• The Journal of Advanced Prosthodontics
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• v.14 no.6
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• pp.335-345
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• 2022

PURPOSE. This in vitro study aimed to evaluate the surface characteristics of a full veneer crown fabricated chairside (CS) from a (Y, Nb)-TZP zirconia block in response to conventional zirconia grinding and polishing. MATERIALS AND METHODS. Zirconia crowns (n = 40) were first prepared and divided into two groups of materials: Labside (LS) and CS, after which each specimen went through a five-step grinding and polishing procedure. Following each surface treatment, surface characteristics were analyzed using confocal laser microscopy (CLSM), average surface roughness (Ra) values were processed from the profile data through Gaussian filtering, and X-ray diffraction pattern analysis was performed to evaluate the monoclinic (M) phase content. Then, a representative specimen was selected for field-emission scanning electron microscopy (FE-SEM), followed by a final analysis of the roughness and X-ray diffraction of the specimens using the independent t-test and repeated measures analysis of variance (RM-ANOVA). RESULTS. In every group, polishing significantly reduced the Ra values (P < .001). There was no significant difference in Ra between the polished state CS and LS. Furthermore, CLSM and FE-SEM investigations revealed that even though grain exposure was visible in CS specimens throughout the as-delivered and ground states, the exposure was reduced after polishing. Moreover, while no phase transformation was visible in the LS, phase transformation was visible in CS after every surface treatment, with the M phase content of the CS group showing a significant reduction after polishing (P < .001). CONCLUSION. Within the limits of this study, clinically acceptable level of surface finishing of (Y, Nb)-TZP can be achieved after conventional zirconia polishing sequence.

• Progress in Superconductivity and Cryogenics
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• v.16 no.2
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• pp.36-41
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• 2014

Temperature dependence of magnetic moment (m-T) and the magnetization (M-H) at 5 K and 20 K of the in situ processed $MgB_2$ bulk pellets with/without carbon (C) doping were examined. The superconducting critical temperature ($T_c$), the superconducting transition width (${\delta}T$) and the critical current density ($J_c$) were estimated for ten test samples taken from the $MgB_2$ bulk pellets. The reliable m-T characteristics associated with the uniform $MgB_2$ formation were obtained for both $MgB_2$ pellets. The $T_cs$ and ${\delta}Ts$ of all test samples of the undoped $MgB_2$ were the same each other as 37.5 K and 1.5 K, respectively. The $T_cs$ and ${\delta}Ts$ of the C-doped $MgB_2$ were 36.5 K and 2.5 K, respectively. Unlike the m-T characteristics, there existed the difference among the M-H curves of the test samples, which might be caused by the microstructure variation. In spite of the slight $T_c$ decrease, the C doping was effective in enhancing the $J_c$ at 5 K.

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.669-673
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• 1992

The stability constants, K for the complexation of alkali metal cations(Li^+, Na^+, K^+, Rb^+, and Cs^+) with both 4,5: 13,14-dibenzo-6,9,12-triaza-bicyclo [15,3,1] heneicosa-1 (21),7,19-trioxa-2,16-dione (DBPDA) and 6,9,12-trioxa-3,15,21-triaza bicyclo [15,3,1] heneicosa-1 (21),17,19-triene-2,16-dione (PDA) in N,N-Dimethylformamide (DMF) were determined conductomatically at various temperatures. At all the experiment temperatures, the K value sequences of the alkali metal ions with DBPDA and PDA are Cs^+ > K^+ > Rb^+ > Li^+ > Na^+ and Cs^+ > K^+ > Rb^+ > Li^+ > Na+, respectively. The K values for DBPDA are larger those of PDA for alkali metal ions. The widely recounted "hole-size-selectivity" principle is not applicable to these complexation systems. From the K values obtained at different temperatures, {\delta}H and T{\delta}S for these complexation reactions were determined. The enthalpy change plays principal important role in the complex formation by DBPDA. However, in the case of PDA, the entropy change also contributes to its complex formation.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.5
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• pp.582-590
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• 2004

The purpose of this study was to evaluate thermal properties of Taekwondo wears with three different materials. As a begging step, the questionnaire survey about the actual condition of Taekwondo wears was conducted. With the results of the questionnaire, cotton/nylon(70/30) blended fabric(CN) that was newly woven with sweat absorbent finishing and cotton/spandex(95/5) blended fabric with flexibility property were developed. The same designed 3 Taekwondo wears with 3 different materials which were two different materials(CN and CS) and a current material(cotton/PET, CP) were made. Four young males volunteered for this study, they kicked and punched as Taekwondo action for 20 minutes. Mean skin temperature was the highest in CS(33.1${\pm}$0.8$^{\circ}C$) and the lowest in CP(32.7${\pm}$0.6$^{\circ}C$). Increasing degree of rectal temperature didn't show any significant difference. Clothing microclimate temperature on the thigh was higher in CS(32.8${\pm}$17.4$^{\circ}C$) than in CN(29.4${\pm}$1.1$^{\circ}C$) and CP(29.4${\pm}$1.0$^{\circ}C$). Clothing microclimate temperature on the back and humidity on the thigh didn't show any significant differences. Clothing microclimate humidity on the back was higher in CP(65${\pm}$20%RH) than in CS(61${\pm}$17％RH). Heart rate, total body weight loss, and local sweating were not significantly different by materials. Most subject responded more hot in CN than in others, but there were no significant differences at the subjective sensation of thermal humidity. They answered more comfortable in CN than in others. Tectile sensations were the best in CN and the worst in CS. From those results, first of all, it is necessary to be weighted on Taekwondo wears made of CN in the aspects of the dignity of military arts uniform. Secondly, CS was required to be lighted and enhanced for the subjective sensation. Third, CP weaved honey comb was asked more various design to eliminate sweat high competition power within the scope of the dignity of military arts uniform.

• Proceedings of the Korea Contents Association Conference
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• 2019.05a
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• pp.431-432
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• 2019

현재 전 세계 인구 76억명 중 스마트폰 사용자는 70%이상으로 스마트폰이 대중화가 되어 집이든 밖이든 누구나 자유롭게 이용하고 있다. 이에 본 논문에서는 HTML5와 CSS3를 기반으로 4차 산업혁명 대표 기술 중 하나인 IoT기술로 만든 제품을 주문받고 설치해주는 반응형 서비스판매 웹을 구성하고자 한다. 기존 웹과의 차별성과 고객 개개인의 만족도를 위해 제품판매 뿐만 아니라 주문제작 가능도 구현하여 고객의 욕구를 충족시키고자 한다.

• Journal of Ginseng Research
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• v.33 no.1
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• pp.13-25
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• 2009

Geochemical relationships between ginsengs and soils from three representative soil types, shale, phyllite and granite regions, from Keumsan were examined. High elements ere shown at the granite and shale areas of the weathered soils, the phyllite areas of he cultivated soils and the shale areas of the host rocks. T1 was enriched in ginsengs grown in the shale areas, Cs and B in the phyllite areas, and Be and Cd in the granite areas. Positive correlations were dominated by the shale areas. These relationships can be explained for mineral characteristics within the soils, and their behaviors related to the physio-chemical conditions. High elements were shown in the 2 year ginsengs of the hale areas, and 4 year ginsengs of the phyllite and granite areas in comparisons with ginsengs of the different ages from the same areas. These differences can be explained with ages of the ginsengs, solubilities of the minerals and physio-chemical differences within soils. The content differences of high elements such as Cs, T1 and Be were found between soils and ginsengs. Overall, these results suggest that components of ginsengs grown in the granite areas are chemically similar to the soils.

• Journal of Life Science
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• v.12 no.1
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• pp.22-26
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• 2002

CS21 lymphoma cells that preferentially metastasize to lymph nodes after s.c. inoculation into BALB/c mice were grown in vitro in the presence of CA12 stromal cells isolated from lymph nodes. To obtain fundamental data on identification and characterization of the soluble factor(s) produced by CA12 stromal cells, we investigated the biological profile of the conditioned medium produced by CAl2 stromal cells. CAl2 conditioned medium has no affinity with Con A. CAl2 conditioned medium is associated with the proliferation of splenic T- and thymic T-cells with-out adding mitogen, although the conditioned medium cannot induce the differentiation of thymocytes. Additionally, we showed that H-7, not HA-1004 inhibits CS21 cell proliferation. These results suggest that CAl2 conditioned medium has a specific soluble factor(s) produced by lymph node stromal cells.

• International Journal of Computer Science & Network Security
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• v.22 no.9
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• pp.1-6
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• 2022

Teaching and learning are one of the major issues during this pandemic (COVID-19). Since the pandemic started, there are many changes in teaching and learning styles as everything related to studies started online. Game-Based Learning has got remarkable importance in the educational system and pedagogy as an effective way of increasing student inspiration and engagement. In this field, most of the work has been carried out in digital games. This research uses an Animated Game-Based Learning design in enhancing student engagement and perception of learning. In teaching Computer Science (CS) concepts in higher education, to enhance the pedagogy activities in CS concepts, more specifically the concepts of "Data Structures (DS)" i.e., Array, Stack, and Queue concepts are focused. This study aims to observe the difference in students' learning with the use of different learning methods i.e., the traditional learning (TL) method and the Animated Game-Based Learning (AGBL) Method. The experimental results show that learning DS concepts has been improved by the AGBL method as compared to the TL method.

• Progress in Superconductivity and Cryogenics
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• v.16 no.1
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• pp.9-13
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• 2014

Effects of neutron irradiation on the superconducting properties of the undoped $MgB_2$ and the carbon(C)-doped $MgB_2$ bulk superconductors, prepared by an in situ reaction process using Mg and B powder, were investigated. The prepared $MgB_2$ samples were neutron-irradiated at the neutron fluence of $10^{16}-10^{18}n/cm^2$ in a Hanaro nuclear reactor of KAERI involving both fast and thermal neutron. The magnetic moment-temperature (M-T) and magnetization-magnetic field (M-H) curves before/after irradiation were obtained using magnetic property measurement system (MPMS). The superconducting critical temperature ($T_c$) and transition width were estimated from the M-T curves and critical current density ($J_c$) was estimated from the M-H curves using a Bean's critical model. The $T_cs$ of the undoped $MgB_2$ and C-doped $MgB_2$ before irradiation were 36.9-37.0 K and 36.6-36.8 K, respectively. The $T_cs$ decreased to 33.2 K and 31.6 K, respectively after irradiation at neutron fluence of $7.16{\times}10^{17}n/cm^2$, and decreased to 22.6 K and 24.0 K, respectively, at $3.13{\times}10^{18}n/cm^2$. The $J_c$ cross-over was observed at the high magnetic field of 5.2 T for the undoped $MgB_2$ irradiated at $7.16{\times}10^{17}n/cm^2$. The $T_c$ and $J_c$ variation after the neutron irradiation at various neutron fluences were explained in terms of the defect formation in the superconducting matrix by neutron irradiation.

• The Korean Journal of Pharmacology
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• v.25 no.1
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• pp.13-21
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• 1989

The circadian rhythm of spontaneous motor activity was not significantly altered by $T_4$(4mg/kg, i.p. inj. once a day for 5 days: $T_4$) and PTU (fed ad lib in 0.01% drinking water for 5 weeks: PTU). The plasma thyroxine level was markedly increased by $T_4$ but reduced by PTU, and the plasma thyrotropin level was markedly increased by PTU but moderately increased by $T_4$. Clonidine slightly increased the plasma CS level, but the clonidine effect was significantly enhanced by $T_4-pretreatment$. The brain NE and MHPG contents were little affected by $T_4$ but the NE content was significantly decreased by PTU. The SS-induced increase of plasma CS level was moderately decreased by PTU but increased by $T_4$. However, clonidine significantly inhibited the SS-induced increase, and the inhibitory effect of clonidine was not significantly affected by PTU and $T_4$, respectively. The brain MHPG content and MHPG/NE ratio were significantly decreased by clonidine but increased by SS. The clonidine- and SS-induced changes of brain MHPG content and MHPG/NE ratio were not altered by $T_4$. PTU did not affect the SS-induced increase of brain NE turnover but significantly attenuated the clonidine-induced decrease. The SS-induced increases of brain MHPG content and MHPG/NE rtatio were markedly inhibited by clonidine, and the inhibitory effect of clonidine was not affected by $T_4$ and PTU, respectively. These results suggest that the responses to swim-stress is not signigicantly affected by the alteration of thyroid function and that the hypothalamo-adenohypophysis-adrenocortical stimulation in response to swim-stress seems to be mediated via hypothalamic noradrenergic activation, and the stress response may be inhibited by the agonistic activity of clonidine on the presynaptic ${\alpha}_2-adrenoceptor$.