• Journal of Applied Reliability
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• v.16 no.4
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• pp.356-363
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• 2016

Purpose: The purpose of this study is to propose efficiency of equipment testing the luminance degradation of OLED. Methods: The degradation model of Exponential model and Stretched exponential model is analyzed by goodness of fit test using calculated R-square. The degradation model having the higher R-square is finally selected. Scale parameter and Shape parameter using the selected degradation model is estimated. The activation energy and current density n using peck model among the accelerated model is estimated. the estimated parameters are analyzed by t-test. Results: The results of t-test show that the estimated parameters on chamber and hotplate are equal statistically. we can know the similarity of the luminance degradation rate and degradation pattern on chamber and hotplate. Conclusion: The result of the degradation test on chamber and hotplate is similar. when the accelerated degradation test on the panel of the OLED TV is performed, hotplate is requiring less samples, time and cost than chamber. so the accelerated degradation test on the panel of the OLED TV using the hoplate is efficient of time and cost.

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.3
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• pp.18-23
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• 2006

The formation degree of sustain (ITO pattern) determines the quality of a PDP (Plasma Display Panel). Thus, in the present study, we attempt to detect 100% of the defects that are larger than $30{\mu}m$. Currently, the inspection method in the PDP manufacturing process is dependent upon the naked eye or a microscope in off-line mode. In this study, a prototype inspection system for PDP ITO patterned glass is developed. The developed system, which is based on a line-scan mechanism, obtains information on the defects and sorts the defects by type automatically. The developed inspection system adopts a multi-vision method using slit-beam formation for minimum inspection time and the detection algorithm is embodied in the detection ability. Characteristic defects such as pin holes, substances, and protrusions are extracted using the blob analysis method. Defects such as open, short, spots and others are distinguished by the line type inspection algorithm. It was experimentally verified that the developed inspection system can detect defects with reliability of up to 95% in about 60 seconds for the 42-inch PDP panel.

• Advances in concrete construction
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• v.9 no.5
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• pp.437-448
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• 2020

In high rise buildings that utilize precast large panel system for construction, the shear wall provides strength and stiffness during earthquakes. The performance of a wall panel system depends mainly on the type of connection used to transfer the forces from one wall element to another wall element. This paper presents an experimental investigation on different types of construction detailing of the precast wall to wall vertical connections under reverse cyclic loading. One of the commonly used connections in India to connect wall to wall panel is the loop bar connection. Hence for this study, three types of wet connections and one type of dry connection namely: Staggered loop bar connection, Equally spaced loop bar connection, U-Hook connection, and Channel connection respectively were used to connect the precast walls. One third scale model of the wall was used for this study. The main objective of the experimental work is to evaluate the performance of the wall to wall connections in terms of hysteretic behaviour, ultimate load carrying capacity, energy dissipation capacity, stiffness degradation, ductility, viscous damping ratio, and crack pattern. All the connections exhibited similar load carrying capacity. The U-Hook connection exhibited higher ductility and energy dissipation when compared to the other three connections.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.844-847
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• 2003

Display devices are becoming increasingly important as an interface between humans and machines in the growing information society. In display devices, PDP (Plasma Display Panel) has many advantages in that it has wide screen, wide viewing angle and is light weight, thin. In PDP driving method, if the brightness of input image is high, applying the fixed sustain pulse to the PDP panel will raise the PDP power consumption and may damages the PDP panel. To overcome these problems, the Plasma AI driving method was introduced by the Matshushita co. in Japan. The Plasma AI driving module calculates the peak value and average value of 1 frame image and adjusts the gradation and sustain pulses for 1 frame sustain. In this paper, the proposed PDP driving module is based on the Plasma AI driving module. The proposed driving module calculates peak value and average value, and the brightness distribution of 1 frame image. Using brightness distribution, the proposed driving module divides 1 frame input image into 15 image patterns. For each image pattern, minimum sustain pulses and sub-frames are used for the brightness of 1 frame image and the sustain weight for 64, 128, 192 gradation is proposed. Therefore, the sustain power consumption can be reduced.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.4
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• pp.1-10
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• 2000

A panel method based on the raised panel approach is developed for the nonlinear ship wave problem of practical hull forms. For the validation of the present numerical scheme. the developed method is first applied to Series 60 hull for which the extensive experimental data are available. As practical applications. the developed method is applied to KRISO 3600 TEU container ship and KRISO 300K VLCC. With the primary emphasis on the nonlinear effects of the global wave pattern generated by the two commercial ships. the calculated wave patterns are compared and verified with the experiments of KRISO. It is found that the calculated results of the present method are quite satisfactory compared with the linear methods like Dawson's approach and Neumann-Kelvin solution.

• Human Ecology Research
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• v.53 no.5
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• pp.489-502
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• 2015

This study identifies the relation between recognition relatively deprivation and consumption patterns. The data used were the seventh Korea Welfare Panel Study (KOWEPS). The final sample of 1,597 households was selected based on several sampling steps standard weights suggested by KOWEPS were applied. The final sample was subdivided into household recognizing relatively deprivation (51.7%) and non-household recognizing relatively deprivation (48.3%) per level of subjective income and objective income. We derived six consumption patterns from the cluster analysis as per consumption ratio: transportation dominant consumption pattern, essential consumption pattern, other dominant consumption pattern, care attention consumption pattern, private transfer consumption pattern, and education dominant consumption pattern. The results of this study are as follows. The analysis of the determinants of recognizing relatively deprivation in regards to question one found that the household was likely to be relatively deprived when: the head of a household was older, a household had a dual income, children and more total assets then those assessed 1 year ago compared to household living conditions, result of comparing the consumption patterns difference between household recognizing relatively deprivation and non-household recognizing relatively deprivation indicated that household recognizing relatively deprivation was more likely to belong to the transportation dominant consumption pattern, other dominant consumption pattern, and private transfer consumption pattern. The multinomial logistic analysis conducted to understand the determinants affecting the consumption patterns of household recognizing relatively deprivation indicated differences in demographic characteristics, household-related variables, financial variables and perception of economic conditions.

• Journal of the Korean Statistical Society
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• v.29 no.1
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• pp.29-44
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• 2000

In this paper, we consider one-level rotation designs with finite rotation groups such that the design satisfies two basic requirements: all rotation groups are included in any given survey period, and overlapping rates depend only on the time lag. First we present the necessary number of rotation groups and a rule for the length of time the sample units are to be in or out of the sample to satisfy the requirements. Second, an algorithm is presented to put rotation groups to proper positions in a panel in order to include all finite rotation groups for any survey period. Third, we define an one-level rotation pattern which is invariant in the survey period and has useful properties in practical sense.

• The Journal of Information Systems
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• v.22 no.1
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• pp.165-180
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• 2013

Using long-term panel data of OKCashbag, this study analyzes whether learning effect influencing in effectiveness of coalition loyalty program exists. We found that there is learning effect in the behavior of loyalty program customers, and discovered that learning effect appears more greatly in using (redeeming) behavior than accumulating behavior. The authors also found a long-lasting structural changes in the pattern of point redemption after a major marketing activities associated with the act of using points. The results of this research can contribute to suggest direction to the future researches to examine differences of learning effect according to demographic (gender, age, region, ect.) and transactional (frequency or scale in point accumulation and redemption etc.) characteristics.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.9
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• pp.7-11
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• 2007

The objective of this study is to evaluate the characteristics of a newly proposed high-speed drive method for the gray scale display for high-resolution plasma display panels(PDP). In the experiment it was found that the characteristics of gray scale display are not closely affected by a priming period below 50[${\mu}s$], the width of the priming period, and that it can be driven stably from the brightest sub-field to the darkest sub-field even though a priming discharge is applied to the 1 TV-field only once. Moreover, from the experimental result, the gray scale pattern of 8-bit and 9 sub-fields was stably displayed in the experimental PDP with scan pulses having the pulse width of 0.7[${\mu}s$]. An address voltage margin of about 25[V] and a sustain voltage margin of about 10[V] was obtained.

• Journal of the Korea Institute of Building Construction
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• v.8 no.3
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• pp.69-74
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• 2008

TProduction's adaptation manufactured construction component is enlarged the result of development in the various construction products and technology. But the pre-fabricated unit bathrooms are not used in spite of many advantages which occupies less than 10% of its market share. This study is for the alternative methods through the on-the-spot experiments to lessen resonance of the wall panel in the Unit bathroom. The results are summarized as follows. Unit bathroom was effective in suitableness part noise control performance when attach sound-absorbing materials. But noises control performance was not better than the general used bathroom. When Urethane (egg container pattern) was applied in the unit bathroom, unit bathroom can be expected for utilization in the construction market field.