We are surrounded by a growing number of products with embedded intelligence relying on sensors and internet access. These smart products, that already transform our lives, are also physical entities that need to be manufactured. Manufacturing today similarly relies on data and data-driven insights to improve quality, efficiency, and safety on the shopfloor. This paper discusses the vision to utilize the ability of smart products to sense and communicate already during their own manufacturing to enrich the smart manufacturing system's data for better insights development and optimization. We furthermore, discuss the barriers and opportunities embedded in such a paradigm shift.
The behavior of emerging wireless sensor networks is often characterized by short bursts of computation and communication followed by long periods of inactivity. As the unit devices are typically powered by batteries, conservation of energy - particularly during idle time - is paramount. Subthreshold logic has been proposed for providing lower energy per operation than traditional CMOS, but does so with a significant degradation of performance. This paper describes a novel approach of dynamically switching between sub- and super-threshold operation through the use of floating gate techniques in order to provide high performance during active periods and low leakage during idle periods.
To maximize the sustainability of future space missions, the utilization of local resources available on the Moon or Mars, also known as in-situ resource utilization (ISRU), is crucial to develop infrastructures such as habitation modules, power generation, and energy storage facilities. 1–3 This work presents a perspective aiming to introduce the future of batteries manufacturing on the lunar and martian environment from ISRU materials. Based on the composition of the lunar and martian soil, 4–7 the choice of the battery technology and materials for the different battery components (electrodes, electrolyte, current collectors and packaging) are examined. The motivations for selecting additive manufacturing technologies as a unique approach to support human operations in space, on the surface of the Moon or Mars, and any other locations where cargo resupply is not as readily available, as well as the need for high resolution multi-material printing methods, are discussed. Additive manufacturing paves the way to three-dimensional rechargeable battery architectures with enhanced specific surface area, three-dimensional ion diffusion, and improved power performances, while also allowing the development of shape-conformable batteries to maximize the energy storage within the final application. 8–15 The in-space additive manufacturing process of shape-conformable batteries using in-situ resources is in direct alignment with the NASA’s objectives to demonstrate in-space autonomous manufacturing and assembly of complete systems by 2030, and to enable Humans survival, explore deep space, and visit planetary surfaces by 2040. 16 Such initiatives also contribute to reducing power-related payload weight and volume in future missions, thus reducing the risk for long term Moon or even Mars missions where rapid resupply will be logistically infeasible. In this context, this presentation will provide a perspective of what is required to 3D print batteries on lunar and martian surfaces, 17 an overview of our ongoing project dedicated to AM of sodium-ion batteries from resources available on the Moon and Mars and our recent work on 3D printing of TiO 2 negative electrode material by means of the vat photopolymerization process. 18 (1) Anand, M. et al. A Brief Review of Chemical and Mineralogical Resources on the Moon and Likely Initial in Situ Resource Utilization (ISRU) Applications. Planet. Space Sci. 2012 , 74 (1), 42–48. (2) Edmunson. Building a Sustainable Human Presence on the Moon and Mars. New Horizons Summit . (3) McMillon-Brown, L. et al. What Would It Take to Manufacture Perovskite Solar Cells in Space? ACS Energy Lett. 2022 , 7 (3), 1040–1042. (4) Heiken, G. et al. Lunar Sourcebook: A User’s Guide to the Moon ; CUP Archive, 1991. (5) Dreibus, G. et al. Lithium and Halogens in Lunar Samples. Philos. Trans. R. Soc. Lond. A 1977 , 285 (1327), 49–54. (6) Taylor, G. J. The Bulk Composition of Mars. Geochem. Explor. Environ. Analy. 2013 , 73 (4), 401–420. (7) Yoshizaki, T. et al. The Composition of Mars. Geochim. Cosmochim. Acta 2020 , 273 , 137–162. (8) Maurel, A. et al. Highly Loaded Graphite-Polylactic Acid Composite-Based Filaments for Lithium-Ion Battery Three-Dimensional Printing. Chem. Mater. 2018 , 30 (21), 7484–7493. (9) Maurel, A. et al. Considering Lithium-Ion Battery 3D-Printing via Thermoplastic Material Extrusion and Polymer Powder Bed Fusion. Additive Manufacturing 2020 , 101651. (10) Martinez, A. C. et al. Additive Manufacturing of LiNi 1/3 Mn 1/3 Co 1/3 O 2 Battery Electrode Material via Vat Photopolymerization Precursor Approach. Sci. Rep. 2022 , 12 (1), 1–13. (11) Maurel, A. et al. Overview on Lithium-Ion Battery 3D-Printing By Means of Material Extrusion. ECS Trans. 2020 , 98 (13), 3–21. (12) Maurel, A. et al. Toward High Resolution 3D Printing of Shape-Conformable Batteries via Vat Photopolymerization: Review and Perspective. IEEE Access 2021 , 9 , 140654–140666. (13) Maurel, A. et al. Ag-Coated Cu/Polylactic Acid Composite Filament for Lithium and Sodium-Ion Battery Current Collector Three-Dimensional Printing via Thermoplastic Material Extrusion. Frontiers in Energy Research 2021 , 9 (70). https://doi.org/10.3389/fenrg.2021.651041. (14) Ragones, H. et al. Towards Smart Free Form-Factor 3D Printable Batteries. Sustainable Energy & Fuels 2018 , 2 (7), 1542–1549. (15) Egorov, V. et al. Evolution of 3D Printing Methods and Materials for Electrochemical Energy Storage. Adv. Mater. 2020 , 32 (29). https://doi.org/10.1002/adma.202000556. (16) Murphy, P. STMD’s New Strategic Framework Update, 2017. https://www.nasa.gov/sites/default/files/atoms/files/336429-508-to5_nac_dec_2017_strategicplanningintegration_tagged.pdf. (17) Maurel, A. et al. What Would Battery Manufacturing on the Moon and Mars Look Like? (submitted) . (18) Maurel, A. et al. 3D Printed TiO 2 Negative Electrodes for Sodium-Ion and Lithium-Ion Batteries Using Vat Photopolymerization (submitted) .
Presents a collection of slides covering the following: single-chip NTSC/PAL television; mobile applications; analog television; terrestrial TV; analog TV signaling; TV architecture; direct conversion TV-on-a-chip; NTSC/ PAL receiver; low-noise amplifier; mixer; LO harmonics; harmonic rejection filtering; harmonic rejection mixing; LO generation; VSB Nyquist filtering; and digital TV.
Purpose This study aims to comprehensively investigate the electron beam powder bed fusion (EB-PBF) process for copper, offering validated estimations of melt pool temperature and morphology through numerical and analytical approaches. This work also assesses how process parameters influence the temperature fluctuations and the morphological changes of the melt pool. Design/methodology/approach Two distinct methods, an analytical model and a numerical simulation, were used to assess temperature profiles, melt pool morphology and associated heat transfer mechanisms, including conduction and keyhole mode. The analytical model considers conduction as the dominant heat transfer mechanism; the numerical model also includes convection and radiation, incorporating specific parameters such as beam power, scan speed, thermophysical material properties and powder interactions. Findings Both the analytical model and numerical simulations are highly correlated. Results indicated that the analytical model, emphasising material conduction, exhibited exceptional precision, although at substantially reduced cost. Statistical analysis of numerical outcomes underscored the substantial impact of beam power and scan speed on melt pool morphology and temperature in EB-PBF of copper. Originality/value This numerical simulation of copper in EB-PBF is the first high-fidelity model to consider the interaction between powder and substrate comprehensively. It accurately captures material properties, powder size distribution, thermal dynamics (including heat transfer between powder and substrate), phase changes and fluid dynamics. The model also integrates advanced computational methods such as computational fluid dynamics and discrete element method. The proposed model and simulation offer a valuable predictive tool for melt pool temperature, heat transfer processes and morphology. These insights are critical for ensuring the bonding quality of subsequent layers and, consequently, influencing the overall quality of the printed parts.
The influence of different levels of alkalinity, expressed using M 2 O-to-binder ratio (n) and activator SiO 2 -to-M 2 O ratio (M s ), (M being the Na + or K + cation) on the reaction kinetics, compressive strength development and the reaction product formation in slag-based systems activated using alkali powders are discussed.The fundamental idea is to better understand one-part, "just-add-water" type alkali activated binders that are easy-to-use than the systems that rely on liquid activators.The difference in the behavior of the systems with changes in the cationic species (Na + or K + ) and the overall levels of alkalinity is elucidated.Heat release and its rate, and thermal analysis and Fourier Transform Infrared Spectroscopy (FTIR) are used for the characterization of the reaction and the products formed.The influence of activator alkalinity on the initial dissolution and acceleration phases is examined using isothermal calorimetry.An increase in M s is found to result in reduced early-age and slightly increased later-age compressive strengths.The activator cationic species influences later-age strengths, Recent Progress in Materials 2022; 4(2), doi:10.21926
Summary form only given. Additive manufacturing (AM), often called 3D printing, has received much attention recently with impressive demonstrations ranging from musical instruments, to vehicles, to housing components or even entire buildings. Although it has been argued that 3D printing could be the future of manufacturing, the potential and applicability of these methods for creating functional electronics at RF / microwave frequency remain largely unexplored.
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