• 제어로봇시스템학회논문지
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• 제10권11호
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• pp.1082-1088
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• 2004

This paer presents a feedback-controlled, MEMS-fabricated microaccelerometer($\mu$XL). The $\mu$XL has received much commercial attraction, but its performance is generally limited. To improve the open-loop performance, a feedback controller is designed and experimentally evaluated. The feedback controller is applied to the x/y-axis $\mu$XL fabricated by sacrificial bulk micromachining(SBM) process. Even though the resolution of the closed-loop system is slightly worse than open-loop system, the bandwidth, linearity, and bias stability are stability are significantly improved. The noise equivalent resolution of open-loop system is 0.615 mg and that of closed-loop system is 0.864 mg. The bandwidths of open-loop and closed-loop system are over 100Hz. The input range, non-linearity and bias stability are improved from $\pm10\;g\;to\;\pm18g$, from 11.1%FSO to 0.86%FSO, and from 0.221 mg to 0.128 mg by feedback control, respectively.

• 한국음향학회지
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• 제35권1호
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• pp.35-41
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• 2016

본 논문에서는 상관함수와 최소자승 기법에 기반하여 단일 음원의 위치가 원거리 혹은 근거리 모두 가능한 경우, 이에 상관없이 닫힌 형태로 위치를 추정하는 기법을 제안한다. 최근 균일 환영 배열에서 상호상관함수를 이용하여 원거리 단일 음원의 위치를 2차원으로 추정하는 기법이 제안되었으며, 이를 확장하여 근거리 단일 음원의 위치를 3차원으로 추정하는 기법이 제안되었다. 그러나 기존 기법은 음원의 위치가 원거리, 혹은 근거리로 제한된 상황만 다루고 있다. 반면 제안 기법은 먼저 원거리 음원으로 가정하여 거리 독립적으로 방위와 고각을 구하고 이후 거리 추정에서 원거리와 근거리 음원을 구분하여 혼합 환경에 적용가능하다. 시뮬레이션에서는 두 가지 경우 모두에 대해 실험하여 제안 기법의 타당성을 검증하였다.

• Clinics in Shoulder and Elbow
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• 제8권2호
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• pp.181-186
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• 2005

An anterior dislocation of the elbow without a fracture of the olecranon is an extremely rare injury. This paper reports a 36-year-old male who stumbled and fell on his outstretched hand during a soccer game. The anteroposterior and lateral radiographs indicated a simple anterior dislocation of the elbow, which was reduced using a closed method. The elbow joint was stable in the range of motion, but the sensation of the two ulnar digits was still reduced. MRI was useful for the identification of the pathoanatomy. At the follow-up examination three months after the initial trauma, the hypesthesia has fully recovered and the patient regained the full range of the elbow and forearm motion without pain and instability. After 18 months, the patient had a normal elbow function, and could play various sports. If an anterior elbow dislocation is detected early, a closed reduction with careful pathoanatomical considerations would be successful.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.597-602
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• 2008

The experiment of performance about closed-wet cooling tower(CWCT) was conducted in this study. The test section has the cooling water that flows from top part of a heat exchanger that has an entrance of cooling water with one and multi path. The heat exchanger consists of 15.88mm tubes with ten rows and ten columns and staggered arrangement. In this experiment, heat and mass transfer coefficients and range are calculated with variations of cooling water and path. The results indicated that operating CWCT using two path have the high values of heat and mass transfer coefficients and range than one path.

• 한국농촌건축학회논문집
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• 제10권1호
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• pp.27-35
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• 2008

After researching 40 rural areas named 'valley' in Goesan County, Chungbuk Province, they are classified by 2 two classes. Firstly, villages located on the crossways valley are 22 of 40, they are located on the valley which is at right angles with a direction of light of a mountain range. A closed valley location is placed in the deep valley against a background mountain range. It is divided with closed large valley and small valley. Secondly, an open valley location style is 14 of 40. It means the villages are paralleled with a direction of mountain and located with same direction of entrance. This study is carried out to understand the characteristic of location in vernacular agricultural villages by judging from natural environment around the village. For this purpose, there were selected 3 villages of the valley categirized villages in Geosan Area which lean against valley. After classifying these sample by the morphorogical approach, according to compare them with pre-researched villages, the methodology of spatial structure was investigated in agriculture villages.

• Bulletin of the Korean Chemical Society
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• 제23권7호
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• pp.971-984
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• 2002

The multichannel quantum defect theory (MQDT) is reformulated into the form of the configuration mixing (CM) method using the geometrical construction of the S matrix developed for the system involving two open and one closed channels. The reformulation is done by the phase renormalization method of Giusti-Suzor and Fano. The rather unconventional short-range reactance matrix K whose diagonal elements are not zero is obtained though the Lu-Fano plot becomes symmetrical. The reformulation of MQDT yields the partial cross section formulas analogous to Fano's resonance formula, which has not easily been available in other's work.

• Nuclear Engineering and Technology
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• 제29권6호
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• pp.451-458
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• 1997

Signal shapes from a closed-ended coaxial HPGe detector are investigated by numerical methods. The detector used in this study has a volume of 72 ㎤ with relative efficiency of 15%. The electric field and potential distributions in the detector are determined by solving the Poisson equation at the depletion and operating bias. Hence the time dependent signal shapes induced on the electrode are obtained from the energy balance consideration and tv solving the equation of motion for the charge carriers. For various initial positions of a charge carrier pair, the collection times of induced charge vary in the range of 70 - 404 nsec.

• 한국공간구조학회논문집
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• 제20권2호
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• pp.69-76
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• 2020

Wind tunnel tests were conducted to analyze the wind fluctuating pressures on a circular closed and open dome roof with a low span rise. Two dome models with various geometric parameters (height/span ratios and open ratios) were used for fixed span rise ratio dome and wind pressure spectrum were analyzed. The applicability was examined in comparison with the spectral model proposed in the previous studies. The analysis results show that the wind pressure spectrum of open dome roof tends to increase power in the high frequency range and the second peak is found in the area different from the closed dome roof. In addition, according to the comparison analysis with the previous proposed spectral model, it was found that it is not applicable to the closed and open dome roofs with low rise ratio due to the different peak frequencies.

• Wind and Structures
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• 제25권4호
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• pp.397-413
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• 2017

When bridges are constructed with lower heights from the ground, the formed channel between the deck and the ground will inevitably hinder or accelerate the air flow. This in turn will have an impact on the aerodynamic forces on the deck, which may result in unexpected wind-induced responses of bridges. This phenomenon can be referred to "ground effects." So far, no systematic studies into ground effects on the wind-induced responses of closed box girders have been performed. In this paper, wind tunnel tests have been adopted to study the ground effects on the aerodynamic force coefficients and the wind-induced responses of a closed box girder. In correlation with the heights from the ground in two ground roughness, the aerodynamic force coefficients, the Strouhal number ($S_t$), the vortex-induced vibration (VIV) lock-in phenomena over a range of wind velocities, the VIV maximum amplitudes, the system torsional damping ratio, the flutter derivatives, the critical flutter wind speeds and their variation laws correlated with the heights from the ground of a closed box girder have been presented through wind tunnel tests. The outcomes show that the ground effects make the vortex-induced phenomena occur in advance and adversely affect the flutter stability.

• 한국농촌건축학회논문집
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• 제9권2호
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• pp.103-111
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• 2007

After researching 154 rural areas named 'valley' in Goesan County, Chungbuk Province, they are classified by 2 two classes. Firstly, villages located on the crossways valley are 109 of 154, they are located on the valley which is at right angles with a direction of light of a mountain range. A closed valley location is placed in the deep valley against a background mountain range. It is divided with closed large valley and small valley. Secondly, an open valley location style is 45 of 154. It means the villages are paralleled with a direction of mountain and located with same direction of entrance.