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Design Education 4.0: Technology-driven design futures & the future of design education
No full textDesign education has always strived to equip future designers the knowledge, skills, and expertise to work at the intersection of applied technology and the people who use it. The difference for contemporary design is the accelerating pace of technological change. Where previous generations expected to use the same core technology throughout their lifetime, users now and into the future will experience significant change within a generation. We report a project aimed at understanding how design education must change to leverage the opportunity of technology-driven design futures. In an international, collaborative project on the future of design education, we report a comparative audit of education provision at one Korean and one UK-based design school, both located within colleges of engineering at their respective institutions. We also report insights derived from a workshop activity (Design Sprint). During the workshop, faculty and students form the two institutions, together with associated project partners, attempted to address design problems around sustainable futures: with focus upon technology-driven solutions. We finally report some initial insights and recommendations towards the skills and expertise required of the future designer
Entropy analysis and hydrothermal behavior of magnetohydrodynamic MOS2???Fe3O4/H2O hybrid nanofluid flow driven by buoyancy in a square enclosure with diverse fin heights
No full textFins, referred to as extended surfaces, play a crucial role in enhancing heat transfer across various industrial sectors. They achieve this by increasing the surface area available for convective heat transfer. These widespread applications span fields such as energy production, mechanical engineering, surface studies, heat recovery processes, and chemical engineering. The broad utility of fins has prompted researchers to enhance their precision through diverse methods, including numerical, experimental, and analytical approaches. Motivated by these practical applications, this study undertakes a theoretical investigation to analyze the effects of varying fin heights on the behavior of a hybrid hydromagnetic nanofluid within a porous square enclosure. The study explores three distinct cases. In the first case, fixed-height heat fins are attached to the upper and lower walls. In the second case, the fin attached to the upper wall remains static, while those on the lower wall are extended from 0.25L to 0.5L. Conversely, the third case involves extending the height of the upper fin from 0.25L to 0.5L. The in-house MATLAB code, coupled with a finite difference method, is employed to solve the governing equations, and its reliability is confirmed through comparison with prior publications. Thorough numerical simulations are conducted, encompassing control parameters such as thermal radiation, Rayleigh number, nanoparticle volume fraction, Hartmann number, heat generation/absorption, and Darcy number. The numerical results are visually presented through streamlines, isotherms, and average Nusselt number plots, elucidating the impact of these parameters across a range of scenarios. It is noticed that case 3 exposes a 96.06% higher heat transfer rate than case 2 with higher values of volume fraction and Rayleigh number. In all three cases, the Rayleigh number and Hartmann number cause a reduction in the entropy generation. For a higher Rayleigh number, employing a hybrid nanofluid containing a volume fraction of 5% causes a 110.41% reduction in heat transfer for the case involving bottom fin height compared to case 1. Similarly, extending the top fin leads to a heat transfer reduction of 100.41%
National climate change governance and lock-in: Insights from Korea's conservative and liberal governments' committees
No full textWhen establishing national climate change response policies, conflicts between various stakeholders may arise. Therefore, we need a collaborative climate change governance to coordinate stakeholders' opinions. Many countries have formed and operated committee-type governance to respond to climate change. Climate change policies require long-term responses. However, the politicization of climate change issues results in rapid policy changes and policy discontinuities. In Korea, climate change policies are showing differences according to partisan polarization. Past conservative and liberal governments formed committees to respond to climate change. Conservative governments operated the Green Growth Committee, and liberal governments operated the Carbon Neutrality Committee. This study analyzed the impact of changes in the Korean political system on climate change governance. We examined whether the difference in political orientation between liberal and conservative governments affected climate change governance, and if not, what factors prevented the path from changing. No significantly different outcome was found between the governance of the conservative and the liberal governments in response to climate change. The cause was the "lock-in" of climate change policies in Korea. Specifically, the response to climate change in Korea has not changed significantly due to political, in-dustrial, institutional, and diplomatic lock-in
Silver sulfide nanocrystals as a biocompatible and full-spectrum photocatalyst for efficient light-driven polymerization under aqueous and ambient conditions
No full textOwing to current global environmental concerns, polymers must be prepared under eco-friendly reaction conditions based on sustainable chemistry. In this context, highly efficient photoinduced energy/electron transfer reversible addition???fragmentation chain-transfer (PET-RAFT) polymerization under ambient/aqueous conditions without additives and/or with the aid of sunlight is the optimal approach for producing polymers with well-defined structures. This can be accomplished with a photocatalyst (PC) that utilizes the full spectrum of sunlight for maximum efficiency and has excellent water solubility or dispersibility, oxygen tolerance, and biocompatibility. However, a PC with all of these features has not yet been developed. In this study, we confirmed that this could be achieved using Ag2S nanocrystals (NCs) as photocatalysts. The sufficient reducing power of Ag2S NCs enabled the successful aqueous PET-RAFT polymerization of numerous acrylic monomers under ambient natural sunlight illumination without any additives. Under illumination, the small band gap of Ag2S NCs suppressed the generation of singlet oxygen, resulting in low cytotoxicity toward three different cell lines. Finally, we demonstrated that PET-RAFT polymerization with Ag2S NCs can be accomplished in biologically relevant media under natural sunlight illumination, indicating adequate biocompatibility and efficacy of the system
Bio-inspired mononuclear nonheme metal peroxo complexes: Synthesis, structures and mechanistic studies toward understanding enzymatic reactions
No full textMetalloenzymes utilize inexpensive and earth-abundant transition metal ions as important co-factors to enable binding of a dioxygen molecule so that it can be used in various biological metabolisms. For many important enzymatic reactions, dioxygen binding and activation is the fundamental process used to gen-erate chemically reactive metal-oxygen intermediates. During past decades, a variety of hypothetical metal-oxygen adducts have been proposed as key intermediates in the catalytic reaction of metalloen-zymes. For example, metal peroxo species have been considered and sometimes directly captured spec-troscopically and crystallographically at the active site of several metalloenzymes including Rieske dioxygenase, deformylase and superoxide dismutase. To understand the chemical properties and reactiv-ities of the metal peroxo intermediates, synthetic model chemistry has been advanced with numerous ligand systems and central metal ions. The successful synthesis of well-characterized metal peroxo com-pounds has allowed us to acquire deep insights into the mechanisms of such enzymatic reactions. In this review, we encompass overall studies on the nonheme first-row transition metal peroxo complexes (M = Mn, Fe, Co, Ni and Cu) with physicochemical characterization and structural information. The chem-ical reactivities of the metal peroxo complexes relevant to the biological system are also presented. Nucleophilic aldehyde deformylation has become a representative reaction mediated by the metal peroxo intermediates, and recent findings have revealed unique reaction mechanisms such as nitrile activation. Furthermore, rate-determining H atom abstraction has also been suggested in the current study on the aldehyde deformylation. Extrinsic factors to control the chemical properties and reactivities of the metal peroxo complexes have recently been accomplished through adding the redox inactive metal ion and modifying the ligand topology. It is hoped that the comprehensive knowledge presented in this review will help to broaden and deepen our understanding of the metal peroxo intermediates and be useful to understand enzyme mechanisms and to develop bioinspired catalysts.(c) 2023 Elsevier B.V. All rights reserved
Persistent impacts of smoking on resting-state EEG in male chronic smokers and past-smokers with 20 years of abstinence
No full textThis work was supported in part by UNIST internal funding (1.210046.01) and the National Research Foundation of Korea (NRF-2018R1D1A1B07043582 to Chung). K.B. was partly supported by the National Research Foundation of Korea (NRF-2021R1F1A1063968), Institute of Information & Communications Technology Planning & Evaluation (Grant No. 2020-0-01450, Artificial Intelligence Convergence Research Center [Pusan National University]), and Ministry of Education of South Korea (the BK21 Four program, Korean Southeast Center for the 4th Industrial Revolution Leader Education)
Strong evidence for ideomotor theory: Unwilled manifestation of the conceptual attribute in movement control
No full textScientific understanding of how the mind generates bodily actions remains opaque. In the early 19th century, the ideomotor theory proposed that humans generate voluntary actions by imagining the sensory consequence of those actions, implying that the idea of an action???s consequence mediates between the intention to act and motor control. Despite its long history and theoretical importance, existing empirical evidence for the ideomotor theory is not strong enough to rule out alternative hypotheses. In this study, we devised a categorization-action task to evaluate ideomotor theory by testing whether an idea, distinguished from a stimulus, can modulate task-irrelevant movements. In Experiment 1, participants categorized a stimulus duration as long or short by pressing an assigned key. The results show that participants pressed the key longer when categorizing the stimulus as long than they did when characterizing it as short. In Experiment 2, we showed that the keypressing durations were not modulated by the decision category when the property of the decision category, the brightness of a stimulus, was not easily transferable to the action. In summary, our results suggest that while the perceived stimulus features have a marginal effect on response duration linearly, the decision category is the main factor affecting the response duration. Our results indicate that an abstract category attribute can strongly modulate action execution, constraining theoretical conjectures about the ideomotor account of how people voluntarily generate action
Merging Platinum Single Atoms to Achieve Ultrahigh Mass Activity and Low Hydrogen Production Cost
No full textSingle atom catalysts (SACs) with isolated active sites exhibit the highest reported mass activity for hydrogen evolution catalysis, which is crucial for practical applications. Here, we demonstrate that ultrahigh mass activity can also be achieved by rationally merging the isolated platinum (Pt) active sites in SAC. The catalyst was obtained by the thermodynamically driven diffusing and merging phosphorus-doped carbon (PC) supported Pt single atoms (Pt1@PC) into Pt nanoclusters (PtM@PC). X-ray absorption spectroscopy analysis revealed that the merged nanoclusters exhibit much stronger interactions with the support than the traditional method, enabling more efficient electron transfer. The optimized PtM@PC exhibited an order of magnitude higher mass activity (12.7 A mgPt-1) than Pt1@PC (0.9 A mgPt-1) at an overpotential of 10 mV in acidic media, which is the highest record to date, far exceeding reports for other outstanding SACs. Theoretical study revealed that the collective active sites in PtM@PC exhibit both favorable hydrogen binding energy and fast reaction kinetics, leading to the significantly enhanced mass activity. Despite its low Pt content (2.2 wt %), a low hydrogen production cost of similar to 3 USD kg-1 was finally achieved in the full-water splitting at a laboratory scale