• Journal of Advanced Marine Engineering and Technology
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• v.32 no.6
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• pp.964-973
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• 2008

In this study, a short-wavelength coplanar-type transmission line employing periodic ground structure (PGS) was developed for application to miniaturized on-chip passive component on Si Radio Frequency Integrated Circuit (RFIC). The transmission line employing PGS showed shorter wavelength and lower characteristic impedance than conventional coplanar-type transmission line. The wavelength of the transmission line employing PGS structure was 57 % of the conventional coplanar-type transmission line on Si substrate. Using the theoretical analysis. basic characteristics of the transmission line employing PGS (e.g., bandwidth. loss, impedance, and resonance characteristics) were also investigated in order to evaluate its suitability for application to a development of miniaturized passive on-chip components on silicon RFIC. According to the results. the bandwidth of the transmission line employing PGS was more than 895 GHz as long as T is less than 20${\mu}m$, and the resonance characteristic was observed in 1239 GHz, which indicates that the PPGM structure is a promising candidate for application to a development of miniaturized on-chip passive components on Si RFIC.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.6
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• pp.1099-1104
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• 2007

A 1:6 Unequal 2-way Wilkinson power divider is proposed. The required microstrip line with $207{\Omega}$ characteristic impedance for 1:6 power divider is realized by adding defected ground structure (DGS) to the standard microstrip line. The adopted DGS has the rectangular geometry which results in the increased characteristic impedance. The rectangular-shaped DGS produces the transmission line having much higher characteristic impedance due to the increased equivalent inductance. The measured performances of the fabricated 1:6 power divider show the expected S-parameters with a good agreement with the predicted ones.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.197-202
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• 2005

In this paper, we analyzed the signal distortion incorporating meander-shaped transmission line on PCB in broadband frequency range, up to 50GHz. This broadband characteristic provides reasonable analysis of digital pulse having very short rising time. Simulation results reveal suppression characteristic at multiband which is dependent on only the width of meander arm. This width of arm also can be adjusted using different permittivity because it provides different effective wave-length. It is found that the suppression characteristic shows sharpness with as a function of the number of arms. However, these characteristics shown limitation for microstrip line structure rather than for stripline structure, so we can avoid these unwanted phenomena using stripline structure.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.5
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• pp.295-304
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• 2004

This paper deals with characteristic analysis method using d-q axis equivalent circuit considering iron loss in a single-phase line-start permanent magnet synchronous motor. The iron loss resistance to account for the iron loss is included in the equivalent circuit to improve the modeling accuracy. Furthermore, for the improved calculation of the iron loss, the iron loss is calculated from the magnetic flux density by 2-dimensional finite element method. The result is represented as the iron loss resistance and connected in parallel with the total induced voltage. Therefore, the currents can be expressed as the summation the output current with the current corresponding to the iron loss. Finally, the steady state characteristic analysis results are compared with the experimental results to verify this approach.

• Proceedings of the KIEE Conference
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• 2005.10c
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• pp.235-237
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• 2005

This study investigates Characteristic analysis of Line-start Synchronous Reluctance Motor to substitute for Induction Motor. The results of machine characteristics are analyzed by simulation using Flux2D. Characteristic analysis result of Line-start Synchronous Reluctance Motor is confirmed by the Experimental result.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.933-935
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• 2005

This study investigates Characteristic analysis of Line-start Synchronous Reluctance Motor to substitute for Induction Motor. The results of machine characteristics are analyzed by simulation using Flux2D. Characteristic analysis result of Line-start Synchronous Reluctance Motor is confirmed by the analysis result of 3-Phase Induction Motor.

• Korean Journal of Human Ecology
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• v.19 no.1
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• pp.137-147
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• 2010

This research was designed to compare the subjective evaluation of texture image and preference by structure and sensible characteristics of women's suits fabrics between on- and off-line. 78 subjects who majored in fashion design evaluated the sensibility image and preference of 15 various kinds of specimens on- and off-line. Factor analysis, t-test, Pearson correlation and regression were used for a statistical analysis by SPSS WIN 13.0. The results of this study were as follows: 1. Women's suits fabrics were classified according to five sensibility image factors: 'classic', 'sophisticated', 'natural', 'characteristic', and 'practical'. 2. The results of the t-test showed that there were no differences between the on- and off-line evaluation of sensibility images. 3. The analysis of correlation indicated that the 'classic'-'sophisticated' and 'natural'- 'practical' sensibility images show a significant correlation between the two kinds of evaluation. 4. The results of regression revealed that 'sophisticated', 'characteristic' and 'practical' sensibility images had an effect on the purchase preference of women's suits fabrics. 5. 'Sophisticated', 'characteristic' and 'classic' sensibility images had an effect on the tactile preference of women's suits fabrics. 6. The structural characteristics of fabrics: thickness, weave and weight had an effect on the 'classic' sensibility image. Thickness had an effect on the 'sophisticated' sensibility image and fabric count had an effect on the 'characteristic' sensibility image.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.3_4
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• pp.310-321
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• 2003

The purpose of this study is clarify the formative characteristic of dance costume design and analyse stage effect based upon the formative factors. Classified design element of dance costumes by line, silhouette, color, material, lighting, and also this based on content analysis method about each formative factor of costumes that showed 10 dance performances which practically be performed and made. And individually interviewed the professional dance composers and dancers who participated in the performances fer objectivity and specialty of this study. The results were as follows; 1. Dance costume contains and harmoniously expresses theme of a dance work, formative characteristic of fashion design, movement and character of the dancers, lighting effect. 2. Korean creative dance costume is effectively expressed with formative factors of traditional costumes and modem sensibility and symbolic expression of image-centered. 3. Costume line is affected by dancer's movement and it's possible to be different effect that the atmosphere or stage effect by the original form of line and the expression method. 4. Costume color is effective to inform that dancer's character and image of a dance work. 5. Costume material is most important to consider that the dancers and the atmosphere and the image of a dance work. 6. Lighting effect can inform various feel of dancer's dance.

• Journal of electromagnetic engineering and science
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• v.9 no.2
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• pp.85-97
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• 2009

As operating frequency is raised and as more integration with active and passive elements is required, it becomes difficult to fabricate more than 120 ${\Omega}$ characteristic impedance of a mierostrip line. To solve this problem, an equivalent high impedance transmission-line section is suggested, which consists mainly of a pair of coupled-line sections with two shorts. However, it becomes a transmission-line section only when its electrical length is fixed and its coupling power is more than half. To have transmission-line characteristics(perfect matching), independently of coupling power and electrical length, two identical open stubs are added and conventional design equations of evenand odd-mode impedances are modified, based on the fact that the modified design equations have the linear combinations of conventional ones. The high impedance transmission-line section is a passive component and therefore should be perfectly matched, at least at a design center frequency. For this, two different solutions are derived for the added open stub and two types of high impedance transmission-line sections with 160 ${\Omega}$ characteristic impedance are simulated as the electrical lengths of the coupled-line sections are varied. The simulation results show that the determination of the available bandwidth location depends on which solution is chosen. As an application, branch-line hybrids with very weak coupling power are investigated, depending on where an isolated port is located, and two types of branch-line hybrids are derived for each case. To verify the derived branch-line hybrids, a microstrip branch-line hybrid with -15 dB coupling power, composed of two 90$^{\circ}$ and two 270$^{\circ}$ transmission-line sections, is fabricated on a substrate of ${\varepsilon}_r$= 3.4 and h=0.76 mm and measured. In this case, 276.7 ${\Omega}$ characteristic impedance is fabricated using the suggested high impedance transmission-line sections. The measured coupling power is -14.5 dB, isolation and matching is almost perfect at a design center frequency of 2 GHz, showing good agreement with the prediction.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.8
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• pp.61-67
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• 2010

A characterization procedure for analyzing symmetric coupled MIS(Metal-Insulator-Semiconductor) transmission line is used the same procedure as a general single layer symmetric coupled line with perfect dielectric substrate from the extraction of the characteristic impedance and propagation constant for even- and odd-mode. In this paper, an analysis for a new substrate shielding symmetric coupled MIS structure consisting of grounded crossbar at the interface between Si and SiO2 layer using the Finite-Difference Time-Domain (FDTD) method is presented. In order to reduce the substrate effects on the transmission line characteristics, a shielding structure consisting of grounded crossbar lines over time-domain signal has been examined. Symmetric coupled MIS transmission line parameters for even- and odd-mode are investigated as the functions of frequency, and the extracted distributed frequency-dependent transmission line parameters and corresponding equivalent circuit parameters as well as quality factor for the new MIS crossbar embedded structure are also presented. It is shown that the quality factor of the symmetric coupled transmission line can be improved without significant change in the characteristic impedance and effective dielectric constant.