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Navigating diverse human–nature worldviews for more inclusive conservation
No full textDifferent worldviews shape how humans perceive, understand, inhabit, and value the world. Major efforts to achieve more inclusive conservation, such as the Kunming–Montreal Global Biodiversity Framework, seek to more fully reflect diverse worldviews in science, policy, and practice. Building on the Intergovernmental Platform on Biodiversity and Ecosystem Services Values Assessment’s comprehensive review of academic publications, Indigenous and local knowledge sources, and policy documents, we characterize 4 human–nature worldviews: anthropocentrism, biocentrism, ecocentrism, and pluricentrism. This heuristic typology can help conservation scholars and practitioners navigate participatory decision-making by providing conceptual clarity to distinguish particular worldviews and the fuzzy boundaries between them, and by addressing practical issues, particularly discursive and structural power dynamics, that affect worldview expression. Two case studies, protected area prioritization in India and payments for ecosystem services in Colombia, show that inclusive conservation depends on strategies and abilities to recognize and understand diverse worldviews and to articulate them in institutions. These examples highlight that engaging diverse human–nature worldviews applies not only to developing new policies but also to adapting mainstream instruments.</p
Evaluating Bi-Directional Connectionless BLE for Bike-To-Everything Wireless Communications
No full textBike-to-everything (B2X) communication enhances urban safety by enabling real-time information exchange among bicycles, other road users and infrastructure. A key enabler of B2X is Bluetooth Low Energy (BLE), valued for its low power consumption and widespread adoption. While BLE has been well studied for unidirectional communication, two-way discovery, which requires devices to both advertise and scan to achieve mutual awareness in B2X scenarios, remains largely unexplored. Existing models for bi-directional communication assume ideal channel conditions and lack experimental validation, overlooking real-world factors like radio propagation effects and energy consumption. This makes it unclear whether BLE can support timely and energy-efficient message exchange in realistic environments. To address these gaps, we (i) adapt an existing analytical model to capture hardware-specific BLE behaviors and validate it through targeted real-world experiments; (ii) develop and validate a detailed energy consumption model for two-way communication based on BLE hardware measurements; and (iii) define and empirically evaluate new metrics to assess BLE's reliability and timeliness in realistic non-line-of-sight environments. Our findings offer practical guidance for optimizing BLE configurations in real-world B2X deployments
Infill asymptotics for logistic regression estimators for parameters of the intensity function of spatial point processes
No full textThis paper discusses infill asymptotics for logistic regression estimators for spatial point processes whose intensity functions are of log-linear form. First, we establish strong consistency and asymptotic normality for the parameters of a Poisson point process model. We also propose consistent estimators for the asymptotic covariance matrix. Next, we extend the results to general point process models for which replicated realizations are available and, under proper conditions, extend the central limit theorem to estimators from other unbiased estimating equations that are based on the Campbell–Mecke theorem. In a simulation study, we demonstrate the efficiency of a regular dummy point process in logistic regression estimation and pseudo-likelihood estimation. Finally, we demonstrate the approach on data on kitchen fires in the Twente region in the Netherlands
Synergistic enhancement of strength and ductility in Arc-DED Al-Cu alloys via in-situ liquid nitrogen cooling-induced grain structure heterogeneity and porosity suppression
No full textAchieving a favorable strength-ductility balance in heat-treated Al-Cu alloys fabricated by arc-directed energy deposition (Arc-DED) remains challenging due to the difficulty in effective microstructure control and porosity suppression. To address these issues, a synchronized liquid nitrogen cooling (LNC) strategy is introduced during Arc-DED to enhance the strength-ductility synergy of T6-treated Al-Cu components. Compared to the deposits without LNC, LNC-processed samples exhibit a 42 % increase in uniform elongation and a 7.5 % rise in ultimate tensile strength, achieving 482.1 MPa with 10.9 % elongation, outperforming the existing Arc-DED Al-Cu alloys. This improvement results from the coupled effect of 61 % porosity suppression and enhanced grain heterogeneity. Porosity reduction is attributed to a higher cooling rate that promotes hydrogen supersaturation and thereby suppresses hydrogen bubble nucleation during molten pool solidification. Grain heterogeneity arises from reduced peak temperature and the shorter melting duration at the molten-pool bottom, promoting Al3Ti particle retention, increasing nucleation sites and refining equiaxed grains. Further analysis reveals that 69 % of the ductility improvement derives from the hetero-deformation-induced (HDI) strain-hardening, while the remaining 31 % stems from the porosity suppression. Moreover, HDI stress elevates the saturation stress, contributing to the enhanced tensile strength.</p
A generalised superelement formulation for fluid-conveying flexible multibody systems
No full textThis thesis contributes to the development of efficient and versatile modelling techniques for flexible multibody dynamic systems that may include fluid-conveying pipes within the floating frame of reference formulation. Flexible multibody systems are subject to geometric non-linearities due to the large rigid body motion in their components. The floating frame formulation is well suited to such systems, as it separates the gross rigid-body motion from the elastic deformation by introducing a floating frame for each component. Under the assumption of small elastic deformations, well-established model order reduction techniques can be applied at component level. This work expands the capabilities of floating frame of reference-based modelling approaches by addressing key challenges in inertia approximation, in generalisation of reference conditions and reduction methods in floating frame of reference-based superelements, and in integration of fluid-conveying pipe elements.The methods developed in this thesis provide a foundation for analysing systems in which elastic deformations remain small relative to component dimensions, and where inertia effects due to the fluid flow play a significant role while the flow itself can be assumed as inviscid plug flow. The proposed methods offer a practical implementation, because the inertia forces can be computed using solely the consistent finite element mass matrix for elements with both translational and rotational degrees of freedom, supplemented by derivatives along the centreline for fluid-conveying pipes. Moreover, the systems can be modelled using superelements within the global boundary coordinate formulation framework, which is a superelement formulation that supports various reference conditions and reduction bases, enhancing both accuracy and computational efficiency.<br/
Nanobubble nucleation dynamics in reacting microdroplets:Insights from confocal laser scanning microscopy and molecular dynamics simulations
No full textGas-evolving interfacial reactions in microdroplets underpin processes in catalysis, energy conversion, and microreactor technologies, yet the principles of nanobubble nucleation remain unclear. Here, we integrate confocal laser scanning microscopy with coarse-grained molecular dynamics simulations to elucidate hydrogen nanobubble formation during base-catalyzed reactions of liquid organic hydrogen carrier (LOHC) droplets with aqueous NaOH. We reveal a competition-controlled nucleation mechanism governed by gas production rate, asymmetric solubility in droplet and surrounding phases, and water-gas interfacial tension. Nucleation occurs only when local gas concentrations exceed a critical threshold that is largely independent of production rate but strongly influenced by gas solubility in two phases. High production rates shorten induction times and shift nucleation toward the LOHC-water boundary, whereas increased solubility in LOHC or water suppresses nucleation, raising the critical threshold or extracting gas from the droplet. Reduced interfacial tension lowers the nucleation barrier, accelerates onset, and favors interfacial nucleation. These findings establish principles for controlling gas evolution in reactive emulsions, offering design guidelines for interfacial microreactors and nanobubble-enabled catalytic systems.</p
Analyzing and formalising land indicators of LGAF, GLII and SDGs through LADM
No full textOver the past fifteen years, LGAF, GLII, and SDGs frameworks have jointly shaped acomplementary global land governance monitoring system. However, challenges remain indata fragmentation and standardised indicator computation. This study explores how ISO19152 LADM provides a unified technical foundation to model and monitor global landindicators. It develops a standardised conceptual model with UML-based implementation andproposes a modular indicator computation architecture based on interface classes andreusable logic components. The proposed approach supports scalable reporting, enhancesindicator operationalisation, and bridges the gap between global policy frameworks andpractical land administration systems at the national level
Constructing interdisciplinarity, in engineering education and beyond
No full textThis dissertation explores interdisciplinarity as a dynamic, multifaceted process rather than a fixed ideal. Although widely invoked in academic and professional contexts, interdisciplinarity remains ambiguous regarding its meaning and implications. Through interconnected empirical studies in educational settings, this work examines how interdisciplinarity is envisioned, constructed, and enacted, proposing a pluralistic framework for its theoretical understanding and practical application in knowledge work and learning.The first two studies focus on interdisciplinary engineering education (IEE), where interdisciplinarity is often seen as key to addressing complex socio-technical challenges. The first study uses Q methodology to reveal varied perspectives on interdisciplinary competencies, shaped by disciplinary backgrounds, professional orientations, and institutional contexts. The second study investigates how key actors assign meanings to interdisciplinarity, identifying nine interrelated dimensions that reflect its plural nature as a fuzzy constellation of capacities, identities, and institutional practices.The third study shifts to Liberal Arts and Sciences (LAS) education, using ethnographic methods to examine concrete knowledge practices and educational activities. It explores how interdisciplinarity, as an experience, emerges through the interplay between students’ academic identity formation and interpersonal group work. The study uncovers patterns of individual and collective identity, and highlights tensions between exploration and academic legitimacy. It shows that interdisciplinarity in LAS is not simply a curricular feature but is rather continuously negotiated among students, educators, and institutional and social structures.The final chapter synthesizes these insights into a theoretical framework, conceptualizing interdisciplinarity as an evolving process shaped by cognitive, institutional, epistemic, and social dynamics. Rather than a predefined structure or single model, interdisciplinarity is approached as a continual process of construction, negotiation, and reconfiguration. It manifests in diverse forms of interaction and engagement, involving both synchronic and diachronic complexities.Overall, this dissertation challenges essentialist definitions of interdisciplinarity and advances a constructivist, pluralistic approach that embraces its complexity. It offers theoretical insights and practical implications for education and knowledge work, emphasizing the value of adaptable, inclusive, and responsive knowledge environments that support interdisciplinarity’s diverse expressions and evolving nature
Thermo-mechanical Design of Heterogeneous Integrated Wide Bandgap Power Modules
No full textWide bandgap (WBG) semiconductors such as silicon carbide (SiC) and gallium nitride (GaN) offer higher switching speed, greater power density, and elevated operational temperature capabilities compared to silicon-based counterparts. However, conventional packaging technologies cannot fully leverage these benefits, necessitating innovative packaging strategies. This dissertation explores pressure contact technology (PCT) to enhance performance and reliability of highly integrated WBG power modules. Various interconnection approaches are evaluated for their suitability: fuzz buttons provide low parasitic inductance and flexibility for gate connections; graphene film (GF) elastomers offer compact size and high thermal conductivity; and metal sheet springs ensure robust power interconnections. A novel spring connector with low inductance (3 nH) and electrical resistance (5 mΩ) is utilized to connect substrates, enhancing heat dissipation and mechanical stability. The electro-thermal characteristics and reliability of pressure contact with molybdenum plates (PCMo) technology are compared with emerging die-attach technologies such as pressureless sintered Ag (SAg), pressure sintered Cu (PSCu), and commercial TO220 counterparts incorporating the same SiC chips. Experimental results demonstrate that PCMo introduces additional contact resistance (∼ 10 mΩ, 0.42 K/W) but exhibits superior power cycling reliability (∼ 6053 cycles) under a junction temperature from 50ºC to 200ºC due to the elimination of die-attach failures. Failure analysis identifies degradation and crack mechanisms in SAg, PSCu, and TO220 samples. Building on these insights, a 3D PCT-based half-bridge SiC module is developed using GF and fuzz buttons, achieving a low thermal resistance of 0.66 K/W, minimal parasitic inductance of 5.1 nH, and reduced voltage overshoot of 5.8%. For high-power applications, an eight-chip parallel SiC module with metal sheet springs demonstrates balanced current distribution and low inductance of 4.8 nH. The findings of this dissertation highlight the potential of PCT in improving the performance and reliability of heterogeneous integrated WBG power modules, particularly for high-power and high-temperature applications
