• ETRI Journal
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• 제36권2호
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• pp.321-324
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• 2014

This letter describes a two-phase clock oxide thin-film transistor shift register that executes a robust operation over a wide threshold voltage range and clock coupling noises. The proposed circuit employs an additional Q generation block to avoid the clock coupling noise effects. A SMART-SPICE simulation shows that the stable shift register operation is established for the clock coupling noises and the threshold voltage variation from -4 V to 5 V at a line time of $5{\mu}s$. The magnitude of coupling noises on the Q(15) node and Qb(15) node of the 15th stage is respectively -12.6 dB and -26.1 dB at 100 kHz in the proposed circuit, compared to 6.8 dB and 10.9 dB in a conventional one. In addition, the estimated power consumption is 1.74 mW for the proposed 16-stage shift registers at $V_{TH}=-1.56V$, compared to 11.5 mW for the conventional circuits.

• 대한전자공학회논문지SP
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• 제49권1호
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• pp.1-10
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• 2012

본 논문은 물체 추적에 적합한 새로운 형식의 히스토그램 모델을 제안한다. 제안하는 색상 히스토그램은 양자화 된 각 색상요소에 대해 픽셀의 개수뿐만 아니라 평균 위치 정보 그리고 평균 위치로부터 일정하게 떨어진 영역에 속하는 픽셀들의 색상평균값을 포함한다. 또한 제안하는 히스토그램간의 유사도를 나타내기 위하여 Bhattacharyya 거리를 기본으로 새로운 유사도 함수를 정의하고 mean shift 기법에 적용한다. 기존의 mean shift 기반 기법들과는 달리 본 논문에서 제안하는 알고리즘은 물체 주변 배경 영역에 물체와 비슷한 색상이 존재하더라도 강건한 물체 추적이 가능하다. 실험 결과는 기존 기법들과의 비교를 통하여 개선된 추적 결과를 보여준다.

• 한국전자통신학회논문지
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• 제8권9호
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• pp.1319-1324
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• 2013

Mean-Shift 알고리즘은 목표모델과 후보영상 사이의 컬러분포의 유사도를 이용하는 국부적 탐색기법으로서, 그 기법의 단순성 및 안정성 면에서 뛰어나 얼굴추적에 많이 이용되고 있다. 그러나 컬러분포를 이용한 얼굴추적은 목표모델과 유사한 컬러분포를 갖는 객체나 배경의 영향에 취약하다. 또한 얼굴 추적에서 결정되는 얼굴영역은 얼굴인식 혹은 얼굴방향 등을 계산할 때 중요한 단서가 되는데, 완전히 다른 컬러분포를 갖는 객체의 가려짐으로 얼굴영역의 크기나 위치가 변동될 위험이 있다. 대체로 거리정보는 얼굴과 배경의 구분에 효율적이고 컬러정보는 객체 구분에 유리하다는 가정으로부터, 본 논문에서는 이러한 문제를 해결하기 위해 거리 정보와 컬러 정보를 함께 이용하는 양방향 필터를 고안하고, 이것을 Mean-Shift 알고리즘에 활용하였다. 일련의 실험을 통해 성공적인 실험결과를 얻었다.

• PNF and Movement
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• 제17권1호
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• pp.93-101
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• 2019

Purpose: This study aimed to investigate lower extremity muscle activation to the variable weight shift on the affected side of patients with hemiplegia. Methods: Eighteen patients with chronic hemiplegia volunteered to participate in this study. All participants performed three types of weight shift (sideways, forward, and backward) in limits of stability on the affected side. Muscle activation in a paralyzed leg was measured with electromyography on the gluteus medius, tensor fasciae latae, rectus femoris, and biceps femoris; furthermore, the attached area was recommended by SENIAM projects. Each weight shift was performed three times, and then the mean value of the three measurements was analyzed. The data were analyzed by measuring the symmetrically standing position with the reference voluntary contraction (RVC) and was standardized with the percentage of RVC method. Results: No significant difference in lower extremity muscle activation occurred according to the three types of variable weight shift. However, significant differences in lower extremity muscle activation did occur with each weight shift position. In addition, activation increased at the rectus femoris and decreased at the gluteus medius and tensor fasciae latae. Conclusion: Hip abductor muscle strength training and variable weight shifts on the affected side must increase to improve patients'balance and limits of stability.

• 지구물리와물리탐사
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• 제27권2호
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• pp.129-143
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• 2024

자기지전류(magnetotelluric, MT) 탐사 시, 지표면 부근의 작은 불균질체가 존재할 경우 겉보기비저항이 주파수와 무관하게 이동하는 정적효과(static shift)가 발생한다고 알려져 있다. 이러한 정적효과가 자료에 포함되어 있으면 지하 구조 해석에 오류가 발생하기 때문에 정적효과에 의한 왜곡을 해결하기 위한 연구가 지난 수십년 동안 수행되어 왔다. 가장 대표적인 방법으로는 역산 전에 MT 자료에서 정적효과를 제거하기 위해 보정하는 방법이 있다. 이와 달리, 역산 과정에서 정적효과를 역산의 변수로 포함시켜 그 크기를 추정하거나 따로 정적효과를 추정하지 않고 역산 과정에서 보정을 수행하기도 한다. 이외에도 다른 물리탐사 기법을 통해 얻은 자료를 사용하여 MT 탐사 정적효과를 제거할 수 있다. 하지만 지금까지 연구된 보정법들은 1차원적인 정적인 반응에만 국한되어 있어 2차원이나 3차원의 자료를 역산하고 해석하는 데에는 여전히 한계가 있다. 이 논문에서는 지금까지 MT 자료에서 정적효과를 처리하는 여러 방법들에 대해 분석하여 향후 정적효과 관련 연구를 위한 기초를 제공하고자 한다.

• Journal of Microbiology and Biotechnology
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• 제15권3호
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• pp.568-572
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• 2005

Saccharomyces yeast spores are more resistant to drying and storage than vegetative cells. For the mass production of yeast spores, compressed yeast was directly inoculated into a sporulation medium (SM). The effects of inoculum size and the addition of rice wine cake (RWC) into SM on the sporulation were examined using flasks. With $1\%$ inoculum of compressed yeast, $1.45{\times}10^8/ml$ of asci was obtained. The addition of $0.5\%$ RWC into SM improved the cell growth and spore yield, and the number of asci formed was $2.31{\times}10^8/ml$. The effects of culture temperature, temperature-shift, and concentrations of inoculum, potassium acetate, and RWC on the sporulation were also evaluated using a jar fermentor. The optimum temperature for spore formation was $22^{\circ}C$ where the number of asci formed was $2.46{\times}10^8/ml$. The shift of culture temperature from initial $30^{\circ}C$ for 1 day to $22^{\circ}C$ for 3 days increased the number of asci formed to $2.96{\times}10^8/ml$. The use of $2\%$ (w/v) inoculum of compressed yeast, $2\%$ potassium acetate, and $1\%$ (w/v) RWC in SM with the shift of culture temperature of initial $30^{\circ}C\;to\;22^{\circ}C$ resulted in $90\%$ sporulation ratio and formation of $6.18{\times}10^8\;asci/ml$.

• Journal of electromagnetic engineering and science
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• 제12권4호
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• pp.280-286
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• 2012

The conventionally classified waves are reclassified in this paper, including the waves associated with metamaterial (MTM) transmission lines. Various types of guided waves in periodic structures are analyzed for 1D Composite Right/Left Handed (CRLH) transmission lines (TL). In addition, dispersion diagrams for 1D CRLH, RH, and LH TLs are presented in terms of radiation conditions. We have refined the design equations of the conventional 1D CRLH TL and proposed a condition to realize the desired phase shift and its slope per unit cell. This condition has been applied to the conventional Wilkinson power divider and realized into MTM added $90^{\circ}$ hybrid coupler. Based on the 10 dB return loss and the $90{\pm}10^{\circ}$ phase shift, the bandwidths of the MTM added $90^{\circ}$ hybrid coupler are 82.25% and 103.5% against the conventional 23% and 52.5%, respectively.

• 한국생산제조학회지
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• 제25권1호
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• pp.21-29
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• 2016

To overcome the large ring gear manufacturing problems seen in slewing bearings and girth gears, pin gear drive units have been developed. Among them, a novel slewing bearing with an internal pinwheel gear set (i-PGS) is introduced in this paper. First, we consider the exact cam pinion profile of i-PGS with the introduction of a profile shift coefficient. Furthermore, a new root relief profile modification for the i-PGS cam pinion is presented. Then, the contact stresses are investigated to determine the characteristics of the surface fatigue by varying the shape design parameters. The results show that the contact stresses of i-PGS can be reduced significantly by increasing the profile shift coefficient. In addition, the contact ratio, a measure of teeth overlapping action, decreases with the decrease of the allowable pressure angle.

• Journal of Electrical Engineering and Technology
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• 제12권4호
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• pp.1529-1536
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• 2017

A digital dual-channel interleaved phase-shift full-bridge converter is investigated in this paper, and its topology and principle are analyzed. To realize current sharing and stabilize the output voltage, a controller with current sharing loop and closed voltage loop is employed. In addition, current sharing will increase the output current fluctuation and a new digital interleaved driving technology is proposed to reduce the output current ripple. To verify the analysis, simulation and experiments are carried out, which shows the effectiveness of the proposed control strategies.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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• pp.1973-1974
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• 2006

The mean shift algorithm has achieved considerable success in object tracking due to its simplicity and robustness. It finds local maxima of a similarity measure between the color histograms of the target and candidate image. However, the mean shift tracking algorithm using only color histograms has a serious defect. It doesn't use the spatial information of the target. Thus, it is difficult to model the target more exactly. And it is likely to lose the target during the occlusions of other objects which have similar color distributions. To deal with these difficulties we use both color information and spatial information of the target. Our proposed algorithm is robust to occlusions and scale changes in front of dynamic, unstructured background. In addition, our proposed method is computationally efficient. Therefore, it can be executed in real-time.