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In recent years, increased use of all-aspect infrared (IR)-guided missiles based on the long-wave infrared (LWIR; 8–12 µm) band has lowered the probability of aircraft survival in warfare. The lock-on of these highly sensitive missiles is difficult to break, especially from the front. Aerodynamically heated swept-back leading edges (SBLE), because of their high temperature and large area, serve as a prominent LWIR source for aircraft detection from the front. This study aims to report the influence of sweep-back angle (Λ, based on the Mach number [M_∞]) on aerodynamic heating and the LWIR signature of SBLE.

The temperature along SBLE is obtained numerically as radiation equilibrium temperature (T_w) by discretizing the SBLE length into “n” number of segments, and for each segment, emission based on T_w is evaluated. IR radiance due to reflected external sources (sky-shine and Earthshine) and radiance due to T_w are collectively used to determine the IR contrast between SBLE and its replaced background in the LWIR band (i_{cont-SBLE,LWIR}).

The results are obtained for low subsonic turboprop aircraft (Λ = 3°, M_∞ = 0.44); high subsonic strategic bombers (Λ = 35°, M_∞ = 0.8); fifth-generation stealth aircraft (Λ = 40°, M_∞ = 1.6); and aircraft with supercruise/supersonic capability (Λ = 50°, M_∞ = 2.5). The aircraft with supersonic capability (Λ = 50°, M_∞ = 2.5) reports the maximum LWIR signatures and hence the highest visibility from the front. The results obtained are compared with values at Λ = 0° for all cases, which shows that increasing Λ significantly reduces aerodynamic heating and LWIR signatures.

The novelty of this study comes from its report on the influence of Λ on the LWIR signatures of aircraft SBLE in the frontal aspect for the first time.

Heavy rainfall is one of the main causes of the degradation of historic rammed Earth architecture. For this reason, ensuring the conservation thereof entails understanding the factors involved in these risk situations. The purpose of this study is to research three past events in which rainfall caused damage and collapse to historic rammed Earth fortifications in Andalusia in order to analyse whether it is possible to prevent similar situations from occurring in the future.

The three case studies analysed are located in the south of Spain and occurred between 2017 and 2021. The hazard presented by rainfall within this context has been obtained from Art-Risk 3.0 (Registration No. 201999906530090). The vulnerability of the structures has been assessed with the Art-Risk 1 model. To characterise the strength, duration, and intensity of precipitation events, a workflow for the statistical use of GPM and GSMaP satellite resources has been designed, validated, and tested. The strength of the winds has been evaluated from data from ground-based weather stations.

GSMaP precipitation data is very similar to data from ground-based weather stations. Regarding the three risk events analysed, although they occurred in areas with a torrential rainfall hazard, the damage was caused by non-intense rainfall that did not exceed 5 mm/hour. The continuation of the rainfall for several days and the poor state of conservation of the walls seem to be the factors that triggered the collapses that fundamentally affected the restoration mortars.

A workflow applied to vulnerability and hazard analysis is presented, which validates the large-scale use of satellite images for past and present monitoring of heritage structure risk situations due to rain.

The purpose of the present work is to study the impacts of rapid cooling and Tb rare-earth additions on the structural, thermal and mechanical behavior of Bi–0.5Ag lead-free solder for high-temperature applications.

Effect of rapid solidification processing on structural, thermal and mechanical properties of Bi-Ag lead-free solder reinforced Tb rare-earth element.

The obtained results indicated that the microstructure consists of rhombohedral Bi-rich phase and Ag99.5Bi0.5 intermetallic compound (IMC). The addition of Tb could effectively reduce the onset and melting point. The elastic modulus of Tb-containing solders was enhanced to about 90% at 0.5 Tb. The higher elastic modulus may be attributed to solid solution strengthening effect, solubility extension, microstructure refinement and precipitation hardening of uniform distribution Ag99.5Bi0.5 IMC particles which can reasonably modify the microstructure, as well as inhibit the segregation and hinder the motion of dislocations.

It is recommended that the lead-free Bi-0.5Ag-0.5Tb solder be a candidate instead of common solder alloy (Sn-37Pb) for high temperature and high performance applications.

The purpose of this commentary is to complete the synthesis of the United Nations 17 Sustainable Development Goals (SDGs) into Seven Commentaries on Service Research Themes developed by ServCollab and the Journal of Services Marketing. As an approach to achieving SDG #17, ServCollab’s collaborative logic and design perspective for collaboration services for sustainable development partnerships are presented.

Collaboration is ServCollab’s Service Research Theme #7, which reframes the UN SDG meta goal #17 of Partnerships. In prior ServCollab research, four possible human interactions were identified: conflict, competition, cooperation and collaboration. Only the shared purpose of collaboration enables elevating the human experience.

The authors found no published service research that studied SDG #17, which means there are huge opportunities for service research on the role of collaboration in service systems. The alignment between the UN SDGs and ServCollab’s goals is explored. A research agenda for service research and SDG goals was proposed for collaborative communications, collaborative technologies and collaborative projects.

Practical ideas are offered for serving humanity through collaboration. Collaborations are the only practical solutions to humanity’s myriad sustainable development problems.

When the United Nations developed its first 16 SDGs, they knew that accomplishing these goals required complex collaborations. That is why SDG #17 is Partnerships. ServCollab’s serving humanity logic applies collaboration to all social settings (large or small) where working together can sustain and regenerate the service ecosystem of Planet Earth.

This commentary describes a unique approach to building collaborative capacity for conducting service research projects for sustaining and regenerating the service ecosystem of Planet Earth.

This editorial aims to organise the 17 United Nations Sustainable Development Goals (SDGs) into seven ServCollab service research themes to provide a way forward for service research that improves human and planetary life.

A conceptual approach is used that draws on observations from the scholarly experience of the editors.

This editorial offers seven research themes for service researchers: services that enable the WELL-BEING of the human species; services that provide OPPORTUNITY for all humans; services that manage RESOURCES for all humans; ECONOMIC services for work and growth for all humans; services from INSTITUTIONS that offer fair and sustainable living for all humans; service ecosystems with the PLANET; and COLLABORATION services for sustainable development partnerships.

Service scholars are urged to pursue collaborative research that reduces suffering, improves well-being and enables well-becoming for the sustainability and prosperity of Planet Earth.

This editorial provides service scholars with a new framework synthesising the SDGs into research themes that help focus further service research.

This study aims to define a “technological statecraft” concept to distinguish tech-based measures/sanctions from an array of economic measures ranging from restrictions of rare earth elements and natural gas supplies to asset freezes under the wider portfolio of economic statecraft. This concept is practically intended to reveal the USA’s “logic of choice” in its employment of technology as an efficient instrument to deal with China in the context of the great power rivalry.

This study follows David A. Baldwin’s statecraft definition and conceptualization methodology, which relies on “means” rather than “ends.” In addition to Baldwin and as an incremental contribution to his economic statecraft analysis, this study also combines national political economy with statecraft analysis with a particular focus on the utilization of technological measures against China during the Trump administration.

The US rationale for choosing technology, namely, emerging and foundational technologies, in its rivalry against China is caused at least by two factors: the nature of the external challenge and the characteristics of the US innovation model based largely on radical innovations. To deal with China, the USA practically distinguished the role of advanced technology and followed a grammer of technological statecraft as depicted in the promulgated legal texts during the Trump administration.

Despite a growing volume of literature on economic statecraft and technological competition, studies focusing on countries’ “logic of choice” with regard to why and under what conditions they choose financial, technological or commodity-based sanctions/measures/controls are lacking. Inspired from Baldwin’s account on the “logic of choice” from among alternative statecrafts (i.e. diplomacy, military, economic statecraft, and propaganda). This study will contribute to the literature with a clear lens to demonstrate the “logic of choice” from among a variety of economic statecraft measures in the case of the US technological statecraft toward China.

This study aims to investigate the behavior of different types of stone columns, including the short and floating columns, as well as the ordinary and the geosynthetic encased stone columns (OSC and GESC). The effectiveness of the geosynthetic encasement and the impact of the installation using the lateral expansion method on the column performance is evaluated through a three-dimensional (3D) unit cell numerical analysis.

A full 3D numerical analysis is carried out using the explicit finite element code PLAXIS 3D to examine the installation influence on settlement reduction (ß), lateral displacement (U_x) and vertical displacement (U_z) relative to different values of lateral expansion of the column (0% to 15%).

The findings demonstrate the superior performance of GESC, particularly short columns outperforming floating counterparts. This enhanced performance is attributed to the combined effects of geosynthetic encasement and increased lateral expansion. Notably, these strategies contribute significantly to decreasing lateral displacement (U_x) at the column’s edge and reducing vertical displacement (U_z) under the rigid footing.

In contrast to previous studies that examined the installation effect of OSC contexts, this paper presents a comprehensive investigation into the effect of geosynthetic encasement and the installation effects using the lateral expansion method in very soft soil, using 3D numerical simulation. The study emphasizes the significance of the consideration of geosynthetic encasement and lateral expansion of the column during the design process to enhance column performance.

The case is derived from secondary sources, including publicly available reports and information about all companies directly or indirectly engaged in the industry. No primary sources were available.

This teaching case is designed for students to demonstrate their mastery of industry-level analysis in the emerging space tourism industry. It allows students to understand what constitutes the industry within the broader space sector and to apply analytical tools such as PESTEL and Porter’s Five Forces, with the option to discuss strategic groups. Students gain insights into how the industry is evolving within its broader environment and how companies could respond or differentiate themselves. Information is also provided for students to consider the broader social impact of a relatively new industry from the perspective of sustainable development.

The case is written for undergraduate and graduate students enrolled in strategic management courses. The case placement is ideally in conjunction with industry-level analytical frameworks such as Porter’s Five Forces, PESTEL analysis, strategic groups (optional) and industry life cycle. Most strategic management textbooks cover these concepts in the first few chapters. For example, “Strategic Management, 14th edition” by Hill, Schilling and Jones (2023) covers these topics in chapter 2. Given that space tourism is an embryonic industry dependent on technological innovation, instructors might also use this case in innovation or entrepreneurship-related courses. This case could also be used to address critical issues, such as sustainability, in tourism management courses.