• Korean Journal of Materials Research
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• v.19 no.1
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• pp.7-12
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• 2009

TFT-LCD is the most popular type of flat display panel in the information technology field. The back light unit is a main part of the structure of a TFT-LCD panel. Occasionally, studies have shown that failures of the CCFL of the BLU occur due to the poor weld characteristics of these materials. The aim of this study was to prepare some technical data and to characterize a microjoined electrode for the CCFL. Microstructure examinations, microhardness measurements, resistance measurements and microtensile tests of the microjoined electrode were carried out. The result indicates that a large amount of grain coarsening exists in the heat-affected zone (HAZ) of the weld between the cup and the pin. This grain coarsening of the HAZ between the cup and pin is caused by the welding cycle, which may have an influence on the lowest microhardness values. Fracturing of the microjoined electrode also occurred at the HAZ close to the cup between the weld holding the cup and the pin. Additionally, no specific changes of the electrical resistance among the cup, pin, and lead wire themselves or in the microjoined electrode were observed.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.5
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• pp.75-89
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• 2019

In the present work, structural analyses for light weight corrugate 3 layered sandwich panels are carried out. The mechanical properties of the sandwich panels are obtained using the modified analytical closed form based on a corrugated panel deformation and the homogenization scheme of an uniaxial composite. Subsequently, the mechanical properties estimated by the two aforementioned methods were employed for the numerical analyses for the corrugated sandwich panels under the specifically loading conditions, and a comparison between two methods was also made.

• Journal of Labour Economics
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• v.43 no.4
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• pp.179-203
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• 2020

This study aims to compare and analyze the impact of labor unions on job training programs using two different longitudinal data, Workplace Panel Survey (WPS) and Korean Labor and Inocme Panel Study (KLIPS). By applying the Correlated Random Effect (CRE) model to both individual-level and establishment-level data, we observe that labor unions increase the likelihood that establishments provide employees with job training programs and workers participate in the trainings. Our results shed light on the role of labor unions to increase the opportunities of job training programs for workers.

• Acta Via Serica
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• v.6 no.2
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• pp.61-90
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• 2021

Recent excavations in Qinghai Province, China, have disclosed textiles and artworks from Tuyuhun-Tubo (Tibetan) tombs, dated to the 7^th-9^th centuries, that suggest artistic and cultural exchanges along an external southern branch of the main Silk Road, between Gansu and Sichuan Provinces, across the Qinghai-Tibetan plateau toward the Himalayas. Many similar textiles, possibly from this area, have appeared lately on the art market and ended in private collections. Although these textiles, dated to the early Tibetan period, follow a popular prototype established in Central Asia in the 6^th century, the technical features, colors, and other indigenous elements suggest that they were woven in workshops different from those established between Sogdiana and Gansu. The exhibition "Cultural Exchange Along the Silk Road - Masterpieces of the Tubo Period," organized by the Dunhuang Research Academy and the Pritzker Collaborative Art between July and October 2019 in Dunhuang, Gansu, was a groundbreaking event that gathered scholarly attention on early Tibetan material culture, but a relevant publication is still forthcoming. In my previous work, I briefly discussed a group of silk textiles, possibly from Qinghai or Sichuan, that I analyzed in 2014 in the China National Silk Museum in Hangzhou, Zhejiang. In light of the recent material excavated, published online, or displayed in Dunhuang, in this article, I reevaluate the data previously collected, and discuss in detail the technical and iconographic features of one of the fragments held in Hangzhou. Eventually, the piece was recognized as the ending part of a large panel, which is now in the Abegg Stiftung in Riggisberg, Switzerland.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_2
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• pp.1029-1036
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• 2022

The traditional outdoor advertising market has been stagnant recently, but the digital advertising market has been steadily increasing, and the digital signage market has been expanding despite the recent corona pandemic. However, in terms of hardware, new displays are required due to excessive power consumption, lack of visibility in sunlight, and continuous operating expenses. Since the e-paper display does not require a light emitting device therein, it is advantageous to solve above problems. In addition, it has the advantage of consuming power only when converting an image due to bistability, so it is suitable as hardware that implements images rather than moving pictures. Currently, one of the most successful examples of commercializing e-paper displays is ESL devices. According to a recent market study, the market for large-sized panels larger than 10 inches has grown at an annual rate of 21.6%, and the market is expected to exceed 30% by 2026. It is judged that it will be relatively easy to apply the roll-to-roll technology, which is currently developing the technology applied to OLED, to the e-paper display. Therefore, mass production technology and market expansion for ESL panel enlargement are expected, and a new market is also expected to be formed at the same time. New markets will be traffic signs, public displays, billboards, façades, kiosks, digital signage, and so on.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.3
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• pp.33-42
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• 2022

Oil prices have become more volatile as a result of global economic contraction and control measures. Before and during the COVID-19 crisis, this study examines the relationship between oil price swings and daily stock returns in the power sector. The impact is investigated using a panel Vector Autoregressive (VAR) model. Granger causality tests are used to see if oil prices are effective in predicting returns. The dynamic impact of supply shocks is studied using Impulse Response Functions (IRFs). From January 2011 to May 2021, the study used daily data from all listed power sector enterprises on the Pakistan stock exchange. To investigate the differences in reactions between the Pre-COVID and COVID eras, the sample was separated into two groups. Oil shocks are inversely associated with daily firm stock returns. The conclusions are further supported by the lack of impact of stock prices on oil prices. The relationship, however, deteriorates during the COVID pandemic. We could not uncover any evidence of a significant relationship. In developing countries that rely on oil imports, the study sheds light on the utility of oil price shocks in daily stock return predictions.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.12
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• pp.1931-1936
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• 2010

In Korean tilting trains, honeycomb composite panels are used for high speed and light weight. The side wall of a tilting train consists of an aluminum honeycomb coated with carbon-fiber-reinforced epoxy skin and a nomex honeycomb panel as the main structure, with glass wool inserted between the panels. In this study, based on ASTM E2249-02, we measure the intensity sound transmission loss (TL) of the honeycomb composite panels. Using mass law deviation (MLD), we estimate the sound insulation performance of the honeycomb composite panels in terms of their weight and explore the feasibility of substituting a conventional corrugated steel panel. The transmission-loss data of the honeycomb composite panels obtained in the study will be used to establish noise-reduction measures for train compartments.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.647-650
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• 2006

Low temperature polycrystalline silicon (LTPS) technology using a high power laser have been widely applied to thin film transistors (TFTs) for liquid crystal, organic light emitting diode (OLED) display, driver circuit for system on glass (SOG) and static random access memory (SRAM). Recently, the semiconductor industry is continuing its quest to create even more powerful CPU and memory chips. This requires increasing of individual device speed through the continual reduction of the minimum size of device features and increasing of device density on the chip. Moreover, the flat panel display industry also need to be brighter, with richer more vivid color, wider viewing angle, have faster video capability and be more durable at lower cost. Kornic Systems Co., Ltd. developed the $KORONA^{TM}$ LTP/GLTP series - an innovative production tool for fabricating flat panel displays and semiconductor devices - to meet these growing market demands and advance the volume production capabilities of flat panel displays and semiconductor industry. The $KORONA^{TM}\;LTP/GLTP$ series using DPSS laser and XeCl excimer laser is designed for the new generation of the wafer & FPD glass annealing processing equipment combining advanced low temperature poly-silicon (LTPS) crystallization technology and object-oriented software architecture with a semistandard graphical user interface (GUI). These leading edge systems show the superior annealing ability to the conventional other method. The $KORONA^{TM}\;LTP/GLTP$ series provides technical and economical benefits of advanced annealing solution to semiconductor and FPD production performance with an exceptional level of productivity. High throughput, low cost of ownership and optimized system efficiency brings the highest yield and lowest cost per wafer/glass on the annealing market.

• Journal of Korean Association for Spatial Structures
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• v.10 no.2
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• pp.117-126
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• 2010

Experiment on flexural analysis of RC beams strengthened with composite material panel is presented. Recently, the strengthening of reinforced concrete structures using advanced fiber reinforced plastic (FRP) composites, and in particular the behavior of FRP-reinforced concrete structure is topic that has become very popular because of good corrosion resistance and easy for site handling due to their light weight. In this study, an efficient computational analysis using ABAQUS to predict the ultimate moment capacity of reinforced concrete beams strengthened with FRP is presented. Test parameters in this study are the shape of fiber arrangement (LT, DB, DBT) and the number of carbon fiber sheets (2ply, 3ply). When comparing with results of the analytical model, results of the experiments show similar values. Furthermore, reinforced concrete beam with FRP obtains improved effects for ultimate strength.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.5
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• pp.171-176
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• 2001

Plasma Display Panel(PDP) is a type of flat panel display utilizing the light emission produced by gas discharge. Barrier Ribs of PDP separating each sub-pixel prevents optical and electrical crosstalks from adjacent sub-pixels. Mold for forming barrier ribs has been newly researched to overcome the disadvantages of conventional manufacturing process such as screen printing, sand-blasting and photosensitive glass methods. Mold for PDP barrier ribs have stripes of micro grooves transferring glass-material wall. In this paper, Stripes of grooves of which width 48${\mu}{\textrm}{m}$ and 270${\mu}{\textrm}{m}$, depth 124${\mu}{\textrm}{m}$, pitch 274${\mu}{\textrm}{m}$ was acquired by machining hard and brittle materials of WC, Silicon, Alumina with dicing saw blade. Maximum roughness of the bottom and sidewall of the grooves was respectively 120nm, 287nm in grooving WC. Maximum tilt angle caused by difference between upper-most width and lower-most width was 2$^{\circ}$. Maximum Radius of bottom curvatures was 7.75${\mu}{\textrm}{m}$. This results satisfies the specification for barrier ribs of 50 inch XGA PDP if the groove form of mold was fully transferred to the barrier ribs. Barrier ribs were formed with Silicone rubber mold, which is transferred from grooved hard materials. Silicone rubber mold has elasticity accommodating the waveness of lower glass plate of PDP.