• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.4
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• pp.561-570
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• 2018

This study defined the changes of mechanical properties of silk fabric according to bias angles and investigated the influence of bias angles and fabric characteristics on hand value. For the experiments, 4 types of commercial silk plain weave fabrics were chosen. All fabrics had the same density, but different yarn characteristics. Fabric samples were cut into 12 different bias angles between $0^{\circ}$ and $165^{\circ}$ with $15^{\circ}$ gap and measured for tensile, shear, bending, surface properties by the KES-FB system. As a result, most mechanical parameters showed an asymmetry shape with $90^{\circ}$. The most flexible and easiest angles are $45^{\circ}$, $135^{\circ}$. Furthermore, the bias angles of silk fabrics were classified into three clusters with mechanical properties such as WT, 2HG, 2HG5, B, and SMD. The parameters according to fabric samples showed significant differences at WT, RT, B, 2HB, and MIU. It showed bigger effects as yarn fineness; in addition, twists were higher except RT. The results of hand value indicated that Koshi and Hari were highest with a bias angle of $75^{\circ}$; however, Shinayakasa was highest at bias angle of $45^{\circ}$. Finally, Shari was lowest at $45^{\circ}$.

• The Research Journal of the Costume Culture
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• v.4 no.1
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• pp.93-109
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• 1996

Madeleine Vionnet, a representative designer of the 1920′s, who made prefectly organized clothes with unique formativeness was the first to express fabric in a modern method and was called "The architect of fashion". This is because she developed a three dimensional design by expressing cloth-she rejected corset, should pad, etc-into elegant curved lines that do not stick to the body. By granting meaning to the beauty of the body and its movement in her own unique ways, she emphasized the formativeness in her work and gave shape to creative artistry. Expecially with the "Bias-Cut" she could express the lines of the body more flexibly and could make geometrical styles like the diamond shape dress or the triangle dress more effectively. Using the "Tired Bias cut" and "Handkerchief point" she let the skirt hemline dangle irregularly in geometrical forms, thus showing modern formative sense which forms a three dimensional solidness along the movement of the human body. Thus far, analyzed how the contemporary trend of art was reflected in her designs by studying her work; also investigated through her artistic characteristics and pattern method. Also be tried to find out what can be learned through her artistic view and superb formativeness as a designer.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.29-33
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• 2002

본 논문은 자기 바이어스(self bias)를 이용한 PCS 대역용 하이브리드 전력 저잡음 증폭기(power LNA) 모듈에 관한 것으로 GaAs p-HEMT 칩을 세라믹 기판에 실장하여 와이어 본딩과 주변 매칭을 통해 고주파 손실을 줄이고 온도 변화에 대한 안정성과 1.2㏈의 저잡음, 21~23㏈m의 P$_1$㏈를 실현하였다. 10mm$\times$10mm 크기로 표면 실장이 되도록 단자를 cut-line 형태로 모듈화 하여 안정성과 신뢰성을 향상시켰고 또한 저가격화를 실현하였다.

• Advances in nano research
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• v.15 no.3
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• pp.263-275
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• 2023

The electron transport properties of Y-type zigzag branched carbon nanotubes (CNTs) are of great significance for micro and nano carbon-based electronic devices and their interconnection. Based on the semi-empirical method combining tight-binding density functional theory and non-equilibrium Green's function, the electron transport properties between the branches of Y-type zigzag branched CNT are studied. The results show that the drain-source current of semiconducting Y-type zigzag branched CNT (8, 0)-(4, 0)-(4, 0) is cut-off and not affected by the gate voltage in a bias voltage range [-0.5 V, 0.5 V]. The current presents a nonlinear change in a bias voltage range [-1.5 V, -0.5 V] and [0.5 V, 1.5 V]. The tangent slope of the current-voltage curve can be changed by the gate voltage to realize the regulation of the current. The regulation effect under negative bias voltage is more significant. For the larger diameter semiconducting Y-type zigzag branched CNT (10, 0)-(5, 0)-(5, 0), only the value of drain-source current increases due to the larger diameter. For metallic Y-type zigzag branched CNT (12, 0)-(6, 0)-(6, 0), the drain-source current presents a linear change in a bias voltage range [-1.5 V, 1.5 V] and is symmetrical about (0, 0). The slope of current-voltage line can be changed by the gate voltage to realize the regulation of the current. For three kinds of Y-type zigzag branched CNT with different diameters and different conductivity, the current-voltage curve trend changes from decline to rise when the branch of drain-source is exchanged. The current regulation effect of semiconducting Y-type zigzag branched CNT under negative bias voltage is also more significant.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.633-636
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• 1998

In this study, power AlGaAs/InGaAs/GaAs PM-HEMT's for mm wave's were fabricated using Electron beam lithography and air-bridge techniques, and so on. DC and AC characteristics of the fabricated power PM-HEMTs were measured under the various bias conditions. For example, DC and RF characteristics such as S21 gain of 3.6 dB at 35 ㎓, current gain cut-off frequencies of 45 ㎓ and maximum oscillation frequencies of 100 ㎓ were carefully analyzed for design methodology of sub-mm wave power devices.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.273-276
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• 2002

In this paper, we propose a bias random vector generator which can verify functions of microprocessor effectively. This generator is a pre-processor of assembly program, and defines pre-processor instructions which create random vector only in the pall which the designer wants to verify. Therefore, this generator shows higher detection ration than any other generators. And, we can cut down design costs because of shortening a Period for verifying function.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.121-124
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• 2002

In this paper, we propose a bias random vector generator which can verify functions of microprocessor effectively. This generator is a pre-processor of assembly program, and defines pre-processor instructions which create random vector only in the part which the designer wants to verify. Therefore, this generator shows higher detection ration than any other generators. And, we can cut down design costs because of shortening a period for verifying function.

• The Research Journal of the Costume Culture
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• v.18 no.3
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• pp.465-475
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• 2010

For this study, 18 kinds of cut and sew or seamless knitted test garment were made. Samples differed from each other by skirt angles($90^{\circ}$, $180^{\circ}$), gauges(7G, 12G, 15G), and grain directions(bias direction, wale direction, and radial direction). After measuring the mechanical properties of various gauges on the seamless knitting machine, I compared shape of the knitted flare skirt through subjective evaluation on appearances. The data analysis methods used in this study were descriptive statistics, one-way ANOVA, Duncan-test, correlation analysis, and regression analysis. The subjective evaluation on appearances of knitted flare skirts showed the following: In case of $90^{\circ}$ skirt, the seamless skirt showed a much higher score in every gauge expect that of the cut and sew 12G, and silhouette of 15G wale direction. In case of the $180^{\circ}$ skirt, the seamless type showed a much higher score in every item over the cut and sew expect the silhouette part of 7G wale direction.

• The Korean Journal of Applied Statistics
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• v.33 no.4
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• pp.409-420
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• 2020

In business survey, modified cut-off sampling is commonly used to greatly increase the accuracy of the estimation while reducing the number of samples. However, non-response rate of take-all stratum has increased significantly and the sample substitution is not possible because the non-response in the take-all stratum affects the accuracy of the estimation. It is important to adjust the bias appropriately if non-response is affected by the variable of interest. In this study, a bias adjusted estimation is proposed as an appropriate method to deal with a non-response in the take-all stratum. In particular, the estimator proposed by Chung and Shin (2020) was applied to the bias adjustment for the take-all stratum; therefore, we suggest a new method to adjust properly for the take-all stratum. The superiority of the proposed estimator was examined through simulation studies and confirmed through actual data analysis.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.1
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• pp.83-88
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• 2002

To increase the device linearities and the breakdown-voltages of FETs, $Al_{0.25}$G $a_{0.75}$As/I $n_{0.25}$G $a_{0.75}$As/A $l_{0.25}$G $a_{0.75}$As partially doped channel FET(DCFET) structures are proposed. The metal insulator-semiconductor(MIS) like structures show the high gate-drain breakdown voltage(-20V) and high linearities. We propose a partially doped channel structure to enhance the device linearity to the homogeneously doped channel structure. The physics of partially doped channel structure is investigated with 2D device simulation. The devices showed the small ripple of the current cut-off frequency and the power cut-off frequency over the wide bias range. bias range.