphene-based scaffolds showed a very limited fibrous encapsulation, while rGO sheets were engulfed by foreign body giant cells. Furthermore, all scaffolds were infiltrated by macrophages, which were largely polarized towards a pro-regenerative phenotype. Lastly, organ-specific histopathology and biochemical analysis of blood did not reveal any adverse effects. In summary, both adECM and adECM-rGO implants were biocompatible upon laminectomy while establishing a pro-regenerative microenvironment, which justifies further research on their therapeutic potential for treatment of SCI.Peer reviewe
Modelling and Control Solution of an E-axle for Third-Generation Electric Vehicles
No full textPublisher Copyright: © 2024, The Author(s), under exclusive license to Springer Nature Switzerland AG.This work studies the use of an e-axle based on a six-phase IPMSM. In addition, it has a dc bus with a cascade configuration. Moreover, a dc/dc converter is incorporated between the battery module and the six-phase inverter to provide the vehicle with fast charging capabilities, while avoiding the use of power semiconductors with high nominal voltages. In this scenario, the control algorithm must cope with the non-linearities of the machine by providing an accurate setpoint command for the entire torque and speed range of the inverter. Therefore, cross-coupling effects between the windings must be considered, and the voltage of the cascade link capacitors must be actively controlled and balanced. Given this, the authors propose a novel control approach that provides all these functionalities. The proposal has been experimentally validated on a full-scale prototype 70 kW electric drive, tested in a laboratory and an electric vehicle under real driving conditions.This chapter was based on work conducted in the EU H2020 project FITGEN, (Grant agreement 824335).Peer reviewe
Novel sensorized additive manufacturing-based enlighted tooling concepts for aeronautical parts
Get PDFPublisher Copyright: © The Author(s) 2024.This paper presents lightweight tooling concepts based on additive manufacturing, with the aim of developing advanced tooling systems as well as installing sensors for real-time monitoring and control during the anchoring and manufacturing of aeronautical parts. Leveraging additive manufacturing techniques in the production of tooling yields benefits in manufacturing flexibility and material usage. These concepts transform traditional tooling systems into active, intelligent tools, improving the manufacturing process and part quality. Integrated sensors measure variables such as displacement, humidity and temperature allowing data analysis and correlation with process quality variables such as accuracy errors, tolerances achieved and surface finish. In addition to sensor integration, additive manufacturing by directed energy arc and wire deposition (DED-arc) has been selected for part manufacturing. The research includes the mechanical characterisation of the material and the microstructure of the material once manufactured by DED-arc. Design for additive manufacturing" principles guide the design process to effectively exploit the capabilities of DED-arc. These turrets, equipped with sensors, allow real-time monitoring and control of turret deformation during clamping and manufacturing of aeronautical parts. As a first step, deformation monitoring is carried out within the defined tolerance of ± 0.15, which allows a control point to be established in the turret. Future analysis of the sensor data will allow correlations with process quality variables to be established. Remarkably, the optimised version of the turret after applying DED technology weighed only 2.2 kg, significantly lighter than the original 6 kg version. Additive manufacturing and the use of lightweight structures for fixture fabrication, followed by the addition of sensors, provide valuable information and control, improving process efficiency and part quality. This research contributes to the development of intelligent and efficient tool systems for aeronautical applications.Peer reviewe
Advanced manufacturing concept of a bio-inspired reaction wheel rotor for small- and medium-sized constellation satellites
No full textPublisher Copyright: © 2023, The Author(s).The increasing number of constellation satellites requires re-thinking of the design and manufacturing process for reaction wheel rotors. Mass optimisation of reaction wheel rotors leads to cost reduction and performance increase. Those optimisations can be realised by taking ideas from nature. Therefore, design principles of diatoms were screened, abstracted and implemented in an algorithm-based design process. In this way, a bio-inspired rotor was created, which considers launch and in-operation loads, is capable of up to 7500 RPM and shows a compact design with a diameter of 282mm. Regarding mechanical performance, an energy density of 4661Jkg-1 and a mass moment of inertia ratio of 0.7584, which considers the component and an idealized design, could be achieved. Compared to a commercial rotor, this is equivalent to a similar inertia ratio and +85 % energy density, but +44 % mass due to manufacturing restrictions. Based on different boundary conditions, different first natural frequency for launch and operation conditions were obtained (658Hz and 210Hz). The new design was cast from nano-reinforced aluminium alloy (AlSi10Mg + Al2O3) in 3D-printed sand moulds that were produced via binder-jetting process. Thus, a hybrid manufacturing process was used, by combining additive manufacturing and casting. Post-processing of the cast part via turning and milling was performed to compensate distortion and achieve the required surface quality. Preliminary vibration measurements were performed, showing a large need for balancing to achieve low vibration emissions.Open Access funding enabled and organized by Projekt DEAL. The LOBSTER use case, as part of the OASIS project, has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 814581 (related to the OASIS project participants AWI, TEC, UoP, CEA, SIS and BLU). The assessment of ZARM Technik AG and the University Bremen is part of Project RIMoNA (Reaction wheel rotor with Integrated MagNetic bearing using Additive manufacturing) which has been funded by ESA Contract 4000124501/18/NL/MH/mg. The authors also acknowledge the support from their direct project partners of the OASIS project, the University of Patras (UoP), BLUMORPHO (BLU), SISTEPLANT (SIS) and the Commissariat à l’énergie atomique et aux énergies alternatives (CEA), and would like to thank them for a good and fruitful collaboration during the development, evaluation and simulation of the proposed proof of concept. Additionally the authors would like to thank ZARM Technik AG and the University Bremen for providing the use case and support during LOBSTER.Peer reviewe