• Proceedings of the KAIS Fall Conference
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• 2011.12a
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• pp.196-199
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• 2011

In this study we synthesized mesoporous carbon supported CuO by using mesoporous silica i.e. SBA-15 as the template and cupric nitrate trihydrate ($Cu(NO_3)_23H_2O$)as copper source. The porous CuO was characterized with XRD, TGA, SEM and BET. The result reveals porous CuO has good crystal structure with uniform size of spherical crystal particles. The surface are a ($S_{BET}$) of porous CuO was found to be $153.46m^2g^{-1}$ with a total pore volume ($V_p$)of$0.1516cm^3g^{-1}$ and average pore size of 3.9 nm which was much higher than that of commercial CuO ($S_{BET}$, $7.6m^2g^{-1}$; $V_p$, $0.01cm^3g^{-1}$). The obtained porous CuO was studied for adsorption of $CO_2$and the maximum $CO_2$ adsorption capacity was found to be 67.5 mg/g of the sorbent at $25^{\circ}C$.

• Journal of Digital Convergence
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• v.17 no.10
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• pp.127-139
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• 2019

This study aims to explore the impressive experiences of university students on YouTube media and to find ways to improve personal media as useful consumer information. 44 university students were selected, and data on the experience of using YouTube were collected and analyzed by applying the critical incident technique. As a result, the positive responses to personal media were derived from 'enhancing C2C information capabilities', 'consumer-centric usability', 'attractive information creators', 'a sense of the sameness', and 'fresh and entertaining information'. Negative responses were derived from 'spreading of harmful information', 'distrust in information creators', 'inducing excessive advertising and impulse buying', 'media addiction' and 'relative deprivation'. In addition, improvement of the personal media has been suggested. This study has differentiation and significance as a qualitative data for understanding consumer's perception and experience of personal media.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.521-524
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• 2009

Everyone can easily acquire learning materials on web environment that rapidly develops. Because the importance of English education has been emphasized day by day, many English education systems are introduced. However, previous most English education systems support only single user mode, and cannot deal with a newly coined word such as 'WIKIPEDIA'. In order to lead a user's learning ability with interest and enjoyment, this paper propose an online English word game system implementing a 'scrabble' board game. The proposed English word game system has the following characteristics. First, the proposed system supports both single user mode and multi user mode with a virtual user based on artificial intelligence. Second, the proposed system can recognize newly coined words such as 'WIKIPEDIA' by using NEVER Open API dictionary. Third, the proposed system offers familiar user interface so that a user can play the game without any manual. Therefore, it is expected that the proposed system can help users to learn English words with interest and enjoyment.

• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.579-589
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• 2019

Due to the ban on the use of antibiotics, interest has been increasing for the development of therapeutic agents to treat various diseases using natural resources. Osthole, a natural coumarin compound used in traditional Chinese medicines, exerts an anti-inflammatory effect, but its effects in cows remain unknown. In this study, the effect of osthole on lipopolysaccharide (LPS)- or concanavalin-A (Con-A)- stimulated peripheral blood mononuclear cells (PBMCs) was assessed. Jugular venous blood was collected from Korean calves, and PBMCs were isolated. They were then used to study the immune response of PBMCs to treatment with osthole and LPS or Con-A for 72 h by measuring inflammatory cytokines including tumor necrosis factor-${\alpha}$ ($TNF-{\alpha}$) and interferon-${\gamma}$ ($IFN-{\gamma}$). Osthole significantly inhibited the mRNA secretion of $TNF-{\alpha}$ and $IFN-{\gamma}$ in a dose-dependent manner. Therefore, osthole inhibited LPS- or Con-A- induced $TNF-{\alpha}$ and Con-A-induced $IFN-{\gamma}$ production significantly in dose-dependent manner. These results clearly suggest that osthole inhibited the LPS- or Con-A- stimulated upregulation of pro-inflammatory cytokines in a dose-dependent manner, without causing obvious cytotoxic effects. Osthole could also protect cows from LPS- or Con-A- induced endotoxin shock, possibly by inhibiting the production of pro-inflammatory cytokines, which suggests that osthole might be a novel therapeutic agent for the prevention of inflammatory diseases.

• Korean Journal of Agricultural Science
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• v.48 no.3
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• pp.387-396
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• 2021

This study was conducted to provide basic data for efficient Hanwoo beef production by conducting a comparison of growth performance, blood metabolites, testosterone, and carcass characteristics of Hanwoo according to complete and hemi-castration. Twelve Hanwoo calves were allotted to two treatment groups as follows: CC = complete-castration and HC = hemi-castration method of removing only one testicle. At the end of the test, the body weight was 66 kg higher in HC than in CC, and the average daily gain increased by 12.6% (p < 0.05). The feed conversion ratio was significantly improved in HC compared to CC (p < 0.05). Serum cholesterol and triglyceride concentrations were significantly higher in CC than HC in both the growing and fattening periods (p < 0.05), and serum testosterone concentrations before castration were similar between HC and CC, but steadily increasing in HC after castration. Back fat thickness and marbling score were significantly higher in CC than HC in the entire period (p < 0.01). In the results of this study, hemi-castration can improve body weight gain and feed conversion ratio due to the influence of male hormones compared to complete castration, but it is considered that there will be difficulties in producing high-quality meat with a high marbling score.

• BMB Reports
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• v.54 no.8
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• pp.419-424
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• 2021

Cold-induced norepinephrine activates β3-adrenergic receptors (β3-AR) to stimulate the kinase cascade and cAMP-response element-binding protein, leading to the induction of thermogenic gene expression including uncoupling protein 1 (Ucp1). Here, we showed that stimulation of the β3-AR by its agonists isoproterenol and CL316,243 in adipocytes increased the expression of Ucp1 and Heme Oxygenase 1 (Hmox1), the principal Nrf2 target gene, suggesting the functional interaction of Nrf2 with β3-AR signaling. The activation of Nrf2 by tert-butylhydroquinone and reactive oxygen species (ROS) production by glucose oxidase induced both Ucp1 and Hmox1 expression. The increased expression of Ucp1 and Hmox1 was significantly reduced in the presence of a Nrf2 chemical inhibitor or in Nrf2-deleted (knockout) adipocytes. Furthermore, Nrf2 directly activated the Ucp1 promoter, and this required DNA regions located at -3.7 and -2.0 kb of the transcription start site. The CL316,243-induced Ucp1 expression in adipocytes and oxygen consumption in obese mice were partly compromised in the absence of Nrf2 expression. These data provide additional insight into the role of Nrf2 in β3-AR-mediated Ucp1 expression and energy expenditure, further highlighting the utility of Nrf2-mediated thermogenic stimulation as a therapeutic approach to diet-induced obesity.

• Korean Journal of Metals and Materials
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• v.49 no.3
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• pp.221-230
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• 2011

The cold spray process is an emerging technology that utilizes high velocity metallic particles for surface coating. Metallic powder particles are injected into a converging-diverging de Laval nozzle and accelerated to a high velocity by a supersonic gas flow. The cold spray process normally uses a circular nozzle that has a rather narrow spraying range. To overcome this fault, a slit nozzle was considered in this study. The slit nozzle is anticipated to reduce the coating process time because it has a wider coating width than the circular nozzle. However, the slit nozzle can reduce the coating efficiency because it does not allow as much gas and particle velocity as the circular nozzle. To improve the coating efficiency of a slit nozzle, the shape of the slit nozzle was modified. And the results of gas flow and particle behaviour according to the nozzlers shape were compared by the a numerical analysis. As a results, as Expansion Ratio(ER) of 7.5 was found to be the most optimal condition for enhancing the spraying efficiency when the ER was changed by the variation of nozzle neck and exit size.

• Journal of Animal Science and Technology
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• v.62 no.6
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• pp.893-902
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• 2020

This study was conducted to compare the mRNA expression levels of myogenic-adipogenic makers in the skeletal muscle and adipocytes formation, body weight, rumen weight, and papilla length on Hanwoo calves at newborn and 6 months of age. Animals used three newborn Hanwoo calves (NC) and three Hanwoo calves 6 months of age (SC). Body weight and rumen weight were significantly increased in SC compared to NC (p < 0.01), and papilla length was longer about 10-fold in SC than NC. Adipocytes was possible to visually identify more adipocytes in SC compared to NC, and were mainly formed around the blood vessels. mRNA expression of myogenin, myosin heavy chain 1 and myosin heavy chain 2A in both longissimus dorsi (LD) and semimembranosus (SM) was found to increase with calves growth (p < 0.01), and it was confirmed that have higher levels of mRNA expression in SM than LD. In LD tissues, the mRNA expression of stearoyl-CoA desaturase (SCD, p < 0.03) and peroxisome proliferator activated receptor γ (PPARγ, p < 0.04) was significantly higher in SC than NC. In SM tissues, mRNA expression levels of SCD (p < 0.02) and CCAAT/enhancer binding protein β (C/EBPβ, p < 0.01) were higher in SC than NC, and also mRNA expression levels of PPARγ increased, but there was no significant difference. Thus, the calves period suggests that it is an important step in the development of the rumen and the myogenesis and adipogenesis.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.6
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• pp.435-444
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• 2022

This study conducts capture simulations of space debris using a space-net. The present capture simulations are performed using ABAQUS, a nonlinear structural dynamics analysis code. A square space-net with 1 m × 1 m and a space debris with a cube configuration(0.3 m × 0.3 m × 0.3 m and 30 kg) are considered as baseline models. Using the baseline models, the capture simulation using ABAQUS is conducted to understand the capture process and establish the criteria of capture success or fail. In addition, the capture simulations are performed when various properties of the space-net are considered, and it is investigated that major design factors of the space-net are recognized to capture successfully the space debris.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.1
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• pp.17-34
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• 2023

This study aimed to develop a fitted torso pattern with an improved fit for inverted-triangular males in their twenties. For this study, six torso patterns were collected, compared and evaluated, and a fitted torso pattern was developed using virtual fittings. The research results are as follows. First, the fitted torso pattern received a good rating as a result of the virtual fitting evaluation: waist dart set 2 of the front; the amount of comfort is set at 5 cm around the chest, 4 cm around the waist and 10 cm around the hips. Second, the evaluation of virtual fitting of the development pattern showed that fit evaluation was 4.11/5 points, ease evaluation was 6.53/7 points, and that the stress map and airgap were suitable for the human body. Third, the actual fit evaluation of the development pattern was 4.25/5 points, 6.35/7 points for ease evaluation, and 4.81/5 points for motion evaluation. Fourth, there was no significant difference between the results of the virtual and actual fitting evaluation with the objectivity test. It is therefore possible to apply a pattern developed through a virtual fitting to an actual human body and to confirm the objectivity of the pattern.