• Journal of the Computational Structural Engineering Institute of Korea
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• v.34 no.5
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• pp.279-286
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• 2021

In this study, we investigated the behavior characteristics of the L-type flange bolt connection, which is used to connect upper and lower flanges having L-type ring sections, by bolts. This connection is mainly used in domestic wind turbine structures, wherein it is a vital component as any imperfection could cause the collapse of the entire structural system. Therefore, understanding the behavior characteristics of the L-type flange bolt connection is imperative. In this study, the connection's response to external force was simulated using finite element (FE) analysis and the FE model was idealized to behave as a single L-type bolt flange. The variation in the bolt tension and the L-type flange stress were analyzed to understand the behavior characteristics of the connection. Moreover, the bolt-load function models proposed by Petersen, Schmidt/Neuper and VDI 2230, theoretically expressing a relation between bolt tension and external force, were compared to evaluate the suitability of the FE analysis and analyze the significant behavior characteristics of the connection. Furthermore, the changes in the bolt-load curve due to the variations in the partial dimensions of the L-type flange bolt connection were analyzed.

• Journal of Korean Foot and Ankle Society
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• v.23 no.1
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• pp.12-17
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• 2019

Purpose: This study examined the clinical outcomes and usefulness of triamcinolone acetonide (TA) injections as an option in the conservative treatment of patients with lateral malleolar bursitis of the ankle. Materials and Methods: A total of 27 patients (27 ankles), in whom TA injection had been performed between March 2016 and June 2017, were reviewed retrospectively. After the aspiration of fluid in the lateral malleolar bursal sac, 1 mL (40 mg) of TA was injected into the malleolar bursal sac. After the injection, the ankle was compressed with an elastic cohesive bandage for 2 to 4 weeks. The clinical outcomes and side effects were evaluated at the following time points: 2 weeks, 4 weeks, 3 months, 6 months, and 1 year after TA injection therapy. The responses to treatment were assessed according to the degree of fluctuation, shrinkage of the bursal sac, and soft tissue swelling. Results: The mean age was 62.1 years (range, 41~81 years); there were 19 males and 8 females. Complete resolution was observed in 26 patients (96.3%) after the first or second application of a TA injection, and a partial response was observed in 1 patient (3.7%) after the first TA injection. The physical component scores of Medical Outcomes Study 36-item Short-Form Health Survey improved from 71.1 to 76.0 at the last follow-up (p=0.001). Associated complications were 1 patient (3.7%) with skin atrophy and 3 patients (11.1%) with transient hyperglycemia in diabetes mellitus. Conclusion: TA injection is a useful and safe procedure for patients not responding to the usual conservative treatment of lateral malleolar bursitis of the ankle.

• Informatization Policy
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• v.26 no.1
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• pp.3-24
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• 2019

This study examined the trends and issues of social media campaign studies from three aspects-campaign strategy, institutional environment regulating the social media, and political effect. Then, this study performed an empirical analysis on the case of the 20th general election in order to discuss the political effect, which has been analyzed the least. Specifically, this study empirically examined the trends of candidates' participation in the twitter campaign, the partial mobilization and voter response, and the platform effect on the election results. The study examined all of the candidates' twitter accounts and traffic and found the following results.-first, the number of participants in the twitter campaign increased significantly compared to the 19th general election, and the campaign was dominated by only two political parties that had more power to mobilize resources; second, it was clearly identified that twitter is a partisan media. where specifically, those in the mainstream of the Democratic Party mobilized much more supporters; and lastly, the twitter campaign has a positive impact on the increase in the rate of votes and chances of winning the election. Particularly, the number of followers and the duration of activities were found statistically meaningful, proving that promotion of networking and social capital is more important in election campaigns.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.1
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• pp.79-86
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• 2021

In order to increase the probability of success in big data projects, quantified techniques are required to analyze the root cause of risks from complex causes and establish optimal countermeasures. To this end, this study measures risk factors and relationships through SNA analysis and presents a way to respond to risks based on them. In other words, it derives a dependency network matrix by utilizing the results of correlation analysis between risk groups in the big data projects presented in the preliminary study and performs SNA analysis. In order to derive the dependency network matrix, partial correlation is obtained from the correlation between the risk nodes, and activity dependencies are derived by node by calculating the correlation influence and correlation dependency, thereby producing the causal relationship between the risk nodes and the degree of influence between all nodes in correlation. Recognizing the root cause of risks from networks between risk factors derived through SNA between risk factors enables more optimized and efficient risk management. This study is the first to apply SNA analysis techniques in relation to risk management response, and the results of this study are significant in that it not only optimizes the sequence of risk management for major risks in relation to risk management in IT projects but also presents a new risk analysis technique for risk control.

• Journal of Korea Entertainment Industry Association
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• v.15 no.7
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• pp.169-180
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• 2021

The purpose of this study was to examine the effects of the activity constraints due to disability on subjective health status and daily life satisfaction among disabled, and mediating effects of subjective health status on the relationship between activity constraints due to disability and daily life satisfaction. For this purpose, the response data of 3,809 people who participated in the 5th year of the 2nd Wave of the Panel Survey of Employment for the Disabled (PSED) were used and analyzed. As a result, all sub-factors except for the degree of difficulties in hearing even when using hearing aids among activity constraints due to disability has a statistically significant negative effect on subjective health status, and all sub-factors has a significant negative effect on daily life satisfaction. And, subjective health status has a significant partial mediating effect on the relationship between all sub-factors except for the degree of difficulties in hearing even when using hearing aids among activity constraints due to disability and daily life satisfaction. Therefore, the level of activity constraint for the disabled should be reduced by providing systematic and differentiated customized rehabilitation programs that take into account the disability characteristics of the disabled, thereby improving the health level and social independence ability of the disabled. Furthermore, in order to improve the daily life satisfaction of the disabled, it is necessary to provide policy support such as the establishment of a community-based integrated support system for the disabled by linked rehabilitation program and health promotion program.

• Journal of Animal Science and Technology
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• v.64 no.4
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• pp.800-811
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• 2022

The integration of metabolomics and transcriptomics may elucidate the correlation between the genotypic and phenotypic patterns in organisms. In equine physiology, various metabolite levels vary during exercise, which may be correlated with a modified gene expression pattern of related genes. Integrated metabolomic and transcriptomic studies in horses have not been conducted to date. The objective of this study was to detect the effect of moderate exercise on the metabolomic and transcriptomic levels in horses. In this study, using nuclear magnetic resonance (NMR) spectroscopy, we analyzed the concentrations of metabolites in muscle and plasma; we also determined the gene expression patterns of branched chain (alpha) keto acid dehydrogenase kinase complex (BCKDK), which encodes the key regulatory enzymes in branched-chain amino acid (BCAA) catabolism, in two breeds of horses, Thoroughbred and Jeju, at different time intervals. The concentrations of metabolites in muscle and plasma were measured by ¹H NMR (nuclear magnetic resonance) spectroscopy, and the relative metabolite levels before and after exercise in the two samples were compared. Subsequently, multivariate data analysis based on the metabolic profiles was performed using orthogonal partial least square discriminant analysis (OPLS-DA), and variable important plots and t-test were used for basic statistical analysis. The stress-induced expression patterns of BCKDK genes in horse muscle-derived cells were examined using quantitative reverse transcription polymerase chain reaction (qPCR) to gain insight into the role of transcript in response to exercise stress. In this study, we found higher concentrations of aspartate, leucine, isoleucine, and lysine in the skeletal muscle of Jeju horses than in Thoroughbred horses. In plasma, compared with Jeju horses, Thoroughbred horses had higher levels of alanine and methionine before exercise; whereas post-exercise, lysine levels were increased. Gene expression analysis revealed a decreased expression level of BCKDK in the post-exercise period in Thoroughbred horses.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5B
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• pp.429-439
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• 2009

When Catastrophic extreme flood occurs due to dam break, the response time for flood warning is much shorter than for natural floods. Numerical models can be powerful tools to predict behaviors in flood wave propagation and to provide the information about the flooded area, wave front arrival time and water depth and so on. But flood wave propagation due to dam break can be a process of difficult mathematical characterization since the flood wave includes discontinuous flow and dry bed propagation. Nevertheless, a lot of numerical models using finite volume method have been recently developed to simulate flood inundation due to dam break. As Finite volume methods are based on the integral form of the conservation equations, finite volume model can easily capture discontinuous flows and shock wave. In this study the numerical model using Riemann approximate solvers and finite volume method applied to the conservative form for two-dimensional shallow water equation was developed. The MUSCL scheme with surface gradient method for reconstruction of conservation variables in continuity and momentum equations is used in the predictor-corrector procedure and the scheme is second order accurate both in space and time. The developed finite volume model is applied to 2D partial dam break flows and dam break flows with triangular bump and validated by comparing numerical solution with laboratory measurements data and other researcher's data.

• IMMUNE NETWORK
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• v.20 no.6
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• pp.48.1-48.11
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• 2020

Hyperprogressive disease (HPD) is a distinct pattern of progression characterized by acceleration of tumor growth after treatment with anti-PD-1/PD-L1 Abs. However, the immunological characteristics have not been fully elucidated in patients with HPD. We prospectively recruited patients with metastatic non-small cell lung cancer treated with anti-PD-1/PD-L1 Abs between April 2015 and April 2018, and collected peripheral blood before treatment and 7-days post-treatment. HPD was defined as ≥2-fold increase in both tumor growth kinetics and tumor growth rate between pre-treatment and post-treatment. Peripheral blood mononuclear cells were analyzed by multi-color flow cytometry to phenotype the immune cells. Of 115 patients, 19 (16.5%) developed HPD, 52 experienced durable clinical benefit (DCB; partial response or stable disease ≥6 months), and 44 experienced non-hyperprogressive progression (NHPD). Patients with HPD had significantly lower progression-free survival (p<0.001) and overall survival (p<0.001). When peripheral blood immune cells were examined, the pre-treatment frequency of CD39⁺ cells among CD8⁺ T cells was significantly higher in patients with HPD compared to those with NHPD, although it showed borderline significance to predict HPD. Other parameters regarding regulatory T cells or myeloid derived suppressor cells did not significantly differ among patient groups. Our findings suggest high pre-treatment frequency of CD39⁺CD8⁺ T cells might be a characteristic of HPD. Further investigations in a larger cohort are needed to confirm our results and better delineate the immune landscape of HPD.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.569-582
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• 2023

In recent years, the service life of major SOC facilities in south korea has exceeded 30 years, and rapid aging is expected within the next 10 years. This has led to a growing recognition of the need for proactive maintenance of these facilities. Consequently, there have been numerous research efforts to introduce smart inspection technologies into maintenance. However, the current system relies primarily on manpower for safety inspections and diagnostics, and on-site surveys rely on visual inspections. Manpower inspections can be time-consuming, and subjective errors may occur during result analysis. In the case of tunnels, there are disadvantages, such as the loss of social overhead capital due to partial closures during inspections. Therefore, institutionalizing smart safety inspections is essential, considering specific measures like using advanced equipment and updating qualifications for experts. Furthermore, it is necessary to verify and validate safety inspection results using advanced equipment before instituting changes. This could be achieved through national-level official research programs and the operation of verification and validation institutions. If smart inspection technology is introduced into maintenance, routine inspections of SOC facilities, such as tunnels, will become feasible. As a result, maintenance technology capable of early detection and proactive response to safety incidents caused by changes in facility conditions is anticipated.

• Journal of Gastric Cancer
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• v.8 no.1
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• pp.40-46
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• 2008

Purpose: We wanted to evaluate the efficacy and toxicity of modified FOLFOX-6 chemotherapy for treating recurrent or inoperable gastric cancer patients. Materials and Methods: From April 2006 to August 2007, 35 patients with recurrent gastric cancer after curative resection and 43 patients with inoperable gastric cancer underwent chemotherapy, and the results were retrospectively investigated. Results: 78 patients were assessable for response and toxicity, and they underwent an average of 7.1 cycles of chemotherapy. The response was evaluated according to the RECIST criteria. 11 partial responses (14.1%), 35 cases of stable disease (44.9%), and 32 cases of progressive disease (41%) were observed. The median time to progression was 6 months, and the average overall survival was 13 months. CTCAE grade 1 or 2 anemia (52.6%) was the most prevalent toxicity. Other common toxicities included thrombocytopenia (17.9%) and peripheral neuropathy (30.8%). There were 13 changes in the chemotherapy regimen to S1-cisplatin due to disease progression, but only an average of 1.76 cycles of S1-cisplatin were delivered due to severe toxicities and poor compliance. Conclusion: Acceptable efficacy and toxicity were seen as 59% of the patients showed non-progression, and no grade 3 or 4 toxicities were observed. In conclusion, the modified FOLFOX-6 chemotherapy is considered to be the proper 1st-line choice as a palliative treatment for recurrent or inoperable gastric cancer patients.