• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.190-193
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• 2009

A recently reported simple phenomenological constitutive model (SK) demonstrated comparable or better data description capability to/than one of the rigorous and physics-based models, the PTW model. The simple SK model is believed to be an efficient model for practical applications where an extensive computation is needed, and can serve as a rigorous comparison standard for the development of a physics-based model.

• Journal of Applied Reliability
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• v.18 no.1
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• pp.33-39
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• 2018

Purpose: Accelerated degradation tests can be effective in assessing product reliability when degradation leading to failure can be observed. This article proposes an accelerated degradation test model for highly reliable solid state drives (SSDs). Methods: We suggest a nonlinear mixed-effects (NLME) model to degradation data for SSDs. A Monte Carlo simulation is used to estimate lifetime distribution in accelerated degradation testing data. This simulation is performed by generating random samples from the assumed NLME model. Conclusion: We apply the proposed method to degradation data collected from SSDs. The derived power model is shown to be much better at fitting the degradation data than other existing models. Finally, the Monte Carlo simulation based on the NLME model provides reasonable results in lifetime estimation.

• Proceedings of the Korean Society of Rheology Conference
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• 2001.09a
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• pp.163.4-163
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• 2001

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.76-80
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• 1998

In order to identify the cause of ground water drawdown of a piezometer installed around the LPG storage cavern, parameter estimations were conducted by inverse and forward numerical models. An inverse model, SK-EST developed by SK Engineering & Construction Co., Ltd.(SKEC,1997) was performed to estimate the change of the hydraulic conductivity. It was verified by the commercial forward model, AQUA3D (VATNASKIL,1995). The simulation results showed that the hydraulic diffusivity of the rock mass between the piezometer and the cavern had been increased and the change rate of the hydraulic head had been abruptly increased in response to the change of the operation pressure. Finally the statistical analysis for observed data showed the increase of the change rate of the hydraulic head and thus proved the applicability of SK-EST.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.69.4-69
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• 2002

1. Introduction 2. Fundamental Model 3. Simulation Procedure 4. Results 5. Conclusion

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.3
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• pp.161-167
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• 1997

A numerical model (SK-EST) for estimating hydraulic conductivity using monitoring data of underground LPG storage cavern was developed. The model calculates hydraulic conductivity from matrix equation which is established from the distribution of hydraulic potential. To verify the applicability of this model, an inverse analysis was performed using the monitoring data of pressure cell of an operating underground LPG storage cavern. And also using the water pressure parker test data which were obtained to look over the operation capability of pressure cell, conductivity variation with depth was estimated using the developed numerical model (SK-EST) and was compared with in situ results.

• The Korean Journal of Food And Nutrition
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• v.29 no.6
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• pp.923-929
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• 2016

The purpose of this study was to evaluate the protective effect of $PineXol^{(R)}$ on $H_2O_2$-induced cell death in SK-N-MC cells, and in early stage focal ischemia rodent model. SK-N-MC cells were pre-treated with $200{\mu}M$ $H_2O_2$ or various concentrations of $PineXol^{(R)}$ (10, 30, and 50 pg/mL) for 24 h, and then exposed to $H_2O_2$ for 3 h. Cell death was assessed by the CCK-8 assay, reactive oxygen species (ROS) assay, and lactate and dehydrogenase (LDH) release assay. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) expressions were also analyzed by western blotting. Focal ischemia rodent model was used as the in vivo model, and different concentrations of $PineXol^{(R)}$ (1, 10, and 100 mg/kg) were administered. One week after administration, reduction of infarct volume was analyzed by TTC staining. Cell viability of $H_2O_2$-treated SK-N-MC cells significantly increased by pre-treatment of $PineXol^{(R)}$ (p<0.05). $PineXol^{(R)}$ pre-treatment also induced significant decrease of ROS and LDH expressions. However, $PineXol^{(R)}$ did not affect the infarct volume. These results suggest that $PineXol^{(R)}$ has significant neuroprotective effect in vitro, but statistical significance was not confirmed in the in vivo focal ischemia model.

• Journal of Sensor Science and Technology
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• v.13 no.5
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• pp.342-349
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• 2004

SK (SPR Kinds) index, which can categorize the complicated measurement methods of surface plasmon resonance by simple method, has been proposed and verified. SK index is composed of three digits, where each digit presents the type of immobilized ligand, the type of illumination and the kinds of varying parameter, sequentially. The measurement method of (33#) series among SK indices shows the possibility of the multi-sensing capability, by which the response of 2-dimensional array of immobilized ligands can be detected simultaneously. The proposed possibility of multi-sensing capability has been verified by the modeling that is based on Fresnel reflection model.

• Asia Marketing Journal
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• v.15 no.4
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• pp.223-241
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• 2014

In May 2012, the collaboration of Hana Bank, top financial service company, and SK Planet, top telecommunication service provider, introduced a new credit card that was filled with all-in-one benefits into the market. Leveraging strong infrastructure of two companies, each top in its own industries, the awareness and preference of 'Club SK Card' brand rapidly increased to about 25% in less than one year. Moreover, this new card was enthroned in the most sold credit card of year 2012, accounting for a market share of 7.2% in the credit card market and more than 80% in the mobile credit card market. To make these results possible, 'Club SK Card' marketing team developed an effective marketing communication strategy which followed the 6M model. The mission of the marketing communication strategy was simple and clear. It was to deliver the card's inherent strengths on consumer benefits that come from the support of subsidiary and affiliated companies of SK Planet. According to OK Cashbag data, the marketing communication team selected the appropriate target consumers and approached them directly, inducing actual purchase behavior. The target consumers received straightforward messages about 'Club SK Card' and were led to join in the new membership at their most frequently visited supermarket or franchise restaurant. The straightforward communication message embedded in an eye-catching commercial ad with a hook song accompanied with a dance was delivered via public media. The ad became so popular that many other television programs quoted or made parodies of the ad. Courtesy of the commercial ad, the brand name disseminated rapidly and widely among the public. In October 2012, an ingenious planning and persistent implementation of the communication strategy results 'Club SK Card' to be ranked top in brand awareness as well as advertising preference tests.

• Asia Marketing Journal
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• v.8 no.3
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• pp.141-159
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• 2006

On November 16th 2004, SK Telecom Co., Ltd. launched 'MelOn' , an ubiquitous music service, into the first time in the world. It, new business model in Korea, was a great success in domestic music industry. Its key success factors are not only differential features of service but also the superiority of technical know-how, customer-oriented spirit, and marketing mix activities compared to many competitors. The case shows how MelOn developed and then introduces what on-line music service is identifying the key success factors and presenting visible outcomes. Furthermore discussing its business implications and future challenges.