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This paper addresses the theme of “the Moral and Ethical Responsibility of Engineers and Engineering”, particularly responding to the question of how to define or deliberate the meaning of ‘public welfare’ and ‘common good’ in engineering degree programs. Drawing from decades of international work on human development, particularly in the global south, this paper reports on adapting the capability approach to an engineering degree program. Developed by Amartya Sen, the capability approach sought to replace GDP-based models of welfare economics by framing the goal of development as enabling individuals to live a life they value. The things a person values, what they are and can do (determined by their opportunities, experiences, and cultural affordances) are their ‘functionings’. In Sen’s framework each individual has a unique ‘functionings vector’ based on what they value. Although someone’s functionings vector indicates valued goals, they will be unsuccessful in achieving their goals unless they have access to needed resources, can effectively utilize those resources, possess agency, and have the ‘capability’ to enact the functionings. ‘Capabilities’ determine the set of functionings that are actually available to a person. Although rarely used in engineering, the capability approach offers a mature and well-developed framework to address issues of public welfare. Public good is defined through an individual’s freedom to pursue a life they have reason to value, and such freedom defines both the means and end of development. The role of engineering in society—primarily through development of infrastructure—is to support equitable access to capabilities for all individuals. Through support of an NSF Revolutionizing Engineering Departments (RED) grant, an ECE department in a mid-Atlantic liberal arts university has adapted the capability approach to inform change in an undergraduate degree program. Specific examples from four years of implementation are shared. 

In this work, a tung oil-based thermosetting resin was synthesized via free radical polymerization and reinforced with thirteen different types of sand. The viability of this process inspired the adaptation of the resin for its use as a binder material in binder jetting, an additive manufacturing process. Firstly, it was shown that the resin could have its initial viscosity (~0.33 cP) increased upon heating to attain values compatible to existing printing systems. The curing kinetics of the resin was assessed via dielectric analysis (DEA), combining the utilization of heat and ultraviolet (UV) light, showing that a resin with a viscosity of 10 cP can be fully cured after 250 min at 90 ◦C, or 300 min at 75 ◦C, both under a 365 nm light exposure. Preliminary binder-jet tests successfully provided a solid object, which was post-cured, resulting in a hard specimen. The results presented herein suggest that the tung oil-based resin in question is a suitable bio-based binder for binder-jet 3D-printing applications. The novelty of the work reported lies in the conversion of an already established and effective bio-based thermosetting resin into a versatile photocurable binder that can be irrestrictively used with unsorted sands of different composition, making this technology broadly applicable to different isolated regions, using local resources available. The technology presented herein is potentially transformative and impactful, as binder jetting is typically associated to extremely well-sorted particles. 

Context: As faculty of engineering degree programs in private liberal-arts universities in the United States the authors are structurally insulated from many immediate crises, but at the leading edge of other, more slowly evolving ones. These slow-motion crises are occurring in the education systems of many developing countries and can be classified as crises of economics, related to the cost and received value of a degree; crises of equity from ongoing and systemic disparities in educational outcomes; and crises of organization arising from contested visions of the purpose of higher education. While lacking the urgency of current water, food, energy, and climate crises, they are no less important since education is both a core capability and functioning for living a life one values. Methodology: To address these persistent and systemic issues this paper reports on an ongoing conceptual reorganization of a degree program using the capability approach. The reorganization entails shifting from the dominant outcomes-based paradigm of engineering education in the United States to an opportunity-based framework that prioritizes student development over human capital. We report on efforts over a two-year time frame to adapt the capability approach to the degree programs in a single engineering department. While much of the application of the capability approach in education has focused on the systemic or macro-scale, in this work we have adopted an ecological metaphor to work across scales, drawing from prior macro-scale work to inform change efforts at micro-scale of a single degree program. Several parallel efforts were required to align the program to a more capability informed model. One was to identify and articulate sets of capabilities across educational scales for a variety of stakeholders, following processes recommended by established capabilities scholars (Robeyns 2017, Walker 2008, Mathebula 2018). A set of potential capabilities were developed by drawing from multiple internal and external influencers of the program. These lists were then iteratively refined based on faculty feedback, ethnographic observations, and case studies before being vetted by student stakeholders using a Q-method approach (Simpson 2018). Another was to find ways to directly engage students with the capabilities-driven transformation structural changes to the curriculum were implemented to elicit reflection. Finally, to ground these efforts in prior student developmental work in engineering education, we revised a model of the capabilities approach that integrates social cognitive career theory (SCCT) (Lent et al. 2002). This model integrated existing educational outcomes with capabilities and functionings, explicating their relationships. The model also emphasized various pedagogical processes used in the degree program and connected them to student development in engineering using social cognitive career theory. Data collection involved modifications to previously validated instruments. Analysis: These development efforts are at a stage where data is still emerging, but have shown the viability of a capability approach as a tool for reconsideration of processes and mission of degree programs. As in other domains where the capability approach has been applied, many of the results emerge from the process itself as normative questions are fore fronted and addressed in a democratic fashion. As a case study in micro-scale application of the capability approach, this paper shows the viability of this framework to engender and assess the highly multidimensional effects the capability approach can have on student learning and well-being in higher education degree programs. This case study discusses ongoing reorganization of a degree program from an outcomes-based paradigm to an opportunity-based framework using the capability approach. Preliminary results show the capability approach is a viable framework for normative reconsideration of processes and missions of degree programs. This works informs use of the capability approach in a localized, small-scale implementation within higher education in the Unites States. 

In binder jet additive manufacturing (BJAM), uniformity and density of the powder layer impact green part quality. This study investigates the printability of unrefined sand using counter-roller spreading. Altair EDEM, a high-performance software powered by the Discrete Element Method (DEM), was used to simulate the BJAM process to evaluate powder bed homogeneity and density under various operating conditions, including roller rotational speed, traverse speed, powder layer thickness, and roller diameter. Utilizing high-performance computing (HPC) and graphics processing unit (GPU) clusters, time-efficient, and more realistic, simulations were performed simulating 300,000 grains. Detailed DEM simulations were executed by reconstructing representative particle shapes using two-dimensional images obtained using particle characterization equipment. The results highlight roller velocity and powder layer thickness as key determinants of sand spreadability. Optimal powder bed density (PBD) was achieved at a roller velocity of 20 mm/s with minimal deviation. A layer thickness exceeding 200 micrometers was found to prevent jamming and void formation, while percolation led to size segregation. The findings indicate that producing uniform and dense layers of unrefined sand is feasible but may incur trade-offs in print resolution and increased printing times. This work contributes to the advancement of sustainable and/or remote BJAM technologies, ensuring progress in both environmental sustainability and accessibility. 

Super resolution microscopy was developed to overcome the Abbe diffraction limit, which effects conventional optical microscopy, in order to study the smaller components of biological systems. In recent years nanomaterials have been explored as luminescent probes for super resolution microscopy, as many have advantages over traditional fluorescent dye molecules. This review will summarize several different types of nanomaterial probes, covering quantum dots, carbon dots, and dye doped nanoparticles. For the purposes of this review the term “nanoparticle” will be limited to polymer-based, protein-based, and silica-based nanoparticles, including core–shell structured nanoparticles. Luminescent nanomaterials have shown promise as super-resolution probes, and continued research in this area will yield new advances in both materials science and biochemical microscopy at the nanometer scale. 

Distributed manipulators - consisting of a set of actuators or robots working cooperatively to achieve a manipulation task - are robust and flexible tools for performing a range of planar manipulation skills. One novel example is the delta array, a distributed manipulator composed of a grid of delta robots, capable of performing dexterous manipulation tasks using strategies incorporating both dynamic and static contact. Hand-designing effective distributed control policies for such a manipulator can be complex and time consuming, given the high-dimensional action space and unfamiliar system dynamics. In this paper, we examine the principles guiding development and control of such a delta array for a planar translation task. We explore policy learning as a robust cooperative control approach, allowing for smooth manipulation of a range of objects, showing improved accuracy and efficiency over baseline human-designed policies. 

Context.Small planets transiting bright nearby stars are essential to our understanding of the formation and evolution of exoplanetary systems. However, few constitute prime targets for atmospheric characterization, and even fewer are part of multiple star systems. Aims.This work aims to validate TOI-4336 A b, a sub-Neptune-sized exoplanet candidate identified by the TESS space-based transit survey around a nearby M dwarf. Methods.We validated the planetary nature of TOI-4336 A b through the global analysis of TESS and follow-up multi-band high-precision photometric data from ground-based telescopes, medium- and high-resolution spectroscopy of the host star, high-resolution speckle imaging, and archival images. Results.The newly discovered exoplanet TOI-4336 A b has a radius of 2.1 ± 0.1R_⊕. Its host star is an M3.5-dwarf star with a mass of 0.33 ± 0.01M_⊙and a radius of 0.33 ± 0.02R_⊙, and is a member of a hierarchical triple M-dwarf system 22 pc away from the Sun. The planet’s orbital period of 16.3 days places it at the inner edge of the habitable zone of its host star, which is the brightest of the inner binary pair. The parameters of the system make TOI-4336 A b an extremely promising target for the detailed atmospheric characterization of a temperate sub-Neptune by transit transmission spectroscopy with JWST. 

Abstract In drylands, runoff during storms redistributes water and nutrients from bare soil areas to vegetated patches, subsidizing vegetation with additional resources. The extent of this redistribution depends on the interplay between surface roughness and permeability; greater permeability in vegetated patches promotes run‐on to vegetation, but greater surface roughness diverts runoff, producing tortuous flow paths that bypass vegetation. Here, this interplay is examined in virtual experiments using the 2D Saint Venant Equations to measure runoff connectivity. Flowpaths are delineated using tracers advected by the flow. Distances between tracer sources and sinks along flowpaths measure hydrologic connectivity at two lengthscales: connectivity to the hillslope outlet and within‐slope source‐sink connectivity. Differences between these connectivity lengthscales indicate how flow may “by‐pass” vegetated patches within hillslopes. At the hillslope scale, a derived power‐law relation between the runoff coefficient and outlet connectivity describes hillslope water losses, providing a foundation for identifying landscapes likely to shed water.