• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.5
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• pp.19-26
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• 2021

This report proposes a waveguide spatial combiner with high power low loss. The proposed spatial combiner implements high power by combining from the center of each port through a waveguide. In particular, we implement low loss using TE01 mode, which has the lowest transmission track loss among modes of circular waveguide, and miniaturization is achieved by applying a new mode conversion method. IIn addition, it was confirmed that it was suitable for high output by calculating the insulation breakdown voltage of the new mode conversion structure through E-field analysis. The final 8-way waveguide spatial combiner was designed and manufactured, and the insertion loss was less than 0.4dB and the combining efficiency was 97% or more, confirming that the electrical performance was very good compared to the planar combining method.

• Journal of the Korean Institute of Navigation
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• v.11 no.2
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• pp.53-59
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• 1987

This paper describes the design theory of a weakly-coupled Tap-off with high density of coupling intervals for CATV and/or MATV systems, by which the degree of freedom in design and density of coupling intervals are significantly increased compared with the intrinsic one. It is also described how to construct the two-way divider (Tap-off) in the generalized type. Furthermore, the practical measurements of the frequency characteristics for a fabricated circuit show very good agreements with theoretical results.

• Journal of Families and Better Life
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• v.11 no.2
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• pp.30-39
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• 1993

This study examined the relationship between marital cohesion adaptability and marital communication and especially tested the linear versus curvilinear hypothese with Circumplex Model. The subjects were 142 couples living in Pusan./ The data were analyzed using frequency one-way ANOVA and Pearson's correlation coefficient The major finding of this study were as follows: The relationship between the dimensions of cohesion adaptability and communica-tion was linear than curvilinear. High cohesion and high adaptability spouses were more effective communication than low cohesion and low adaptability.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.305-307
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• 2014

Pyroprocessing (or pyrometallurgy) is the way of extracting from materials subjected to high temperatures. Generally, this process has a high energy consumption because of mass production and heating-up. To attain effective and efficient energy management, energetic analysis using 0-dimensional model is usually conducted. However, this model can lead to a misunderstanding about energy evaluation due to many assumptions and limitations. In this study, heat & mass balance using 0-dimensional model was reviewed to systematize problems and considerations in general process energy evaluation.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.711-714
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• 2004

A new design for improving the aperture ratio of bottom emission type AMOLED is investigated. In conventional, the TFT of AMOLED fabrication method is "Etch Stopper (7-mask)", so the aperture ratio is limited in 28${\sim}$33% by Cs(Storage Capacitor). A high aperture ratio TFT is designed by using BCE(Back Channel Etching 5-mask) fabrication way and the aperture ratio is up to 40% shown in 2.2"AMOLED display.

• Korea-Australia Rheology Journal
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• v.21 no.2
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• pp.143-146
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• 2009

Breakthrough of high Weisenberg number problem is related with keeping the positive definiteness of the conformation tensor in numerical procedures. In this paper, we suggest a simple method to preserve the positive definiteness by use of vector decomposition of the conformation tensor which does not require eigenvalue problem. We also derive the constitutive equation of tensor-logarithmic transform in simpler way than that of Fattal and Kupferman and discuss the comparison between the vector decomposition and tensor-logarithmic transformation.

• Electrical & Electronic Materials
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• v.15 no.9
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• pp.10-14
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• 2002

Plasma processing plays a significant role in semiconductor devices technology. Development of new plasma systems, such as high-density plasma reactors, required development of plasma theory to understand a whole process mechanism and to be able to explain and to predict processing results. A most important task in this way is to establish interconnections between input process parameters (working gas, pressure flow rate input power density) and a various plasma subsystems (electron gas, volume and heterogeneous gas chemistry, transport), which are closely connected one with other. It will allow select optimal ways for processes optimizations.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.05a
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• pp.37-40
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• 2002

The purpose of this study is promote perfect of construction and progress of packing ability through comparison and analysis with quality, as placing ways and placing direction are changed. Kinds of concrete are general, high fluidity, and high Performance concrete. Classified with concrete as placing ways - direct ways, sheath way - and placing directing - flange direction, web direction - is analyzed section and strength of hardened concrete. The results of this study is belows the more fluid of concrete, the more useful to top-down method.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.778-782
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• 2007

Over 6 thousand workplaces in Korea are exposed to levels of noise which put their hearing of risk. Goverment considered various methods for noise reduction, but high noise breeds much problems still. This research investigates the present state of noise occurance and studied improvement way of administration system.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.638-644
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• 1999

Workability time of superplasticized concrete is maintained generally for 30-60 minutes only. Therefore it is of great advantage for the concrete producer to use a high range water reducer which provides an extended slump life. Recently slump retentive srperplasticizer has been developed. Concrete mixing tests were done to know slump, setting, air content, bleeding and hardening characteristics of concrete using slump retentive superplasticizer. With slump retentive superplasticizer, high quality concrete was produced and slump loss of concrete was reduced in big way, making long transportation time possible as a practical alternative to on-site addition.