Development of Evaluation Indicators for Sports Facilities for People with Disabilities Considering the Universal Design: Focusing on the Republic of Korea

We developed evaluation indicators for sports facilities for people with disabilities and adopted the universal design to conduct Delphi surveys on sports facilities and sports experts. First, the range of universal design element reflection and the method of deriving the evaluation indicators were established through a literature review. Second, 21 experts conducted the first Delphi survey to select the important features of the seven principles of universal design and describe the necessary sub-factors to consider when designing sports facilities. The described elements were divided into 15 categories, and 49 sub-factors were extracted. Third, based on the evaluation of the indicators’ content, acceptance was investigated, and the survey data were analyzed through indicators of reliability and validity of the sub-factors and categories. Fourth, we discussed whether to accept the standard value on the basis of the evaluation index through an expert meeting. Subsequently, the final evaluation index was obtained. The developed evaluation index should be applied by the operators and users of public sports facilities, and validation work is needed. Guidelines for applying the universal design to various sports facilities for people with disabilities should be developed. The financing of sports facilities applying the universal design and related policies should be discussed

Verification of the Mediating Effect of Social Support on Physical Activity and Aging Anxiety of Korean Pre-Older Adults

There is a lack of research on Korean prospective elderly persons. In particular, there is little research regarding whether social support has a mediating effect on the relationship between physical activity and aging anxiety. Accordingly, this study investigated how social support affected physical activity and aging anxiety in 778 prospective senior citizens (55 to 65 years old) out of a total of 1447 senior citizens who participated in the Embrain Panel Power and Panel Marketing Interactive. Participants completed the IPAQ (International Physical Activity Questionnaires), Social Support Scale, and Aging Anxiety Scale. Physical activity in these Korean pre-older adults affected aging anxiety (p < 0.001), with a fixed effect of physical activity on social support (p < 0.001). Further, social support affected aging anxiety (p < 0.001). Social support was also an important parameter in the relationship between physical activity and aging anxiety. In conclusion, high physical activity of pre-older Korean persons lowered their anxiety regarding aging. Social support acted as a mediator that lowered anxiety regarding aging in the most active pre-older persons

Simple Approach to the Highly Efficient and Cost-Effective Inverted Perovskite Solar Cells via Solvent-Engineered Electron-Transporting Layers of Fullerene

With dramatic growth in the photovoltaic (PV) market, perovskite solar cells (PSCs) have achieved remarkable performance and demonstrated enormous potential for use in next-generation PVs. In particular, inverted PSCs have advantages in lowering manufacturing costs because they are suitable for low-temperature printable processability and compatibility with existing silicon PVs for tandem cells. However, for the successful commercialization of PSC-based modules, material cost, a crucial factor, has not been considered in depth. Most inverted PSCs with the highest performance usually consist of fullerene derivatives, which are expensive but difficult to replace with other materials. Therefore, a rational method is needed to solve this problem, and we propose a simple idea to reduce material costs. We systematically investigated the correlation between the properties of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) films and various solvents with different boiling points. We discovered that the highly volatile dichloromethane (DCM) solvent forms a thick and uniform PCBM layer even at quarter concentrations. The DCM–PCBM layer improves the interfacial properties of the PCBM–perovskite film, leading to a device with superior performance compared to that of a device prepared with the PCBM layers from the other solvents. Finally, we successfully demonstrated a high-efficiency inverted PSC based on DCM–PCBM with a maximum power conversion efficiency (PCE) of 22.4%

Highly-Sensitive Resonance-Enhanced Organic Photodetectors for Shortwave Infrared Sensing

Shortwave infrared (SWIR) has various applications, including night vision, remote sensing, and medical imaging. SWIR organic photodetectors (OPDs) offer advantages such as flexibility, cost-effectiveness, and tunable properties, however, lower sensitivity and limited spectral coverage compared to inorganic counterparts are major drawbacks. Here, we propose a simple yet effective and widely applicable strategy to extend the wavelength detection range of OPD to a longer wavelength, using resonant optical microcavity. We demonstrate a proof-of-concept in PTB7-Th:COTIC-4F blend system, achieving external quantum efficiency (EQE) > 50 % over a broad spectrum 450 - 1100 nm with a peak specific detectivity (D*) of 1.1E13 Jones at 1100 nm, while cut-off bandwidth, speed, and linearity are preserved. By employing a novel small-molecule acceptor IR6, a record high EQE = 35 % and D* = 4.1E12 Jones are obtained at 1150 nm. This research emphasizes the importance of optical design in optoelectronic devices, presenting a considerably simpler method to expand the photodetection range compared to a traditional approach that involves developing absorbers with narrow optical gaps

Impact of Thermal Stress on Device Physics and Morphology in Organic Photodetectors

International audienceOrganic photodetectors (OPDs) capable of detecting visible to near-infrared light provide a ubiquitous platform for emerging flexible and wearable electronics. In the process of implementing OPDs into a Si-based manufacturing process, organic semiconductors undergo ≥ 200 °C thermal stress, leading to the deterioration of photosensing capability. Here, we combine multiscale characterization and device physics to unravel the impact of thermal stress on the optoelectronics characteristics of PTB7-Th:non-fullerene acceptor blends (NFAs: SiOTIC-4F, COTIC-4F, CO1-4F, and CO1-4Cl). For as-cast devices, favorable intermixing and phase separation between PTB7-Th and the NFA facilitate charge generation and extraction. Reductions in the OPD performance after thermal annealing (200 °C for 5–120 min) are observed due to the morphological degradation, regardless of the NFA choice, but the reduction is more severe for the PTB7-Th:SiOTIC-4F blend. Thermally induced morphological changes are examined using atomic force microscopy, wide-angle X-ray scattering, and solid-state NMR spectroscopy. This study provides essential insights into morphology-driven deteriorations, which will help in developing structure–stability–performance relationships in high detectivity OPDs

Beyond Molecular Structure: Critically Assessing Machine Learning for Designing Organic Photovoltaic Materials and Devices

Our study explores the current state of machine learning (ML) as applied to predicting and designing organic photovoltaic (OPV) devices. We outline key considerations for selecting the method of encoding a molecular structure and selecting the algorithm while also emphasizing important aspects of training and rigorously evaluating ML models. This work presents the first dataset of OPV device fabrication data mined from the literature. The top models achieve state-of-the-art predictive performance. In particular, we identify an algorithm that is used less frequently, but may be particularly well suited to similar datasets. However, predictive performance remains modest (R2 ≅ 0.6) overall. An in-depth analysis of the dataset attributes this limitation to challenges relating to the size of the dataset, as well as data quality and sparsity. These aspects are directly tied to difficulties imposed by current reporting and publication practices. Advocating for standardized reporting of OPV device fabrication data reporting in publications emerges as crucial to streamline literature mining and foster ML adoption. This comprehensive investigation emphasizes the critical role of both data quantity and quality, and highlights the need for collective efforts to unlock ML\u27s potential to drive advancements in OPV

Resolving Atomic‐Scale Interactions in Nonfullerene Acceptor Organic Solar Cells with Solid‐State NMR Spectroscopy, Crystallographic Modelling, and Molecular Dynamics Simulations

Fused-ring core nonfullerene acceptors (NFAs), designated “Y-series,” have enabled high-performance organic solar cells (OSCs) achieving over 18% power conversion efficiency (PCE). Since the introduction of these NFAs, much effort has been expended to understand the reasons for their exceptional performance. While several studies have identified key optoelectronic properties that govern high PCEs, little is known about the molecular level origins of large variations in performance, spanning from 5% to 18% PCE, for example, in the case of PM6:Y6 OSCs. Here, a combined solid-state NMR, crystallography, and molecular modeling approach to elucidate the atomic-scale interactions in Y6 crystals, thin films, and PM6:Y6 bulk heterojunction (BHJ) blends is introduced. It is shown that the Y6 morphologies in BHJ blends are not governed by the morphology in neat films or single crystals. Notably, PM6:Y6 blends processed from different solvents self-assemble into different structures and morphologies, whereby the relative orientations of the sidechains and end groups of the Y6 molecules to their fused-ring cores play a crucial role in determining the resulting morphology and overall performance of the solar cells. The molecular-level understanding of BHJs enabled by this approach will guide the engineering of next-generation NFAs for stable and efficient OSCs.Office of Naval Research12 month embargo; first published: 24 November 2021This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Additive-free molecular acceptor organic solar cells processed from a biorenewable solvent approaching 15% efficiency

We report on the use of molecular acceptors (MAs) and donor polymers processed with a biomass-derived solvent (2-methyltetrahydrofuran, 2-MeTHF) to facilitate bulk heterojunction (BHJ) organic photovoltaics (OPVs) with power conversion efficiency (PCE) approaching 15%. Our approach makes use of two newly designed donor polymers with an opened ring unit in their structures along with three molecular acceptors (MAs) where the backbone and sidechain were engineered to enhance the processability of BHJ OPVs using 2-MeTHF, as evaluated by an analysis of donor-acceptor (D-A) miscibility and interaction parameters. To understand the differences in the PCE values that ranged from 9-15% as a function of composition, the surface, bulk, and interfacial BHJ morphologies were characterized at different length scales using atomic force microscopy, grazing-incidence wide-angle X-ray scattering, resonant soft X-ray scattering, X-ray photoelectron spectroscopy, and 2D solid-state nuclear magnetic resonance spectroscopy. Our results indicate that the favorable D-A intermixing that occurs in the best performing BHJ film with an average domain size of ∼25 nm, high domain purity, uniform distribution and enhanced local packing interactions - facilitates charge generation and extraction while limiting the trap-assisted recombination process in the device, leading to high effective mobility and good performance.Air Force Office of Scientific Research12 month embargo; first published 05 October 2023This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]