Journals
2026 EN
Goli Srikanth · Kurtuluş Dilek Funda · Imran Imil Hamda
+4 more
ABSTRACT With the growing use of unmanned aerial vehicles (UAVs) in both civil and military applications, optimizing electric powertrain systems is essential to enhance endurance, efficiency ( η $$ \eta $$ ), and mission adaptability. This study explores the impact of commercially available propeller variations on UAV powertrain performance, keeping the battery, ESC, and brushless DC motor fixed. The hypothesis is that propeller geometry plays a critical role in thrust production and flight endurance. To validate this, several off‐the‐shelf propellers are experimentally tested using a dynamometer setup that measured thrust, RPM, voltage, and current at various throttle levels. Results show that propeller P3_30 delivered the highest Thrust to Mechanical Power Ratio (TMPR) (8.48%), while P1_26 offered the longest endurance (16.17 min). Notably, efficiency ( η $$ \eta $$ ) peaked at 93.1% for the P1_26 propeller configuration, further supporting its suitability for long‐duration missions. These insights provide a practical performance guide for UAV designers and emphasize the value of experimental benchmarking in selecting propulsion components for mission‐specific UAV configurations.
Journals
2026 EN
Azzawi Itimad D. J. · Khalil Wissam H. · Alabdaly Ibrahim K.
+1 more
ABSTRACT Forced convection and entropy generation through a complex geometry like Cassini oval annuli play a significant role in many applied thermal engineering systems. The novel feature of the present work is a multi‐objective and multi‐response optimal design of the hydrothermal and entropy performance in a porous Cassini oval annular pipe. This approach integrates the response surface methodology (RSM) CFD simulation for evaluating different key design parameters. The variables studied are the inner twisted pipe pitches (0 ≤ P ≤ 1.5), aspect ratios (0.08 ≤ AR ≤ 0.2), porosity (0.1 ≤ ɛ ≤ 0.9), and pore density (5 ≤ PPI ≤ 35) with different Reynolds numbers (50 ≤ Re ≤ 250). These parameters impact heat transfer rate, fluid mixing, and pressure drop. Optimization results indicate that low inner twisted pipe pitch ( p = 0.5), low aspect ratio (AR = 0.08), low pore per inch (PPI = 5), and high porosity ( ɛ = 0.9) are favorable for enhancing hydrothermal performance (NuE = 12.23 and PEC = 3.069) with moderate entropy generation (EG = 0.940). Consequently, this study introduces a useful procedure for optimizing the hydrothermal and thermodynamic performance of forced convection in porous Cassini oval annular pipe cooling systems.
Journals
2026 EN
Botha Barend
ABSTRACT Modern engineered systems demand lifecycle strategies that are responsive, risk‐aware, and aligned with evolving needs. Historically, systems engineering has been methodology‐driven, with formal frameworks such as the V‐Model or waterfall used to guide process rigor and governance. These methodologies provided structure and control, especially for large, safety‐critical engineered programs. However, as systems have become more complex and adaptive, the limitations of rigid methodological adherence have become increasingly apparent. This article retraces the reasoning behind moving from methodology‐driven to function‐driven, to outcomes‐focused, and finally to functionally enabled outcomes. It introduces the concept of functional‐outcomes driven tailoring (FODT) as a unifying framework that drives lifecycle performance through functional alignment to mission outcomes.
Journals
2026 EN
Leibbrandt Wouter · Wesselius Jacco · Beenker Frans
ABSTRACT The high‐tech equipment industry brings complex industrial products to the market with high speed, enhanced functionality, a better cost‐performance ratio, and greater integration into customer workflows. Driven by digitalization, the complexity of these systems continues to grow steeply. To manage this complexity, continuous innovation in systems engineering methodologies is needed. TNO‐ESI targets to 1) create impactful and industrially applicable systems engineering methodologies and 2) provide innovation support to the industry to get these applied in an industrial context. The ESI research program is defined through a roadmapping process that follows two tracks: a roadmap that maps industry needs and related research and development requirements and a roadmap that describes the developments in the expertise areas necessary for addressing these industry needs. In this paper, we describe the ESI mission, our way of working and activities, and explain the roadmapping process and the roadmaps.
Journals
2026 EN
Mosner Felix L. · Sting Fabian J. · Chandrasekaran Aravind
ABSTRACT This multiple case study develops a mid‐range theory on how frontline idea generation is affected by the actions of an organization's middle management. The study draws from four acute‐care hospitals in Germany and involves 36 semi‐structured interviews with representatives from all hierarchy levels. We use mission statements from these hospitals to measure top management's strategic intent regarding frontline idea generation. Then we analyze the idea generation performance of 156 nurses from the hospitals and link it to specific middle management behaviors. The cross‐case analyses reveal that middle managers' shaping of nurses' innovation identity improves nurses' idea generation performance. However, this connection also means that middle managers' own forays into innovation can impede frontline idea generation. We find that middle managers' supportive behavior is largely independent of top management intent, a dynamic that offers both advantages and risks. These insights extend our knowledge about the role of middle managers in frontline idea generation.
Journals
2026 EN
Jurek Martyna · Sund Kristian J. · Rosati Francesco
ABSTRACT Entrepreneurs experience subjective perceptions of uncertainty and other barriers as they attempt to design their business model. These create boundaries of a cognitive nature that entrepreneurs must navigate. It has been suggested that sustainable entrepreneurship is inherently even more uncertain and complex than traditional entrepreneurship. Through semi‐structured interviews, we study the decision‐making of 22 sustainability‐oriented start‐up entrepreneurs. These interviews reveal the perceived barriers and uncertainties they encounter when developing sustainable business models. We identify a multiplicity of perceived barriers but also uncover inherent tensions and emotional responses associated with sustainable entrepreneurship. Our data highlight the trade‐offs between profit and impact priorities, leading to internalized tensions experienced by entrepreneurs. These tensions, along with other identified barriers, contribute to an understanding of bounded sustainable entrepreneurship. In this context, perceived constraints shape and limit entrepreneurial decision‐making, forcing entrepreneurs to constantly renegotiate their understanding of sustainability. We furthermore uncover a multiplicity of individual entrepreneurial motivations. This leads us to propose a typology of sustainable entrepreneurs' identities based on their approaches to profit‐impact tensions. We define four distinct types of sustainable entrepreneurs: the classical entrepreneur, the serial entrepreneur, the solution entrepreneur, and the mission entrepreneur.
Journals
2026 EN
ChiouTan Faye Y. · Li Conrad · Caffrey Jason P.
+2 more
ABSTRACT Introduction/Aim As humans return to the Moon, safe efficient ambulation and fall prevention on the lunar surface are key concerns. The analysis of gait from archived Apollo mission video footage is now possible with pose estimation video analysis software. Thus, this study aims to retrospectively quantify parameters of Apollo astronauts' stance and gait on the Moon. Methods Publicly available National Aeronautics and Space Administration (NASA) footage of astronauts ambulating on the Lunar surface was examined using body pose analysis software. Goniometric lower limb joint/torso angles and width of base of stance and gait were derived. Gait cycle stance phase, swing phase, double support time, and estimated speed of gait were all computed. Results Lunar stance was characterized by 13.3 ± 3.6 SD to 14.3 ± 3.9 SD inch base of stance (based on a 6.5 or 7.0 in. shoe width, respectively), 39.3° ± 9.0° hip flexion, 42.2° ± 14.8° knee flexion, and 17.0° ± 7.5° ankle dorsiflexion. Upper torso anterior tilt was 16.4° ± 8.8°. Lunar gait demonstrated 14.0 ± 2.8 SD to 15.1 ± 2.9 SD base of gait, 0.42 ± 0.16 m/s speed of gait, and 15.4 ± 3.3 in. step length with 40% double support time. Stance phase was 69% and swing phase was 31% of the gait cycle. Discussion Decreased speed of gait with wide base, short steps, and increased double support time was seen in astronaut gait patterns. This pattern is adopted on Earth to increase stability and prevent falls.
Journals
2026 EN
If things are running smoothly in your nonprofits boardroom, it's likely to show up in myriad ways, like strong or improving financials, lower staff turnover and better morale, and clear progress towards organizational mission and impact.
Journals
2026 EN
Most nonprofits find that an annual board self‐assessment not only helps identify strengths and weaknesses that can guide the way towards more effective governance, but they also serve to keep the board engaged in its work in a way that regular board meetings and informal check‐ins do not. These self‐assessments require more focused drill‐downs on what's working and what's not — and how the board, and organization as a whole, is making progress on its mission.
Journals
2026 EN
Canella Marco · BeltranSanz Núria · Gröger Andreas
+17 more
Societal Impact Statement This study underscores the vital role of Alpine botanical gardens (ABGs) in safeguarding Europe's alpine biodiversity amid climate change and habitat loss. By acting as living laboratories and reservoirs of plant genetic resources, ABGs bridge ex situ and in situ conservation, supporting ecosystem resilience and informing restoration strategies. Our findings reveal significant opportunities for ABGs to collaborate with germplasm banks, enhance genetic diversity in collections, and refine propagation protocols. Strengthening these integrative networks not only preserves unique alpine flora but also provides adaptive tools for conservation policies and sustainable land management in mountain regions facing rapid environmental change. Summary The Alps are one of Europe's most diverse ecosystems, but their biodiversity is threatened by climate change, habitat loss, and land‐use changes. Alpine botanical gardens (ABGs) play a crucial role in preserving plant diversity in this region. This study evaluates 14 ABGs across the Alps to assess their effectiveness in preserving the region's flora, with a particular aim to investigate how ABGs can integrate with and strengthen the conservation mission of germplasm banks. We assess representation of alpine flora in the living collections of these 14 ABGs relative to the 5797 taxa of the flora of the Alps, noting cases cultivated at the infraspecific level and examining the overlap of these collections with global germplasm banks. Our findings show that 32% of the 5797 taxa of the flora of the Alps are represented in ABGs, with some species cultivated at the infraspecific level, reflecting both ecological specializations and the expertise of ABG curators. Notably, ABGs contribute significantly to ex situ conservation, although gaps exist in certain taxonomic families and species, especially endemic and policy taxa. Many species in the living collections of ABGs are still missing from global germplasm banks. These findings highlight an opportunity for these gardens to strengthen conservation by contributing seeds and helping to grow species that are difficult to propagate, including narrow endemics. Collaboration with germplasm banks could address existing gaps in genetic diversity, with ABGs acting as field‐based experimental stations to refine propagation techniques. Overall, the importance of ABGs in both ex situ and in situ conservation strategies is underscored, urging stronger collaborations with research facilities and improved propagation protocols to optimize the conservation of alpine plants.