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Comprehensive crosslinking strategy using fluorinated azide to enhance the thermal stability of ceramic-coated separators for Li-ion batteries
No full textEnhancing the thermal and mechanical stabilities of ceramic-coated separators (CCSs) is required for high-safety lithium-ion batteries (LIBs). As both the thickness and areal mass of ceramic coating layers (CCLs) have reduced, various strategies have been developed to overcome the limitations of conventional ceramics and polymeric binders. In this regard, we suggest a comprehensive photocrosslinking approach to form fully crosslinked CCLs using a new fluorinated azide binder that can readily react with aliphatic functional groups in any component of CCSs. When a small amount of azide binder is added to a CCL slurry consisting of Al2O3 particles and a poly(acrylic acid) (PAA) binder, short UV irradiation can lead to inter- and intramolecular crosslinking points within the polyethylene (PE) separator, between the PE separator and the PAA binder, and within the PAA binders in the CCL. Consequently, the thermal stability and the adhesive strength of crosslinked CCS (X-CCS) can be significantly improved compared to the control CCS without azide. Moreover, a LiNi0.6Co0.2Mn0.2O2/graphite cell with X-CCS exhibited a comparable cycle life to that of the PE separator and non-crosslinked CCS. Furthermore, because UV illuminators are easily added to conventional fabrication processes, this strategy is a simple but effective approach for advancing high-safety LIBs. © 2024 Elsevier B.V.FALSEsciescopu
The Chief Business of the True Judges in Hume’s Standard of Taste
No full textIn his essay ‘Of the Standard of Taste’, Hume identifies two standards of taste: the general rules of art and the joint verdict of true judges. From this the following questions arise: Why did Hume present two standards? And, how should we understand the relation between them? We must first get a firmer grasp on each of the standards that Hume presents. Hence, this paper has two main goals. The first is to understand the general rules of art in the light of Hume’s philosophical method, which is consonant with Newtonian methods of analysis and synthesis. The second is to provide a new interpretation of what Hume takes to be the joint verdict of true judges. In my interpretation, the joint verdict of true judges constitutes the standard of taste, not because their verdicts converge, but because their verdicts encompass blameless differences. With this new foundation for understanding the two standards, I will present my own reading of the relation between them. © British Society of Aesthetics 2024. Published by Oxford University Press on behalf of the British Society of Aesthetics. All rights reserved.FALSEahciscopu
The In vitro reconstituted the lens-specific intermediate filament with filensin and phakinin replicates the genotype-phenotype correlation for cataracts
No full textThe intermediate filaments (IFs) family is one of the cyto-skeletons that regulate cell shape, size, stiffness, and movement. Unlike other cytoskeletons such as actin and tubulin, alpha-helical linear proteins of the IFs family constitute filament formation, which can be classified in six types depending on their assembly mechanisms. Filensin and phakinin, which are classified into the type-VI IFs, are only expressed in lens fiber cells and are composed of the lens-specific IFs. However, it is unclear how filensin and phakinin constitute filaments and have an impact on lens properties. Here, we studied the in vitro molecular assembly of human filensin and phakinin to identify the structural and functional relationships. We reconstituted the co-assembled filaments with human recombinant filensin and phakinin and determined its stoichiometry as the ratio of one-to-one. Filensin and phakinin filaments interacted with alpha-crystallin and assembled to make a beeded structure detected by the sedimentation assay and TEM. Moreover, the cataract disease mutant phakinin E233del caused short filaments and reduced resistance against heat and shear stress. We further showed that the alpha-helical rod domains in each protein are involved in the interaction between two proteins, and the intrinsically disordered head and tail domains regulates filament extension. Overall, we determined the molecular interaction in the lens-IFs, which confers the crystalline lens with stability against physical stress. These results suggest that the impaired integrity of the IF can lead to age-related diseases like cataracts and presbyopia
Area Optimization of the Feed-Forward Equalizer for ADC-Based High-Speed Wireline Receiver Using Channel Characteristics
No full textIn high-speed serial link, the analog-digital converter (ADC)-based receiver (RX) architecture has been widely applied with 4-level pulse amplitude modulation (PAM-4) for> 56 Gb/s/lane. While ADC-based RXs exhibit strong equalization capability, the feed-forward equalizer (FFE) in its digital signal processor (DSP) occupies a large area due to the large number of multipliers required to implement the parallel finite impulse response (FIR) filter. In this work, we explore the required number of bits for the FFE coefficients depending on the tap position given a chip-to-chip channel profile. By proper bit-level optimization of the FFE multipliers, 42 % of the FFE area could be saved for the twelve largest FFE tap values as compared to the case where the same-sized FFE multipliers are considered for a channel exhibiting 28 dB of loss at 28 GHz. © 2024 IEEE
Efficacy of robot arm-assisted endoscopic submucosal dissection in live porcine stomach (with video)
Get PDFEndoscopic submucosal dissection (ESD) is technically challenging and requires a high level of skill. However, there is no effective method of exposing the submucosal plane during dissection. In this study, the efficacy of robot arm-assisted tissue traction for gastric ESD was evaluated using an in vivo porcine model. The stomach of each pig was divided into eight locations. In the conventional ESD (C-ESD) group, one ESD was performed at each location (N = 8). In the robot arm-assisted ESD (R-ESD) group, two ESDs were performed at each location (N = 16). The primary endpoint was the submucosal dissection speed (mm2/s). The robot arm could apply tissue traction in the desired direction and successfully expose the submucosal plane during submucosal dissection in all lesion locations. The submucosal dissection speed was significantly faster in the R-ESD group than in the C-ESD group (p = 0.005). The blind dissection rate was significantly lower in the R-ESD group (P = 0.000). The robotic arm-assisted traction in ESD enabled a significant improvement in submucosal dissection speed, blind dissection rate which suggests the potential for making ESD easier and enhancing procedural efficiency and safety. © The Author(s) 2024.TRUEsciescopu
할로겐화납 페로브스카이트 전구체와의 시너지 효과 강화를 통한 안정화 및 패시베이션 전략의 통합적 연구
No full textperovskite solar cells, stabilizer, hydrogen bond, precursor결함이 낮은 고품질 페로브스카이트 층은 고효율 태양 전지를 발전시키는 데 매우 중요합니다. 그러나 몇 가지 문제는 특히 유기 양이온 및 요오드 이온과 같은 주요 문제가 있는 불안정성을 남기는 페로브스카이트 잉크로 인해 재현성을 갖춘 지속 가능한 페로브스카이트 태양전지를 향한 몇 가지 과제를 여전히 제기합니다. 페로브스카이트 전구체를 안정화하기 위해 우선적으로 처리하는 주요 사항을 설명합니다. 저희의 전략은 포름아미디늄 이온 (FA+)인 주요 유기 양이온과의 강화된 수소결합에 초점을 맞추고 FA+와 탈양성화된 메틸 아민 (MA) 사이의 비가역적 반응을 크게 억제합니다. 이러한 문제를 해결하기 위해서 3-메르캅토벤조산 (3-MBA)을 첨가제로 도입하는 전략을 고안했습니다. 그 결과 페로브스카이트 잉크는 최대 140일 동안 초기 효율의 96% 이상을 유지했습니다. 마찬가지로 중요한 것으로, 페로브스카이트 층에서 생성된 많은 결함이 3-MBA의 배위 시스템에 의해 부동태화된다는 것입니다. 따라서 페로브스카이트 전구체 잉크와 필름을 모두 관리하는 통합 전략을 강조합니다. 3-MBA 첨가제가 포함된 역 구조 페로브스카이트 태양 전지는 24.31%의 인상적인 효율을 나타내며 30 ± 5%의 RH에 노출된 후에도 초기 효율의 96% 이상을 유지합니다.|A high-quality perovskite layer with low defects is critical for advancing high-efficiency solar cells. However, a few issues still pose several challenges toward sustainable PSCs with reproducibility, particularly, due to perovskite inks, which leave major problematic instability such as organic cations and iodide ions. Here, we unravel major points that preferentially deal with to stabilize the perovskite precursors. Our strategy focuses on the strengthened hydrogen bonding with the major organic cation which is formamidinium ion (FA+), significantly inhibits irreversible reaction between FA+ and deprotonated methylamine (MA). To address these issues, we devised a strategy to introduce 3-mercaptobenzoic acid (3-MBA) as an additive. Consequently, perovskite inks maintained more than 96% of initial PCE for up to 140d. Equally important, a number of defects created in the perovskite layer are passivated by the coordination system of 3-MBA. Thereby, we highlight the integrated strategy to manage both perovskite precursor inks and films. The inverted PSCs with 3-MBA additive exhibit an impressive PCE of 24.31% and maintain over 96% of their initial PCE even after exposure to RH of 30 ± 5%.List of Contents
Abstract i
List of contents ii
List of tables iii
List of figures vi
Ⅰ. Introduction 1
1.1 Emerging perovskite solar cells with overcoming their structural instability 1
1.2 Instability of the perovskite precursors 1
1.3 The integrated strategy to regulate perovskite precursors and films 2
Ⅱ. Experimental 4
2.1 materials 4
2.2 The preparation of perovskite solutions 4
2.3 The preparation of anodized nickel oxide (A-NiO) 4
2.4 Device fabrication 5
2.5 Characterization of perovskite film and devices 6
2.5.1 Note 1 6
2.5.2 Note 2 7
2.5.3 Note 3 7
2.5.4 Note 4 7
2.5.5 Note 5 8
2.5.6 Note 6 8
Ⅲ. Results and discussion 9
3.1 Characterization of perovskite films and precursors 9
3.2 Stabilization of 3-MBA in perovskite precursor 11
3.3 Film properties of 3-MBA-treated perovskite films 15
3.4 Photovoltaic performance 17
3.5 Stability test of perovskite films and devices 18
Ⅳ. Conclusion 20
Reference 61
요약문 67MasterdCollectio
Unveiling the humidity effect and achieving an unprecedented 12% PCE in MAPbBr3 solar cells
No full textFabricating high-efficiency MAPbBr3 solar cells is challenging due to substantial recombination losses within the perovskite layer and at interfaces with charge transport layers. Here, we investigate the critical role of ambient humidity in improving device performance and stability. We varied humidity levels from dry N2 to 80 % relative humidity (RH) and identified that maintaining the environment at 25 % ± 0.82 % RH optimally enhances the morphological, structural, optical properties of MAPbBr3 films. Our novel analyses demonstrate that this specific humidity level significantly reduces bulk defect densities and interface recombination sites without any additive, leads to the formation of larger crystal grains, and improves optical qualities as well. Consequently, devices fabricated under these conditions achieved the highest device efficiency of 12.14 % for the MAPbBr3 solar cells. Additionally, they exhibited remarkable long-term stability, retaining nearly 90 % of the initial efficiency after 1000 h damp-heat and 100 cycles of thermo-cycling tests with encapsulated devices. © 2024 Elsevier B.V.FALSEsciescopu
악천후 상황 내 강건한 객체 검출을 위한 YOLO 모델 기반의 접근
No full textAdverse Weather, YOLO, Temporal-Ensemble, Image-to-Image Translation ModelThe goal of object detection in adverse weather conditions, such as darkness, fog, rain, and snow, in this paper is crucial for the safety and advancement of autonomous vehicles. Existing YOLO-based models have limitations in overcoming adverse weather conditions, either relying on specific datasets or utilizing image enhancement modules tailored for darkness and fog. Moreover, obtaining real-world adverse weather data is costly compared to acquiring regular weather data, and obtaining a diverse range of such data quantitatively is challenging and time-consuming. This study proposes a method to address the data scarcity issue through image similarity-based quantitative adverse weather data generation techniques and datasets. Additionally, it introduces a methodology using Temporal Ensemble to adapt to adverse weather conditions in real-time. Furthermore, it suggests leveraging light-weighted Image-to-Image Translation Models to enhance object recognition performance in nighttime conditions. Our approach not only makes the training datasets more realistic and diverse but also enables smooth object detection in noisy situations like darkness, fog, rain, and snow.|본 논문의 악천후 상황 내 객체 인식은 어둠 및 흐린 날씨와 비와 눈 등의 악천후 노이즈를 극복하고 원활히 객체를 검출해야 하는 것을 목표로 하며, 이는 자율주행 자동차의 안전 및 자율주행 단계의 발전에 있어 핵심적인 사항이다. 현존하는 YOLO 기반의 모델들은 데이터에 의존하거나 이미지 강화 모듈을 통해 어둠 및 안개 상황 만의 악천후 상황을 극복하는 등의 한계가 있다. 게다가, 실제 세계의 악천후 데이터를 얻는 것은 일반 기상 상황 데이터를 습득하는 데 비해 비용이 많이 들며, 정량적으로 다양한 악천후 데이터를 모두 얻는 것은 시간적으로도 어려운 작업이다. 이 연구에서는 이러한 데이터 부족 문제를 해결하기 위한 이미지 유사도 기반 정량적 악천후 데이터 생성 방법 및 데이터셋, 그리고 Temporal Ensemble을 사용하여 실시간으로 악천후에 대응할 수 있는 방법론을 제시한다. 또한, 더 나아가 경량화한 Image-to-Image Translation Model을 활용하여 밤 상황에서 객체 인식의 성능을 향상하는 방법을 제안하고자 한다. 우리의 방법은 학습에 사용되는 데이터셋을 더 현실적이고 다채롭게 할 수 있을 뿐 아니라, 어둠, 흐림, 비, 눈와 같은 노이즈 상황에서도 원활한 객체 인식을 가능하게 할 수 있다.Ⅰ. Introduction 1
II. Related Works 4
III. Method 7
3.1 Synthetic Adverse Weather Image Preparation 7
3.2 QRAW dataset Generation 8
3.3 Overall Framework of Temporal Ensemble Based YOLO 9
3.4 Overall Framework of Image-to-Image Translation Model Based YOLO 10
IV. Experiments 13
4.1 Result of Adverse Weather Data Generation 13
4.2 Implementation details 14
4.3 Evaluation Metrics 14
4.4 Experimental Results 15
V. Conclusions, Limitations and Future Works 20
References 21
국문초록 25MasterdCollectio
L-DOPA regulates neuroinflammation and Aβ pathology through NEP and ADAM17 in a mouse model of AD
Get PDFDopamine plays important roles in cognitive function and inflammation and therefore is involved in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD). Drugs that increase or maintain dopamine levels in the brain could be a therapeutic strategy for AD. However, the effects of dopamine and its precursor levodopa (L-DOPA) on Aβ/tau pathology in vivo and the underlying molecular mechanisms have not been studied in detail. Here, we investigated whether L-DOPA treatment alters neuroinflammation, Aβ pathology, and tau phosphorylation in 5xFAD mice, a model of AD. We found that L-DOPA administration significantly reduced microgliosis and astrogliosis in 5xFAD mice. In addition, L-DOPA treatment significantly decreased Aβ plaque number by upregulating NEP and ADAM17 levels in 5xFAD mice. However, L-DOPA-treated 5xFAD mice did not exhibit changes in tau hyperphosphorylation or tau kinase levels. These data suggest that L-DOPA alleviates neuroinflammatory responses and Aβ pathology but not tau pathology in this mouse model of AD. © The Author(s) 2024.TRUEsciescopu
False Alarm Prevention Through Domain Knowledge-Driven Machine Learning: Leakage Detection in Water Distribution Networks
No full textEffective management of water distribution networks (WDNs) is critical for conserving water and reducing financial losses. This study addresses the problem of false alarms in WDNs' acoustic loggers, often triggered by electrical transformer noise. We propose a false alarm prevention framework that features a transformer noise-based frequency selection (TNFS) method, utilizing domain knowledge of the system. TNFS provides a uniform feature set without the iterative sampling or sample dependence typical of other methods. Its rapid processing and low computational needs make it exceptionally suitable for WDNs' acoustic loggers with constrained computing resources. In addition, we introduce the generative adversarial network-enhanced synthetic minority over-sampling technique (SMOTE), designed to tackle the mode collapse issue in generative adversarial networks (GANs). Our system, validated with real-world data spanning 17 months, dramatically reduces false alarms from electrical noise by 99.6%, highlighting the importance of domain-specific knowledge in the application of machine learning to industrial sensor networks.FALSEsciescopu