• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 추계학술대회 논문집
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• pp.123-124
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• 2014

본 논문에서 제안하는 Asymmetric 암 구조를 가지는 단상 멀티레벨 인버터는 양방향 스위치를 사용하여 (4m-2)개의 스위치로 n-레벨의 출력 전압을 생성한다. m은 A 암의 전압원수이다. 본 토폴로지는 A 암과 B 암을 형성하는 각각의 커패시터 전압원의 수가 동일하지 않는 것이 특징이다. 이러한 비대칭 전압원 구조의 조합으로 출력 전압 레벨 수를 최대화한다. 제안된 Asymmetric 암 구조를 가지는 단상 멀티레벨 토폴로지는 PSIM 시뮬레이터를 통해 11-레벨로 구현하여 타당성을 검증하였다.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1381-1384
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• 2005

Surface modification of tridimensional cubic mesoporous silica, SBA-16, was investigated with pendant arm functionalized cobalt diaminosarcophagine (diAMsar) cage complex which covalently grafted onto the silica surface through the silication with sylanol group. The spectroscopic results showed that the mesoporous structure was preserved under the $[Co(diAMsar)]^{3+}$ grafting reaction condition. Successful grafting prevented the cobalt diAMsar cage from leaching out from the SBA-16 support.

• 천문학회지
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• 제33권3호
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• pp.151-158
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• 2000

We conducted a deep CCD observations in V band to obtain stellar density distribution and to determine the distances toward two molecular clouds with anomalous velocity in the Galactic anti-center region. Star count method based on the linear programming technique was applied to the CCD photometric data. We found two prominent peaks at distances of around 1.4 and 2.7 kpc. It is found that the first peak coincides well with stellar density enhancement of B8-A0 stars and the second one with the outer Perseus arm. The effect of the choice of the luminosity function is discussed. The stellar number density distribution is used to derive the distances to the molecular clouds and the visual extinctions caused by the clouds. We found that two molecular clouds are located almost at the same distance of about 1.1 $\pm$ 0.1 kpc, and the peak extinctions caused by the clouds are about 2.2 $\pm$ 0.3 mag in V band.

• 천문학회지
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• 제23권2호
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• pp.85-96
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• 1990

High resolution $^{12}CO$ observations of the region containing the planetary nebula Hb12 were made with the Nobeyama Radio Telescope. These observations reveal that there is no significant CO emission from Hb 12 itself. Near Hb 12, however, the observed regions show a structure of clustered dark clouds whose physical parameters suggest that these clumps would be further fragmented or collapesed. Also found with the high resolution observations is that a few isolated clumps are located away from the main CO feature extended possibly from the galactic plane. For more detail morphologies and velocity structures of the clumps, especially in relation to the large CO complex to which these are likely to be associated, more observations are substantiated.

• 한국주조공학회지
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• 제32권5호
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• pp.225-230
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• 2012

In this study, a more practical and simulation approach which can predict the mechanical properties of aluminum alloys is proposed. First, cooling rate, micro-structure, and mechanical properties of casting product were measured through casting experiment. The relation between cooling rate and SDAS decrease exponentially and the linearly decreasing relation exist between SDAS and mechanical properties. Then, the cooling rate was calculated by casting process simulation and the mechanical properties were predicted by using the relations that were derived through experiment. Experimentally measured mechanical properties and predicted values by simulation were in the range of relatively small difference. The mechanical properties of various Al alloys are expected to be predicted by the casting process simulation before actual casting.

• Clinical and Experimental Pediatrics
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• 제49권8호
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• pp.821-829
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• 2006

Hemophilia is the most common coagulation disorder. It has a long history. Hemophilia A is caused by FVIII gene mutation, and hemophilia B by FIX gene mutation. Those genes are located on X chromosome long arm. Bleedings in hemophiliacs predominantly occur in joints and muscles. Because those site are insufficient in tissue factor to induce hemostasis. Among joints knee, ankle and elbow are most frequently affected because their synovial structure is vulnerable to injury compared to other joints. Hemophilia is diagnosed with factor assay. Severe hemophilia is below 1% of FVIII : C, moderate between 1% and 5%, mild over 5%. Carrier detection and prenatal diagnosis have been conducted with RFLP-based linkage analysis and DNA sequencing. Mainstay of treatment is factor replacement therapy so far. Bleedings can be controlled by infusion of factor concentrates. Hemophilc arthropathy and muscle contracture are representative sequelae. Complications of facotor replacement therapy are inhibitor development and infections. Hemophiliacs with inhibitor should be managed with large dose factor concentrate, bypassing agent, ITI and immunosuppression. Ultimately, hemophilia could be cured by gene therapy.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.664-669
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• 2003

This paper proposes a swing-arm type dual-stage actuator, which consists of a PZT actuator for fine motion and a VCM(Voice Coil Motor) for coarse motion, for SFF ODD(Small Form Factor Optical Disk Drive), in order to achieve fast access speed and precise track following control. We focus our attention on the design and control of the PZT actuator, because there have been a lot of previous researches related to the VCM and dual-stage actuators. Due to the dual cantilever structure, the PZT actuator can generate precise translational tracking motion at its tip where optical pickup is attached at, and the effect of hysteric behavior of the PZT element is reduced. The dynamic model of the PZT actuator is derived by using the Hamilton's principle, and verified by comparing with the experimental frequency response. The sliding mode control is designed in order to be robust against modeling uncertainties. Simulations and experimental results confirm the effectiveness of the suggested control scheme.

• 제어로봇시스템학회논문지
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• 제13권7호
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• pp.671-676
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• 2007

In this paper, a novel neuro-fuzzy controller is presented. The generic fuzzy controller is compensated by a neural network controller so that an overall control structure forms a neuro-fuzzy controller. The proposed neuro-fuzzy controller solves the difficulty of selecting optimal fuzzy rules by providing the similar effect of modifying fuzzy rules simply by changing crisp input values. The performance of the proposed controller is tested by controlling humanoid robot arms. The humanoid robot arm is analyzed and implemented. Experimental studies have shown that the performance of the proposed controller is better than that of a PID controller and of a generic fuzzy PD controller.

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2701-2704
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• 2010

This work shows that both L2 and L3 bearing two and four N-$(CH_2)_2OCH_3$ groups, respectively, can be prepared selectively by the reaction of $L^1$ with 1-bromo-2-methoxyethane. The di-N-substituted macrocycle $L^2$ readily forms its copper(II) and nickel(II) complexes. The N-$(CH_2)_2OCH_3$ groups in $[CuL^2]^{2+}$ are coordinated to the metal ion, whereas those in $[NiL^2]^{2+}$ are not involved in coordination. Interestingly, $L^3$ reacts with $Cu^{2+}$ ion to form $[Cu(HL^3)]^{3+}$, in which one tertiary amino group is not involved in coordination.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2467-2470
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• 2003

This paper presents a new structure of MPEG-4 AAC encoder. The proposed encoder directly shapes quantization noise distribution according to the energy distribution curve and thereafter performs adjustment of the offset level of the noise distribution to meet the given bit rate. The direct noise shaping and the bit rate matching scheme of the proposed encoder algorithm significantly alleviate the problem of conventional encoder's processing burden related with the employment of the precise psychoacoustic model and iteration intensive quantizer. The encoder algorithm is implemented on ARM processor with fixed-feint arithmetic operations. The audio quality of the implemented system is observed comparable to those of commercially available encoders, white the complexity of the implementation is drastically reduced in comparison to the conventional encoder systems.