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The Oh-Park methodology was proposed to overcome the limitations of Steinberg's theory for evaluating the structural safety of space-borne electronics and has been experimentally verified at the printed circuit board (PCB) specimen level for various types of electronic packages, such as ball grid arrays (BGAs), column grid arrays (CGAs), and small-outline packages (SOPs). However, it is necessary to validate the design methodology because the PCB mounted on the housing is affected by the elastic mode of the mechanical housing. In addition, although the validity of the existing theory based on critical strain has been verified for horizontally mounted structures, there are cases where PCBs are mounted vertically. Therefore, it is essential to consider the dynamic influence of the boundary conditions of mounted electronics. In this study, electronics specimens with corresponding boundary conditions were fabricated, and a fatigue-life test was performed. In addition, a structural analysis using Steinberg's theory and the Oh-Park methodology was performed, and the results were compared with those of the fatigue-life test. The results showed that the analysis using the Oh-Park methodology accurately represented the test results, and the validity of the Oh-Park methodology for vertical electronics was verified experimentally. [ABSTRACT FROM AUTHOR]

Refresh rate is an important specification for gaming OLED monitors. With the development of the gaming industry and the graphics processing unit (GPU), the demand for gaming monitors that supporting high refresh rates is increasing. In this paper, simulation methods for perceived motion blur are proposed to predict the degree of blur according to the refresh rate. Experimental results indicate that the proposed simulation methods are quite effective in predicting the degree of motion blur. In addition, this paper presents the predicted results of blur as the refresh rate increases up to 480Hz. [ABSTRACT FROM AUTHOR]

Background: Accurate detection of axillary lymph node (ALN) metastases in breast cancer is crucial for clinical staging and treatment planning. This study aims to develop a deep learning model using clinical implication-applied preprocessed computed tomography (CT) images to enhance the prediction of ALN metastasis in breast cancer patients. Methods: A total of 1128 axial CT images of ALN (538 malignant and 590 benign lymph nodes) were collected from 523 breast cancer patients who underwent preoperative CT scans between January 2012 and July 2022 at Hallym University Medical Center. To develop an optimal deep learning model for distinguishing metastatic ALN from benign ALN, a CT image preprocessing protocol with clinical implications and two different cropping methods (fixed size crop [FSC] method and adjustable square crop [ASC] method) were employed. The images were analyzed using three different convolutional neural network (CNN) architectures (ResNet, DenseNet, and EfficientNet). Ensemble methods involving and combining the selection of the two best-performing CNN architectures from each cropping method were applied to generate the final result. Results: For the two different cropping methods, DenseNet consistently outperformed ResNet and EfficientNet. The area under the receiver operating characteristic curve (AUROC) for DenseNet, using the FSC and ASC methods, was 0.934 and 0.939, respectively. The ensemble model, which combines the performance of the DenseNet121 architecture for both cropping methods, delivered outstanding results with an AUROC of 0.968, an accuracy of 0.938, a sensitivity of 0.980, and a specificity of 0.903. Furthermore, distinct trends observed in gradient-weighted class activation mapping images with the two cropping methods suggest that our deep learning model not only evaluates the lymph node itself, but also distinguishes subtler changes in lymph node margin and adjacent soft tissue, which often elude human interpretation. Conclusions: This research demonstrates the promising performance of a deep learning model in accurately detecting malignant ALNs in breast cancer patients using CT images. The integration of clinical considerations into image processing and the utilization of ensemble methods further improved diagnostic precision. [ABSTRACT FROM AUTHOR]

We demonstrate a series of multifunctional micro-photodetectors (μPDs) designed for high-speed ultraviolet-A-(UVA)-light detection and blue-light illumination based on InGaN/GaN triple-quantum-well devices grown on patterned sapphire substrates. At forward voltage bias, the device operated as a light-emitting diode with a peak emission wavelength of ∼450 nm. When switching to reverse voltage bias, the device exhibited a dual-band responsivity of 0.17 A/W at 370 nm and 0.14 A/W at 400 nm, indicating effective UVA light detection. Furthermore, size-dependent emission and detection behaviors were investigated with the device's active area having radii ranging from 15 to 50 μm. For μPDs, the −3-dB bandwidth increased with the reduced device radius and reached a maximum of 689 MHz for the 15-μm device under −10-V bias. High responsivity and fast modulation speed contributed to 2-Gb/s UVA optical wireless communication based on direct-current-biased optical orthogonal frequency-division multiplexing. The research offers a promising approach to simultaneous high-speed communication and illumination in the UVA-blue-light optical spectral regime, and the dual-band responsivity feature is potentially useful for increasing channel capacity. [ABSTRACT FROM AUTHOR]

In‐Plane Switching (IPS) liquid crystal display (LCD) is one of leading technologies in display industrials because of its superior picture quality. This paper provides picture quality of high contrast IPS LCD in terms of color contrast, dynamic range, color expression and PQ‐EOTF accuracy in HDR compared to conventional IPS LCD. Furthermore, to evaluate its performance as a gaming display, reaction time between two IPS LCDs have different contrast ratio was tested. Experimental results indicate that observer's reaction time for high contrast IPS LCD was faster than conventional IPS LCD because of superior color contrast and color gamut at low luminance level. [ABSTRACT FROM AUTHOR]