• Journal of The Korean Astronomical Society
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• v.53 no.4
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• pp.87-98
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• 2020

The Korea Astronomy and Space Science Institute (KASI) has been developing a next-generation coronagraph (NGC) in cooperation with NASA to measure the coronal electron density, temperature, and speed simultaneously, using four different optical filters around 400 nm. KASI organized an expedition to demonstrate the coronagraph measurement scheme and the instrumental technology during the 2017 total solar eclipse (TSE) across the USA. The observation site was in Jackson Hole, Wyoming, USA. We built an eclipse observation system, the Diagnostic Coronal Experiment (DICE), composed of two identical telescopes to improve the signal-to-noise ratio. The observation was conducted at four wavelengths and three linear polarization directions in the limited total eclipse time of about 140 seconds. We successfully obtained polarization data for the corona but we were not able to obtain information on the coronal electron temperature and speed due to the low signal-to-noise ratio of the optical system and strong emission from prominences located at the western limb. In this study, we report the development of DICE and the observation results from the eclipse expedition. TSE observation and analysis with our self-developed instrument showed that a coronagraph needs to be designed carefully to achieve its scientific purpose. We gained valuable experience for future follow-up NASA-KASI joint missions: the Balloon-borne Investigation of the Temperature and Speed of Electrons in the Corona (BITSE) and the COronal Diagnostic EXperiment (CODEX).

• Biomedical Science Letters
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• v.24 no.2
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• pp.134-137
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• 2018

S100A8 and S100A9 are involved in pathogenesis of cancer by induction or inhibition of cancer as well as inflammation. In this study, we investigated the association of S100A8 and S100A9 with pathogenesis of leukemia using human monocytic leukemia cells, THP-1. The expression of TLR4, which is a known receptor of S100A8 and S100A9, was examined by using flow cytometry and Western blotting. THP-1 cells have high surface and cytosol expression of TLR4. S100A8 and S100A9 suppressed the cell survival, and this suppression was found to be associated with apoptosis because they increased the number of apoptotic cells in a dose- and a time-dependent manners. However, S100A8 and S100A9 had no effect on the survival and apoptosis of monocytes isolated from the peripheral blood. We next examined the apoptotic effect of lipopolysaccharide (LPS) and monophosphoryl lipid A (MPLA), which are other ligands of TLR4, in THP-1 cells. Lipopolysaccharide had no effect on cell survival, but MPLA is effective on the cell apoptosis. These results suggest that S100A8 and S100A9 may regulate leukemia cell survival via TLR4, which is an essential receptor in the pro-apoptotic mechanism induced by S100A8 and S100A9. These findings may shed light on development of a possible therapeutic drug for leukemia treatment.

• Smart Structures and Systems
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• v.14 no.6
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• pp.1031-1054
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• 2014

Real-time hybrid simulation (RTHS) of a stacked wood shear wall retrofitted with a rate-dependent seismic energy dissipation device (viscous damper) was conducted at the newly constructed Structural Engineering Laboratory at the University of Alabama. This paper describes the implementation process of the RTHS focusing on the controller scheme development. An incremental approach was adopted starting from a controller for the conventional slow pseudodynamic hybrid simulation and evolving to the one applicable for RTHS. Both benchmark-scale and full-scale tests are discussed to provide a roadmap for future RTHS implementation at different laboratories and/or on different structural systems. The developed RTHS controller was applied to study the effect of a rate-dependent energy dissipation device on the seismic performance of a multi-story wood shear wall system. The test specimen, setup, program and results are presented with emphasis given to inter-story drift response. At 100% DBE the RTHS showed that the multi-story shear wall with the damper had 32% less inter-story drift and was noticeably less damaged than its un-damped specimen counterpart.

• The Korean Journal of Rehabilitation Nursing
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• v.10 no.2
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• pp.141-146
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• 2007

Purpose: This study was conducted to estimate the prevalence rate, and related factors,of fatty liver in male industrial workers. Method: Fatty liver was diagnosed using ultrasonography. The data for abdominal ultrasonography, BMI, smoking, alcohol drinking, exercise, liver enzymes, and lipid profiles were collected in 4,604 male who were examined with a health screening program in 2005. Prevalence rate and associated factors of fatty liver were analyzed using SPSS v. 12.0. Results: Overall prevalence of fatty liver was 34.1% and higher in the 30-39 year male group. Age, body mass index(BMI), hypertriglyceridemia, hypercholesterolemia, HDL cholesterol, r-GTP level were independently associated factors with presence of fatty liver in logistic regression analysis. Conclusion: The prevalence of fatty liver and tendency of associated factors were similar to those in the western world. To prevent development of this hepatic disorder, which may result in end-stage liver disease, risk factors such as obesity and dyslipidemia must be monitored and controlled within normal levels. The results of this study suggested maintenance of a healthy lifestyle, including diet, exercise, and behavioral change, as fundamental rehabilitation nursing implications.

• Computers and Concrete
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• v.13 no.6
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• pp.709-737
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• 2014

Fibre-reinforced self-compacting concrete (FRSCC) is a high-performance building material that combines positive aspects of fresh properties of self-compacting concrete (SCC) with improved characteristics of hardened concrete as a result of fibre addition. To produce SCC, either the constituent materials or the corresponding mix proportions may notably differ from the conventional concrete (CC). These modifications besides enhance the concrete fresh properties affect the hardened properties of the concrete. Therefore, it is vital to investigate whether all the assumed hypotheses about CC are also valid for SCC structures. In the present paper, the experimental results of short-term flexural load tests on eight reinforced SCC and FRSCC specimens slabs are presented. For this purpose, four SCC mixes - two plain SCC, two steel, two polypropylene, and two hybrid FRSCC slab specimens - are considered in the test program. The tests are conducted to study the development of SCC and FRSCC flexural cracking under increasing short-term loads from first cracking through to flexural failure. The achieved experimental results give the SCC and FRSCC slabs bond shear stresses for short-term crack width calculation. Therefore, the adopted bond shear stress for each mix slab is presented in this study. Crack width, crack patterns, deflections at mid-span, steel strains and concrete surface strains at the steel levels were recorded at each load increment in the post-cracking range.

• Korean Journal of Childcare and Education
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• v.1 no.1
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• pp.37-58
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• 2005

The purpose of this study was to examine whether or not the use of number-related fairy tales had any effects on young children's mathematical inquiry skills in a bid to help facilitate their development of mathematical capabilities. The subjects in this study were 30 preschoolers who were four years old in Western age and attended G kindergarten in Jung-gu, Ulsan. The instrument used to assess their mathematical inquiry skills was Choi Hye-jin(2003)'s Preschooler Math Capability Inventory. The collected data wee analyzed with SPSS Win 11.5 program, and analysis of covariance was utilized. The findings of the study were as follows: The application of number-related fairy tales turned out to be effective in developing the young children's abilities to figure out the regularity of things, conception of number, geometrical abilities, measurement abilities and mathematical inquiry skills of the preschoolers. The above-mentioned findings suggested that the application of number-related fairy tales was one of good teaching methods to step up the development of young children's mathematical inquiry skills. Specifically, that could inner motivation to preschoolers in mathematical contexts and take their problem-solving skills to another level.

• The Journal of Korean Obstetrics and Gynecology
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• v.23 no.3
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• pp.123-138
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• 2010

Purpose: The purpose of this study is to identify the real condition of urinary incontinence(UI), interstitial cystitis(IC), atrophic viginitis(AV) for elderly women and analyze the cognition of traditional korean medicine(TKM) for them. Methods: We utilized questionnaire from May to June, 2010. Questionnaires were taken from 125 women using senior welfare center and nursing home, aged over 65 up to 92. The data were analyzed by $X^2$-test using SPSS/PC ver 18.0 program. Results: The prevalences of UI, IC and AV symptoms were 50.4%, 40.8%, 56%, respectively. The average I-QoL score for UI was $82.62{\pm}21.16$, and the average ICSI score for IC was $8.16{\pm}2.50$. After adjustment for each of the variables considered in this study, alcohol was associated with UI and age, BMI(body mass index) were associated with IC. Most of respondents have no experience(94.4%) or don't know (79.2%) about TKM for UI, IC and AV. 44 women(37.3%) indicated that they weren't willing to use TKM for UI, IC and AV. Reasons for not taking TKM were because of 'no knowledge of TKM(34.1%)' and 'more accustomed to western treatment(34.1%)'. Conclusion: Although the prevalence of UI, IC, AV for elderly women was high, the actual percentage of treatment for these diseases was low, furthermore, patients were not aware of TKM and had very few experiences of TKM for these diseases. The development and increased promotion about TKM program for elderly women's urogenital diseases is needed.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.329-334
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• 2010

Escherichia coli O157:H7 causes hemolytic uremic syndrome and hemorrhagic colitis in humans. The objectives of this study were to produce monoclonal antibody(MAb) against E. coli O157:H7 and to develop an enzyme linked immunosorbent assay(ELISA) for the rapid detection of E. coli O157:H7 in agri-stockbreeding. The characterization of MAb produced from hybridoma cell (HKEC 4G8-5) was validated by ELISA and Western blot. The produced MAb was specific to E. coli O157:H7 and showed weak cross-reaction to Staphylococcus aureus. The detection limit of ELISA based on 4G8-5 MAb was $10^5\;cell/mL$. Although the ELISA could not detect E. coli O157:H7 in the meat and sprout samples inoculated with $1{\times}10^1\;cell$/10 g without enrichment, the same samples after enrichment for 6 hr were confirmed to be positive by ELISA. These results indicated that the ELISA combined with short enrichment (6 hr) is useful tool for rapid screening of E. coli O157:H7 in various samples.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.2
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• pp.96-107
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• 2016

This study is an attempt to trace the origins of Korean botanical gardens prior to the construction of the botanical garden in Changgyeonggung Palace. We trace the time period during which Korean intellectuals first understood and appropriated botanical gardens based on accounts found in travel journals. These were written by members of delegations sent to Japan, Russia, and Great Britain and by students who had studied abroad, such as Tchi-Ho Yun and Kil-Chun Yu, during the open port period from 1876 to 1910. This study shows that the term "botanical garden" did not appear in any of the travel journals and the delegations did not show much interest in them until the 1880s. Japan had planned to introduce the different types of botanical gardens to the delegations from the Joseon Dynasty, but the delegations left no official records or related accounts regarding their visits. In contrast, members of delegations who were sent to Russia, Europe, and America after the 1890s began to pay attention to botanical gardens. They considered botanical gardens as a representative and essential part of Western culture and attempted to introduce them in Korea as essential tools for academic development as well as for enlightenment. Although many Korean intellectuals' opinions about the necessity of a botanical garden did not actually lead to its construction during the open port period, such a movement was significant in that it strengthened the botanical garden's image as a symbol of civilization. Apart from tracing the origins of the botanical gardens in Korea, this study serves as fundamental research material for understanding the establishment of the Changgyeongwon Botanical Garden in 1909.

• Korean Journal of Plant Taxonomy
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• v.50 no.2
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• pp.154-165
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• 2020

Coastal regions are experiencing habitat changes due to coastal development and global warming. To estimate the future distribution of coastal plants on the Korean Peninsula due to climate change, the potential distribution of ten species of coastal plants was analyzed using the MaxEnt program. The study covered the eastern, western, and southern coastal areas of the Korean Peninsula. We used the distributional data of coastal plants of the East Asian region and the 19 climate variables of WorldClim 2.0. The future potential distribution was estimated using future climate variables projected from three general circulation models (CCSM4, MIROC-ESM, and MPI-ESM-LR), four representative concentration pathways (2.5, 4.5, 6.0, and 8.5), and two time periods (2050 and 2070). The annual mean temperature influenced the estimation of the potential distribution the most. Under predicted future distribution scenarios, Lathyrus japonicus, Glehnia littoralis, Calystegia soldanella, Vitex rotundifolia, Scutellaria strigillosa, Linaria japonica, and Ixeris repens are expected to show contracted distributions, whereas the distribution of Cnidium japonicum is expected to expand. Two species, Salsola komarovii and Carex kobomugi, are predicted to show similar distributions in the future compared to those in the present. The average potential distribution in the future suggests that the effects of climate change will be greater in the west and the south coastal regions than in the east coastal region. These results will be useful baseline data to establish a conservation strategy for coastal plants.