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Metal oxides for Fenton reactions toward radical-assisted water treatment: A review
No full textWater purification is a crucial task in the advancement of human civilization as it plays a significant role in environmental preservation. So far, complex processes and various methods have been utilized to treat contaminated water. Water treatment using radicals via oxidation–reduction is a chemically advanced oxidation process. This reaction is carried out using a metal oxide and a radical precursor. Metals react with oxygen molecules to produce oxides, peroxides, or superoxides. The oxide forms of transition metals have been studied as catalysts and as alternatives to precious metals due to their high stability and low price. This review summarizes recent research activities focused on water treatment using transition metal oxides, bimetallic oxides, and metal oxides doped with co-catalysts.Y
Preferences for Features of Current and Future Residential Environments Among Korean Middle-Aged Adults
No full textThis study examined differences in middle-aged adults' preferred features of their current versus future residential environments and how these differences varied by health and social characteristics. A sample of 1,651 Korean middle-aged adults (aged 49-64) rated their preferences for each of 12 features (e.g., proximity to family/relatives, house price) regarding current and future residential environments, separately. Respondents considered "accessibility to health services" and "opportunity for leisure activities" more important for future residential environments than for current ones. Respondents with poorer health considered features that help them compensate for health decline more important, while those who contacted friends/neighbors more frequently and participated in more cultural activities considered features that help them maintain their social interactions more important for future residential environments than the past. Our findings identified middle-aged adults' various demands for residential features after retirement, which reflect their strategic reactions to future needs for successful adaptation in later years.N
Characterization of particulate matter at Mt. Gwanak (at 632 m) and vertical mixing impacts on haze in Seoul during winter
No full textThis study investigates the sources, chemical composition, and vertical transport of particulate matter (PM) at Mt. Gwanak in southeastern Seoul, focusing on differences between surface and elevated altitudes during winter 2021. Using a time-of-flight aerosol chemical species mass spectrometer (ToF-ACSM), PM was measured at 632 m. At this altitude, PM composition was dominated by organics (41.5 %), nitrate (20.5 %), sulfate (17.8 %), and ammonium (13.6 %). Compared to surface-level measurements, nitrate was lower (27.1 %) at the surface. While organic proportions were similar (41.5 % at 632 m vs. 42.7 % at the surface), oxidized organic aerosols (OOA) were more prominent aloft, as shown by Positive Matrix Factorization (PMF) analysis. Despite no direct anthropogenic sources at 632 m, anthropogenic compounds such as nitrate, primary organic aerosols (POA), and black carbon (BC) were detected, peaking at 13:00 with PBL expansion, suggesting surface-level influence. Two distinct surface haze events were analyzed to understand the influence of upper-layer pollution. The first haze event showed an initial increase in sulfate at high altitudes, which descended to the surface as the PBL expanded. This effect persisted due to the accumulation of nitrate, indicating substantial roles for long-range transport and local accumulation. In contrast, the second haze event was characterized by a marked increase in surface-level NO2, which ascended to higher altitudes and underwent photochemical reactions, resulting in elevated nitrate and O3 levels aloft. These two haze events, coupled with PBL fluctuations demonstrate the complex interactions between atmospheric layers. Therefore, this study highlights the importance of vertical measurements in understanding surface air pollution and haze events. The findings underscores the need for more comprehensive investigations across different seasons and conditions to gain a more complete understanding of these processes.N
Synergistic antibacterial effect of 405 nm blue light-emitting diodes (LEDs) and gelatin film for inactivation of Escherichia coli O157:H7 and Salmonella Typhimurium on stainless steel and fresh fruit peel
No full textA combined antibacterial effect of 405 nm blue LEDs (BL) and gelatin film (G) was investigated on stainless steel (SUS) and fresh fruit peel for the inactivation of Escherichia coli O157:H7 and Salmonella Typhimurium. On the SUS, the sum of the individual treatments of G for 20 min and BL at 20 J/cm2 was <1 log reduction (log CFU/ cm2). In comparison, combination treatment of G and BL (G + BL) at 20 J/cm2 exhibited 2.37 and 3.09 log reduction on E. coli O157:H7 and S. Typhimurium. The G + BL treatment only increased a propidium iodide (PI) uptake, indicating that cell membrane damage occurred. In the G + BL treatment, reactive oxygen species (ROS) scavenging assay confirmed that ROS involved in the bactericidal mechanism. On orange peel, the G + BL treatment at 40 J/cm2 resulted in a 3.05 and 3.17 log reduction on E. coli O157:H7 and S. Typhimurium. In contrast, the individual treatment of G for 40 min led to reductions of 0.63 log CFU/cm2 for E. coli O157:H7 and 0.50 log CFU/cm2 for S. Typhimurium, while the BL treatment at 40 J/cm2 achieved reductions of 0.78 and 0.69 log CFU/cm2, respectively. A synergistic bactericidal effect was similarly observed in the combined treatment groups for both apple and grapefruit peels. In a color and texture analysis, G did not affect hardness, toughness, and visual color of fruit.N
Distilling Diffusion Models Into Conditional GANs
No full textWe propose a method to distill a complex multistep diffusion model into a single-step conditional GAN student model, dramatically accelerating inference, while preserving image quality. Our approach interprets diffusion distillation as a paired image-to-image translation task, using noise-to-image pairs of the diffusion models ODE trajectory. For efficient regression loss computation, we propose E-LatentLPIPS, a perceptual loss operating directly in diffusion models latent space, utilizing an ensemble of augmentations. Furthermore, we adapt a diffusion model to construct a multi-scale discriminator with a text alignment loss to build an effective conditional GAN-based formulation. E-LatentLPIPS converges more efficiently than many existing distillation methods, even accounting for dataset construction costs. We demonstrate that our one-step generator outperforms cutting-edge one-step diffusion distillation models – SDXL-Turbo and SDXL-Lightning – on the COCO benchmark.
A Digital-PLL-Based Quadrature Clock Generator for a Low-Power and Jitter-Filtering-Capable Clock Distribution Scheme in High-Speed DRAM Interfaces
No full textThis article presents a low-power and jitter-filtering-capable clock distribution scheme using a digital phase-locked loop-based (DPLL-based) quadrature clock generator (QCG) for high-speed dynamic random access memory (DRAM) interfaces. The conventional clock distribution distributes four quadrature clock signals at a high frequency of f(CLK )to many DQs over long-distance channels, which consumes significant power. On the contrary, the proposed low-power scheme distributes only a single-phase clock at a much lower frequency, i.e., 1/8 f(CLK ) , so it can reduce the clock distribution power consumption dramatically to 1/32. Then, the proposed QCG generates the precise quadrature clocks with a 25% duty cycle (DC) at f(QCLK) right before DQs. Since the QCG was designed based on a phase-locked loop (PLL) operating at 1/8 f(CLK ) , it can filter the input clock jitter while consuming less than 1-mW power. Since the proposed QCG uses a frequency-independent method to correct the quadrature error, it can extensively increase the operating range of fQCLK . This work also presents the synchronous mode-switching divider (SMS-DIV), enabling an immediate transition between IDLE and ACTIVE modes. The proposed QCG was fabricated in 40-nm CMOS and consumed 900 mu W for generating 2-GHz quadrature output signals. This work achieved a very low quadrature error of less than 0.5 degrees consistently over the frequency range of 1-4 GHz.N
Highly durable and energy-efficient probabilistic bits based on h-BN/SnS2 interface for integer factorization
No full textAs social networks and related data processes have grown exponentially in complexity, the efficient resolution of combinatorial optimization problems has become increasingly crucial. Recent advancements in probabilistic computing approaches have demonstrated significant potential for addressing these problems more efficiently than conventional deterministic computing methods. In this study, we demonstrate a highly durable probabilistic bit (p-bit) device utilizing two-dimensional materials, specifically hexagonal boron nitride (h-BN) and tin disulfide (SnS2 ) nanosheets. By leveraging the inherently stochastic nature of electron trapping and detrapping at the h-BN/SnS2 interface, the device achieves durable probabilistic fluctuations over 108 cycles with minimal energy consumption. To mitigate the static power consumption, we integrated an active switch in series with a p-bit device, replacing conventional resistors. Furthermore, employing the pulse width as the control variable for probabilistic switching significantly enhances noise immunity. We demonstrate the practical application of the proposed p-bit device in implementing invertible Boolean logic gates and subsequent integer factorization, highlighting its potential for solving complex combinatorial optimization problems and extending its applicability to real-world scenarios such as cryptographic systems. imageY
Moment-Aware Video Retrieval for Video Corpus Moment Retrieval
No full textVideo corpus moment retrieval (VCMR) task aims to retrieve a specific moment from a large corpus of untrimmed videos. This task has been addressed by decomposing it into video retrieval and moment retrieval subtasks each with specialized heads (i.e., democratic decomposition), due to the computational complexity. However, this approach overlooks the interdependency between the subtasks, which is crucial for temporally fine-grained query-video alignment. To address this suboptimality, we propose an integrated learning framework that explicitly establishes a connection between the two subtasks, namely moment-aware video retrieval, allowing them to benefit from each other's learning process. Furthermore, we employ a curriculum-based negative sampling strategy that gradually provides harder negative samples to enhance the discriminative ability between semantically similar negative videos. We empirically show that the proposed approach outperforms state-of-the-art methods on three benchmarks - TVR, ActivityNet, and DiDeMo. Notably, on TVR, our method achieves 10.04% in VCMR R@1 with tIoU=0.7, representing a 1.68% absolute improvement over prior work, and similarly demonstrates consistent gains on ActivityNet (4.98% in VCMR R@1 with tIoU=0.5) and DiDeMo, validating the effectiveness of our integrated approach.Y
Strategies to Revitalize Intellectual Property Financing for Food Companies
No full textThis study examines the need for intellectual property (IP) financing for agricultural and food companies and proposes strategies to revitalize this financing model. Recognizing that IP is essential for enhancing corporate value and competitiveness, especially in R&D-intensive food companies, the study identifies key challenges such as limited financing options and high volatility in R&D investment due to financial constraints. By categorizing IP finance into guaranteed loans, collateral loans, and investments, the study evaluates how financial support impacts R&D and company performance. To address existing gaps, the study recommends expanding access to IP financing by diversifying funding channels, including regional and commercial banks, and extending eligibility to cover various IP types, such as utility models, trademarks, and copyrights. Further, given the unique production cycles in agriculture, repayment schedules should align with seasonal cash flows. The study also highlights the need for direct financing methods, such as food crowdfunding, to ease fundraising for smaller firms. Additionally, strengthening IP protection, including technology guarantees and IP insurance, can reduce infringement risks and attract financial institutions. These revitalization measures aim to create a supportive IP finance ecosystem that encourages R&D, supports market competitiveness, and fosters technological advancement in the food sector.N
Quantum yield for sun-induced chlorophyll fluorescence (ΦF) captures rice plant dynamics under interplant competition
No full textPlanting density and leaf angle are important factors related to rice growth and yield through interplant competition. Despite the necessity of understanding the dynamics of interplant competition according to planting density and leaf angle, detailed physiological changes throughout the growth cycle remain less clear due to the requirement for field surveys that are labor-intensive and time-consuming. Sun-induced chlorophyll fluorescence and its physiological quantum yield (Phi(F)) have shown its capability for plant physiological investigations and can provide new opportunities for improved monitoring of crop physiological dynamics. However, it is uncertain whether Phi(F )can quantify the impact of agronomic differences on the vegetative and reproductive growth of crops. In this study, we aim to explore whether Phi(F ) can quantify physiological dynamics in rice of different leaf angle distributions under varying planting density levels. We conducted an experiment of four different planting densities (11.2 x 10(4), 15.2 x 10(4), 18.2 x 10(4), 24.2 x 10(4) hills/ha) with two cultivars of different leaf angle distributions (i.e., erectophile and semi-erectophile leaf angle distribution) in a rice paddy. We measured 'Fand collected agronomic data to monitor plant physiological and structural changes.Phi(F )quantified the down- regulation of photosynthetic activity at higher planting density plots during the vegetative growth period (a significant correlation between Phi(F )and rate of LAI increase, R-2 = 0.62, p-value<0.05) and indicated differences in grain yield, which was dominantly driven by the limited carbon sink (a significant correlation between Phi(F )and yield, R-2 = 0.44, p-value<0.1). Particularly,Phi(F )showed different patterns of the planting density impact on yield between the two cultivars confirming the effect of leaf angle distribution on the interplant competition or the light. Our findings showed that Phi(F )not only captures the difference in vegetative growth but also in reproductive growth and grain yield. This study demonstrated the importance of Phi(F )for physiological investigations in agroecosystems and the potential for estimating crop productivity during the grain-filling stage as well as for improved crop yield estimation.N