• Earthquakes and Structures
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• v.17 no.5
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• pp.477-487
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• 2019

Understanding the behavior of skew bridges under the action of earthquakes is quite challenging due to the combined transverse and longitudinal responses even under unidirectional hit. The main goal of this research is to assess the response of skew bridges when subjected to longitudinal and transversal earthquake loading. The effect of skew on the response considering two- and three- span bridges with skew angles varying from 0 to 60 degrees is illustrated. Various pier fixities (and hence stiffness) and cross-section shapes, as well as different abutment's bearing articulations, are also studied. Finite-element models are established for modal and seismic analyses. Around 900 models are analyzed under the action of the code design response spectrum. $Vis-{\grave{a}}-vis$ modal properties, the higher the skew angle, the less the fundamental period. In addition, it is found that bridges with skew angles less than 30 degrees can be treated as straight bridges for the purpose of calculating modal mass participation factors. Other monitored results are bearings' reactions at abutments, shear and torsion demand in piers, as well as deck longitudinal displacement. Unlike straight bridges, it has been typically noted that skew bridges experience non-negligible torsion and bi-directional pier base shears. In a complementary effort to assess the accuracy of the conducted response spectrum analysis, a series of time-history analyses are applied under seven actual earthquake records scaled to match the code design response spectrum and critical comparisons are performed.

• Research in Community and Public Health Nursing
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• v.30 no.1
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• pp.1-10
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• 2019

Purpose: This study tries to analyze the concept of Yangsaeng in the Korean aged, with focus on nursing. Methods: Rodgers' evolutionary approach was used to identify the common definitions, attributes, antecedents, and consequences of the Yangsaeng concept for the aged. Literature search was conducted at the NAL, NDSL, RISS, ProQuest, PubMed, AMED, and MEDLINE databases from 2004 to 2016, using the keywords "Yangsaeng," "health promotion," "health management," "traditional oriental methods," and "traditional oriental nursing."Finally, 20 relevant articles were selected and thoroughly reviewed. Results: The analysis shows that the model of Yangsaeng for the Korean aged is that of personal adaptive-capacity, totality, challenging, and coping resource and includes physical, social and psychological health and wellness. Conclusion: This work provides some implications on the development of nursing intervention related with Yangsaeng for the Korean aged, and suggests the implementation of such intervention in the practice of Yangsaeng for the Korean aged. Therefore, a better understanding of the Korean aged and Yangsaeng within the context of nursing can be achieved.

• Journal of Korea Multimedia Society
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• v.22 no.2
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• pp.136-145
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• 2019

The crowded environment of a domestic pig farm is highly vulnerable to the spread of infectious diseases such as foot-and-mouth disease, and studies have been conducted to automatically analyze behavior of pigs in a crowded pig farm through a video surveillance system using a camera. Although it is required to correctly separate occluding pigs for tracking each individual pigs, extracting the boundaries of the occluding pigs fast and accurately is a challenging issue due to the complicated occlusion patterns such as X shape and T shape. In this study, we propose a fast and accurate method to separate occluding pigs not only by exploiting the characteristics (i.e., one of the fast deep learning-based object detectors) of You Only Look Once, YOLO, but also by overcoming the limitation (i.e., the bounding box-based object detector) of YOLO with the test-time data augmentation of rotation. Experimental results with two-pigs occlusion patterns show that the proposed method can provide better accuracy and processing speed than one of the state-of-the-art widely used deep learning-based segmentation techniques such as Mask R-CNN (i.e., the performance improvement over Mask R-CNN was about 11 times, in terms of the accuracy/processing speed performance metrics).

• Restorative Dentistry and Endodontics
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• v.43 no.4
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• pp.38.1-38.9
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• 2018

The restoration of endodontically treated teeth (ETT) with more than one cusp missing and thin remaining walls is challenging for the general practitioner. The use of posts combined with full coverage restorations is a well-established approach, yet not following the minimal invasive principles of adhesive dentistry. Endocrowns are indirect monoblock restorations that use the pulp chamber of the ETT for retention. In this study the fabrication of 4 endocrowns and their clinical performance will be discussed. Two clinical cases include computer-aided design/computer-aided manufacturing manufactured molar endocrowns (one feldspathic ceramic and one hybrid composite-ceramic restoration) and the other two are dental laboratory manufactured resin composite premolar endocrown restorations. The modified United States Public Health Service criteria were used to assess the clinical behavior of the restorations at different follow up periods. Endocrown restorations present a satisfactory clinical alternative, either by the use of resin composite or glass ceramic and hybrid materials. Specific guidelines with minimal alterations should be followed for an endocrown restoration to be successful. Due to limited evidence regarding the long term evaluation of this restorative technique, a careful selection of cases should be applied.

• Archives of Craniofacial Surgery
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• v.20 no.2
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• pp.139-143
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• 2019

Here we report a case of a focal atypical proliferative nodule (PN) arising from a congenital melanocytic nevus (CMN). Diagnosis was challenging because it had both benign and malignant clinical features. Unusual histopathology, immunohistochemistry, and intraoperative findings of this atypical PN are discussed. A 5-year-old girl was admitted for a congenital $5{\times}5cm$ sized scalp mass. This hemangioma-like soft mass showed biphasic characteristics such as a slow, gradual, and benign increase in size but worrisome dural invasion with cranial bone defect. We removed the scalp mass with clear resection margins. Interoperatively, we found that the cranial bone defect had already filled. Histopathologic examination showed CMN with focal atypical PN. The nodule showed sharp demarcation and cellular pleomorphism. However, in immunohistochemical study, Ki-67 proliferation index and expression levels of protein S-100 and Melan-A were very low. These were unusual findings of atypical PNs. Despite her worrisome preoperative radiologic features, she showed an indolent clinical course compatible with previously reported biologic behavior. The patient underwent follow-up inspection with magnetic resonance imaging every 6 months for up to 3 years. The nodule appeared to be stationary at the last visit.

• BMB Reports
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• v.55 no.5
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• pp.238-243
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• 2022

Autism or autism spectrum disorder (ASD) is a behavioral syndrome characterized by persistent deficits in social interaction, and repetitive patterns of behavior, interests, or activities. The gene encoding Methyl-CpG binding protein 2 (MeCP2) is one of a few exceptional genes of established causal effect in ASD. Although genetically engineered mice studies may shed light on how MeCP2 loss affects synaptic activity patterns across the whole brain, such studies are not considered practical in ASD patients due to the overall level of impairment, and are technically challenging in mice. For the first time, we show that hippocampal MeCP2 knockdown produces behavioral abnormalities associated with autism-like traits in rats, providing a new strategy to investigate the efficacy of therapeutics in ASD. Ketamine, an N-Methyl-D-aspartate (NMDA) blocker, has been proposed as a possible treatment for autism. Using the MeCP2 knockdown rats in conjunction with a rat model of valproic acid (VPA)-induced ASD, we examined gene expression and ASD behaviors upon ketamine treatment. We report that the core symptoms of autism in MeCP2 knockdown rats with social impairment recovered dramatically following a single treatment with ketamine.

• Structural Engineering and Mechanics
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• v.84 no.1
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• pp.101-111
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• 2022

It is widely known that axially loaded fiber-reinforced polymer (FRP) confined concrete presents significant and enhanced mechanical properties with reference to the unconfined concrete. Therefore, to predict the mechanical behavior of FRP-confined concrete two quantities-peak strength and ultimate strain are required. Despite the significant advances, the determination of the ultimate strain of FRP-confined concrete is one of the most challenging problems to be resolved. This is often attributed to our persistence in desiring the conventional methods as the sole technique to examine this phenomenon and the complex nature of the ultimate strain of FRP-confined concrete. To bridge the research gap, this study adopted two machine learning (ML) techniques-artificial neural network (ANN) and Gaussian process regression (GPR)-to analyze observations obtained from 627 datasets of FRP-confined concrete circular and non-circular sections under axial loading test. Besides, the techniques are also used to predict the ultimate strain of FRP-confined concrete. Seven parameters namely width/diameter of the specimens, corner radius ratio, the strength of concrete, FRP elastic modulus, FRP thickness, FRP tensile rupture strain, and the axial strain of unconfined concrete-are the input parameters used to predict the ultimate strain of FRP-confined concrete. The results of the current study highlight the merit of using AI techniques in structural engineering applications given their extraordinary ability to comprehend multidimensional phenomena of FRP-confined concrete structures with ease, low computational cost, and high performance over the existing empirical models.

• Membrane and Water Treatment
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• v.14 no.3
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• pp.141-146
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• 2023

Algal organic matters (AOMs) are challenging to remove using traditional water treatment methods. Additionally, they are recognized as disinfection by product (DBP) precursors during the chlorination process. These compounds have the potential to seriously harm aquatic creatures. Despite the fact that AOMs and DBPs formed from algae can harm aquatic species by impairing their cognitive function and causing behavioral problems, only a few studies on the effects of AOMs and associated DBPs have been conducted. To assess the impact of extracellular organic materials (EOMs) produced by three different hazardous algal species and the chlorinated EOMs on zebrafish, this study used fish acute embryo toxicity (FET) and cognitive function tests. With rising EOM concentrations, the embryo's survival rate and mental capacity both declined. Of the three algal species, the embryo exposed to Microcystis aeruginosa EOM exhibited the lowest survival rate. On the other hand, the embryo exposed to EOMs following chlorination demonstrated a drop in CT values in both the survival rate and cognitive ability. These findings imply that EOMs and EOMs treated with chlorine may have detrimental effects on aquatic life. Therefore, an effective EOM management is needed in aquatic environment.

• Journal of Distribution Science
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• v.21 no.7
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• pp.1-9
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• 2023

Purpose: This study aims to understand if heterogeneous news is evenly consumed and distributed on portals as it examines people's news use and engagement behaviors and news credibility. Focusing on the four behaviors of news use, i.e., viewing news by keyword search, viewing news from subscribed sources, viewing news from the list of most-viewed news, and reading comments, and the three behaviors of news engagement, i.e., sharing news, 'liking' or 'recommending' news, and posting comments, this study investigates the relation between each of the behaviors and portal news credibility. Research design, data and methodology: From 2022 News Audience Survey in Korea, this study conducts a regression analysis to investigate the relations between each behavior and news credibility. Results: The results show a positive relation for the former two news use behaviors and the latter two news engagement behaviors, and a negative relation for the latter two news use behaviors. Conclusions: The positive relations between active news use and engagement behaviors and portal news credibility indicate that news consumers are more likely to use and engage in attitude-consistent news rather than attitude-challenging news, implying that heterogeneous news is less likely to be consumed and distributed evenly on portals across all news users.

• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1630-1643
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• 2023

The correct situation awareness (SA) of operators is important for managing nuclear power plants (NPPs), particularly in accident-related situations. Among the three levels of SA suggested by Ensley, Level 3 SA (i.e., projection of the future status of the situation) is challenging because of the complexity of NPPs as well as the uncertainty of accidents. Hence, several prediction methods using artificial intelligence techniques have been proposed to assist operators in accident prediction. However, these methods only predict short-term plant status (e.g., the status after a few minutes) and do not provide information regarding the uncertainty associated with the prediction. This paper proposes an algorithm that can predict the multivariate and long-term behavior of plant parameters for 2 h with 120 steps and provide the uncertainty of the prediction. The algorithm applies bidirectional long short-term memory and an attention mechanism, which enable the algorithm to predict the precise long-term trends of the parameters with high prediction accuracy. A conditional variational autoencoder was used to provide uncertainty information about the network prediction. The algorithm was trained, optimized, and validated using a compact nuclear simulator for a Westinghouse 900 MWe NPP.