• 제목/요약/키워드: soft transfer

검색결과 292건 처리시간 0.025초

고성능 AC/AC 직접 전력변환을 위한 영 전압 스윗칭 싸이클로 콘버터 (Zero Voltage Switching Cycloconverter for High Performance Direct AC/AC Power Conversion)

  • 조정구;조규형
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1990년도 추계학술대회 논문집 학회본부
    • /
    • pp.272-277
    • /
    • 1990
  • A soft switched matrix converter is proposed by adopting the zero voltage switching technique being used in some resonant pole inverters. High operating frequency with safe and efficient switching improves dynamic and spectral performances and simplifies protection logics and snubber networks. Further, it can be implemented using simple analog circuits, having similar transfer characteristics to those of the modern pulse width modulated matrix converters such as, maximum voltage transfer ratio and unity input displacement factor. Analyses, design and simulation results are presented to verify the operating principle.

  • PDF

요족의 진단과 치료 (Diagnosis and Treatment of Cavus Foot)

  • 서재완;최우진;이진우
    • 대한족부족관절학회지
    • /
    • 제20권2호
    • /
    • pp.55-61
    • /
    • 2016
  • The cavus foot is a deformity characterized by an elevated medial longitudinal arch and a hindfoot varus with plantarflexed 1st ray. The etiology of cavus foot is usually related to neuromuscular disease or idiopathic cause. Thorough clinical and radiographic evaluation is required for differentiating etiology of the cavus. Most cases of cavus foot are stable and slowly progressive deformities which can initially be managed with conservative treatment including orthoses and physical therapies. Determining whether the deformity is flexible or rigid, the apex of the deformity and any muscle imbalances in foot and ankle is important for achievement of an adequately balanced plantigrade foot. Treatment should include systematic preoperative planning for selection of appropriate procedures for maintaining a functional and flexible foot with combinations of soft-tissue release, osteotomy, tendon transfer, and arthrodesis.

낮은 차원의 벡터 변환을 통한 음성 변환 (Voice conversion using low dimensional vector mapping)

  • 이기승;도원;윤대희
    • 전자공학회논문지S
    • /
    • 제35S권4호
    • /
    • pp.118-127
    • /
    • 1998
  • In this paper, we propose a voice personality transformation method which makes one person's voice sound like another person's voice. In order to transform the voice personality, vocal tract transfer function is used as a transformation parameter. Comparing with previous methods, the proposed method can obtain high-quality transformed speech with low computational complexity. Conversion between the vocal tract transfer functions is implemented by a linear mapping based on soft clustering. In this process, mean LPC cepstrum coefficients and mean removed LPC cepstrum modeled by the low dimensional vector are used as transformation parameters. To evaluate the performance of the proposed method, mapping rules are generated from 61 Korean words uttered by two male and one female speakers. These rules are then applied to 9 sentences uttered by the same persons, and objective evaluation and subjective listening tests for the transformed speech are performed.

  • PDF

후천적 성인 편평족 변형의 수술적 치료 (Operative Treatment of Acquired Adult Flatfoot)

  • 안치영;안재훈;김만수
    • 대한족부족관절학회지
    • /
    • 제18권3호
    • /
    • pp.93-99
    • /
    • 2014
  • Acquired adult flatfoot deformity is characterized by flattening of the medial longitudinal arch and dysfunction of the posteromedial soft tissues, including the posterior tibial tendon. When the non-operative treatment fails to result in improvement of symptoms, surgery should be considered. Operative techniques include flexor digitorum longus tendon transfer, calcaneal medial slide osteotomy, lateral column lengthening, and arthrodesis of the hindfoot. The principle of correcting the deformity while avoiding overcorrection and excessive stiffness is important in achievement of good outcomes in these patients.

Effects of radiation-modulated cooling on the momentum transfer from stellar feedback

  • Na, Chongsam;Kimm, Taysun
    • 천문학회보
    • /
    • 제44권1호
    • /
    • pp.70.2-70.2
    • /
    • 2019
  • Strong radiation fields can change the ionization state of metals and hence cooling rates. In order to understand their effects on the momentum transfer from radiation and supernova feedback, we perform a suite of radiation-hydrodynamic simulations with radiation-modulated metal cooling. For this purpose, we pre-tabulate the metal cooling rates for a variety of spectral shapes and flux levels with the spectral synthesis code, Cloudy, and accurately determine the rates based on the local radiation field strength. We find that the inclusion of the radiation-modulated metal cooling decreases the total radial momentum produced by photo-ionization heating by a factor of ~3 due to enhanced cooling at temperature T~10^3-4 K. The amount of momentum transferred from the subsequent SN explosions, however, turns out to be little affected by radiation, as the main cooling agents at T~10^5-6 K are only destroyed by soft X-ray radiation which is generally weak. We further discuss the total momentum budget in various conditions.

  • PDF

Dynamic Upper Eyelid Reconstruction for Total Periorbital Soft Tissue Loss

  • Vathulya, Madhubari;Manohar, Nishank;Jagtap, Manish Pradip;Mago, Vishal;Jayaprakash, Praveen A.
    • Archives of Plastic Surgery
    • /
    • 제49권3호
    • /
    • pp.319-323
    • /
    • 2022
  • Total eyelid defect comprises full-thickness loss of both upper and lower eyelids in a patient. It is a rare and devastating condition with serious implications related to vision, which mandates early and functional reconstruction when associated with intact globe. The primary goal is to give a stable coverage for orbital protection but at the same time provide a functional reconstruction of the defect, to allow for adequate mobility of the eyelids so that the patient's vision is restored to normal with minimal disability. When the defect is massive, and in the absence of loco-regional flaps, microvascular tissue transfer is needed. In this report we describe a radial-artery-based microvascular tissue transfer with a unique innovation utilizing the contralateral frontalis muscle to reconstruct a case of unilateral total upper and lower eyelid loss.

Seismic assessment of transfer plate high rise buildings

  • Su, R.K.L.;Chandler, A.M.;Li, J.H.;Lam, N.T.K.
    • Structural Engineering and Mechanics
    • /
    • 제14권3호
    • /
    • pp.287-306
    • /
    • 2002
  • The assessment of structural performance of transfer structures under potential seismic actions is presented. Various seismic assessment methodologies are used, with particular emphasis on the accurate modelling of the higher mode effects and the potential development of a soft storey effect in the mega-columns below the transfer plate (TP) level. Those methods include response spectrum analysis (RSA), manual calculation, pushover analysis (POA) and equivalent static load analysis (ESA). The capabilities and limitations of each method are highlighted. The paper aims, firstly, to determine the appropriate seismic assessment methodology for transfer structures using these different approaches, all of which can be undertaken with the resources generally available in a design office. Secondly, the paper highlights and discusses factors influencing the response behaviour of transfer structures, and finally provides a general indication of their seismic vulnerability. The representative Hong Kong building considered in this paper utilises a structural system with coupled shear walls and moment resisting portal-frames, above and below the TP, respectively. By adopting the wind load profile stipulated in the Code of Practice on Wind Effects: Hong Kong-1983, all the structural members are sized and detailed according to the British Standards BS8110 and the current local practices. The seismic displacement demand for the structure, when built on either rock or deep soil sites, was determined in a companion paper. The lateral load-displacement characteristic of the building, determined herein from manual calculation, has indicated that the poor ductility (brittle nature) of the mega-columns, due mainly to the high level of axial pre-compression as found from the analysis, cannot be effectively alleviated solely by increasing the quantity of confinement stirrups. The interstorey drift demands at lower and upper zones caused by seismic actions are found to be substantially higher than those arising from wind loads. The mega-columns supporting the TP and the coupling beams at higher zones are identified to be the most vulnerable components under seismic actions.

풍화된 암반에 근입된 현장타설말뚝의 하중전이 기구 (Load Transfer Mechanism of Drilled Shafts in Weathered Rock)

  • 권오성;조성민;정성준;김명모
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
    • /
    • pp.57-64
    • /
    • 2005
  • Since the allowable bearing capacities of piles in weathered/fractured rock are mainly governed by settlement, the load-displacement behavior of the rock socketed pile should be well known. To predict pile head settlement at the design stage, the exact understanding of the load-transfer mechanisms is essential. Therefore, in this research, the load-transfer mechanisms of drilled shaft socketed into weathered rock was investigated. For that, 5 cast-in-place concrete piles with diameters of 1,000 mm were socketed into weathered gneiss. The static axial load tests and the load-transfer measurements were performed to examine the axial resistant behavior of the piles. A comprehensive field/laboratory testing program on weathered rock at the field test sites was also performed to describe the in situ rock mass conditions quantitatively. And then, the effect of rock mass condition on the load transfer mechanism was investigated. The side shear resistance of the pile in moderately weathered rock reached to yielding point at a few millimeter displacements, and after that, the rate of resistance increment dramatically decreased. However, that in the highly /completely weathered rock did not show the obvious yielding point, and gradually increased showing the hyperbolic pattern until with the relatively high displacement (>10 mm). The end bearing-displacement curves showed linear increase at least until with the base displacement of approximately 10 mm, regardless rock mass conditions.

  • PDF

공학실무에서의 경계요소해석 소프트웨어 BEASY의 적용 (Application of The Boundary Element Analysis Software BEASY in Engineering Pratice)

  • 허영;조준상
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 1994년도 가을 학술발표회 논문집
    • /
    • pp.31-37
    • /
    • 1994
  • BEASY is a soft-ware tool which may be used to solve problems in heat transfer(linear and non-linear, steady state and transient) and linear elastic stress analysis. It is based on the boundary element method. The central part is the analysis module, called BEASY. For pre- and post-processing the BEASY Interactive Modeling System BEASY-IMS can be used. Three examples are devoted to show the capability of BEASY.

  • PDF