• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.3
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• pp.188-196
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• 2009

Due to its high power density, long cycle life and clean nature supercapacitors are widely used for improving the dynamic characteristics of the new and renewable energy sources and extending the battery run-time and life. In this paper improved dynamic model of the supercapacitor is developed by the electrochemical impedance spectroscopy technique. The developed model can be used to accurately estimate the dynamic behaviour of the supercapacitor and calculate the exact capacitance value at a certain state of charges. The model of the supercapacitor in the frequency domain is equivalently transformed into that in the time domain for Matlab/Simulink simulaton. The simulation data shows fine agreements with experimental results, thereby proving the validity and the accuracy of the developed model.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.10
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• pp.1412-1416
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• 2014

We report thin-film organic moisture barriers based on polystyrene(PS) laminates deposition by PECVD for an encapsulation of OLEDs. The organic polystyrene thin-film has the benzene ring structure and high hydrophobic characteristics and it was polymerized by PECVD in dry process. Life time properties of Ca test were obtained 32 minutes at the RF 100W process conditions. From the AFM test, the roughness of multi-layer thin-film was more excellent rather than that of a single-layer thin-film. In addition, 5 layers of the multi-layer film properties were obtained 45 minutes. So that the optical and electrical properties were not affected with these plasma polymerized organic thin-film encapsulation. For life time improvement, the inorganic $Al_2O_3$ thin-film were deposited 5nm using ALD atomic layer deposition. The WVTR(Water Vaper Transmission Rate) value of hybrid thin-film encapsulation in the optimum process conditions was resulted by less than $10-3g/m^2/day$. From the results of experiment, plasma polymerized hybrid encapsulation was suggested as the flexible display applications.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.123-130
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• 2006

Recently, Korean government promotes BTL(Build-Transfer-Lease) for their public construction project to apply private sector's experience and finance initiatives. Many of public buildings and civil infrastructure projects were planned to be delivered by BTL and it helps to continue public projects under tight budget conditions. Since the characteristics of BTL projects, creative ideas for the project function, performance and its LCC (Life Cycle Cost) become more important than usual public work project. This paper introduces the systematic "VE job Plan" application techniques for BTL project and shows the process. This study shows the application of "VE job Plan" for BTL project to help decision making and value improvement. Also, Project cost was estimated by LCC (Life Cycle Cost) analysis. Technical "FAST diagram"was developed and used to find major functions of the project. So, it helps to improve performance of functions and make creative ideas. FAST diagram also help to find relationships between functions and cost. A case study (Daegu Art Gallery BTL Project) was conducted using proposed "VE job Plan. Study demonstrates how value management helps save money and increase functional performance. Researcher found that project can save cost and improve performance of functions significantly by using appropriate VE analysis process at appropriate time.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.223-228
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• 2010

This experiment was conducted to select optimal cultivars of long leaf vase life for flower arrangements among 21 Hosta cultivars that were selected based on their ornamental value. As a result of the investigation, the cultivar with the longest leaf vase life was 'June' with 29 days record. The cultivars with a more than 10 days record were 'Remember Me', H. lancifolia var. grandiflora, 'Grand Marquee', 'Dress Blue', 'Blue Dimples', 'Frosted Dimples', 'Birchwood Park's Gold', 'Krossa Regal', and 'Paradise Power'. These 10 cultivars had a high chlorophyll content, and had low chlorophyll content changes over time and were high in water absorption. The 10 selected cultivars had equal characteristics of increase in chlorophyll content within a certain period of time. These cultivars have a longer vase life when compared to others. This indicates the potential to develop better materials be use with flower arrangements.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.5
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• pp.933-940
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• 2024

In this study, an exponential family life distribution suitable for reliability analysis of system failures was applied to the NHPP-based software development model, and then the performance of models were newly evaluated by substituting the failure time data requested by the developer. First, as a result of analyzing the m(t) function that determines the model performance, all models showed the property of overestimating the ability to predict the true value. However, the Burr-Hatke-Exponential model, which showed the smallest error, was efficient. Second, the Lindley model was found to be the best when total evaluating the properties of the model performance (m(t), development cost, release time). Therefore, through this study, the performance of the exponential family life distribution was newly explored, and by utilizing related data, developers can identify required properties at an early stage and use them as basic reference data during the development testing phase.

• Journal of Life Science
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• v.18 no.6
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• pp.865-870
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• 2008

The purpose of this study was to examine resting metabolic rate (RMR) and thyroid hormonal (TSH, $T_3$, and $T_4$) changes following weight loss by diet with regular exercise in obese women. The subjects of the present study were 7 women who were above 30% body fat. The subjects arrived into the laboratory in the morning after 12 hour overnight fasting. All subjects measured RMR, % body fat, and fat free mass at weight loss program start time, after 4 weeks and after 8 weeks. All the RMR values were expressed as absolute value (kcal/day), absolute value/FFM (kcal/day/FFM), and absolute value/BSA (kcal/$m^2$/hr), and were calculated predicted RMR value minus actual RMR value. Also, correlation of blood thyroid hormonal (TSH, $T_3$, and $T_4$) secretion and RMR were analyzed. There were significant differences in weight, % body fat, and BSA following diet with exercise (p<0.05). Also, there was a difference between predicted RMR and actual RMR value following weight loss (p<0.05). We also examined the hormonal changes according to weight loss. After weight loss, the level of TSH and $T_4$ were higher than before. But there were no significant differences. Also, the level of $T_3$ was lower than rather before but there was no significant difference. Among the anthropometric factors, FFM was highly correlated (r=0.761) with actual RMR value before weight loss. Also, there was a correlation (r=0.771) with actual RMR value after weight loss. Therefore, actual RMR expressed as FFM increased in weight loss program by diet with exercise. There were no changes in the level of thyroid hormonal TSH and $T_4$.

• Asia Marketing Journal
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• v.16 no.1
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• pp.101-116
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• 2014

In the year 2013, Warren Buffett was named one of the most influential people of the year by TIME magazine. When people are exposed to such news, they show strong interest in who the influential people are and how those people became so successful. Likewise, people show strong attachment to other prominent figures as well. This social phenomenon indicates that people perceive well-known persona like business leaders, TV stars or sports stars etc. as human brands of intangible assets. As the role of these human brands is becoming more important, people tend to develop stronger attachment toward them. Another notable modern social phenomenon is people's pursuit of life-satisfaction and social well-being. People desire to increase their quality of life by having quality time with family and friends, and also by building attachment towards celebrities, sports stars, and so on. The main objective of this study is to examine how attachment toward human brands affects quality of life. While existing studies on human brands examined antecedents of attachment, e.g., some needs fulfillment such as A-R-C needs (autonomy, relatedness and competence needs) fulfillment, this study focuses on the outcome variables of attachment, e.g., how attachment toward human brands affects stress relief and life satisfaction through self-efficacy. Based on previous research, we divided human brands into two types: heroes and celebrities. Heroes are defined as people who have considerable and lasting importance on both societal and individual levels, and celebrities are defined as people who are well-known but have little or no short-term impact on society and individual levels. This study focuses on how attachment toward each type of human brands, celebrities and heroes, affects the quality of life or well-being. This study focuses on three important outcome variables; stress relief, life satisfaction, and self-efficacy, (three variables) which have been recently gaining importance, especially in the domain of positive psychology. Major findings from the present study show that although celebrities draw attachment from people by providing fun and entertainment or providing stress relief, they have weak influences on the wellbeing or efficacy of individuals at a deeper level. In contrast, attachment toward heroes helps people live better by providing meaning and positively influencing life satisfaction through self-efficacy (Frankl 1997). These results are consistent with the main tenet of 'positive psychology' which seeks "to find and nurture genius and talent and to make normal life more fulfilling" (Seligman and Csikszentmihalyi 2000). Considering the fact that certain celebrities are perceived as heroes to some, we can conclude that celebrities can become heroes if they provide meaning and value to the lives of people. This study contributes to the research stream of human brands since the most current leading research (e.g., Thomson 2006) indicated the need to look at the resulting effect of attachment on life satisfaction through self-efficacy. Another important contribution is that we empirically documented the different effects of celebrities and heroes. As expected, this study shows that heroes more deeply influence the lives of individuals in the long term while celebrities do so rather shallowly in the short term. The issues of the influence of heroes on the individuals' lives need to be further investigated in relation with the perspective of positive psychology.

• Tribology and Lubricants
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• v.37 no.1
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• pp.7-13
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• 2021

Ball bearing is a device that supports and transmits a load acting on a rotating shaft, and it is a type of rolling bearings that uses the rolling friction of the balls by inserting balls between the inner ring and the outer ring. Grease, which is prepared by mixing a thickener with a base oil, is a lubricant commonly used in bearings and has the advantage of a simple structure and easy handling. Bearings are increasingly being used in high value-added products such as semiconductors, aviation, and robots in the era of the 4th industrial revolution. Accordingly, there is an increasing demand for bearing grease. The selection of grease is an important factor in the bearing design. Therefore, a study must be conducted on the grease life evaluation to select an appropriate grease according to operating conditions such as a high temperature, high rotational speed, and high load. In this study, we evaluate the life of ball-bearing grease according to various operating conditions, namely, temperature, speed, and load changes. For this, we develop and theoretically verify a grease life test machine for ball bearings. We conduct a life test of grease according to various operating conditions of bearings and predict the grease life with a 10% and 50% failure probability using the Weibull analysis. In addition, we analyze the oxide characteristics of the grease over time using the Fourier transform infrared spectroscopy and the deterioration characteristics of the grease using the carbonyl index.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.14 no.2
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• pp.229-239
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• 1996

for shortening of running time on existing line, speed up railways feel strongly the necessity of it, for fully realizing a role of transportation system, for human life style is high. and increasing of time value. Especially curved lines zone have crucial effects on the speed of train, in case the shortening of running time, it is thought, speed up in curved lines zone, considering a character of route alignment in korea, we obtain saving time using lateral force index for safety running of train and comfortable ride of passengers. The results of this study show that all curved zone improvements for the shortening of the train running time more efficiently than extension of transition curve.

• Journal of the Korea Safety Management & Science
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• v.5 no.1
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• pp.83-92
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• 2003

Scheduling plays an important role in shop floor planning. A scheduling shows the planned time when processing of a specific job will start on each machine that the job requires. It also indicates when the job will be completed on every process. Thus, it is a timetable for both jobs and machines. There is only one server available and arriving work require services from this server. Job are processed by the machine one at a time. The most common objective is to sequence jobs on the severs so as to minimize the penalty for being late, commonly called tardiness penalty. Based on other objectives, many criteria may serve as s basis for developing job schedules. The process also comprises all strategic planning, capital investments, management decisions, and tasks necessary to create a new product. manufacturing processes must be created so that the product can be produced in the product facility. Purchasing new equipment and training workers may be required if new technology is to be used. Tools, fixtures, and the sequence of steps in the manufacturing processes must all be developed to allow rapid, high-quality, cost effective production. Also, it may be needed to be rearrange the production facility to adapt to the new manufacturing processes. Therefore, this study tries to proposed that Scheduling by customer needs group for minimizing the problem and reducing inventory, product development time, cycle time, and order lead time.