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Designing new aircraft that are state-of-the-art and beyond always requires the development of new technologies. This paper aims to present lessons learned while designing, building and testing new UAVs in the configuration of the flying wing. The UAV contains a number of aerodynamic devices that are not obvious solutions and use the latest manufacturing technology achievements, such as 3D printing.

The design solutions were applied on an airworthy aircraft and checked during test flights. The process was first conducted on the smaller UAV, and based on the test outcomes, improvements were made and then applied on the larger version of the UAV, where they were verified.

A number of practical findings were identified. For example, the use of 3D printing technology for manufacturing integrated pressure ports, investigation of the adverse yaw effect on the flying wing configuration and the effectiveness of winglet rudders in producing yawing moment.

All designed devices were tested in practice on the flying aircraft. It allowed for improved aircraft performance and handling characteristics. Several of the technologies used improved the speed and quality of aerodynamic device design and manufacturing, which also influences the reliability of the aircraft.

The paper presents how 3D printing technology can be utilized for manufacturing of aerodynamic devices. Specially developed techniques for control surface design, which can affect adverse yaw problem and aircraft handling characteristics, were described.

This study aims to achieve optimum flow separation control for a road vehicle using a reverse flow fan on rear side.

A full-length reverse flow fan array (fan’s air speed is 50% of the car’s speed) is attached throughout the width of the vehicle at rear edge corner.

The reverse flow fan array positioned at rear edge of car pushes the airflow against the car’s rear window. It creates the recirculation region and alters the pressure distribution. This reduces the lift coefficient by 150%, which becomes the downforce and reduces the drag coefficient by 22%. As the car speed increases, fan speed should also be increased for effective flow control.

This active flow control method for 3D Ahmed car body has been studied computationally at low speed (40 m/s).

This design increases the downforce, thus gives better cornering speed and stability, and decreases the drag which improves fuel efficiency. It can be used for effective flow control of cars (hatchback/sedan). The findings can be applied to the bluff bodies, road vehicles, UAV and helicopter fuselage for flow separation control.

The fan array is attached on car’s rear side, which blows air against the car’s rear window. It alters the pressure distribution and aerodynamics forces favorably. But the existing high-speed fan used in a sports cars sucks the air from bottom and pushes it rearward, which increases both the traction force and drag.

Extensive empirical evidence suggests that procedural justice (PJ) and distributive justice (DJ) are key success factors for achieving durable peace negotiations. This paper aims to investigate how complexity affects these factors and the outcomes in negotiations.

The qualitative study is based on an examination of the peace negotiations that led to the 2016 agreement between the Fuerzas Armadas Revolucionarias de Colombia – Ejército del Pueblo and the Colombian Government. Based on document analysis, the authors examined in detail how and where in the process the principles of PJ and DJ were applied. The authors then examined the implementation progress after 2016 and placed the peace process in the overall context of the Colombian conflict.

The authors found that the principles of PJ and DJ were present in both the negotiation process and the agreement. The negotiations were successful and satisfactory solutions could be found for all issues. The complexity of the conflict is reflected in the limited coverage of the peace negotiations. Not all groups, interests and subconflicts could be included in the negotiations. This limits their contribution to a durable peace in Colombia. Conflicts that remain unresolved also have a negative effect on the implementation of the agreement.

For conflict management, this implies that the negotiations should not be viewed as “one-and-done” but rather as a progressive, ongoing process. The agreement is only the nucleus for achieving total peace. It must be actively advanced and defended.

This study offers new qualitative insights into how PJ and DJ function in negotiations. It also establishes a systematic connection between PJ and DJ and complexity, introduces the notion of coverage and, thereby, opens a new perspective on the management of conflict complexity.

In this study, STEM resources reviewed in Goodreads were investigated to determine their authorship, linguistic characteristics and impact. The analysis reveals gender disparity favoring titles with male authors.

This paper applies theoretical concepts of knowledge commons to understand how individuals leverage the affordances of the Goodreads platform to share their perceptions of STEM-related books.

The analysis reveals gender disparity favoring titles with male authors. Female-authored STEM publications represent popular science nonfiction and juvenile genres. Analysis of the scholarly impact of the reviewed titles revealed that Google Scholar provides broader and more diverse coverage than Web of Science. Linguistic analysis of the reviews revealed the relatively low aesthetic disposition of reviewers with an emphasis on embodied experiences that emerged from the reading.

This study contributes to the understanding of the impact of popular STEM resources as well as the influence of the language of user-generated reviews on production, consumption and discoverability of STEM titles.

The notion that disasters are not natural is longstanding, leading to a growing number of campaigns aimed at countering the use of the term “natural disaster.” Whilst these efforts are crucial, critical perspectives regarding the potential risks associated with this process are lacking, particularly in places affected by violent conflict. This paper aims to present a critical analysis of these efforts, highlighting the need to approach them with care.

The author draws upon insights and discussions accumulated over a decade of research into the relationship between disasters and conflict. The article includes a critical literature review on the disaster–conflict relationship and literature specifically addressing the idea that disasters are not natural. The analysis of field notes led to a second literature review covering topics such as (de) politicisation, instrumentalisation, disaster diplomacy, ethics, humanitarian principles, disaster risk reduction, peacebuilding and conflict sensitivity.

This analysis underscores the importance of advocating that disasters are not natural, especially in conflict-affected areas. However, an uncritical approach could lead to unintended consequences, such as exacerbating social conflicts or obstructing disaster-related actions. The article also presents alternatives to advance the understanding that disasters are not natural whilst mitigating risks, such as embracing a “do-no-harm” approach or conflict-sensitive analyses.

The author offers an innovative critical approach to advancing the understanding that disasters are not natural but socio-political. This perspective is advocated, especially in conflict-affected contexts, to address the root causes of both disasters and conflicts. The author also invites their peers and practitioners to prioritise reflective scholarship and practices, aiming to prevent the unintentional exacerbation of suffering whilst working towards its reduction.

This study aims to evaluate the development of composites made of epoxy (E) resin with different weight percentages of polypropylene (PP) and graphene oxide (Go) to form nanocomposite plates.

A hand lay-up process was used to develop 21 different composites, with varying concentrations of PP (5%–35%) and Go (5%–35%). A ternary composite of E matrix was produced by combining binary fillers PP and Go (5%–35%) in a 1:1 ratio to a (95%–5%) solution. With the help of adopting the melt condensation deal to extract Go, the modified Hummers method was used to make Go platelets.

Through field emission scanning electron microscopy (FESEM) and X-ray diffraction investigations, the particulate’s size and structural characteristics were identified. Based on the FESEM analysis of the collapsed zones of the composites, a warp-and-weft-like structure is evident, which endorses the growth yield strength, flexural modulus and impact strength of the composites.

The developed nanocomposites have exceptional mechanical capabilities compared to plain E resin, with E resin exhibiting better tensile strength, modulus and flexural strength when combined with 10% PP and 10% Go. When compared to neat E resin, materials formed from composites have exceptional mechanical properties. When mixed with 10% PP and 10% Go, E resin in particular displays improved tensile strength (23 MPa), tensile modulus (4.15 GPa), flexural strength (75.6 MPa) and other attributes. Engineering implications include automobile side door panels, spacecraft applications, brake pads and flexible battery guards.