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This article frames the central role played by mission-oriented public procurement in the Brazilian aerospace industry. The difficulties in mastering and promoting the evolution of several disciplines at the firm level, with a relative scarcity of funds for an R&D-intensive industry and an incomplete national innovation system represent merely a fraction of the threat faced by those dealing with Complex Products and Systems. The culture of financing flagship projects using public procurement narrows the potential solutions for complex problems, imposes time constraints to mature critical technologies and exposes these endeavours to high levels of risk. By taking the Dynamic Capabilities as a theoretical framework and Technological Readiness Level as a yardstick to the decision-making process, we have developed a construct to explore two in-depth cases. A cultural shift is required, aiming at providing the means to the progressive maturation of critical technologies using public procurement for innovation. [ABSTRACT FROM AUTHOR]

The electrolysis of water is a crucial technology for extraterrestrial in situ resource utilization in the aerospace sector. Scientific research with unique university characteristics plays a vital role in fostering talent development. Adhering to the principle of integrating science and education, this study combines aerospace-focused scientific research with undergraduate teaching to design a research-oriented experimental course. The approach involves using a two-step method of hydrothermal oxidation and high-temperature phosphidation to fabricate nickel foam self-supported bimetallic phosphide electrodes with ultra-hydrophilic and super-hydrophobic surfaces suitable for the microgravity environment of aerospace space. The performance of hydrogen production from electrolyzed water is investigated. Additionally, relevant thermodynamic concepts from undergraduate physical chemistry courses are incorporated to engage students actively, encourage independent exploration, facilitate the construction of knowledge on extraterrestrial water electrolysis, and uphold the spirit of aerospace patriotism. [ABSTRACT FROM AUTHOR]

Direct digital manufacturing (DDM) is the technology that provides the possibility of producing the final product directly from the 3D CAD model without the aid of any additional tools. Additive manufacturing is the main element of DDM for producing end-user products. The layer-on-layer creation of the product using additive manufacturing provides a lot of design freedom. The layer-on-layer production methodology enables the possibility of producing products with complex and freeform geometries. The layer-on-layer technology allows the material deposition only on the required spots, and hence a significant weight reduction is obtained during the manufacturing of products. Complex geometrical structures with light weight are the greatest interest of the aerospace, spacecraft, and automobile industries. Therefore, these industries have completely relied on novel lightweight materials for producing lightweight structures until now. However, novel lightweight materials are highly expensive and increase the cost of the products significantly. Recent studies show that additive manufacturing helps in producing lightweight structures with high structural stability without the need for expensive lightweight materials. The complete redesign of aircraft, spacecraft, and automobiles suitable for additive manufacturing increases the possibility of producing lightweight structures with high structural stability. The generative design method created for additive manufacturing opens up enormous design possibilities, but the complete redesign of the aircraft or spacecraft would take a few decades. Until then, redesigning and replacing some aerospace components are the most efficient way to achieve the goals in a certain percentage. This study aims to explore the possibilities of implementing DDM for small and medium manufacturing firms by combining the advances of computer application software, topology optimization, and additive manufacturing. The main classifications of aerospace components are static and dynamic. [ABSTRACT FROM AUTHOR]

ABSTRACT The coefficient of friction of low carbon chromium alloy steel with military grade lubricant was high, resulting in increased heat generation and temperature rise of the lubricant in the aircraft power transmission units such as engine gearbox, accessory gearbox and so on. To address this, the current research proposes the addition of TiO2 nanoparticles to MIL grade lubricant as an additive to enhance the tribological performance. In this experimental study, TiO2 nanolubricant was prepared using various surfactants for better suspension of TiO2 nanoparticles, and properties were evaluated for both base lubricant and nanolubricant. The tribological experiments were conducted using a four ball tester, a shear stability tester and a reichert tester. In a four ball test, TiO2 nanolubricant resulted in a 27.3% reduction in wear scar diameter by the addition of TiO2 nanoparticles to the base lubricant. In a shear stability test, TiO2 nanolubricant showed 80% better shear stability than the base lubricant. In the reichert test, the coefficient of friction was reduced by 13% with the TiO2 nanolubricant. The experimental findings demonstrated that the TiO2 nanoparticles, as an additive to a military grade lubricant, have superior tribological properties for aerospace applications. [ABSTRACT FROM AUTHOR]

This study delves into the manufacturing strategies employed for fabricating tensile samples utilized in the mechanical characterization of material extrusion (MEX) components constructed with polyaryletherketone (PAEK) for aerospace applications. Two distinct methods were investigated for obtaining tensile test samples: direct cutting and extraction from a box. These methods were examined under both as-printed and annealing conditions. Quasistatic tensile tests were conducted along the building direction to evaluate the impact of processing conditions on the adhesion of overlying layers. The results unveiled significant disparities in mechanical behavior and crystallinity between directly printed samples and those derived from the box. The Young's modulus exhibited marginal influence; however, the tensile strength of directly printed samples measured at 30 MPa (prior to annealing), corresponding to 50% of the strength observed in samples cut from the box (60 MPa). Moreover, the elongation at rupture of directly printed samples was found to be less than 2%, while that of cut samples exceeded 8%. Notably, directly printed samples exhibited a significant degree of incipient crystallization (12.18%), contrasting with the lower level of crystallinity observed in samples cut from the box (3.27%). These findings underscore the importance of recognizing the limitations associated with direct sample printing, emphasizing its crucial role in accurately characterizing components destined for the aerospace industry. Furthermore, this understanding is pivotal for optimizing the performance and reliability of MEX-printed PAEK components in aerospace engineering applications. [ABSTRACT FROM AUTHOR]

Self-healing composites are smart materials that can self-detect and prevent micro crack propagation and any catastrophic failure in the composite structure. In this study, dicyclopentadiene (DCPD) monomer was encapsulated with urea formaldehyde (UF) by in situ polymerization. These microcapsules were mixed with epoxy, chopped carbon fiber (CF), and multi-walled carbon nanotubes (CNT) to make self-healing composite. Both microcapsules and the composite specimens were extensively tested for their physical, thermal, and mechanical properties. The average diameter and shell thickness of the microcapsules were 268 µm and 805 nm, respectively. DMA analysis suggested that the microcapsules have a glass transition temperature (Tg) of 85°C. FTIR analysis confirmed the presence of CF, multi-walled carbon nanotubes (MWCNT), and other constituents in the composite. The tensile strength of the self-healing composites was tested as per ASTM standards. The incorporation of MWCNT in the composites has significantly improved the tensile strength of the composite without compromising on the self-healing efficiency (90%) compared the unmodified samples (72%). The encouraging results of higher glass transition temperature (85°C) combined with an improved healing efficiency (90%), can be considered as the novelties of this work. As the test results of microcapsules and composite specimens were encouraging, they can find applications in making composite structures for aerospace, windmills, and marine applications. The experimental observations and test results are discussed in detail. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) foam has a high flammability and is widely used in aircraft interiors, presenting a significant danger to occupants. This study analysed three composite intumescent flame-retardant (IFR) coatings for flexible PU foam; expandable graphite (EG), ammonium polyphosphate (APP) and alginate (AG). The coatings were prepared in concentrations of 5 wt%, 10 wt%, and 50 wt% with an acrylic binder. The coated samples were characterised using cone calorimetry, SEM, and mechanical testing. The findings showed peak heat release rate, total heat release, and carbon dioxide production from the 10 wt% triple-layer coating (EG:APP:AG) was 52%, 32%, and 58% less than the PU control. The char of the 10 wt% triple-layer sample effectively suppressed smoke release and inhibited the transfer of fuel and gas volatiles. Mechanical testing demonstrated a 3.4 times increase in tensile strength and a 15.4 times increase in compressive strength (50% compression) compared to the control PU with the 10 wt% triple-layer coating. A fire dynamics simulator model was developed that demonstrated large-scale flammability modelling for commercial aircraft. Future work can explore the integration of IFR coatings into computational analysis. These new bio-based coatings produced promising results for aircraft fire safety and flammability performance for PU polymers. [ABSTRACT FROM AUTHOR]

The rate of rocket launches is accelerating, driven by the rapid global development of the space industry. Rocket launches emit gases and particulates into the stratosphere, where they impact the ozone layer via radiative and chemical processes. We create a three‐dimensional per‐vehicle inventory of stratospheric emissions, accounting for flight profiles and all major fuel types in active use (solid, kerosene, cryogenic and hypergolic). In 2019, stratospheric (15–50 km) rocket launch emissions were 5.82 Gg CO2 ${\mathrm{C}\mathrm{O}}_{2}$, 6.38 Gg H2 ${\mathrm{H}}_{2}$O, 0.28 Gg black carbon, 0.22 Gg nitrogen oxides, 0.50 Gg reactive chlorine and 0.91 Gg particulate alumina. The geographic locations of launch sites are preserved in the inventory, which covers all active launch sites in 2019. We also report the emissions data from contemporary vehicles that were not launched in 2019, so that users have freedom to construct their own launch activity scenarios. A subset of the inventory—stratospheric emissions for successful launches in 2019—is freely available and formatted for direct use in global chemistry‐climate or Earth system models. Plain Language Summary: Many governments and companies have expressed bold ambitions to grow their presence in space. However, rocket launches throw out a stream of air pollutants from their burnt fuel as they pass through the stratosphere, which is where the protective ozone layer resides. Currently, launch operators do not have to measure the impacts of their activities on the ozone layer. We gather together all the publicly available information on rocket launches in 2019, from 18 active spaceports worldwide, and make some careful assumptions to convert each rocket's fuel to its burnt fuel products left in the atmosphere. We encourage modeling groups to use our inventory for studies on how rocket launches may impact the ozone layer. Key Points: We compile a comprehensive emissions inventory of all rocket launches in 2019 at 18 active spaceportsIt itemizes chemically and radiatively active species that are produced by the main rocket fuels (kerosene, cryogenic, solid and hypergolic)We discuss the inventory's uncertainties and its usage in global models to study the impacts of rocket launches on the ozone layer [ABSTRACT FROM AUTHOR]

The aerospace industry and technology are always considered one of the country’s most important and valuable industries. The research area of "Aerospace" is among the priorities of the grand science and technology development strategies, and addressing it is strategically vital. The present research aims to estimate and predict the appropriate algorithm for identifying high-quality aerospace researchers based on Advanced Ensemble Classifier Techniques (AECT) in data mining on the outputs of scientometric analyses and predicting the most essential scientometric-related metrics to identify high-quality researchers. The present study was performed using the protocols of applied research and multiple methods. The studied population includes all aerospace researchers (1945 and 2021) indexed in "The Web of Science Core Collection (WOSCC)". DataLab software and multiple programming languages have been applied in this research. All three algorithms have an accuracy of 0.96 and an F1-score of 0.97, which indicates that the models have high accuracy, validity, sensitivity, and predictive power. The "Blending" algorithm is considered a suitable and predictive model. The output of the LightGBM algorithm is that the most important and robust metric in the evaluation of prominent researchers is a metric from the researchers' effectiveness dimension, the Q parameter. According to the knowledge obtained from the ability to predict AECT in the prediction of highquality researchers, it is possible to use the metrics mentioned in the evaluation of researchers in the field of scientometrics for more accurate and comprehensive prediction. An algorithm that can lead to the optimal and efficient classification of researchers provides the possibility of in-depth analysis of the available data about researchers and smooths the predictive power of the most high-quality researcher. The use of the proposed algorithms in this research, while suggesting the appropriate algorithm, led to reliable and valuable knowledge in classifying high-quality aerospace researchers. [ABSTRACT FROM AUTHOR]

The truss static structure system has excellent large load and lightweight characteristics. It is easy to embed actuators by substituting specific members in the structure and has the potential for multidimensional space deformation. Inspired by uniform tessellation structures, this article proposes a novel shape morphing mechanism (SMM) based on the combined design of tetrahedral-octahedral heterogeneous units (TOHUs). The relationship between the motion properties and driving configuration of the tetrahedral-octahedral units is analyzed to determine their conceptual configuration based on graph theory. Then, the weighted graph, adjacency matrix, and connection rules are evaluated to synthesize the conceptual structure for the truss mechanism. The results show that this configuration can allow multidimensional continuous deformations, including span, bend, sweep, and twist. A prototype is built to verify its deformability. Finally, the stiffness performance is analyzed based on the matrix displacement method. This research provides a comprehensive design method for constructing SMM, expands the range of combinable units and connection methods, and offers theoretical guidance for the innovative design of multidimensional deformation SMM in aerospace. [ABSTRACT FROM AUTHOR]

Aircraft in both the commercial and defense sectors undergo significant disassembly in order to access and inspect critical structures and components. To limit the extent of disassembly needed and thus increase system availability, the concept of mobile robotic inspection has been notionally discussed for over 20 years. Notably this interest in mobile robotic inspection extends beyond aircraft to include civil infrastructure, pipelines, and nuclear plants where some robotic platforms are currently in use. However, the unique challenges associated with complex aircraft systems and structures remain to be addressed. With advancements in the fields of durable polymers, autonomous materials, flexible electronics, tailorable actuation, and others, soft robotics are an increasingly viable solution to the challenge of inspection in access-limited spaces. This perspective article will overview key advancements in pertinent technical areas and highlight scientific barriers to wide-spread use and acceptance of soft robotics for aircraft inspection. [ABSTRACT FROM AUTHOR]

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Nanoclays, a specific type of nanomaterial, have emerged as versatile and dynamic materials, with tremendous potential for advanced functional applications. Despite publishing a large number of research articles, there are relatively few review articles on this topic. This comprehensive review delves into the most widely used nanoclays and explores the diverse range of applications in different fields, such as aerospace, automobile, construction, biomedical, food packaging, and polymer composites. With their ability to enhance the performance of materials and products, nanoclays have become a highly desired material in various industries. The challenges associated with nanoclays like complex properties, difficulty in developing new synthesis methods, and challenges in investigating long‐term durability and stability have been summarized. The future research directions with the exciting possibilities to develop future innovative materials have been highlighted at the end of the article. Highlights: This review provides an extensive examination of the most widely used nanoclays, detailing their properties, types, and limitations.A summary of publication trends over the last 15 years, based on Scopus data up to 2024, indicates growing interest and research output in nanoclays.Applications of nanoclays span across aerospace, automobile, construction, biomedical, food packaging, and polymer composites, showcasing their versatility.Key challenges discussed include complex properties, difficulties in new synthesis methods, and issues in long‐term durability and stability.Future research directions highlight the potential for developing innovative materials using nanoclays. [ABSTRACT FROM AUTHOR]

The Pakistani aerospace industry is embracing digitalisation (within a year), utilising budgets of less than 5% of the company’s annual revenue; however, no industry claims that these technologies have been adopted to a large extent across their R&D, production/manufacturing, MRO, and services/distributor functions. According to 67% of respondents, there are no regulations, laws, or other government policies pertaining to Industry 4.0. Technological preparedness in the form of suitable software and hardware was highlighted as the main critical success factor, while Cybersecurity and cloud computing were identified as essential implementation tools. The originality and value of this study lie in it being the first study of its type on Industry 4.0 within the Pakistani aerospace sector. This research will serve as a strategic tool for policymakers, industry leaders, and stakeholders to guide informed decision-making and propel the aerospace sector towards sustainable growth and competitiveness.

Abstract Nanoclays, a specific type of nanomaterial, have emerged as versatile and dynamic materials, with tremendous potential for advanced functional applications. Despite publishing a large number of research articles, there are relatively few review articles on this topic. This comprehensive review delves into the most widely used nanoclays and explores the diverse range of applications in different fields, such as aerospace, automobile, construction, biomedical, food packaging, and polymer composites. With their ability to enhance the performance of materials and products, nanoclays have become a highly desired material in various industries. The challenges associated with nanoclays like complex properties, difficulty in developing new synthesis methods, and challenges in investigating long‐term durability and stability have been summarized. The future research directions with the exciting possibilities to develop future innovative materials have been highlighted at the end of the article. Highlights This review provides an extensive examination of the most widely used nanoclays, detailing their properties, types, and limitations. A summary of publication trends over the last 15 years, based on Scopus data up to 2024, indicates growing interest and research output in nanoclays. Applications of nanoclays span across aerospace, automobile, construction, biomedical, food packaging, and polymer composites, showcasing their versatility. Key challenges discussed include complex properties, difficulties in new synthesis methods, and issues in long‐term durability and stability. Future research directions highlight the potential for developing innovative materials using nanoclays.

The aerospace industry and technology are always considered one of the country’s most important and valuable industries. The research area of "Aerospace" is among the priorities of the grand science and technology development strategies, and addressing it is strategically vital. The present research aims to estimate and predict the appropriate algorithm for identifying high-quality aerospace researchers based on Advanced Ensemble Classifier Techniques (AECT) in data mining on the outputs of scientometric analyses and predicting the most essential scientometric-related metrics to identify high-quality researchers. The present study was performed using the protocols of applied research and multiple methods. The studied population includes all aerospace researchers (1945 and 2021) indexed in "The Web of Science Core Collection (WOSCC)". DataLab software and multiple programming languages have been applied in this research. All three algorithms have an accuracy of 0.96 and an F1-score of 0.97, which indicates that the models have high accuracy, validity, sensitivity, and predictive power. The "Blending" algorithm is considered a suitable and predictive model. The output of the LightGBM algorithm is that the most important and robust metric in the evaluation of prominent researchers is a metric from the researchers' effectiveness dimension, the Q parameter. According to the knowledge obtained from the ability to predict AECT in the prediction of high-quality researchers, it is possible to use the metrics mentioned in the evaluation of researchers in the field of scientometrics for more accurate and comprehensive prediction. An algorithm that can lead to the optimal and efficient classification of researchers provides the possibility of in-depth analysis of the available data about researchers and smooths the predictive power of the most high-quality researcher. The use of the proposed algorithms in this research, while suggesting the appropriate algorithm, led to reliable and valuable knowledge in classifying high-quality aerospace researchers.

Purpose: Today, researchers encounter challenges in scientific collaboration and the alignment of results with their peers. This study aims to evaluate the accuracy of identification and the extent of researchers' genuine participation in the convergence of multi-authored articles written by aerospace researchers, utilizing the three-dimensional Collaborative Author Writing Hierarchy (CAWH). Author associativity is a concept closely linked to scientific collaboration and multi-authored publications. The complexity of knowledge and the increasing demand for specialization and interdisciplinary skills have shaped scientific participation. Aerospace researchers and specialists are pivotal in conducting scientific and industrial research within the aerospace sector, focusing on technology development and providing support and guidance to fellow researchers. The aerospace industry is multi-faceted, strategic, and dynamic, possessing significant potential for wealth generation, economic development, enhancing national competitiveness on the global stage, job creation, and export opportunities. In various fields of study, numerous indicators have been established for observing, monitoring, and quantitatively and qualitatively evaluating researchers' publications, leading to the introduction of diverse metrics accordingly.Methodology: The research is applied in nature and employs an analytical approach. To assess the improvement in accurately identifying the author's true contributions in published articles, a composite measure that examines multiple dimensions has been utilized. The research outputs of aerospace researchers were analyzed, drawing on data categorized under "Engineering, Aerospace" in the Web of Science Core Collection (WOSCC). English-language articles published from 1945 to 2021 were extracted for this study. Data extraction was conducted on February 4, 2022, a Friday. The current research community encompasses all aerospace researchers from 1945 to 2021, comprising 153,994 records indexed in the Web of Science Core Collection (WOSCC). The total number of authors is 161,156, of whom 154,450 researchers with identifiable names (without sampling) were examined. The total number of citations is 2,617,712. Data extracted from the scientific website during the research period were analyzed. In this research, two tools, namely the "MiMFa Scraper, were employed to gather detailed information about each author. Additionally, another tool was utilized to match the gauge information with PHP (Hypertext Preprocessor). This tool is considered part of the DataLab software suite. Ravar PreMap software was also used to standardize the data. To normalize the data, the codes developed in the DataLab software were implemented. Excel 2016 was also utilized to extract data from various websites using PHP. The CAWH measure is defined as the average number of weighted citations based on co-author credit for a researcher.Findings: The results of the H-weighted co-authorship index indicate "Florian Menter" (from ANSYS Germany GmbH), "Chae M. Rhie" (from Raytheon Technologies USA), "Philippe R. Spalart" (from Boeing), "Edward F. Crawley" (from Massachusetts (from the Institute of Technology (MIT)), "Irving Reed" (from university (from Southern California) are in rank fifth ranks of among based on the CAWH index. This measure was used to calculate the utilizing assessment of each author in writing a multi-author article.Conclusion: The emphasis on recognizing researchers' contributions in article writing will be beneficial and effective for both researchers and the scientific community. Acknowledging researchers' involvement in writing allows them to showcase their contributions and achievements fairly and transparently. This approach enables researchers to properly receive their scientific credit and build their reputation, thereby gaining a competitive advantage within scientific communities. Within research teams, the implementation of this measure will enhance collaboration, facilitate the division of labor, and more equitably determine the rights and benefits of each team member. This approach fosters active collaboration and enhances the productivity of research teams. It enables research organizations and universities to conduct more accurate scientific evaluations of individuals and allocate resources based on equitable distribution and participation. Additionally, this method can improve transparency and build trust within research organizations. Consequently, it can help cultivate a culture of participation and cooperation within scientific communities. This approach can foster healthy, justice-oriented competition in science and enhance the quality of research. The evaluation offers readers and the scientific community detailed information about the authors and their collaborators involved in the research. This transparency enables readers to better assess the contributions and expertise of the article’s authors, thereby increasing their trust in the results and citations presented. Overall, acknowledging the participation of researchers in writing articles supports the scientific process and advances the field of science. This approach offers guidance for justice, transparency, cooperation, and the enhancement of research quality within scientific communities. It fosters an environment conducive to scientific development and progress, which can be assessed and refined using the index introduced in this study.

The paper presents a wireless system integrated with a machine learning (ML) model for structural health monitoring (SHM) of carbon fiber reinforced polymer (CFRP) structures, primarily targeting aerospace applications. The system collects data via carbon nanotube (CNT) piezoresistive sensors embedded within CFRP coupons, wirelessly transmitting these data to a central server for processing. A deep neural network (DNN) model predicts mechanical properties and can be extended to forecast structural failures, facilitating proactive maintenance and enhancing safety. The modular design supports scalability and can be embedded within digital twin frameworks, offering significant benefits to aircraft operators and manufacturers. The system utilizes an ML model with a mean absolute error (MAE) of 0.14 on test data for forecasting mechanical properties. Data transmission latency throughout the entire system is less than one second in a LAN setup, highlighting its potential for real-time monitoring applications in aerospace and other industries. However, while the system shows promise, challenges such as sensor reliability under extreme environmental conditions and the need for advanced ML models to handle diverse data streams have been identified as areas for future research.

Geopolymers are cementitious materials with exceptional mechanical and physical properties, making them suitable for aerospace applications. Considering their excellent performance, the present investigation aims to develop geopolymers with designed physical properties to address some issues in the aerospace industry. In this sense, the influence of the alkaline activator on the final properties was evaluated. For the development of the geopolymers, sodium hydroxide and sodium metasilicate solutions were preparedto obtain the alkaline activator. The synthesis process also consisted of a mixing stage using a mixer to obtain a homogenous paste. After mixing, the curing process consisted of a first thermal treatment at 60 °C for 4 h to evaporate the excess water, avoid excessive contraction, and promote strength at early ages. Subsequently, the geopolymers were left at rest for 28 days until the final properties were achieved. The influence of the solid-to-liquidratio (S/L) on the microstructure of the geopolymers was evaluated. For this purpose, X-ray fluorescence spectrometry, X-ray diffraction, and infrared spectrometry analyses were performed. The results show that the content of the alkaline activator promotes variations inthe presence of different crystalline phases, which is more noticeable as the S/L ratio increases. Likewise, the infrared spectra display peaks at different wavelengths regarding the variations in elemental composition, which are more evident with the changes in the S/L ratio. In addition, physical studies, such as thermal conductivity and resistance to gamma radiation were conducted for different geopolymer compositions. The results indicate that changes in properties are not too sensitive to compositional variations, although slight modifications exist. Finally, these studies are significant as aerospace-focused materials are directly exposed to this kind of phenomena. The designed geopolymers have to be able to resist and maintain their properties through exposure to any energy.

Exposure to high levels of radiation can cause acute, long-term health effects, such as acute radiation syndrome, cancer, and cardiovascular disease. This is an important occupational hazard in different fields, such as the aerospace and healthcare industry, as well as a crucial burden to overcome to boost space applications and exploration. Protective bulky equipment made of heavy metals is not suitable for many advanced purporses, such as mobile devices, wearable shields, and manned spacecrafts. In the latter case, the in-space manufacturing of protective shields is highly desirable and remains an unmet need. Composites made of polymers and high atomic number fillers are potential means for radiation protection due to their low weight, good flexibility, and good processability. In the present work, we developed electrospun composites based on polycaprolactone (polymer matrix) and tungsten powder for application as shielding materials. Electrospinning is a versatile technology that is easily scalable at an industrial level and allows obtaining very lightweight, flexible sheet materials for wearables. By controlling tungsten powder size, we engineered homogeneous, stable and processable suspensions to fabricate radiation composite shielding sheets. The shielding capability was assessed by an in vivo model on prototype composite sheets containing 80 w% of W filler in a polycaprolactone (PCL) fibrous matrix by means of irradiation tests (X-rays) on mice. The obtained results are promising; as expected, the shielding effectivity of the developed composite material increases with the thickness/number of stacked layers. It is worth noting that a thin barrier consisting of 24 layers of the innovative shielding material reduces the extent of apoptosis by 1.5 times compared to the non-shielded mice. [ABSTRACT FROM AUTHOR]

The decentralization of production processes organized in global supply chains has made it possible to connect the different levels through industrial digitalization, an evolution derived from the Fourth Industrial Revolution which incorporates enabling technologies. This context raises the need to analyze sectors that, due to the complexity of their projects, require more efficient supply chain management. Two clear examples of these sectors are aerospace and shipbuilding, which demand greater efficiency and sustainability in their operations. The main objective of this study is to compare these two sectors to evaluate the degree of sustainability of their supply chains and how Industry 4.0 technologies have contributed to achieving these goals. To perform this, the Delphi method will be used, a tool that collects information through expert opinions, which will provide key indicators for the comparison. The use of this method will facilitate the identification of convergences and divergences in the management of sustainability in both sectors. Through this analysis, the expected results will reflect the specific needs of each industry in terms of productivity and sustainability. Thus, the study will offer a comprehensive view of how the aerospace and shipbuilding sectors can move toward more sustainable and efficient production models, integrating Industry 4.0 concepts and improving the management of their global supply chains. [ABSTRACT FROM AUTHOR]

This paper provides the necessary and sufficient conditions for a multi-degrees-of-freedom linear potential system with an arbitrary damping matrix to be uncoupled into independent subsystems of at most two degrees-of-freedom using a real orthogonal transformation. The incorporation of additional information about the matrices, which many structural and mechanical systems commonly possess, shows a reduction in the number of these conditions to three. Several new results are obtained and are illustrated through examples. A useful general form for the damping matrix is developed that guarantees the uncoupling of such systems when they satisfy just two conditions. The results provided herein lead to new physical insights into the dynamical behavior of potential systems with general damping matrices and robust computational procedures. It is shown that the dynamics of a damped potential system in which the damping matrix may be arbitrary is identical to that of a damped gyroscopic potential system with a symmetric damping matrix. This brings, for the first time, these two systems, which are seen today as belonging to different categories of dynamical systems, under a unified framework. [ABSTRACT FROM AUTHOR]

Although scholars often portray Mexico as caught in the "middle-income trap," this description obscures important subnational variation in patterns of economic development. We leverage this variation by examining the case of Querétaro, a state with high levels of structural transformation and economic growth since the 1980s. We reconstruct the historical trajectory of its two leading industries, automotive and aerospace. We observe that while both have cumulatively delivered real developmental gains, each also exhibits a complex mix of strengths and weaknesses. We further find that these industries' advancements and hindrances over time appear closely related to the kinds of "partial" coalitions — groups of actors from the state, private firms, and civil society organizations such as labor unions — which participate in industry-level decision-making. Both industries saw periods of "upgrading" when the partial coalitions supporting them were expanding their cognitive diversity while avoiding gross imbalances in the distribution of power among their members. They likewise experienced periods of stagnation when either of those coalition conditions underwent major change. These findings suggest that debates on escaping the middle-income trap should consider how changes in partial political coalitions affect policy models and options. [ABSTRACT FROM AUTHOR]

Purpose: Today, researchers encounter challenges in scientific collaboration and the alignment of results with their peers. This study aims to evaluate the accuracy of identification and the extent of researchers' genuine participation in the convergence of multi-authored articles written by aerospace researchers, utilizing the three-dimensional Collaborative Author Writing Hierarchy (CAWH). Author associativity is a concept closely linked to scientific collaboration and multi-authored publications. The complexity of knowledge and the increasing demand for specialization and interdisciplinary skills have shaped scientific participation. Aerospace researchers and specialists are pivotal in conducting scientific and industrial research within the aerospace sector, focusing on technology development and providing support and guidance to fellow researchers. The aerospace industry is multi-faceted, strategic, and dynamic, possessing significant potential for wealth generation, economic development, enhancing national competitiveness on the global stage, job creation, and export opportunities. In various fields of study, numerous indicators have been established for observing, monitoring, and quantitatively and qualitatively evaluating researchers' publications, leading to the introduction of diverse metrics accordingly. Methodology: The research is applied in nature and employs an analytical approach. To assess the improvement in accurately identifying the author's true contributions in published articles, a composite measure that examines multiple dimensions has been utilized. The research outputs of aerospace researchers were analyzed, drawing on data categorized under "Engineering, Aerospace" in the Web of Science Core Collection (WOSCC). English-language articles published from 1945 to 2021 were extracted for this study. Data extraction was conducted on February 4, 2022, a Friday. The current research community encompasses all aerospace researchers from 1945 to 2021, comprising 153,994 records indexed in the Web of Science Core Collection (WOSCC). The total number of authors is 161,156, of whom 154,450 researchers with identifiable names (without sampling) were examined. The total number of citations is 2,617,712. Data extracted from the scientific website during the research period were analyzed. In this research, two tools, namely the "MiMFa Scraper, were employed to gather detailed information about each author. Additionally, another tool was utilized to match the gauge information with PHP (Hypertext Preprocessor). This tool is considered part of the DataLab software suite. Ravar PreMap software was also used to standardize the data. To normalize the data, the codes developed in the DataLab software were implemented. Excel 2016 was also utilized to extract data from various websites using PHP. The CAWH measure is defined as the average number of weighted citations based on coauthor credit for a researcher. Findings: The results of the H-weighted co-authorship index indicate "Florian Menter" (from ANSYS Germany GmbH), "Chae M. Rhie" (from Raytheon Technologies USA), "Philippe R. Spalart" (from Boeing), "Edward F. Crawley" (from Massachusetts (from the Institute of Technology (MIT)), "Irving Reed" (from university (from Southern California) are in rank fifth ranks of among based on the CAWH index. This measure was used to calculate the utilizing assessment of each author in writing a multi-author article. Conclusion: The emphasis on recognizing researchers' contributions in article writing will be beneficial and effective for both researchers and the scientific community. Acknowledging researchers' involvement in writing allows them to showcase their contributions and achievements fairly and transparently. This approach enables researchers to properly receive their scientific credit and build their reputation, thereby gaining a competitive advantage within scientific communities. Within research teams, the implementation of this measure will enhance collaboration, facilitate the division of labor, and more equitably determine the rights and benefits of each team member. This approach fosters active collaboration and enhances the productivity of research teams. It enables research organizations and universities to conduct more accurate scientific evaluations of individuals and allocate resources based on equitable distribution and participation. Additionally, this method can improve transparency and build trust within research organizations. Consequently, it can help cultivate a culture of participation and cooperation within scientific communities. This approach can foster healthy, justice-oriented competition in science and enhance the quality of research. The evaluation offers readers and the scientific community detailed information about the authors and their collaborators involved in the research. This transparency enables readers to better assess the contributions and expertise of the article’s authors, thereby increasing their trust in the results and citations presented. Overall, acknowledging the participation of researchers in writing articles supports the scientific process and advances the field of science. This approach offers guidance for justice, transparency, cooperation, and the enhancement of research quality within scientific communities. It fosters an environment conducive to scientific development and progress, which can be assessed and refined usisng the index introduced in this study. [ABSTRACT FROM AUTHOR]

Geopolymers are cementitious materials with exceptional mechanical and physical properties, making them suitable for aerospace applications. Considering their excellent performance, the present investigation aims to develop geopolymers with designed physical properties to address some issues in the aerospace industry. In this sense, the influence of the alkaline activator on the final properties was evaluated. For the development of the geopolymers, sodium hydroxide and sodium metasilicate solutions were preparedto obtain the alkaline activator. The synthesis process also consisted of a mixing stage using a mixer to obtain a homogenous paste. After mixing, the curing process consisted of a first thermal treatment at 60 °C for 4 h to evaporate the excess water, avoid excessive contraction, and promote strength at early ages. Subsequently, the geopolymers were left at rest for 28 days until the final properties were achieved. The influence of the solid-to-liquidratio (S/L) on the microstructure of the geopolymers was evaluated. For this purpose, X-ray fluorescence spectrometry, X-ray diffraction, and infrared spectrometry analyses were performed. The results show that the content of the alkaline activator promotes variations inthe presence of different crystalline phases, which is more noticeable as the S/L ratio increases. Likewise, the infrared spectra display peaks at different wavelengths regarding the variations in elemental composition, which are more evident with the changes in the S/L ratio. In addition, physical studies, such as thermal conductivity and resistance to gamma radiation were conducted for different geopolymer compositions. The results indicate that changes in properties are not too sensitive to compositional variations, although slight modifications exist. Finally, these studies are significant as aerospace-focused materials are directly exposed to this kind of phenomena. The designed geopolymers have to be able to resist and maintain their properties through exposure to any energy. [ABSTRACT FROM AUTHOR]

This study investigates the drag coefficient of three models of suborbital rockets with different nosecones. A test section allowing for force measurement of a 1:50 scale rocket model was designed with the aid of numerical simulations. The velocity obtained in the wind tunnel corresponds with a Mach number of 2.45. RANS simulations were used in verifying operating parameters, as well as testing the support configurations for connecting the model with the bottom wall of the tunnel section. Pressure distribution measurements on the top and bottom walls of the wind tunnel matched simulation results well. The shock structure in the test section was visualized using the schlieren technique, revealing that the measured angle of the main shock generated at the tip of the rocket matched the simulation data. Finally, the measured forces were compared with simulations for one of the nosecone configurations. Despite very good agreement for pressure distribution on the wind tunnel walls and shock structure, a significant mismatch in the forces measured was nevertheless observed: the simulated CD (0.57) being four times larger than that obtained in measurements (0.138). Further analysis of the test section is required to pinpoint the source of discrepancies and redesign the force measurement system to achieve improved force results. [ABSTRACT FROM AUTHOR]