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Abstract This study optimizes VT and ΔVT in amorphous indium-gallium-zinc-oxide (a-IGZO) field-effect transistors (FETs) by examining the influence of both channel length (L) and Ga composition. It was observed that as the ratio of In: Ga: Zn changed from 1:1:1 to 0.307:0.39:0.303 in the IGZO film, both VT and ΔVT decreased by 0.1 V at the shortest channel length (L = 0.5 μm). This reduction was attributed to the change in the oxygen concentration in IGZO due to the variation in Ga composition. In addition, as the channel length decreased from 10 μm to 0.5 μm, VT decreased by up to 0.7 V, and ΔVT decreased by up to 0.4 V. This observation was due to diffusion of oxygen vacancies (VO) from the source and drain into the main channel. To provide a comprehensive understanding, we quantitatively modeled the doping concentration of IGZO and the trap density of gate insulator (GI) traps using TCAD simulation based on Ga composition and diffusion of VO. Using this approach, we propose a method to optimize the design of a-IGZO FETs with high VT and low ΔVT in short-channel devices by adjusting the Ga composition.

OBJECTIVES To assess social inequalities in changes in dietary behaviors among adolescents during the coronavirus disease 2019 (COVID-19) pandemic, we compared changes in dietary behavior indicators by household income. METHODS Using cross-sectional data from the 2019 and 2020 Korea National Health and Nutrition Examination Survey, the prevalence of dietary behaviors in adolescents (12–18 years old) was estimated and changes in dietary behaviors during the COVID-19 pandemic were evaluated. We assessed changes in dietary behaviors with a household income (as a measure of socioeconomic status, SES) disparity. RESULTS During the COVID-19 pandemic, the average consumption of vegetables decreased and food insecurity worsened. Adolescents were more likely to skip breakfast than before COVID-19 (33.1 and 37.4%). Soft drink consumption also increased in 2020 from 2019 (7.6 and 14.8%), especially among boys. Average sugar intake and sodium intake showed a tendency to decrease only in girls, but there was no significant difference according to SES level. Skipping breakfast was particularly evident in the low-SES group, and the difference according to household income level (high vs. low) was greater during COVID-19 than before. The prevalence of soft drink consumption increased significantly in the low-SES group, but the rate of increase did not differ by SES level. CONCLUSIONS We found that the social disparity in skipping breakfast was further aggravated during the COVID-19 pandemic. To reach a better understanding of the dietary behaviors of adolescents, continuous monitoring is necessary.

Why, how, and when can logos with a blue positive space communicate competence versus sadness? Why, how, and when might logos with a red positive space evoke impressions of liveliness versus aggressiveness? As the current research establishes, a black background strengthens the negative meanings associated with the hue of a logo's positive space and weakens its positive meanings. Conversely, a white background strengthens its positive meanings and weakens its negative meanings. These automatic effects occur because the hue of the positive space interacts with the color of the negative space to determine whether logos communicate positive or negative brand impressions more vividly. These effects are broadly applicable to both well-known and unknown brands, yet they are attenuated for meaningful logos and filled-frame logos. With these novel findings, this article identifies specific factors that can alter the meanings of logo hues, provides a theoretical lens for understanding the interplay of the background color and the hue of the positive space, and offers guidelines for crafting effective logos. This article also reveals which brands can benefit most from conveying negative impressions through their logos: logos with a black (white) background enhance evaluations of brands that possess negatively (positively) valenced personality traits. [ABSTRACT FROM AUTHOR]

Optimizing alloy composition is an effective way to improve the microstructure and properties of superalloys. Herein, the influence of carbon content (0.071, 0.105, and 0.136 wt%, respectively) on the microstructure and mechanical properties of GH3230 alloy formed by laser melting deposition is investigated. The results indicate that the carbon contents affect the quantity, morphology, and distribution of carbides in the matrix of the alloy. As the carbon content increases, the number of carbides increases, and the morphology of the carbides at the grain boundaries changes from discontinuous blocks to chains, and finally into strips. Three alloys with high plasticity at room temperature, and the maximum elongation close to 60% is achieved for alloy containing 0.105 wt% C. The high‐temperature elongation of the alloy also increases at first and then decreases with the carbon. It is therefore concludes that the optimized carbon content is 0.105 wt% by combining both the strength and plasticity for GH3230 alloy prepared by laser melting deposition. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide (S-CO2) has the advantages of amphoteric liquid and gas, which possesses many unique characteristics, such as good compressibility, high density, high solubility, good fluidity and low viscosity. The Brayton cycle with S-CO2 is considered to have many promising applications, especially for power conversion industries. However, the corrosion and degradation of structural materials hinder the development and application of the Brayton cycle with S-CO2. Nickel-based alloys have the best corrosion resistance in S-CO2 environments compared to austenitic stainless steels and ferritic/martensitic steels. Thus, the present article mainly reviews the corrosion behaviour of nickel-based alloys in S-CO2 under high temperature and pressure. The effect of alloying elements and environment parameters on the corrosion behaviour of different nickel-based alloys are systematically summarized. The conclusion and outlook are given at the end. [ABSTRACT FROM AUTHOR]