• 제목/요약/키워드: saddle

검색결과 388건 처리시간 0.03초

1MVA Superconducting Generator Design (1MVA 급 초전도발전기 설계)

  • 백승규;손명환;권영길;류강식;조영식
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 한국초전도저온공학회 2000년도 KIASC Conference 2000 / 2000년도 학술대회 논문집
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    • pp.158-161
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    • 2000
  • Generally superconducting generators(S. G.'s) will be classified into 2 types according to their field coil shape. The first one is race-trace type and the other is saddle type. Race-track type S.G.'s have almost the same structure with conventional salient pole generators which are being used as largely small scale machines with more than 4 poles. On the other hand saddle type S.G.'s correspond to conventional cylindrical generators with 2 poles used for large turbines in power plants. In this paper 1MVA S.G. with saddle type field coil is electromagnetically designed and based on the research results from development of 30kVA S.G. with race-track type field oils in our group. other parts such as cooling systems and power leads are presented.

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A Study on Development of Power Transfer Capability Calculation Algorithm Considering the Closest Saddle Node Bifurcation for Voltage Stability (최단붕괴 전압안정도여유를 고려한 수송능력산정 알고리즘의 개발에 관한 연구)

  • 김용하;정현성;나인규;조성린;이재걸
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • 제52권10호
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    • pp.557-562
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    • 2003
  • This paper presents a power transfer capability calculation algorithm considering the closest saddle node bifurcation for voltage stability margin. In this method, voltage stability margin constraints considering the closest saddle node bifurcation are incorporated into a power transfer capability formulation to guarantee adequate voltage security levels in an interconnected power system. The proposed method is applied to IEEE-24 reliability test system and the results show the effectiveness of the method.

A Study on Development of Power Transfer Capability Calculation Algorithm Considering A Closest Saddle Node Bifurcation For Voltage Stability (최단전압붕괴점 전압안정도여유를 고려한 수송능력산정 알고리즘의 개발에 관한 연구)

  • Kim, Y.H.;Lee, Buhm;Choi, S.K.;Jung, H.S.;Lee, S.J.;Jo, S.R.
    • Proceedings of the KIEE Conference
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    • 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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    • pp.88-90
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    • 2002
  • This paper presents a power transfer capability calculation algorithm Considering A Closest Saddle Node Bifurcation For Voltage Stability Margin. In this method, voltage stability margin constraints considering a closest saddle node bifurcation are incorporated into a power transfer capability formulation to guarantee adequate voltage security levels in an interconnected Power System. The proposed method is applied to IEEE-24 Reliability Test System and the results shows the effectiveness of the method.

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Correlation between the subjective comfort and elastic body pressure distribution on a bicycle saddel (자전거 안장의 연체압 분포와 주관적 안락도의 상관성에 관한 연구)

  • 최정윤;박경수
    • Proceedings of the ESK Conference
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    • 대한인간공학회 1993년도 춘계학술대회논문집
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    • pp.145-145
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    • 1993
  • In bicycle design, saddle is the major part which effects the subjective comfort of rider. This study examines the correlation between the subjective comfort and elastic body pressure. The elastic body pressure measuring instrument for free-form surface such as saddle is developed by force sensor register, A/D converter and computer. The subjective comfort is measured quantit- atively by 11-point scale method and the elastic body pressure distribution is obtained through 3 different saddles at 4 postures. The pressure distribution is presented by computerized equi- pressure contour. While mean pressure, standard deviation of pressure, maximum pressure are inversely proportional to subjective comfort, the modified saddle-bearing weight which is the surface integral of pressure is directly proportional. Consequently, standard deviation of pressure is most important characteristic which affects variation of subjective comfort.

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Intersections of a Polyhedral Surface with Parallel Planes (다면체 곡면과 평행한 평면들과의 교선)

  • Jeon, Cha-Soo;Kim, Young-Yil
    • Journal of Korean Institute of Industrial Engineers
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    • 제21권4호
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    • pp.493-506
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    • 1995
  • Presented in this paper is an algorithm to obtain the intersections of a polyhedral surface composed of triangle facets with a series of parallel planes for extracting machining information from the surface. The change of the topology of the intersection curves is caused by characteristic points of the surface when sectioning the surface with parallel planes. The characteristic points are internal maximum, internal minimum, internal saddle, boundary maximum, boundary minimum, boundary max-saddle, and boundary min-saddle points. The starting points of the intersects are found efficiently and robustly using the characteristic points. The characteristic points as well as the intersection contours can be used to evaluate the machining information for process planning, and to generate NC tool path in CAD/CAM system.

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Reconstructive rhinoplasty with costal cartilage grafting: A case report of relapsing polychondritis

  • Lee, Yunhae;Choi, Hyungon
    • Archives of Craniofacial Surgery
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    • 제20권5호
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    • pp.341-344
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    • 2019
  • Relapsing polychondritis (RP) is a rare autoimmune disorder of unknown etiology characterized by recurrent episodes of inflammation and the destruction of cartilaginous tissues, primarily involving the ear, nose, and the respiratory tract. Nasal chondritis is present in 24% of patients at the time of diagnosis and develops subsequently in 53% throughout the diseases progress. Progressive destruction of nasal cartilage leads to the characteristic flattening of the nasal bridge, resulting in the saddle nose deformity. In patients with RP, surgical management for saddle nose is carefully decided due to the disease relapsing characteristics. We present a RP patient with a saddle nose deformity who underwent reconstruction rhinoplasty with autologous costal cartilage grafting. At 6-month follow-up, the patient retained good esthetic results and showed neither complication nor relapse of RP.

Saddle Embolism Caused by Left Atrial Myxoma -A Case Report- (안장 색전증을 유발한 좌심방 점액종 -수술 치험 1례-)

  • 송정근
    • Journal of Chest Surgery
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    • 제28권3호
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    • pp.316-319
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    • 1995
  • Systemic emboli occur in approximately one-third of patients with cardiac myxoma. Embolization is common because of the friability of the tumor and intracardiac location. Embolic episodes in young patients with normal sinus rhythm should arouse suspicions of cardiac myxoma in the absence of active endocarditis. We present one case of 17 years old girl having saddle embolism combined with left atrial myxoma. We planned staged operation. First, the emergency thromboembolectomy of aortic bifurcation was performed through bilateral transfemoral approach with use of Forgaty catheter. One week later, the extirpation of myxoma was successfully done with ECC.

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MULTIOBJECTIVE FRACTIONAL PROGRAMMING WITH A MODIFIED OBJECTIVE FUNCTION

  • Kim, Do-Sang
    • Communications of the Korean Mathematical Society
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    • 제20권4호
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    • pp.837-847
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    • 2005
  • We consider multiobjective fractional programming problems with generalized invexity. An equivalent multiobjective programming problem is formulated by using a modification of the objective function due to Antczak. We give relations between a multiobjective fractional programming problem and an equivalent multiobjective fractional problem which has a modified objective function. And we present modified vector saddle point theorems.