• Proceedings of the Korean Magnestics Society Conference
• /
• 2013.12a
• /
• pp.113-113
• /
• 2013

• Proceedings of the Korean Magnestics Society Conference
• /
• 2013.12a
• /
• pp.123-123
• /
• 2013

• Proceedings of the Korean Magnestics Society Conference
• /
• 2014.11a
• /
• pp.148-148
• /
• 2014

• Journal of Korean Neurosurgical Society
• /
• v.66 no.5
• /
• pp.605-608
• /
• 2023

• Journal of applied mathematics & informatics
• /
• v.22 no.1_2
• /
• pp.351-360
• /
• 2006

In this paper, we develop an inexact-Newton method for solving nonsmooth operator equations in infinite-dimensional spaces. The linear convergence and superlinear convergence of inexact-Newton method under some conditions are shown. Then, we characterize the order of convergence in terms of the rate of convergence of the relative residuals. The present inexact-Newton method could be viewed as the extensions of previous ones with same convergent results in finite-dimensional spaces.

• Korean Circulation Journal
• /
• v.53 no.4
• /
• pp.254-267
• /
• 2023

Background and Objectives: Although the shortage of donor is a common problem worldwide, a significant portion of unutilized hearts are classified as marginal donor (MD) hearts. However, research on the correlation between the MD and the prognosis of heart transplantation (HTx) is lacking. This study was conducted to investigate the clinical impact of MD in HTx. Methods: Consecutive 73 HTxs during 2014 and 2021 in a tertiary hospital were analyzed. MD was defined as follows; a donor age >55 years, left ventricular ejection fraction <50%, cold ischemic time >240 minutes, or significant cardiac structural problems. Preoperative characteristics and postoperative hemodynamic data, primary graft dysfunction (PGD), and the survival rate were analyzed. Risk stratification by Index for Mortality Prediction after Cardiac Transplantation (IMPACT) score was performed to examine the outcomes according to the recipient state. Each group was sub-divided into 2 risk groups according to the IMPACT score (low <10 vs. high ≥10). Results: A total of 32 (43.8%) patients received an organ from MDs. Extracorporeal membrane oxygenation was more frequent in the non-MD group (34.4% vs. 70.7, p=0.007) There was no significant difference in PGD, 30-day mortality and long-term survival between groups. In the subgroup analysis, early outcomes did not differ between low- and high-risk groups. However, the long-term survival was better in the low-risk group (p=0.01). Conclusions: The outcomes of MD group were not significantly different from non-MD group. Particularly, in low-risk recipient, the MD group showed excellent early and long-term outcomes. These results suggest the usability of selected MD hearts without increasing adverse events.

• Journal of Industrial and Engineering Chemistry
• /
• v.68
• /
• pp.117-123
• /
• 2018

Recently, aqueous method has attracted lots of attention because it enables the solution-processed metal oxide thin film with high electrical properties in low temperature fabrication condition to various flexible devices. Focusing the development of aqueous route, many researchers are only focused on metal oxide materials. However, for expansive application of the aqueous-based metal oxide films, the systematic study of performance change with process variables for the development of aqueous-based metal oxide insulator film is urgently required. Here, we propose importance of process variables to achieve high electrical-performance metal oxide insulator based on the aqueous method. We found that the significant process variables including precursor solution temperature and humidity during the spincoating process strongly affect chemical, physical, and electrical properties of $AlO_x$ insulators. Through the optimization of significant variables in process, an $AlO_x$ insulator with a leakage current value approximately $10^5$ times smaller and a breakdown voltage value approximately 2-3 times greater than un-optimized $AlO_x$ was realized. Finally, by introducing the optimized $AlO_x$ insulators to solutionprocessed $InO_x$ TFTs, we successfully achieved $InO_x/AlO_x$ TFTs with remarkably high average field-effect mobility of ${\sim}52cm^2V^{-1}\;s^{-1}$ and on/off current ratio of 106 at fabrication temperature of $250^{\circ}C$.

• Journal of Information Science Theory and Practice
• /
• v.10 no.spc
• /
• pp.1-11
• /
• 2022

As data-based research activities and outcomes increase and ontact or non-face-to-face activities become common, the demand for easy utilization of resources, tools, functions, and easily accessible information required for research in the R&D sector has increased accordingly. With the rapid increase in the demand for collaborative research based on online platforms, research support institutions strive to provide venues for research activities that merge various information and functions. ScienceON, an integrated science & technology (S&T) knowledge infrastructure service developed and operated by the Korea Institute of S&T Information (KISTI), supports open collaboration by connecting and merging all the information, functions, and infrastructure required for research activities. This paper describes the online research activity support tool provided by ScienceON and the remarkable results achieved through this activity. Specifically, the excellent creation of the following flow of meta-material research activities in the ontact space is elucidated. First, the papers required for a meta-material analysis are retrieved, virtual simulation is conducted with the experimental data extracted from the papers, and research data are accumulated. ScienceON's tools for supporting ontact research activity will play a role as an important service in the era of digital transformation and open science.

• Journal of Korean Institute of Industrial Engineers
• /
• v.42 no.1
• /
• pp.1-19
• /
• 2016

Recently, the emergence of smartphone foster the technological convergence. This convergence no longer takes place within technologies only. Rather, convergence phenomena happen as a form of embodied services. However, previous research on convergence has been subject to the technology-oriented studies, including suggesting patent-based indexes or analyzing technological characteristics. However, investigating technology-service convergence is critical since most of new smart services are technology-based convergence services. Therefore, we analyze the pattern of technology-service convergence which occurs in the smartphone application services. We divided the smatphone application services into four categories, and employ a network analysis to represent the convergence phenomena of each category. Our study is expected to provide meaningful implication in new service development practice.

• The Korean Journal of Physiology and Pharmacology
• /
• v.19 no.5
• /
• pp.451-460
• /
• 2015

Sirtuin 1 (SIRT1) is a mammalian $NAD^+$-dependent protein deacetylase that regulates cellular metabolism and inflammatory response. The organ-specific deletion of SIRT1 induces local inflammation and insulin resistance in dietary and genetic obesity. Macrophage-mediated inflammation contributes to insulin resistance and metabolic syndrome, however, the macrophage-specific SIRT1 function in the context of obesity is largely unknown. C57/BL6 wild type (WT) or myeloid-specific SIRT1 knockout (KO) mice were fed a high-fat diet (HFD) or normal diet (ND) for 12 weeks. Metabolic parameters and markers of hepatic steatosis and inflammation in liver were compared in WT and KO mice. SIRT1 deletion enhanced HFD-induced changes on body and liver weight gain, and increased glucose and insulin resistance. In liver, SIRT1 deletion increased the acetylation, and enhanced HFD-induced nuclear translocation of nuclear factor kappa B (NF-${\kappa}B$), hepatic inflammation and macrophage infiltration. HFD-fed KO mice showed severe hepatic steatosis by activating lipogenic pathway through sterol regulatory element-binding protein 1 (SREBP-1), and hepatic fibrogenesis, as indicated by induction of connective tissue growth factor (CTGF), alpha-smooth muscle actin (${\alpha}$-SMA), and collagen secretion. Myeloid-specific deletion of SIRT1 stimulates obesity-induced inflammation and increases the risk of hepatic fibrosis. Targeted induction of macrophage SIRT1 may be a good therapy for alleviating inflammation-associated metabolic syndrome.