• Korean Journal of Dental Materials
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• v.44 no.2
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• pp.171-178
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• 2017

The purpose of this study is to investigate the effect of number of times dipped in coloring liquid and sintering temperature on the flexural strength of zirconia ceramic. In this study, using a zirconia block having improved transparency, specimens with size of $25mm{\times}2mm{\times}1.5mm$ were fabricated. The zirconia ceramic specimens were divided into three groups according to the number of times dipped in coloring liquid by 0, 2 and 4 times, and dyed in the coloring liquid to give color to each specimen. Then, after sintering them at the final temperature of $1,450^{\circ}C$ and $1,600^{\circ}C$, flexural strength was measured using a universal testing machine (total 6 group, n=10 for each group). Also, a scanning electron microscopy (SEM) was performed to observe its microstructure, and the data obtained through the experiment were analyzed with two-way ANOVA. The results of the flexural strength analysis show that the highest value was measured $762.3{\pm}42.3MPa$ in EKL2 group, while the lowest value was $516.4{\pm}77.1MPa$ in EKH4 group. According to the results of the two-way ANOVAs, flexural strength was not related with interaction between sintering temperature and number of times dipped in coloring liquid ($R^2=0.737$). However, there were statistically significant differences in flexural strength depending on sintering temperature (P<0.001). The flexural strength of zirconia ceramics having improved transparency was dependent on sintering temperature. The number of times dipped in the coloring liquid did not affect flexural strength of the zirconia ceramic having improved transparency.

• The Journal of Korean Philosophical History
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• no.39
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• pp.29-52
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• 2013

Philosophy of respect righteousness advocated by Nammyung points to what first needs to be done to drive social changes. It is consistent with the Confucianism, which views the world from within oneself. After all, developing a proper view of the society starts from looking at oneself in the right perspective. The view that personal cultivation can develop into cultivation and eventually reform of the entire society is also present in Confucius' belief that one can only be at peace after disciplining oneself and observe good manners only after perseverance. Also, one can lead the world in peace only after disciplining one's body and mind. In other words, it suggests that individuals and the community where they belong to are not independent from one another. Rather, individuals gather to create a society and righteous individuals are the basis for righteous society. These principles of social system in Confucianism can be understood as a mutual or layered division and integration. The society is not conflicted with individuals or the nation but rather perceived as moral communities to co-exist. Hence, power of execution observed in the philosophy of respect and righteousness by Nammyung is identical to power of execution applied to the society. The power of execution shows up as 'the execution of righteousness' in Nammyung's philosophy of respect and righteousness. It is also demonstrated in the acts by Nammyung's disciples when the nation was at crisis. This is what differentiates Nammyung's new-Confucianism in Joseon Dynasty from Toegye or Yulgok as he tried to deliver 'the execution of righteousness.' It does not mean that neo-Confucian scholars did not emphasize the importance of execution, but Nammyung, in particular, warned how deceitful ideological or inner-directed thinking can be since they fail to come up with concrete solutions to social issues. In summary, Nammyung's moral discipline and training based on respect and righteousness cannot be evaluated in a state of vacuum separate from social and historical aspects but under the context of enlightening virtue and social execution. This can draw the conclusion that Nammyung's execution of respect and righteousness is in the starting point of the realistic 'theory of social reform' for creating a better world.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.22-29
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• 2011

The experiment investigated effect of duration, temperature, and light condition during chilling treatment on growth and flowering of four Campanula species in a factorial experiment. Two parent species, Campanula punctata Lam. var. rubriflora Mak. and C. Punctata Lam., and their two $F_1$ hybrids, C. punctata Lam. ${\times}$ C. punctata Lam. var. rubriflora Mak. ('Jiknyeo') and C. punctata Lam. var. rubriflora Mak. ${\times}$ C. punctata Lam. ('Gyeonu'), were used. Plants were cultured in vitro for five weeks at $25^{\circ}C$ under about $75{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD before being chilled at 4 or $25^{\circ}C$ for 3, 6, or 9 weeks under a darkened or lighted (about $10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD) condition. After chilling treatment, plants were transplanted to 10 cm pots filled with a commercial growing medium and were transferred to environment-controlled growth chambers and subsequently to a greenhouse to observe their reproductive growth. Growth of all species and flowering of a $F_1$ hybrid 'Jiknyeo' were affected by duration, temperature, and light condition during chilling treatment. The greatest growth and survival percentage were observed in C. punctata Lam. var. rubriflora Mak. The survival percentage was greater when plants were chilled in a lighted than darkened condition, whereas it decreased when plants were chilled more than six weeks in vitro. Among the four species tested, flowering was observed only in a $F_1$ hybrid 'Jiknyeo' with 62.5% flowering plants when it was chilled at $25^{\circ}C$ for three weeks under a lighted condition. Percent flowering plant was affected by duration, temperature, and light condition during chilling treatment. Three-week chilling at $4^{\circ}C$ under a darkened condition significantly reduced days to flowering. These results suggest that the low temperature requirement for flowering is not qualitative but quantitative in Campanula species. Further experiment with more number of plants is necessary to ascertain this conclusion.

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.65-73
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• 2010

To observe and analyze the characteristics of cloud and precipitation properties, the Cloud physics Observation System (CPOS) has been operated from December 2003 at Daegwallyeong ($37.4^{\circ}N$, $128.4^{\circ}E$, 842 m) in the Taebaek Mountains. The major instruments of CPOS are follows: Forward Scattering Spectrometer Probe (FSSP), Optical Particle Counter (OPC), Visibility Sensor (VS), PARSIVEL disdrometer, Microwave Radiometer (MWR), and Micro Rain Radar (MRR). The former four instruments (FSSP, OPC, visibility sensor, and PARSIVEL) are for the observation and analysis of characteristics of the ground cloud (fog) and precipitation, and the others are for the vertical cloud characteristics (http://weamod.metri.re.kr) in real time. For verification of CPOS products, the comparison between the instrumental products has been conducted: the qualitative size distributions of FSSP and OPC during the hygroscopic seeding experiments, the precipitable water vapors of MWR and radiosonde, and the rainfall rates of the PARSIVEL(or MRR) and rain gauge. Most of comparisons show a good agreement with the correlation coefficient more than 0.7. These reliable CPOS products will be useful for the cloud-related studies such as the cloud-aerosol indirect effect or cloud seeding. The visibility value is derived from the droplet size distribution of FSSP. The derived FSSP visibility shows the constant overestimation by 1.7 to 1.9 times compared with the values of two visibility sensors (SVS (Sentry Visibility Sensor) and PWD22 (Present Weather Detect 22)). We believe this bias is come from the limitation of the droplet size range ($2{\sim}47\;{\mu}m$) measured by FSSP. Further studies are needed after introducing new instruments with other ranges.

• Journal of Legislation Research
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• no.53
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• pp.525-551
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• 2017

This Article discusses the current trend of European competition damage actions focused on the recent Damage Directive and its transposition by the United Kingdom and Germany. The relevant Directive was signed into law in November 2014, and it requires the EU Member States to adopt certain measures to support competition damage actions. The required measures and principles by the Directive include right to full compensation, rebuttable presumption of harm, extensive disclosure of evidence, use of pass-on for defense and indirect purchaser suits. Although many Member States did not meet the deadline to transpose the Directive, the end of 2016, it is reported that 23 Member States have now, as of September 2017, made enactments according to the Directive. When we look at the transposition done by the United Kingdom and Germany, the revisions on their competition laws closely follow the contents of the Directive. However, it will take quite a long time before the amended provisions apply to actual cases since most of the new provisions apply to the infringement that take place after the date of the amendment. A similar situation regarding application time may happen in some other Member States. Furthermore, even if the terms of the competition laws of the Member States become similar following the Directive, the interpretations of the laws may differ by the courts of different countries. EU also does not have a tool to coordinate the litigations that are brought in different Member States under the same facts. It is true that the EU made a big step to enhance competition damage actions by enacting Damage Directive. However, it needs to take more time and resources to have settled system of competition private litigation throughout the Member States. Korea has also experienced increase in competition damage actions during the last fifteen years, and there have been some revisions of the relevant fair trade law as well as development of relevant legal principles by court decisions. Although there are some suggestions that Korea should have more enactments similar to the EU Directive, its seems wiser for Korea to take time to observe how EU countries actually operate competition damage actions after they transposed the Directive. Then, it will be able to gain some wisdom to adopt competition action measures that are suitable for Korean legal system and culture.

• Korean Journal of Social Welfare Studies
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• no.37
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• pp.319-344
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• 2008

The Purpose of this study is to observe the existence of welfare attitude split between welfare regimes clique and to explore the effect of institutional(regime) characteristics on welfare attitude. And Second purpose is to find the characteristics of structure of welfare attitude and then to clarify the characteristics of welfare attitude in Korea. This work contribute to find the point of solidarity and split and to work out the strategical clues for constructing pro-welfare politics. To compare the attitude on the state responsibility about the welfare, Sweden, France, US, and Korea is selected. And the effect of sex, age, education level, income class, and labor status which are abstracted from existing welfare state comparative study are analyzed. The result show the difference in welfare attitude score between countries. The welfare attitude score is Sweden, France and US in order. the Score in Korea is lowest. In the case of the effect structure of welfare attitude between countries, there are no differences between Sweden and France. But the specific characteristics in US and Korea, are observed. And the effect structure of sex, class, labor status is equal in Sweden, France, and US. That is, women, people in low class, and people in low labor status more emphasize the state responsibility on the welfare. But the effect structure of age of US is different comparing other countries. In US, the old age is tend to less support the state responsibility. The education level operate as the effect factor in only US. And Korea show the different effect structure on the welfare attitude. This understanding about structure of welfare consciousness become the basis to construct the strategy for welfare state by proposing the point of consensus and conflict to conversion of welfare paradigm.

• Journal of the Korean earth science society
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• v.40 no.5
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• pp.447-463
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• 2019

Sea surface wind is a fundamental element for understanding the oceanic phenomena and for analyzing changes of the Earth environment caused by global warming. Global research institutes have developed and operated scatterometers to accurately and continuously observe the sea surface wind, with the accuracy of approximately ${\pm}20^{\circ}$ for wind direction and ${\pm}2m\;s^{-1}$ for wind speed. Given that the spatial resolution of the scatterometer is 12.5-25.0 km, the applicability of the data to the coastal area is limited due to complicated coastal lines and many islands around the Korean Peninsula. In contrast, Synthetic Aperture Radar (SAR), one of microwave sensors, is an all-weather instrument, which enables us to retrieve sea surface wind with high resolution (<1 km) and compensate the sparse resolution of the scatterometer. In this study, we investigated the Geophysical Model Functions (GMF), which are the algorithms for retrieval of sea surface wind speed from the SAR data depending on each band such as C-, L-, or X-band radar. We reviewed in the simulation of the backscattering coefficients for relative wind direction, incidence angle, and wind speed by applying LMOD, CMOD, and XMOD model functions, and analyzed the characteristics of each GMF. We investigated previous studies about the validation of wind speed from the SAR data using these GMFs. The accuracy of sea surface wind from SAR data changed with respect to observation mode, GMF type, reference data for validation, preprocessing method, and the method for calculation of relative wind direction. It is expected that this study contributes to the potential users of SAR images who retrieve wind speeds from SAR data at the coastal region around the Korean Peninsula.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.4
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• pp.342-349
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• 2019

Purpose: The purpose of this study was to retrospectively investigate the survival and success rate of implant-supported fixed prosthesis according to the materials in the posterior area. Other purposes were to observe the complications and evaluate the factors affecting failure. Materials and methods: Patients who had been restored implant prosthesis in the posterior area by the same prosthodontist in the department of prosthodontics, dental hospital, Chonbuk National University, in the period from January 2011 to June 2018 were selected for the study. The patient's sex, age, material, location, type of prosthesis and complications were examined using medical records. The KaplanMeier method was used to analyze the survival and success rate. The Log-rank test was conducted to compare the differences between the groups. Cox proportional hazards model was used to assess the association between potential risk factors and success rate. Results: A total of 364 implants were observed in 245 patients, with an average follow-up of 17.1 months. A total of 5 implant prostheses failed and were removed, and the 3 and 5 year cumulative survival rate of all implant prostheses were 97.5 and 91.0, respectively. The 3 and 5 year cumulative success rate of all implant prostheses were 61.1% and 32.9%, respectively. Material, sex, age, location and type of prosthesis did not affect success rate (P>.05). Complications occurred in the order of proximal contact loss (53 cases), retention loss (17 cases), peri-implant mucositis (12 cases), infraocclusion (4 cases) and so on. Conclusion: Considering a high cumulative survival rate of implant-supported fixed prostheses, regardless of the materials, implant restored in posterior area can be considered as a reliable treatment to tooth replacement. However, regular inspections and, if necessary, repairs and adjustments are very important because of the frequent occurrence of complications.

• The Journal of Korean Obstetrics and Gynecology
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• v.27 no.1
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• pp.81-100
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• 2014

Objectives: The object of this study was to observe the in vitro anti-bacterial and anti-inflammatory effects of six single aqueous herbal extracts-Quisqualis Fructus (QuF), Meliae Cortex (MeC), Arecae Semen (ArS), Crassirhizomae Rhizoma (CrR), Ulmi Pasta Semen(UlS), Torreyae Semen(ToS)- against Staphylococcus aureus (S. aureus) and Lipopolysaccharide(LPS)-activated Raw 264.7 cells. Methods: Anti-bacterial activities against S. aureus of aqueous extracts of QuF, MeC, ArS, CrR, UlS and ToS were detected using standard agar microdilution methods. In addition, the effects on the cell viability, prostaglandin $E_2$ ($PGE_2$), nitric oxide (NO), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin (IL)-$1{\beta}$ and IL-6 productions of LPS activated Raw 264.7 cells were detected. The anti-bacterial and anti-inflammatory effects were respectively compared with lincomycin and piroxicam. Results: Minimal Inhibition Concentration (MIC) of aqueous extracts of QuF, MeC, ArS, CrR, UlS and ToS against S. aureus was respectively detected $5.625{\pm}4.075$ (3.125~12.500), $0.332{\pm}0.273$ (0.098~0.782), $1.094{\pm}0.428$ (0.782~1.563), $2.969{\pm}2.096$ (0.782~6.250), $9.375{\pm}4.419$ (3.125~12.500)>25 mg/ml. MIC of lincomycin was detected as $0.469{\pm}0.297$ (0.195~0.782) ${\mu}g/ml$ at same conditions. In addition, $ED_{50}$ against LPS-induced cell viabilities and cytokine releases of QuF, MeC, ArS, CrR, UlS and ToS was as follows - Cell viability: 66.370, 2.908, 1.747, 259.553, 18.150 and 34.160 mg/ml; NO production: 389.486, 0.294, 0.138, 523.060, 45.363 and 49.327 mg/ml; $PGE_2$ production: 114.271, 0.223, 0.046, 243.078, 8.829 and 28.947 mg/ml; TNF-${\alpha}$ production: 406.288, 0.343, 0.123, 9404.227, 125.406 and 140.775 mg/ml; IL-$1{\beta}$ production: 117.178, 0.135, 0.019, 237.451, 7.923 and 19.418 mg/ml; IL-6 production: 31.261, 0.105, 0.055, 128.434, 2.290 and 3.745 mg/ml. ED50 of piroxicam against LPS-induced cell viabilities, NO, $PGE_2$, TNF-${\alpha}$, IL-$1{\beta}$ and IL-6 were detected as 35.179, 6.552, 1.162, 7.273, 7.101 and $5.044{\mu}g/ml$, respectively at same conditions. Conclusions: All six single aqueous herbal extracts showed anti-bacterial effects against S. aureus, in the order of MeC, ArS, CrR, QuF and UlS aqueous extracts except for ToS; they did not showed any anti-bacterial effects (MIC>25 mg/ml). They also showed anti-inflammatory effects against LPS-activated Raw 264.7 cells in the order of ArS, MeC, UlS, ToS, QuF and CrR aqueous extracts. It means that the ArS and MeC will be showed favorable potent anti-bacterial and related anti-inflammatory effects.

• Korean Journal of Optics and Photonics
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• v.31 no.1
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• pp.1-6
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• 2020

The chest wall, an organ directly affected by environmental particles through respiration, consists of ribs, a pleural layer and intercostal muscles. To diagnose early and treat disease in this body part, it is important to visualize the details of the chest wall, but the structure of the pleural layer cannot be seen by chest computed tomography or ultrasound. On the other hand, optical coherence tomography (OCT), with a high spatial resolution, is suited to observe pleural-layer response to talc, one of the fine materials. However, intensity-based OCT is weak in providing information to distinguish the detailed structure of the chest wall, and cannot distinguish the reaction of the pleural layer from the change in the muscle by the talc. Polarization-sensitive OCT (PS-OCT) takes advantage of the fact that specific tissues like muscle, which have optical birefringence, change the backscattered light's polarization state. Moreover, the birefringence of muscle associated with the arrangement of myofilaments indicates the muscle's condition, by measuring retardation change. The PS-OCT image is interpreted from three major perspectives for talc-exposure chest-wall imaging: a thickened pleural layer, a separation between pleural layer and muscle, and a phase-retardation measurement around lesions. In this paper, a rabbit chest wall after talc pleurodesis is investigated by PS-OCT. The PS-OCT images visualize the pleural layer and muscle, respectively, and this system shows different birefringence of normal and damaged lesions. Also, an analyisis based on phase-retardation slope supports results from the PS-OCT image and histology.