• Coupled systems mechanics
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• 제7권5호
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• pp.555-581
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• 2018

The moment-resistant steel frames are frequently used as a load-bearing structure of buildings. Global response of a moment-resistant frame structure strongly depends on connections behavior, which can significantly influence the response and load-bearing capacity of a steel frame structure. The analysis of a steel frame with included joints behavior is the main focus of this work. In particular, we analyze the behavior of two connection types through experimental tests, and we propose numerical beam model capable of representing connection behavior. The six experimental tests, under monotonic and cyclic loading, are performed for two different types of structural connections: end plate connection with an extended plate and end plate connection. The proposed damage-plasticity model of Reissner beam is able to capture both hardening and softening response under monotonic and cyclic loading. This model has 18 constitutive parameters, whose identification requires an elaborate procedure, which we illustrate in this work. We also present appropriate loading program and arrangement of measuring equipment, which is crucial for successful identification of constitutive parameters. Finally, throughout several practical examples, we illustrate that the steel structure connections are very important for correct prediction of the global steel frame structure response.

• 한국해양공학회지
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• 제32권2호
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• pp.116-122
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• 2018

Dean's equilibrium beach profile formula was used to investigate the correlation between the static shoreline position and the incident wave energy. The effect of the longshore sediment transport was neglected, and the results showed the reasonable agreement compared with the field observations of Yates et al.(2009), which were conducted for almost 5 years on southern California beaches, USA. The shoreline response varies with the scale factor of Dean's equilibrium beach profile. This implies that the shoreline response could be simply estimated using the sampled grain size without laborious long-term field work. Therefore, the present study results are expected to be practically used for the layout design of submerged or exposed detached breakwaters although the further work is required for performance verification. In addition, after laborous mathematical reviews, the linear relation between incident energy and shoreline response, which was obtained from Yates's field study, yielded a clear mathematical equation showing how the beach slope is related to the grain size.

• Safety and Health at Work
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• 제9권3호
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• pp.352-355
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• 2018

Hazardous work zones (i.e., hot, warm, and cold) are typically established by emergency response teams during hazardous materials (HAZMAT) calls but less consistently for fire responses to segment personnel and response activities in the immediate geographic area around the fire. Despite national guidelines, studies have documented the inconsistent use of respiratory protective equipment by firefighters at the fire scene. In this case-series report, we describe warm zone gas levels using multigas detectors across five independent fire incident responses all occurring in a large South Florida fire department. Multigas detector data collected at each fire response indicate the presence of sustained levels of volatile organic compounds in the "warm zone" of each fire event. These cases suggest that firefighters should not only implement strategies for multigas detector use within the warm zone but also include respiratory protection to provide adequate safety from toxic exposures in the warm zone.

• 지역사회간호학회지
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• 제32권4호
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• pp.578-592
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• 2021

Purpose: The purpose of this study was to examine the experiences of public officials working for the Coronavirus Disease-19 (COVID-19) response in community health centers in South Korea. Methods: A qualitative thematic analysis was conducted using data collected from three focus groups and two individual interviews. Results: The participants performed quarantine tasks in a poor working environment with several problems, such as significant workload, lack of manpower, and inappropriate compensation system. Participants experienced obstacles in performing quarantine works, which had the lack of the detailed quarantine guidelines, work support and cooperation system. Participants suffered from civil complaints. Participants endured sacrifices in their personal lives while partaking in COVID-19 response work without holidays, and subsequently experienced health problems. And also participants said that it was necessary to secure expertise and effective communication for infectious disease management. Conclusion: The study results suggest that policies are required that are aimed to improve the working environment and the recruitment of experts in infectious diseases. In addition, the job stress related to the COVID-19 response by public officials in community health centers must be evaluated, and the relation of their job stress to physical and mental problems, as well as psychosocial stress, must be examined.

• 무역학회지
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• 제46권1호
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• pp.135-154
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• 2021

This study aims to investigate the difference in the perception of shippers on the quality of air freight service between air express and air freight forwarders. This study suggests hypothesis verification and implications on importance-performance between two groups of air express and air freight forwarders. In this study, we find that important variables through paired t-test and importance-performance analysis. As a result of paired t-test, there was a difference in the use variables of the document work variables through computerization in the importance area. In the satisfaction area, there was a difference between the groups in the response to customer request and the response to accidents. The variables that need to improve the focus derived from the importance-performance analysis are document work through computer and response to accidents. It is necessary to observe and manage the response of shippers continuously by holding various transportation schedules in the schedule area, possibility of adjustment of transportation schedule, regular freight and schedule provision.

• Bulletin of the Korean Chemical Society
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• 제24권8호
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• pp.1102-1106
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• 2003

In our previous work we developed the Finite Field method in order to calculate the fifth-order Raman response. The method was applied to calculate various polarization components of the two-dimensional response of liquid $CS_2$. So far, all calculations relied on the dipole-induced dipole. Accurate time-dependent density functional theory calculations have shown that this model has big discrepancies, when molecules are close together as in the liquid. We now report results of investigations on the importance of multipole and electron overlap effects on the polarizability and the fifth-order Raman response. It is shown that these collision effects, especially the induced multipoles, are crucial in the description of the fifth-order response. The impact is found to be especially pronounced for the χ_{mmzzzz}^{(5)}$response that is solely due to interaction induced effects. The calculated response will be compared with various experimental results.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.48.6-48
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• 2002

in this paper, each methodology, e.g. normal single PID controller, direct synthesis method and inverse response compensator, will be compared to determine the best inverse response plant control method, by based on the appearance of the control performance and robustness from the simulation results. The flexibility of being able to maintain the system stability during the presence of plant model mismatch is one of the criteria to measure the robustness of overall control system. Once, plant has changed the condition, the model will need to be updated. Hence, the designed controller will not work properly. The caused of plant model mismatch is stayed by definition unknown but the most possib...

• 한국응급구조학회지
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• 제19권3호
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• pp.33-49
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• 2015

Purpose: This study aimed to investigate the work and job satisfaction of military emergency medical technicians (EMTs). Methods: We selected 122 military EMTs who participated in the refresher education in 2012. This study was conducted from November 12 to December 21, 2012. Results: The most frequent duties of military EMTs were scene assessment, cardiopulmonary resuscitation, surgical treatment, prehospital first-aid, transfer to the hospital, education, and call response. The air force and navy EMTs had better performance than the army EMTs. As for job satisfaction, the work itself ranked highest, whereas payment ranked lowest. Conclusion: The scope of the work of the military EMTs varied in the 14 fields of work but should be considered for further evaluation. In order to increase the job satisfaction of EMTs, their work conditions should be improved such as through salary increase and extra pay for those with professional certificates.

• Communications for Statistical Applications and Methods
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• 제31권2호
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• pp.179-189
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• 2024

In multivariate regression with a high-dimensional response Y ∈ ℝ^r and a relatively low-dimensional predictor X ∈ ℝ^p (where r ≥ 2), the statistical analysis of such data presents significant challenges due to the exponential increase in the number of parameters as the dimension of the response grows. Most existing dimension reduction techniques primarily focus on reducing the dimension of the predictors (X), not the dimension of the response variable (Y). Yoo and Cook (2008) introduced a response dimension reduction method that preserves information about the conditional mean E(Y | X). Building upon this foundational work, Yoo (2018) proposed two semi-parametric methods, principal response reduction (PRR) and principal fitted response reduction (PFRR), then expanded these methods to unstructured principal fitted response reduction (UPFRR) (Yoo, 2019). This paper reviews these four response dimension reduction methodologies mentioned above. In addition, it introduces the implementation of the mbrdr package in R. The mbrdr is a unique tool in the R community, as it is specifically designed for response dimension reduction, setting it apart from existing dimension reduction packages that focus solely on predictors.

• Safety and Health at Work
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• 제12권1호
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• pp.139-139
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• 2021