• 제목/요약/키워드: End of primary

검색결과 749건 처리시간 0.033초

Detent Force Analysis in Permanent Magnet Linear Synchronous Motor Considering Longitudinal End Effects

  • Li, Liyi;Ma, Mingna;Chan, C.C.
    • Journal of international Conference on Electrical Machines and Systems
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    • 제2권1호
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    • pp.9-15
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    • 2013
  • This paper presents a uniform analytical model by energy method and Fourier series expansion to analyze detent force in uneven magnetic field for permanent magnet linear synchronous motor (PMLSM). The model reveals that detent force in long-primary type is mainly influenced by non-ideal distribution of permanent magnet magnetic motive force, while nounified air-gap permeance makes a great impact on detent force of short-primary type. Hence, magnetic field similarity of motor design techniques referring rotary counterpart are adopted. For long-primary type novel method of splitting edge magnets is proposed to reduce end effects force, and optimal widths of edge tooth in short-primary type also verify the effectiveness of magnetic field similarity. The experimental results validate finite element analysis results.

Thrust Performance Improvement of a Linear Induction Motor

  • Lee, Hyung-Woo;Park, Chan-Bae;Lee, Byung-Song
    • Journal of Electrical Engineering and Technology
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    • 제6권1호
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    • pp.81-85
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    • 2011
  • The end effect of a linear induction motor (LIM) has been known for several decades, especially in high speed operation. The exit part of the primary is not dealt as extensively as the entry part because of its minor effect. However, the exit part is one of the keys to weaken the dolphin effect, which occurs in high speed operation. In this paper, the concept of the virtual primary core is introduced, and chamfering of the primary outlet teeth is proposed to minimize the longitudinal end effect at the exit zone. For this, LIM for the high-speed train is designed and analyzed by using finite element method. Results confirm that chamfering can improve thrust performance effectively.

MRFR - Multipath-based Routing Protocol with Fast-Recovery of Failures on MANETs

  • Ngo, Hoai Phong;Kim, Myung Kyun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권2호
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    • pp.271-287
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    • 2013
  • We propose a new multipath-based reliable routing protocol on MANETs, Multipath-based Reliable routing protocol with Fast-Recovery of failures (MRFR). For reliable message transmission, MRFR tries to find the most reliable path between a source and a destination considering the end-to-end packet reception reliability of the routes. The established path consists of a primary path that is used to transmit messages, and the secondary paths that are used to recover the path when detecting failures on the primary path. After establishing the path, the source transmits messages through the primary path. If a node detects a link failure during message transmission, it can recover the path locally by switching from the primary to the secondary path. By allowing the intermediate nodes to locally recover the route failure, the proposed protocol can handle the dynamic topological change of the MANETs efficiently. The simulation result using the QualNet simulator shows that the MRFR protocol performs better than other protocols in terms of the end-to-end message delivery ratio and fault-tolerance capability.

MRFR - Multipath-based Routing Protocol with Fast-Recovery of Failures on MANETs

  • Ngo, Hoai Phong;Kim, Myung Kyun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제6권12호
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    • pp.3081-3099
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    • 2012
  • We propose a new multipath-based reliable routing protocol on MANETs, Multipath-based Reliable routing protocol with Fast-Recovery of failures (MRFR). For reliable message transmission, MRFR tries to find the most reliable path between a source and a destination considering the end-to-end packet reception reliability of the routes. The established path consists of a primary path that is used to transmit messages, and the secondary paths that are used to recover the path when detecting failures on the primary path. After establishing the path, the source transmits messages through the primary path. If a node detects a link failure during message transmission, it can recover the path locally by switching from the primary to the secondary path. By allowing the intermediate nodes to locally recover the route failure, the proposed protocol can handle the dynamic topological change of the MANETs efficiently. The simulation result using the QualNet simulator shows that the MRFR protocol performs better than other protocols in terms of the end-to-end message delivery ratio and fault-tolerance capability.

기관 절제 및 단단 문합술에 의한 기관 협착증의 치료 (Clinical Analysis of Cases of Segmental Resection and Primary Anastomosis in Tracheal Stenosis)

  • 신호승;김영민
    • 대한기관식도과학회지
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    • 제4권1호
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    • pp.27-34
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    • 1998
  • Despite improvement in respiratory care, including use of low pressure and high volume cuffed tubes, tracheal stenosis remains a serious complication after a long-term tracheal intubation and tracheostomy. In such patients, tracheal resection and primary anastomosis is still considered ideal therapeutic modality. Between 1989 and 1997, we performed tracheal resections with end-to-end anastomosis on 14 patients with no operative mortality and some morbidity. Tracheal stenosis was caused by tracheostomy in nine patients, by endotracheal intubation in three patients and by thyroid carcinoma in two patients. The length of stenosis was various from 2cm to 4.5cm. All patient underwent segmental tracheal resection and primary anastomosis(14 patients) and additional procedures were cricoid cartilage reconstruction(2 patients), suprahyoid laryngeal release(3patients), carinal release technique(2 patients) and arytenoidectomy(2 patients). We have nine complications: granulona at anastomosis site in four patients, vocal cord palsy in two patients and restenosis, pneumonia, skin necrosis in each of those patients. The granuloma was removed by bronchoscopic forceps(4 patients). Vocal cord palsy was treated by arytenoidectorny(2 patients), restenosis by T-tube insertion, pneumonia by antibiotics and skin necrosis was treated by skin graft. We reviews our expenence of clinical features of tracheal stenosis and surgical treatment by tracheal one-to-end anastomosis with additional procedures to avoid postoperative complications for sucessful results.

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MANET에서 백업경로를 이용한 빠른 경로복구 능력을 가진 라우팅 프로토콜 (A Routing Protocol with Fast-Recovery of Failures Using Backup Paths on MANETs)

  • 트란안타이;김명균
    • 한국정보통신학회논문지
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    • 제16권7호
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    • pp.1541-1548
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    • 2012
  • 본 논문에서는 MANET에서 링크고장 발생시 빠른 경로복구 기능을 갖는 다중경로기반 라우팅 프로토콜을 제안한다. 제안한 프로토콜은 데이터 전송이 필요할 경우 종단간 가장 신뢰성이 높은 주경로와 주경로상에 고장이 발생할 경우 전송경로를 복구하기 위한 보조경로를 설정하고, 주경로를 통해 데이터를 전송하게 된다. 데이터 전송도중 주경로상의 링크에 고장이 발생하면 보조경로를 이용하여 빠르게 복구함으로써 데이터의 손실을 줄이고 새로운 경로설정을 위한 제어패킷 트래픽을 줄이게 된다. 제안한 프로토콜의 성능을 QualNet 시뮬레이터를 이용하여 기존 프로토콜들과 비교분석하였고, 성능분석결과 본 논문에서 제안한 프로토콜이 기존 프로토콜들에 비해 종단간 패킷전송률이 약 10-20% 정도 높고, 링크고장시 경로복구시간은 3배 정도 빠름을 알 수 있었다.

표본건물 계측에 의한 공동주택 세대에서의 용도별 에너지사용량 및 CO2 배출량 연간 원단위 (2016 - 2017) 분석 (Annual Intensities (2016-2017) Analysis of Energy Use and CO2 Emission by End Use based on Measurements of Sample Apartment Units)

  • 진혜선;임한영;이수진;김성임;임재한;송승영
    • 대한건축학회논문집:구조계
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    • 제34권7호
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    • pp.43-52
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    • 2018
  • In this study, annual site and primary energy use intensities (EUIs) and CO2 emission intensities (CEIs) per area by end use were estimated based on the measurement data from June 2016 to May 2017 of 50 sample apartment units in Seoul. In addition, estimated site EUIs by end use were compared to the U.S. Residential Energy Consumption Survey (RECS) 2009 data. Site EUIs by end use were found to be in the order of heating > electric appliance > domestic hot water > cooking > lighting > cooling > air movement. In the case of primary EUIs and CEIs by end use, electric appliance was found to be the largest. As results of comparison with the RECS 2009 data, it was found that site EUIs were very similar for heating, domestic hot water and electric appliance, etc., but slightly different for cooling. The number of sample apartment units will continue to increase until 2020 (total number of samples 200) and intensities data by end use will be continuously updated through continuous collection of measurement data.

End-Effect Compensation in Linear Induction Motor Drives

  • Satvati, Mohammad Reza;Vaez-Zade, Sadegh
    • Journal of Power Electronics
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    • 제11권5호
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    • pp.697-703
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    • 2011
  • In this paper a control system with a high performance dynamic response for linear induction motors (LIMs) is proposed which takes into account the end-effect in both the machine model and the control system. Primary flux oriented control has two major drawbacks i.e. a lack of decoupling of the thrust and the flux and a possibility of system instability due to the end-effect. Both of these drawbacks have been dealt with in this paper. A flux estimation method is proposed to correct the flux orientation error caused by the end effect. Extensive motor performance evaluations under the proposed control system prove its superiority over conventional vector control.

Detection of Microphytobenthos Using Spectral Unmixing Method in the Saemangeum Tidal Flat, Korea

  • Lee, Y.K.;Won, J.S.;Ryu, J.H.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.853-855
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    • 2003
  • Microphytobenthos that supply nutrients to the intertidal ecosystem play an important part as a primary producer. If we estimate distribution and density of microphytobenthos, we can possibly calculate a volume of primary product in the tidal flat and its effect to the intertidal ecosystem. To estimate the portion of microphytobenthos, we used a linear spectral unmixing (LSU) method. LSU is a tool for inference the proportions of the pure components (or end-members) in a mixed pixel. The selection of end-members is critical to LSU. The end-members can be selected either from spectral libraries built from field surveys or from a remotely sensed image. We compared the two approaches of end-member selection, and the preliminary results showed end-members from from spectral library are as effective as those from image itself.

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45세 이상의 제 3형 견봉쇄골 관절 탈구 환자의 수술적 치료 - 일차적 쇄골 외측단 절제 술식과 고식적인 견봉쇄골 관절 정복 술식의 비교 - (The Surgical Treatment in Type III Acromioclavicular Dislocation Patients Over 45 Years - Primary Clavicular Lateral End Resection Method vs. Conventional Acromioclavicular Joint Reduction Method -)

  • 문은선;배봉현;최진;김명선
    • Clinics in Shoulder and Elbow
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    • 제8권2호
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    • pp.88-96
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    • 2005
  • Purpose: To compare and analyze the outcome of primary clavicular lateral end resection method and conventional acromioclavicular (AC) joint reduction method in type III AC dislocation patients over 45 years. Materials and Methods: This study was performed on selected 24 cases of type III AC dislocation patients, over 45 years of age, operated at our hospital from 1998 to 2002. Group I consist of 12 patients who underwent primary clavicular lateral end resection methods (average age: 54.3 years$(45{\sim}72)$). Group II consist of 7 patients using Bosworth methods and 5 patients using Phemister methods (average age: 54.4 years$(45{\sim}71)$). Clinical outcome was evaluated by Weaver and Dunn method. Radiological results were compared by measuring coracoclavicular distance between normal and injured side. Results: As clinical outcome, good was 10 cases(83%); fair 2(17%) in Group I, and good 6(50%); fair 3(25%); poor 3(25%) in Group II. In contrast, the difference of coracoclavicular distance was not statistically significant between two groups before or after surgery, and last follow up. At the last follow up, there was no special correlation between the difference of coracoclavicular distance and clinical outcome. Conclusion: We considered that primary clavicular lateral end resection may be effective for prevention of arthrosis in AC joint in type III AC dislocation patients over 45 years.