• Journal of the Korean Society of Safety
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• v.34 no.3
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• pp.50-56
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• 2019

Precast members have relatively good quality because they are manufactured in an environment suitable for quality control. A typical precast method in which pre-fabricated segments are assembled in the field requires a joint. Although the joint is a small part of the member, it greatly affects the behavior and quality of the structural member. In the previous study of this paper, the flexural strength of a joint, which is generally applied to half-depth precast deck systems, was verified to have higher strength than the design requirement. In addition, the proposed joint has been verified to have higher strength by reinforcing the connecting rebar. However, even if the flexural strength of the joints is sufficient, excessive deflection or lack of fatigue performance is likely to cause cracks in the half-depth precast deck system. In this study, the serviceability of the half-deck precast panel specimens with joints was evaluated and the experimental verification was conducted to evaluate the fatigue performance of the joint without connection rebar. As a result, the serviceability such as deflection and crack width was found to be higher than the design requirement in all the specimens. In the fatigue test, the fatigue effect was insignificant even in the absence of connection rebar.

• The Journal of Health Technology Assessment
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• v.6 no.2
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• pp.88-94
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• 2018

This review aims to provide implications for relevant domestic policies and researches from Patient-Centered Medical Home (PCMH), a reinforcement model for primary care and its evaluations in the United States. As chronic diseases became dominant, changes in the health care delivery system in which primary care is central was required. The United States initiated primary care-reinforcing policies based on the PCMH following the increased demand for evidence-based health care policies. The current activities of the United States such as sharing research tools used to evaluate primary care interventions and circulating evaluation findings provide examples to Korea. Systematic evaluations for primary care interventions are required and appropriate methods using various types of data to reflect the real-world settings should be prepared. It is necessary to conduct policy assessment studies of public interests considering regional context. Support for the researches to make and advance from the existing environment must be examined.

• Architectural research
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• v.22 no.4
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• pp.105-112
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• 2020

The purpose of this study is to establish a method for assessing a building's risk against disaster, tentatively named the Korean integrated disaster evaluation simulator (K-IDES). Based on previous studies, FEMA's risk management series and FEMA IRVS are selected as case studies for developing a frame work of K-IDES, through the comparative analysis of domestic building design guides, codes, and special acts related to disasters, in order to develop a risk assessment methodology for quantitative results. The assessment method consists of a classification system and calculating risk, and a simulation applying the developed checklist in K-IDES to similar types of high-rise buildings will be conducted to validate its accuracy. The final goal is to systemize an integrated risk management in a high-rise building against disasters for the purpose of recognizing vulnerable areas from the beginning of the design process and reinforcing it from potential threats after construction.

• Korean Journal of Metals and Materials
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• v.50 no.10
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• pp.729-734
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• 2012

This study investigated the effect of water absorption on the tensile properties of carbon-glass/epoxy hybrid composites at room temperature and $-30^{\circ}C$. To investigate the effect of the position of glass fabric in the hybrid composite on the tensile properties, the stacking pattern of the fiber fabrics for reinforcing was created in three different ways: (a) glass fabrics sandwiched between carbon fabrics, (b) carbon fabrics sandwiched between glass fabrics and (c) alternative layers of carbon and glass fabrics. They were manufactured by a vacuum-assisted resin transfer molding (VARTM) process. The results showed that there was surprisingly little difference in tensile strength at the two different temperatures with dry and wet conditions. However, the water absorption into the hybrid system affected the tensile properties of the hybrid composites at RT and $-30^{\circ}C$. When the glass fabrics were at the outermost layers, the hybrid composite had the lowest tensile properties. This is attributed to the fact that the composite had a relatively high water absorption rate.

• The Journal of Economics, Marketing and Management
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• v.5 no.1
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• pp.21-26
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• 2017

Purpose - This study extracts performance-reward factors based on the previous studies related to Herzberg's two-factor theory and performance-reward and proposes a research method to identify how these factors have an influence on task performance directly related to production performance and contextual performance that has an indirect influence. Research Design, Data, and Methodology - This study draws performance-reward factors through Focus Group Interview(FGI), classifies them into economic/uneconomic and direct/indirect factors, draws maintenance/improvement factors and unnecessary ones through IPA, and maximizes the effectiveness of performance-reward factors. Results - It also identifies how performance-reward factors have an influence on internal and external motives based on previous studies, classifies performance-reward factors into task performance and contextual performance and identifies the influence relationship between these, and proposes a research model to identify the roles of equity sensitivity based on equity theory. Conclusion - The findings from this study are expected to lay the groundwork for drawing various methods to reduce the turnover rate of employees and be important resources for reinforcing the competitiveness of businesses by classifying the performance -reward factors that may cause internal and external motives from the small and medium-sized manufacturing perspective and presenting methods to identify if these have an influence on task performance and contextual performance.

• Korean Journal of Legislative Studies
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• v.25 no.2
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• pp.69-101
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• 2019

The purpose of this study is to verify that voting behavior of congressmen can vary depending on the different candidate selection methods of political parties. Specifically, this paper examines whether congressmen elected through a primary tend to deviate from the party line vote in the floor voting, compared to those who did not. As a result, it was founded that congressmen who went through competition of the primary are more likely to defect from the party line vote than who did not. This empirical evidence suggests that if the introduction of the open primary system is further expanded in the future, it may lead to weakening of party cohesion and reinforcing lawmakers' autonomy.

• Journal of Electrochemical Science and Technology
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• v.14 no.4
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• pp.369-376
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• 2023

The quick-charging performance of SiO electrodes is evaluated with a focus on solid electrolyte interphase (SEI)-reinforcing effects. The study reveals that the incorporation of fluoroethylene carbonate (FEC) into the SiO electrode significantly reduced the electrode fatigue, which is from the the viscoelastic properties of the FEC-derived SEI film. The impact of FEC is attributed to its ability to minimize the mechanical failure of the electrode caused by additional electrolyte decomposition. This beneficial outcome arises from volumetric stain-tolerant characteristics of the FEC-derived SEI film, which limited exposure of the bare SiO surface during 0.5 C-rate cycling. Notably, FEC greatly improves Li deposition during quick-charge cycles following aging at 0.5 C-rate cycling due to its ability to maintain a strong electrical connection between active materials and the current collector, even after extended cycling. Given these findings, we assert that mitigating SEI layer deterioration, which compromises the electrode structure, is vital. Hence, enhancing the interfacial attributes of the SiO electrode becomes crucial for maintaining kinetic efficiency of battery system.

• Structural Engineering and Mechanics
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• v.88 no.1
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• pp.67-81
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• 2023

The reinforced concrete (RC) structures might need strengthening or upgradation due to adverse environmental conditions, design defects, modification requirements, and to prolong the expected lifespan. The RC beams have been efficiently strengthened using the near surface mounted (NSM) approach over the externally bonded reinforcing (EBR) system. In this study, the performance of RC beam elements strengthened with NSM-steel rebars was investigated using an experimental program and nonlinear finite element modeling (FEM). Nine medium-sized, rectangular cross-section RC beams total in number made up for the experimental evaluation. The beams strengthened with varying percentages of NSM reinforcement, and the number of grooves was assessed in four-point bending experiments up to failure. Based on the experimental evaluation, the load-displacement response, crack features, and failure modes of the strengthened beams were recorded and considered. According to the experimental findings, NSM steel greatly improved the flexural strength (up to about 84%) and stiffness of RC beams. The flexural response of the tested beams was simulated using a 3D non-linear finite element (FE) model. The findings of the experiments and the numerical analysis showed good agreement. The effect of the NSM groove and reinforcement on the structural response was then assessed parametrically.

• Computers and Concrete
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• v.33 no.2
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• pp.163-173
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• 2024

Fiber-reinforced polymers (FRP) have a proven strength enhancement capability when installed into Reinforced Concrete (RC) beams. The brittle failure of traditional FRP strengthening systems has attracted researchers to develop novel materials with improved strength and ductility properties. One such material is that known as polyethylene terephthalate (PET). This study presents a numerical investigation of the flexural behavior of reinforced concrete beams externally strengthened with PET-FRP systems. This material is distinguished by its large rupture strain, leading to an improvement in the ductility of the strengthened structural members compared to conventional FRPs. A three-dimensional (3-D) finite element (FE) model is developed in this study to predict the load-deflection response of a series of experimentally tested beams published in the literature. The numerical model incorporates constitutive material laws and bond-slip behavior between concrete and the strengthening system. Moreover, the validated model was applied in a parametric study to inspect the effect of concrete compressive strength, PET-FRP sheet length, and reinforcing steel bar diameter on the overall performance of concrete beams externally strengthened with PET-FRP.

• IMMUNE NETWORK
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• v.22 no.1
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• pp.7.1-7.20
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• 2022

Recently, there have been impressive advancements in understanding of the immune mechanisms underlying cutaneous inflammatory diseases. To understand these diseases on a deeper level and clarify the therapeutic targets more precisely, numerous studies including in vitro experiments, animal models, and clinical trials have been conducted. This has resulted in a paradigm shift from non-specific suppression of the immune system to selective, targeted immunotherapies. These approaches target the molecular pathways and cytokines responsible for generating inflammatory conditions and reinforcing feedback mechanisms to aggravate inflammation. Among the numerous types of skin inflammation, psoriasis and atopic dermatitis (AD) are common chronic cutaneous inflammatory diseases. Psoriasis is a IL-17-mediated disease driven by IL-23, while AD is predominantly mediated by Th2 immunity. Autoimmune bullous diseases are autoantibody-mediated blistering disorders, including pemphigus and bullous pemphigoid. Alopecia areata is an organ-specific autoimmune disease mediated by CD8⁺ T-cells that targets hair follicles. This review will give an updated, comprehensive summary of the pathophysiology and immune mechanisms of inflammatory skin diseases. Moreover, the therapeutic potential of current and upcoming immunotherapies will be discussed.