• Animal Systematics, Evolution and Diversity
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• v.21 no.2
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• pp.259-272
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• 2005

The antipatharians in Korea were known with three species and two genera belonging to family Antipathidae. In the present study, three species, Antipathes densa, A. grandiflora, and A. dubia, have been newly recorded to Korean antipatharian fauna with the samples collected from Jeju-do during the period from 2003 to 2005. The description was mainly based on the habitat, the branching mode of corallums, the size and arrangement of polyps and spines on the axis, and also the types of cnidae. They had three kinds of cnidae: spirocyst, basitrich, and microbasic p-mastigophore. Spirocysts and basitrichs were distributed at tentacles and microbasic p-mastigophores were mainly at septal filaments.

• Smart Structures and Systems
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• v.13 no.6
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• pp.943-957
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• 2014

When subjected to fatigue loading, the main failure mode of partially prestressed concrete (PPC) structure is the fatigue fracture of tensile reinforcement. Therefore, monitoring and evaluation of the steel stresses/strains in the structure are essential issues for structural design and healthy assessment. The current study experimentally investigates the possibility of using fiber Bragg grating (FBG) sensors to measure the steel strains in PPC beams in the process of fatigue loading. Six full-scale post-tensioned PPC beams were exposed to fatigue loading. Within the beams, the FBG and resistance strain gauge (RSG) sensors were independently bonded onto the surface of tensile reinforcements. A good agreement was found between the recorded results from the two different sensors. Moreover, FBG sensors show relatively good resistance to fatigue loading compared with RSG sensors, indicating that FBG sensors possess the capability for long-term health monitoring of the tensile reinforcement in PPC structures. Apart from the above findings, it can also be found that during the fatigue loading, there is stress redistribution between prestressed and non-prestressed reinforcements, and the residual strain emerges in the non-prestressed reinforcement. This phenomenon can bring about an increase of the steel stress in the non-prestressed reinforcement.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1132-1143
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• 2008

A single Column/Shaft which extended the pile to the column of the bridge with same diameter has better safety and economical profit, but it usually has larger lateral displacement due to lateral loads such as wind, earthquake, wave, etc. A series of horizontal pile load testing were performed to study the lateral behavior of single column/shaft with varying different free lengths and embedded pile lengths. Eight instrumented test piles were cast-in-placed by bonding strain gauges at certain locations on both faces of the pile to measure bending moment, from two-way loadings. Linear variable differential transformers(LVDTs) were installed to measure the lateral pile displacement. Based on this, it is found that the test single column/shaft with different free lengths shows different failure modes. If the test pile has a longer free length, the failure occurs at the near the ground surface, but the shorter one's failure occurs at the below the ground surface.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1112-1115
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• 2008

A very high current efficiency of 28 cd/A for three-mode microcavity tandem WOLED was successfully demonstrated. The 101 % of NTSCu'v' ratio of this white OLED with LCD color filter was achieved. In addition to wide color gamut, the highest delta (u'v') of respective RGB colors among the viewing angles 0 and 60 degree is just 0.042 and that of white color is less than 0.02.

• The Korean Journal of Rehabilitation Nursing
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• v.19 no.1
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• pp.64-70
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• 2016

Purpose: The purpose of this study was to identify awareness and knowledge about hepatitis B virus (HBV) infection among North Korean immigrants who had resided in South Korea. Methods: This was a cross-sectional, community based study. Data were collected from a convenience sample of 198 North Korean immigrants aged 18 years old through 65 years old among those who had attended community centers, local churches, and gathering places in four cities. The questionnaire included 15 items about participants' knowledge on HBV infection and its consequences, mode of transmission, and preventive measures. Results: The mean score of HBV knowledge was $6.3{\pm}3.8$ (range 0~15). The items that over 60% of the respondents checked correct answer regarding knowledge about HBV were 'There is blood screening for hepatitis B infection', 'Hepatitis B can be transmitted through sharing needles with infected person'. Multivariate analysis showed that received education for the prevention of HBV infection and disease morbidity were significantly associated with the knowledge of HBV infection. Overall, approximately 11% of total variability in the knowledge of HBV infection could be explained by the 2 variables in this model ($R^2=.109$, p<.001). Conclusion: The results showed that North Korean immigrants need more education on HBV infection and prevention to improve their knowledge about HBV.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.585-588
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• 2003

We have studied how rubbing direction affects generation of disclination line in transmissive microdisplay for $90^{\circ}$ twisted nematic (TN) mode with pixel size of $22.2{\mu}m$. The rubbing direction of bottom substrate is changed from $0^{\circ}$ to $-135^{\circ}$ with a decrease step of $45^{\circ}$, and the results show that the generation regions of the disclination line are of a smallest size in $-135^{\circ}$ direction. The results were the same although the pixel size decreased. Consequently, the use of proper rubbing direction of liquid crystal can help overcome the problems of low aperture ratio and low contrast ratio in transmissive-type microdisplays. In addition, the pretilt angle of initial liquid crystal is found to make an important contribution to generation of the disclination line.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2701-2703
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• 1999

A new mode of parallel operation of a modular 3-phase AC-DC Flyback converter for high power factor correction along with tight regulation is presented in this thesis. The converter offers input/output transformer isolation for safety, a unity input power factor for minimum reactive power, high efficiency and high power density for minimum weight and volume. Compared with previously developed 3-phase two-stage power converter, the advantage of the proposed converter does not require expensive high voltage and high current devices that are normally needed in popular boost type 3-phase converter. In this paper, a detailed small signal analysis of the modular 3-phase AC-DC flyback converter is provided for control purposes and also experimental results are included to confirm the validity of the analysis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.327-327
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• 2010

In this paper, an investigation of factors affecting piezoelectric transformers is presented by ATILA software. These transformers are multi-layer piezoelectric transformers in square shape $28\;{\times}\;28\;mm$ and operate in first vibration mode for step-down function. The piezoelectric transformers were modeled in 3D-dimension and analyzed using finite element method in ATILA software, a popular software in piezoelectric analysis. Modal and harmonic modules were used in this process. Effective factors to the properties of piezoelectric transformers including different input electrode patterns, directions of polarization, sizes of connective comer, number of layers were examined on the simulated model using input voltage of 20 V and load resistance of $100\;{\Omega}$. Moreover, thermal analysis was also obtained with conditions of input voltage of 5 V and no-load.

• Fashion & Textile Research Journal
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• v.4 no.2
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• pp.128-136
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• 2002

This research was designed to study the Korean dress design trends and different kinds of ancient patterns applied to the Korean dresses in 2001. The trend sources were collected by the HANBOK monthly journal and the symbolism of patterns associated with these patterns being used the prevalent Korean dress collection in markets. The results of the research can be summarized as following; The most of Korean dress image was elegant of ancient mode. Main colors of the traditional Korean jacket were white, yellowish white and green. However, main color of the traditional Korean skirt was represented as red. A plant pattern was the most popular pattern in a practical purpose. It looks beautiful and it is also easily manufactured with open space. Copying other patterns definitely damage the elegance of the Korean dress. It is time for us to not only keep our own traditions but also study and develop new patterns. Designers must study to develop the image and patterns which are agreed with consumer's taste.

• 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.