• Earthquakes and Structures
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• v.20 no.4
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• pp.377-388
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• 2021

Thin perforated Steel Plate Shear Walls (SPSWs) are among the most common types of seismic energy dissipation systems to protect the main boundary components of SPSWs from fatal fractures in the high-risk zones. In this paper, the cyclic behavior of the different circular hole patterns under cyclic loading is reported. Based on the experimental results, it can be concluded that a change in the perforation pattern of the circular holes leads to a change in the locations of the fracture tendency over the web plate, especially at the plate-frame interactions. Accordingly, the cyclic responses of the tested specimens were simulated by finite element method using the ABAQUS package. Likewise, perforated shear panels with a new perforation pattern obtained by implementing Topology Optimization (TO) were proposed. It was found that the ultimate shear strength of the specimen with the proposed TO perforation pattern was higher than that of the other specimens. In addition, theoretical equations using the Plate-Frame Interaction (PFI) method were used to predict the shear strength and initial stiffness of the considered specimens. The theoretical results showed that the proposed reduced coefficients relationships cannot accurately predict the shear strength and initial stiffness of the considered perforated shear panels. Therefore, the reduced coefficients should be adopted in the theoretical equations based on the obtained experimental and numerical results. Finally, with the results of this study, the shear strength and initial stiffness of these types of perforated shear panels can be predicted by PFI method.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.8
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• pp.699-708
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• 2021

In this paper, the aerodynamic and aeroacoustic characteristics that vary depending on the rotation axial distance between the upper and lower rotor, which is one of the design parameters of the coaxial rotor, is analyzed in the hovering condition using the computational fluid dynamics. Aerodynamic analysis using the Reynolds Averaged Navier Stokes equation and the aeroacoustic analysis using the Ffowcs Williams ans Hawkings equation is performed and the results were compared. The upper and lower rotor of the coaxial rotor have different phase angle which changes periodically by rotation and have unsteady characteristics. As the distance between the upper and lower rotors increased, the aerodynamic efficiency of the thrust and the torque was increased as the flow interaction decreased. In the aeroacoustic viewpoint, the noise characteristics radiated in the direction of the rotational plane showed little effect by axis spacing. In the vertical downward direction of the axis increased, the SPL maintains its size as the frequency increases, which affects the increase in the OASPL. As the axial distance of the coaxial rotor increased, the noise characteristics of a coaxial rotor were similar with the single rotor and the SPL decreased significantly.

• Genomics & Informatics
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• v.19 no.1
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• pp.6.1-6.10
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• 2021

Vascular endothelial growth factor (VEGF) is expressed at elevated levels by most cancer cells, which can stimulate vascular endothelial cell growth, survival, proliferation as well as trigger angiogenesis modulated by VEGF and VEGFR (a tyrosine kinase receptor) signaling. The angiogenic effects of the VEGF family are thought to be primarily mediated through the interaction of VEGF with VEGFR-2. Targeting this signaling molecule and its receptor is a novel approach for blocking angiogenesis. In recent years virtual high throughput screening has emerged as a widely accepted powerful technique in the identification of novel and diverse leads. The high resolution X-ray structure of VEGF has paved the way to introduce new small molecular inhibitors by structure-based virtual screening. In this study using different alkaloid molecules as potential novel inhibitors of VEGF, we proposed three alkaloid candidates for inhibiting VEGF and VEGFR mediated angiogenesis. As these three alkaloid compounds exhibited high scoring functions, which also highlights their high binding ability, it is evident that these alkaloids can be taken to further drug development pipelines for use as novel lead compounds to design new and effective drugs against cancer.

• Journal of the Korea Convergence Society
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• v.9 no.12
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• pp.239-250
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• 2018

This study focus on analyzing the factors which influence the customer satisfaction of food delivery application and its degree of the influence on the quality satisfaction both with Korean and Chinese customers. For this purpose, the model of hypothetical structure was established through the mobile internet service quality measurement was called as MOBISQUAL. As a result, the Korean customers was confirmed that the fulfillment and playfulness as the subdimension of outcome quality both have a positive effect on customer satisfaction. And the Chinese customer was confirmed that the playfulness of outcome quality, personalization of contextual interaction, design, ease of use and security of servicescape quality affected customer satisfaction positively.

• Health Policy and Management
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• v.29 no.2
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• pp.228-236
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• 2019

Background: This study investigates the impact of weekend admission with a patient safety indicator (PSI) on 30-day mortality among long-term insurance beneficiaries. Methods: Data were obtained from the National Health Insurance Service-Senior claim database from 2002 to 2013. To obtain unbiased estimates of odds ratio, we used a nested case-control study design. The cases were individuals who had a 30-day mortality event after their last medical utilization, while controls were selected by incidence density sampling based on age and sex. We examined the interaction between the main independent variables of weekend admission and PSI by categorizing cases into four groups: weekend admission/PSI, weekend admission/non-PSI, weekday admission/PSI, and weekday admission/non-PSI. Results: Of the 83,400 individuals in the database, there were 20,854 cases (25.0%) and 62,546 controls (75.0%). After adjusting for socioeconomic, health status, seasonality, and hospital-level factors, the odds ratios (ORs) of 30-day mortality for weekend admission/PSI (OR, 1.484; 95% confidence interval [CI], 1.371-1.606) and weekday admission/PSI (OR, 1.357; 95% CI, 1.298-1.419) were greater than for patients with weekday admission/non-PSI. Conclusion: This study indicated that there is an increased risk of mortality after weekend admission among patients with PSI as compared with patients admitted during the weekday without a PSI. Therefore, our findings suggest that recognizing these different patterns is important to identify at-risk diagnosis to minimize the excess mortality associated with weekend admission in those with PSI.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.26 no.1
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• pp.62-73
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• 2019

Purpose: The purpose of this study was to estimate the effects of a video low intensity exercise program provided during hemodialysis on fatigue, activity of daily living, positive psychological capital and blood pressure of patients being treated. Methods: A non-equivalent control group pre-post test design was used. Participants were 85 hemodialysis patients assigned to either the experimental group (n=41) or the control group (n=44). The experimental group exercised for about 25 minutes 3 times a week for 8 weeks. Data analyses involved descriptive statistics, $x^2$ test, t-test, multiple regression and repeated measure ANOVA using SPSS/WIN 23.0. Results: The exercise intervention significantly reduced post hemodialysis fatigue and significantly increased positive psychological capital. There was a significant interaction effect on time by group in blood pressure. Systolic blood pressure changes in the experimental group were stable but, changes in the control group tended to increase gradually. Conclusion: To reduce fatigue and increase positive psychological capital for hemodialysis patients, providing exercise during hemodialysis is recommended. Furthermore individualized exercise in terms of intensity, time, duration, etc should be developed and tested. Also, to reduce drastic blood pressure changes during hemodialysis, exercise should be provided.

• Structural Engineering and Mechanics
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• v.69 no.3
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• pp.257-268
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• 2019

Infills are as important members in structural design as beams, columns and braces. They have significant effect on structural behavior. Because of lots of variables in infills like material non-linear behavior, the interaction between frames and infill, etc., the infills performance during an earthquake is complicated, so have led designers do not consider the effect of infills in designing the structure. However, the experimental studies revealed that the infills have the remarkable effect on structure behavior. As if these effects ignored, it might occur soft-story phenomena, torsion or short-column effects on the structures. One simple and appropriate method for considering the infills effects in analyzing, is replacing the infills with diagonal compression strut with the same performance of real infill, instead of designing the whole infill. Because of too many uncertainties, codes and researchers gave many expressions that were not as the same as the others. The major intent of this paper is calculation the width of this diagonal strut, which has the most characteristics of infill. This paper by comprehensive on different parameters like the modulus of young or moment of inertia of columns presents a new formula for achieving the equivalent strut width. In fact, this new formula is extracted from about 60 FEM analyses models. It can be said that this formula is very efficient and accurate in estimating the equivalent strut width, considering the large number of effective parameters relative to similar relationships provided by other researchers. In most cases, the results are so close to the values obtained by the FEM. In this formula, the effect of out of plane buckling is neglected and this formula is used just in steel structures. Also, the thickness of infill panel, and the lateral force applied to frame are constant. In addition, this new formula is just for modeling the lateral stiffness. Obtaining the nearest response in analyzing is important to the designers, so this new formula can help them to reach more accurate response among a lot of experimental equations proposed by researchers.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.1
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• pp.110-117
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• 2019

Objective: An experiment was conducted to evaluate the effects of dietary glutamine (Gln) and arginine (Arg) supplementation on performance, intestinal morphology and ascites mortality in broilers. Methods: A total of 675 day old chicks were randomly allocated to 9 experimental groups in a $3{\times}3$ factorial arrangement based on a completely randomized design with 5 replicates of 15 chicks. Three levels of dietary Gln (0%, 0.5%, and 1%) and Arg (100%, 130%, and 160% of Ross recommendation) supplementation were used in ascites inducing condition ($15^{\circ}C{\pm}1^{\circ}C$) from 7 to 42 days of age. Results: Dietary supplementation of Gln increased body weight gain during grower, finisher and total periods (p<0.05) and increased feed intake during total period. Ascites mortality was decreased by Gln supplementation (p<0.05). Gln supplementation increased the villus height (VH) and crypt depth (CD) in duodenum and jejunum (p<0.05). Arg supplementation decreased CD in duodenum and jejunum, and increased ileum villus width (VW) and also VH/CD ratio in duodenum and jejunum (p<0.05). Both Gln and Arg increased the goblet cell number (GCN) in duodenum whereas Gln supplementation decreased GCN in jejunum and ileum (p<0.05). The $Gln{\times}Arg$ interaction were observed for right ventricle (RV)/total ventricular (TV) ratio, VH, VW, CD, VH/CD. Conclusion: It was concluded that dietary 0.5% Gln alone or along with 130% Arg of Ross requirement, improve the intestinal morphology and performance and hence decrease the ascites mortality in broiler chickens with cold induced ascites.

• Journal of Service Research and Studies
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• v.8 no.4
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• pp.53-75
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• 2018

Bicycle-sharing as a product service system in the sharing economy, its characteristic is that users can go to nearby places by the public bike at any time however they don't need to have their own bicycle. However, the service quality of bicycle-sharing and satisfaction of users continuously decrease with the rapid growth number of bicycle-sharing users in China. Based on the double diamond model and from the perspective of service design, this research studies the service experience of bicycle-sharing of Chinese users, focuses on the potential pain points of Chinese users when using the public bike, and designs the optimum proposal to promote users' satisfaction. According to the research result, the research builds a new concept which can satisfy users' demand for communication, enjoyment and option during the cycling. The experience of new service system of bicycle-sharing makes humanized and subconscious interaction possible.

• The Journal of Information Systems
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• v.28 no.3
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• pp.83-104
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• 2019

Purpose Recently, Internet personal broadcasting has been widely spreaded as a new media type by replacing traditional legacy media such as TV. Considering this phenomenon, this study aims to explore the effect of Aristoteles' persuasion factors on Internet personal broadcasting from a rhetorical view. The reason why users watch the Internet personal broadcasting is that they are persuaded by creator's expertness, empathy, or content usefulness. These factors can be regarded as persuasion factors. Therefore, with Aristoteles' rhetorical persuasion factors composed of ethos, pathos, and logos, this paper tries to investigate how persuasion factors affect user's emotional\ attachment and voluntary donation intention. Design/methodology/approach This paper proposes a model of the relationships among three rhetorical factors, user's emotional attachment, and donation intention. Specifically, ethos is regarded as creator's expertness and trustworthiness, and pathos refers to creator's empathy and social interaction. Last, logos refers to content usefulness and credibility. For testing a hypothetical research model, this study collected 468 surveys and empirically tested hypotheses using a structural equation model. Findings This study investigated how rhetorical factors (ethos, pathos, and logos) and emotional attachment further influence user's donation intention. The findings suggest that rhetorical factors of ethos and pathos enhances emotional attachment, followed by donation intention. Contrary to an expectation, however, logos was not significantly related to emotional attachment. Creators of Internet personal media and MCN providers should focus on the different effects of rhetorical factors and pay attention to the role of emotional attachment to encourage user donation.