• 복식문화연구
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• 제20권4호
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• pp.594-603
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• 2012

This study aimed to investigate a bias pattern making method with geometrical approach. The bias-cut dress has soft silhouette of drape in the garment. However, the bias cut dress has problem of satisfying the intended garment size spec. This problem occurs from various sources. The main reason is that the bias-cut fabric tends to stretch on longitudinal direction and to shrink horizontal direction when it was hung on the body. The goal of this study was to develop a bias-cut dress pattern making method satisfying the intended garment size spec. The researchers developed the geometrical method of measuring dimensional change by calculating the compensation ratio of the fabric in true bias direction. The compensation ratio was calculated by applying draping ratio of the fabric. Three types of fabrics were used in the experiment. The warp and weft crossing angle of fabric was ranged from $78^{\circ}$ to $82^{\circ}$. The fabrics stretched longitudinally 6.9~9.9% and shrank horizontally 7.2~11.0%. The compensation ratio of the bias-cut pattern for sample dress was calculated for each fabric type. Two types of experimental bias-cut dress patterns were developed for each fabric. One pattern was made with applying full compensation ratio and the other one made with applying partial ratio of the fabric. Experimental dresses were made with these patterns. The results of the evaluation showed that the bias-cut dress pattern applying the partial compensation ratio was more appropriate than the pattern applying the full compensation ratio.

• 한국전기전자재료학회논문지
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• 제24권5호
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• pp.364-369
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• 2011

Analyzing electrical degradation of polycrystalline silicon transistor to applicable at several environment is very important issue. In this research, after fabricating p channel poly crystalline silicon TFT (thin film transistor) electrical characteristics were compare and analized that changed by gate bias with first measurement. As a result on and off current was reduced by variation of gate bias and especially re duce ratio of off current was reduced by $7.1{\times}10^1$. On/off current ratio, threshold voltage and electron mobility increased. Also, when channel length gets shorter on/off current ratio was increased more and thresh old voltage increased less. It was cause due to electron trap and de-trap to gate silicon oxide by variation of gate bias.

• 한국표면공학회지
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• 제29권3호
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• pp.149-156
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• 1996

Conducting diamond-like carbon films are synthesized using Triode Magnetron Sputtering-Plasma Enhanced Chemical Vapor Deposition(TMS-PECVD), and are examined by four point probe, microhardeness tester, and scanning electron miscroscopy(SEM). As the target bias and Ar/CH$_4$, ratio increase, the electrical resitivity and microhardness of the films are found to decrease, and also, their surface morphologies tend to be rough. While the resistivities of the films are shown to increase in proportion to the increase of the substrate bias, the microhardness of the films is shown to be maximun value(1600kg/$\textrm{mm}^2$) at a certain substrate bias(-70V). We can obtain the conducting diamond-like carbon films with the microhardness of 1600(kg/$\textrm{mm}^2$) and electrical resitivity of 16($\Omega$cm) at the process condition such as target bias -400V, substrate bias -70V, and Ar/$CH_4$ ratio 20.

• 한국수자원학회논문집
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• 제53권3호
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• pp.201-214
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• 2020

본 연구에서는 듀얼칼만필터를 이용하여 이중편파 레이더 강우의 편의를 실시간으로 보정할 수 있는 방법을 제안하였다. 듀얼칼만필터는 기존의 칼만필터와 달리 두 개의 시스템(상태추정시스템, 모형추정시스템)이 동시에 가동되면서 실시간으로 상태변수가 예측된다. 강우강도 추정치에 보정계수를 적용함으로써 편의보정이 이루어지며, 보정계수는 듀얼칼만필터의 상태-공간모형에 의해 실시간으로 예측된다. 해당 기법을 2016년 7월에 발생한 지속시간이 긴 호우사상에 대해 적용하고 편의보정 결과를 평가하였다. 먼저, 보정계수는 대부분 1과 2 사이의 값으로 산정되어 지상관측 강우강도보다 레이더 강우강도가 약간 과소추정되는 경향을 보였다. 보정계수에 대한 시계열을 설명할 수 있는 모형으로는 AR(1) 모형이 적합한 것으로 확인되었다. 아울러 듀얼칼만필터로 예측한 보정계수는 관측된 자료를 이용하여 산정한 보정계수와 유사한 경향을 가지는 것으로 나타났다. 칼만필터와의 비교 결과, 보정계수의 변동성이 커질수록 듀얼칼만필터가 칼만필터에 비해 우수한 예측 성능을 가지는 것으로 확인되었다. 본 연구를 통해 강우의 변동성이 크고, 지속시간이 긴 호우사상에 대한 듀얼칼만필터의 적합성이 검증되었다.

• Journal of the Korean Data and Information Science Society
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• 제17권4호
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• pp.1029-1039
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• 2006

There are different kinds of methods to estimate the odds ratio for unemployment statistics in small areas, namely, the composite estimator, the Woolf estimator and the Mantel-Haenszel estimator. We can compare the reliability of these estimators according to the bias and MSE. The estimation procedures considered by this study have been applied to estimate the bias and MSE of the odds ratio between the male and female unemployment rate in some small areas. The Woolf estimator or the Mantel-Haenszel estimator is more stable than the composite estimator, but all these three estimators are similar to each other from the aspect of efficiency.

• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1377-1383
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• 2005

In a cDNA microarray experiment using Cy3 and Cy5 as labeling agents, particularly for the direct design, cDNAs from some genes incorporate one dye more efficiently than the other, which is referred to as the gene-specific dye bias. Dye-swaps, in which two dyes are switched on replicate arrays, are commonly used to control the gene-specific dye bias. We developed a simple procedure to extract the gene-specific dye bias information from a partial dye swap experiment. We detected gene-specific dye bias by identifying outliers in an X-Y plane, where the X axis represents the average log-ratio from two sets of dye swap pairs and the Y axis exhibits the average log ratio of four forward labeled arrays. We used this information for detecting differentially expressed genes, of which the additionally detected genes were validated by real-time RT-PCR.

• Current Optics and Photonics
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• 제5권2호
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• pp.173-179
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• 2021

The electroluminescence (EL) intensities of GaN-based light-emitting diodes (LEDs) are estimated based on their photoluminescence (PL) properties. The PL intensity obtained under open-circuit conditions is divided into two parts: the PL intensity under a forward bias lower than the optical turn-on voltage, and the difference between the PL intensities under open-circuit conditions and under forward bias. The luminescence induced by photoexcitation under a constant forward bias lower than the optical turn-on voltage is primarily the PL from the excited area of the LED. In contrast the intensity difference, obtained by subtracting the PL intensity under the forward bias from that under open-circuit conditions, contains the EL induced by the photocarriers generated during photoexcitation. In addition, a reverse photocurrent is generated during photoexcitation under constant forward bias across the LED, and can be correlated with the PL-intensity difference. The relationship between the photocurrent and PL-intensity difference matches well the relationship between the injection current and EL intensity of LEDs. The ratio between the photocurrent generated under a bias and the short-circuit current is related to the ratio between the PL-intensity difference and the PL intensity under open-circuit conditions. A relational expression consisting of the ratios, short-circuit current, and PL under open-circuit conditions is proposed to estimate the EL intensity.

• Applied Science and Convergence Technology
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• 제23권3호
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• pp.145-150
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• 2014

MgO thin films were deposited by internal ICP-assisted reactive-magnetron sputtering with bipolar pulse bias on a substrate to suppress random arcs. Mg is reactively sputtered by a bipolar pulsed DC power of 100 kHz into ICP generated by a dielectrically shielded internal antenna. At a mass flow ratio of $Ar/O_2$ = 10 : 2 and an ICP/sputter power ratio of 1 : 1, optimal film properties were obtained (a powder-like crystal orientation distribution and a RMS surface roughness of approximately 0.42 nm). A bipolar pulse substrate bias at a proper frequency (~a few kHz) prevented random arc events. The crystalline preferred orientations varied between the (111), (200) and (220) orientations. By optimizing the plasma conditions, films having similar bulk crystallinity characteristics (JCPDS data) were successfully obtained.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.243-245
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• 1994

We synthesized the conducting diamond-like carbon films using plasma-enhanced chemical vapor deposition and analysized its characteristics. We obtained the metal-containing diamond-like carbon films using $CH_4$, Ar gas and aluminum target. We observed the changes of electrical conductivity, microhardness and surface morphology according to $Ar/CH_4$ ratio, substrate bias and target bias. As the target bias and $Ar/CH_4$ ratio increase and the substrate bias decreases, the electrical conductivity and surface roughness increase. The increase of hardness involves decrease of the electrical conductivity. Metal-containing amorphous hydrogenated carbon films show improved adhesion on metal substrates compared to pure diamond-like carbon films and better electrical conductivity.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.84-87
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• 2006

본 연구는 Current Mirror에 있어서 Active Current Bias에 관하여 기술하였다. Current mirror에서 Active Current Bias를 걸어주는 보편적인 방법은 Current Bias단에 저항을 연결하여 저항값을 조절함으로 해서 Current를 제어하는 방법을 사용한다. Reference 전류를 제어하는데 있어 새로이 제안하는 것은 Flyback Converter를 이용하여 Acitve Current Bias를 제어 하려 한다. 트랜지스터를 이용하여 Current Mirror Circuit를 구성하고 Current Bias 측에 Flyback Converter Circuit을 연결한다. Flyback Converter의 PWM의 Duty Ratio를 조절함으로 해서 전류를 제어하는 특징을 이용하여 Active Current Bias를 제어한다.