• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.3
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• pp.274-280
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• 2016

Hinge driving type holding and release mechanism based on the burn wire release for application of cubesat is main payload of STEP Cube Lab. (Cube Laboratory for Space Technology Experimental Project) to be launched at 2015. It has high constraint force, low shock level as well as surmounting drawbacks of conventional nichrome burn wire release method that has relatively low constraint force and system complexity for application of multi-deployable systems. In this paper, we have proposed a flight model of holding and release mechanism for the verification of the constraint force and deployment status signal acquisition. To validate the effectiveness of the flight model, launch and on-orbit environment verification test have been performed.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.4
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• pp.299-310
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• 2020

Alzheimer's disease (AD) is a multi-faceted neurodegenerative disease. Thus, current therapeutic strategies require multitarget-drug combinations to treat or prevent the disease. At the present time, single drugs have proven to be inadequate in terms of addressing the multifactorial pathology of AD, and multitarget-directed drug design has not been successful. Based on these points of views, it is judged that combinatorial drug therapies that target several pathogenic factors may offer more attractive therapeutic options. Thus, we explored that the combination therapy with lower doses of cilostazol and aripiprazole with add-on donepezil (CAD) might have potential in the pathogenesis of AD. In the present study, we found the superior efficacies of donepezil add-on with combinatorial mixture of cilostazol plus aripiprazole in modulation of expression of AD-relevant genes: Aβ accumulation, GSK-3β, P300, acetylated tau, phosphorylated-tau levels, and activation of α-secretase/ADAM 10 through SIRT1 activation in the N2a Swe cells expressing human APP Swedish mutation (N2a Swe cells). We also assessed that CAD synergistically raised acetylcholine release and choline acetyltransferase (CHAT) expression that were declined by increased β-amyloid level in the activated N2a Swe cells. Consequently, CAD treatment synergistically increased neurite elongation and improved cell viability through activations of PI3K, BDNF, β-catenin and α7-nicotinic cholinergic receptors in neuronal cells in the presence of Aβ_1-42. This work endorses the possibility for efficient treatment of AD by supporting the synergistic therapeutic potential of donepezil add-on therapy in combination with lower doses of cilostazol and aripiprazole.

• The Korean Journal of Applied Statistics
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• v.21 no.6
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• pp.923-932
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• 2008

We are likely to face complex multivariate data which can be characterized by having a non-trivial correlation structure. For instance, omitted covariates may simultaneously affect more than one count in clustered data; hence, the modeling of the correlation structure is important for the efficiency of the estimator and the computation of correct standard errors, i.e., valid inference. A standard way to insert dependence among counts is to assume that they share some common unobservable variables. For this assumption, we fitted correlated random effect models considering multilevel model. Estimation was carried out by adopting the semiparametric approach through a finite mixture EM algorithm without parametric assumptions upon the random coefficients distribution.

• Tribology and Lubricants
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• v.32 no.4
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• pp.125-131
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• 2016

In recent years, thick ta-C coating has attracted considerable interest owing to its existing and potential commercial importance in applications such as automobile accessories, drills, and gears. The thickness of the ta-C coating is an important parameter in these applications. However, the biggest problems are achieving efficient coating and uniformity over a large area with high-speed deposition. Feasibility is confirmed for the ta-C coating thickness of up to 9.0 µm (coating speed: 3.0 µm/h, fixed substrate) using a single FCVA cathode. The thickness was determined using multiple coating cycles that were controlled using substrate temperature and residual stresses. In the present research, we have designed a coating system using FCVA plasma and produced enhanced thick ta-C coating. The system uses a specialized magnetic field configuration with stabilized DC arc plasma discharge during deposition. To achieve quality that is acceptable for use in automobile accessories, the magnetic field, T-type filters, and 10 pieces of a multi-cathode are used to demonstrate the deposition of the thick ta-C coating. The results of coating performance indicate that uniformity is ±7.6 , deposited area is 400 mm, and the thickness of the ta-C coating is up to 5.0 µm (coating speed: 0.3 µm/h, revolution and rotation). The hardness of the coating ranges from 30 to 59 GPa, and the adhesion strength level (HF1) ranges from 20 to 60 N, depending on the ta-C coating.

• Journal of Veterinary Clinics
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• v.30 no.4
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• pp.273-277
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• 2013

This study was performed to compare clinical and diagnostic imaging features between asymptomatic and symptomatic extrahepatic portosystemic shunts in dogs. The data of thirty patients diagnosed with extrahepatic PSS by multi-detector CT were reviewed, and the dogs were divided into asymptomatic (9/30) and symptomatic (21/30) groups. Signalments, hematologic results, liver size, morphologic classifications and main portal vein to abdominal aortic ratio (PV/AO) at the porta hepatis level from CT images were evaluated in two groups. Shih-tzu (5/9) was the most frequent breed in asymptomatic group, and various breeds were presented in symptomatic group. Mean age of asymptomatic group ($9.2{\pm}3.2$ years) was significantly higher than that of symptomatic group ($4.5{\pm}3.2$ years). The most morphologic form of shunt vessel was the splenophrenic shunt (16/30). PV/AO of asymptomatic group ($1.1{\pm}0.19$) was significantly higher than the values of symptomatic group ($0.55{\pm}0.19$). Clinical signs, hematologic results and diagnostic imaging findings of asymptomatic PSS are too nonspecific to suspect PSS. Therefore, considering of patient's age and CT examination with application of PV/AO ratio could be useful for the diagnosis of asymptomatic PSS.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.4
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• pp.586-591
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• 2010

Chemokine and Growth Factor are major mediumtors of immuno-inflammatory pathway. The purpose of this study is to investigate whether productions of Chemokine and Growth Factor in lipopolysaccharide (LPS)-induced mouse macrophage RAW 264.7 cells are modulated by Gallic acid (GA), which is easily founded in tannin-containing natural materials such as red wine, green tea, grape juice, and Corni Fructus. Productions of Chemokine and Growth Factor were analyzed by High-throughput Multiplex Bead based Assay with Bio-plex Suspension Array System based on $xMAP^{(R)}$ (multi-analyte profiling beads) technology. At first, cell culture supernatant was obtained after treatment with LPS and GA for 24 hour. Then, the antibody-conjugated beads were added and incubated for 30 minutes. After incubation, detection antibody was added and incubated for 30 minutes. And Strepavidin-conjugated Phycoerythrin (SAPE) was added. After incubation for 30 minutes, the level of SAPE fluorescence was analyzed on Bio-plex Suspension Array System. Based on fluorescence intensity, concentrations of Chemokine and Growth Factor were determined. The results of the experiment are as follows. GA significantly inhibited the production of interferon-inducible protein (IP)-10, keratinocyte-derived chemokine(KC), and vascular endothelial growth factor (VEGF) in LPS-induced RAW 264.7 cells at the concentration of 25, 50, 100, 200 uM (p<0.05). GA significantly inhibited the production of monocyte chemoattractant protein-1(MCP-1) and macrophage-colony stimulating factor(M-CSF) in LPS-induced RAW 264.7 cells at the concentration of 50, 100, 200 uM (p<0.05). GA diminished the production of granulocyte macrophage-colony stimulating factor (GM-CSF) in LPS-induced RAW 264.7 cells. But GA did not show the inhibitory effect on the production of leukemia inhibitory factor (LIP) and macrophage inflammatory protein (MIP)-2 in LPS-induced RAW 264.7 cells. These results suggest that GA has the immuno-modulating activity related with its inhibitory effects on the production of IP-10, KC, MCP-1, VEGF, and M-CSF in LPS-induced macrophages.

• Journal of Preventive Medicine and Public Health
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• v.40 no.3
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• pp.233-238
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• 2007

Objectives : We aimed to assess the relationship between long-term exposure to air pollution and lung cancer in the Republic of Korea. Methods : Using the Annual Report of Ambient Air Quality in Korea, Annual Report of National Cancer Registration, and Annual Report on the Cause of Death Statistics, we calculated the standardized mortality ratio (SMR) and standardized incidence ratio (SIR) of lung cancer for both sexes in 74 areas from 7 Korean metropolitan cities. We performed random intercept, Poisson regression using empirical Bayes method. Results : Both SMRs and SIRs in the 7 metropolitan cities were higher in women than in men. Mean SIRs were 99.0 for males and 107.0 for females. The association between $PM_{10}$ and lung cancer risk differed according to gender. $PM_{10}$ was not associated with the risk of lung cancer in males, but both incidence and mortality of lung cancer were positively associated with $PM_{10}$ in females. The estimated percentage increases in the rate of female lung cancer mortality and incidence were 27% and 65% at the highest $PM_{10}$ category $({\geq}70\;{\mu}g/m^3)$, compared to the referent category $({\geq}50\;{\mu}g/m^3)$. Conclusions : Long-term exposure to $PM_{10}$ was significantly associated with female lung cancer incidence in 7 Korean metropolitan cities. Further study is undergoing to estimate the relative risk of $PM_{10}$ using multi-level analysis for controlling individual and regional confounders such as smoking and socioeconomic position.

• Journal of the Korean Society of Radiology
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• v.5 no.1
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• pp.27-35
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• 2011

The purpose of this study is to examine factors that affect the bone mineral density of pre-menopause women by using the dual energy x-ray absorptionmetry, ultimately contributing to preventing women's osteoporosis that tends to be aggravated since menopause. Out of the subjects, 20.2% were suffering osteopenia. Age was found most important in estimating the level of bone mineral density. Meanwhile, the older women were, the significantly lower their bone mineral density was. It was found that taking exercise has a more positive effect on boss mineral density than not taking. Exercising in a suitable amount was helping women keep their bone mineral density better. Preferring meat to vegetarian diets were significantly affecting women's bone mineral density. Meanwhile, it was found that the shorter menstrual cycle is, the significantly lower bone mineral density is. A multi=regression analysis of bone mineral density and its related factors showed that the older women were, the significantly lower their bone mineral density was. In other words, age was found as the most risk factor of osteoporosis.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.2
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• pp.287-298
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• 1989

A numerical work was performed to study the flow behaviors of the open channel type flow with its geometric boundary conditions being similar to that of the Multi-Stage-Flash evaporator with and without a baffle. For the analysis, two-dimensional steady turbulent flow was assumed and the widely known k-.epsilon. turbulence model was usded. SIMPLE algorithm and the power difference scheme were used for the numerical approach. Numerical results generally agree with the previous experimental results though there are some uncertainties at far downstream and near the free surface due to the three dimensionality of the flow and surface waves. Without a baffle, the flow has basically the shape of the submerged plane wall jet with its upper boundary at downstream being sharply curved toward the free surface. For the flow with a baffle, recirculation flow patterns are observed at the upper inlet portion and at the backside of the baffle. For the case without a baffle, it was also confirmed that the ratio between the liquid level and the gate opening height is the most important parameter to determine the flow behavior.

• Journal of Fashion Business
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• v.1 no.1
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• pp.27-42
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• 1997

The Korean fashion industry is composed of originality, technique and business management. It is going to be the main role in the living and cultural industry in 21th century as a strategic advanced industry. On the other hand, more than 15,000 persons who majored in correlated fashion are graduated from universities, colleges, and fashion schools every year. But professional and competent persons specialized in clothings are very insufficient. So cultivation of the talented for fashion industry must be suitablely and differentially carried out, according to regional distinction or characteristics of each university, college level, institute and so on. At same time, it is for the subdivided professional educations in fashion field, also. Education institutions related fashion have to practice not only theory but also field-oriented education of fashion industry. The fashion enterprise must invest resolutely in reeducations for incoming and reading employees, too. Briefing the program of cultivating the competent as follows : (1) The execution of certification programes based on professional job series. (2) Cultivation of the talent by cooperation of industry and educational field. (3) Upbringing the specialists who have both abilities of foreign language and living cultural profession. (4) Establishment of a base oriented north-east Asia as the central fashion business. (5) Efficient using of multi-media. (6) Innovation of technology. (7) Preferential treatment of skilled labors apparel industry field. (8) Establishment of the Korean Society of Fashion Business for a bridge of industrial-educational complex and government, for cultivation of the talent. The programs of 'cultivation of the talent' must be differed from to whom', 'what', 'how long'. But the commonness in all is to need the stimulative education and creativity. Through it, 'what and how think' and 'how application' to all directions is acquired.