• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(5)
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• pp.153-156
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• 2002

The remotely operated underwater robotic vehicle system has been required to inspect some objects such as baffle former bolts and remove foreign objects in reactor vessel of nuclear power plant. In this paper, we have designed the remotely operated underwater robotic vehicle system that includes a long reach arm that is composed of 4 joints to remove foreign objects in a narrow space, a camera for visual test, instrument sensors for vehicle positioning, 4 thrusters for underwater navigation of vehicle, and supervisory control system implemented with industrial PC that includes robot simulator that has the functions of real time visualization, robot work planning and etc.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.449-450
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• 2015

최근 송전선로는 도시의 팽창과 지가하락 및 지역주민과의 많은 갈등으로 주로 산지에 송전선로가 설치되고 있는 추세에 있다, 이에 과거 20~30년 이전에 설치된 많은 송전선로 철탑은 이설 및 철거요구 민원이 끊임없이 제기되고 있으며, 또한 송전선로 주변에 농작물과 신규 건물 신축으로 송전선로와 전기적 이격거리 확보 문제가 계속 대두되고 있는 실정이다, 따라서 과거 기준에 의거 설치된 송전철탑의 전선로와의 이격거리 확보를 위해 지상고 상향 조정이 불가피하며 이를 해소하기 위해 기존 철탑을 철거하고 신규 철탑을 설치해야 하지만 용지확보 어려움과 지역주민과의 갈등으로 쉽지 않은 상황이다. 이에 보다 안정성, 시공성, 경제성을 고려한 새로운 공법 개발이 불가피한 실정으로 기존 임시철탑을 이용한 설치공법을 대체한 신공법을 개발하게 되었다.

• 융합신호처리학회논문지
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• 제2권2호
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• pp.89-94
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• 2001

본 논문에서는 로봇 매니플레이터의 고속 동작시 위치 제어의 정확성을 감소시키는 다중 모드 오차 진동을 제거 할 수 있는 단순한 슬라이딩 모드 제어를 소개한다. 또한 시스템의 파라메터 변화와 외란으로 인해 슬라이딩 평면 조건의 깨짐을 방지하기 위해 신경망 학습 기능이 사용되어 진다. 그러므로 본 논문에서는 신경망을 이용한 슬라이딩 모드 제어시스템이 설계되고, 제안된 제어 시스템의 성능은 시뮬레이션 을 통해 증명된다.

• 천문학회지
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• 제29권2호
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• pp.255-268
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• 1996

We present VR CCD photometry and long-slit spectroscopy of a late type spiral galaxy NGC 7678. The grey scale images and isophotal maps illustrate the presence of a weak bar from which spiral arms emerge. There are many HII regions along the spiral arms, but bright giant HII regions are more concentrated in the massive southern arm. The bright compact nucleus of NGC 7678 is bluer than bulge and bar. The spectral features of the nucleus and HII regoins are very similar but the nuclear spectra shows higher $[NII]{\lambda}6583/H_\alpha$ than those of the HII regions. The nucleus of NGC 7678 seems to be intermediate type between HII region nulcei and LINERs by the ratio of $[NII]{\lambda}6583/H_\alpha$, but it is more likely to be HII region-like nucleus if we consider the $[NII]{\lambda}6716,6731/H_\alpha$ together. The star formation rate is estimated to be about $0.2 M_\bigodot\;yr^{-1}$ based on the $H_\alpha$ flux.

• Journal of Species Research
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• 제9권3호
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• pp.273-279
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• 2020

We describe a newly recorded brittle star to South Korea, Amphiura (Amphiura) digitula (H.L. Clark, 1911), that was collected from Geoje Island, at a depth of 47 m. The species is characterized by a small disk, covered by numerous fine scales, small radial shields that are wider than long, a small stumpy hook at the distal end of the radial shield, two tooth papilla, two adoral shield spines, 2nd adoral shield spine longer than other, tapered dramatically toward dull tip, five arms with four proximal arm spines, and two tentacle scales. We also obtained a 657 bp sequence from COI gene and the amplified sequence matched the general DNA barcoding region. The NJ and ML phylogenetic analyses revealed A. (A.) digitula as monophyletic in the Amphiura clade. This species is clearly distinguished from other Amphiura species by morphological characteristics and the mitochondrial COI sequence, and thus represents the sixth Amphiura species reported to occur in Korea.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.1091-1098
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• 2003

Flexure bearings have been used in linear-resonant compressors to maintain a non-contacting clearance seal between the piston and cylinder. There are two types of tangential cantilever bearing and spiral arm bearing with flexure bearings. A newly devised linear flexure bearing (KIMM-Ml) for compression refrigeration machines is disclosed having improved tight gas clearance maintaining capability for better system performance. KIMM-Ml is an integrated device comprising an axially moving diaphragm with circumferentially arranged arc-shaped flexure blades secured between rim and hub spacers, which turn out to have higher radial stiffness than the one with circumferential tangential cantilever flexure blades. It is expected for KIMM-Ml to play a key role in designing long life, special purpose compression refrigeration machines by providing frictionless, non-wearing, linear movement and radial support for the machines as well as a gas clearance seal by maintaining extremely tight clearances between piston and cylinder.

• Journal of Plant Biology
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• 제19권2호
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• pp.33-36
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• 1976

Present work was attempted to investigate the karyotype, the reciprocal translocation of chromosomes and the geographical distribution of three Paeonia species grown wild in Korea with the aim of elucidating the taxonomical affinities of the species. Prior to conducting these works, it was required to clarify the karyotypes of the cultivated varieties of P. albiflora which has been grown since long time ago in this coundtry for medicinal value. Present report is part of the series of karyotype studies now being extensively conducted using varieties (or lines) of P. albiflora collected across the country. Arm ratio, number of trabant, kind of trabant chromosomes and karyotype formula are different among the six cultivated varieties. Excepting one, five varieties used had invariably trabants on D and E chromosomes while no trabant was found in C chromosome.

• 전기학회논문지
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• 제66권6호
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• pp.923-926
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• 2017

In this study, a novel wideband conformal thin antenna is presented for endoscopic capsule application at the 915 MHz Industrial, Scientific and Medical (ISM) band. The thickness of the antenna is only 0.2 mm which can be wrapped inside a capsule's inner wall. By cutting meandered slots on patch, open end slots on ground and utilizing long arm, the proposed antenna can obtain significant size reduction. The net volume of the proposed antenna including substrate and superstrate is only $37.4mm^3$ ($187mm^2$ surface area). This conformal antenna has shown good performance through simulation and measurement with maximum gain of -23 dBi and wide bandwidth from 137 MHz - 205 MHz depending on different environment. In addition, the effect of internal materials specially metallic battery is discussed briefly.

• 한국운동역학회지
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• 제17권3호
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• pp.225-232
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• 2007

This work intends to investigate the effects of shift characteristics on the propulsion performance of a manual wheelchair with an automatic transmission. A planetary gear train is employed to generate a two-stage shift automatically, based on the distance traveled from rest. Motion analysis has been performed for measuring kinematic properties of the arm and then the inverse dynamics has been applied for estimating joint forces/torques. Then, a parametric study has been performed to find a set of the shift ratios and the shift intervals for optimizing propulsion performance. Results show that the propulsion performance is closely related to the shift condition. It is found that a short shift interval is desirable for a short distance propulsion. However, an optimum shift interval for a long distance propulsion is inversely proportional to the shift ratio approximately. Consequently, the automatic transmission can greatly lower the joint loadings by the speed reduction, which eventually contribute to prevent joint injuries of wheelchair users.

• Journal of Chest Surgery
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• 제52권1호
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• pp.36-39
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• 2019

Primary malignant fibrous histiocytoma (MFH) of the chest wall is extremely rare and is characterized by aggressive features, including a high incidence of local recurrence and distant metastasis. Surgical resection of the chest wall is the primary modality of management. However, surgical treatment is not generally recommended in patients with evidence of distant metastasis. Here, we present a case of chest wall MFH along with a schwannoma mimicking distant metastasis in the right upper arm. The patient was treated by radical en bloc resection and survived for more than 9 years without recurrence.