• 제목/요약/키워드: combination applications

검색결과 882건 처리시간 0.023초

인버터를 이용한 유도전동기 감속 성능 개선 (The Performance Improvement of stopping for Induction Motor Using AC Drive)

  • 박경훈;한경식
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2011년도 전력전자학술대회
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    • pp.296-297
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    • 2011
  • Many applications involving induction motors that are controlled using variable frequency drives require the ability to stop quickly. These applications include emergency stops, quick stopping of fans, centrifuges, presses, etc. The technique that is widely accepted in the industry for achieving quick stopping makes use of brake resistors in series with a power semiconductor switch. The switch-resistor combination (brake-unit) is applied across the dc bus. The fastest decelerating time achievable depends on the size of the resistors and the switch employed. In this paper, the authors propose a novel method of achieving quick stopping times without the use of any brake-unit. Experimental test results with and without this method on a large inertia motor-load combination show that the proposed stopping method is able to reduce the stopping time significantly compared to normal decelerated stop without the need for a braking unit.

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EDS(Event Driven Service) 시스템 구조에 관한 연구 (A Study on Architecture of Event Driven Service System)

  • 송광빈;조석팔
    • 정보학연구
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    • 제10권4호
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    • pp.11-26
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    • 2007
  • EDS is a typical convergence service performing convergence between functions owned by multiple SPs. EDS provides users with the relevant information and the communication by the various personal conditional environment. An alternative terminology for events for net- work related applications is 'triggers'-these are assumed to be included in the present description. Events could be defined as any activities which occur within a service avail ability, signals. Events can be managed, for example, as part of a context-aware application. EDS carry out a procedure for processing user's requested information about mobil network-based entities, such as the combination with various applications, such as a LBS (Location Based Service) and area information. In AS (Application Service) network environments, the user has his customized EDS in the network, the EDS automatically connects the appropriate Terminals consistent with a user profile. EDS can also send the collected information to other requesting users by way of event information and using the procedures of combination with other services. The user can record/retrieve the user-related information to from the information base through EDS.

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PZT-고분자 1-3-0형 복합압전체의 압전 및 음향특성 (Piezoelectric and Acoustic Properties of PZI-Polymer 1 -3-0 Type Composite)

  • 양윤석;유영준;최헌일;손무헌;사공건
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.317-320
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    • 1999
  • In this study, the piezoelectric ceramics PZT powder was synthesized by Wet-Dry combination method. And the flexible 1-3-0 type composites were fabricated with piezoceramic PZT and Eccogel polymer matrix embedded 3rd phase. Dielectric constant of 1-3-0 type composites was lower than that of single phase PZT ceramics. Thickness mode coupling factor k/sub t/ which was comparable with single phase PZT ceramics and mechanical quality factor Qm were about 0.65 and 6, respectively. These composites are considered as a good candidates for broad-band type transducer applications. The acoustic impedance of 1-3-0 type composites was lower than that of single phase PZT ceramics. Therefore, these composites would be better used for hydrophone applications.

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Design and Development of a Monitoring System based on Smart Device for Service Robot Applications

  • Lee, Jun;Seo, Yong-Ho
    • International Journal of Internet, Broadcasting and Communication
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    • 제10권3호
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    • pp.35-41
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    • 2018
  • Smart device has become an affordable main computing resource for robotic ap-plications in accordance with a fast growth of mobile internet environment. Since the computing power of smart device has been increased, smart device based ro-bot system attempts to replace traditional robot applications with laptop-based system. Methodologies for acquisition of remote sensory information and control of various types of robots using smart device have been proposed recently. In this paper, we propose a robot control system using a monitoring program and a communication protocol. The proposed system is a combination of an educa-tional programming oriented robot named EPOR-S. as small service robot plat-form and a smart device. Through a simulation study using image processing, the feasibility of combination of the proposed robot monitoring program and control system was verified.

효율성 제고를 위한 근사적 증거병합 방법 (An Approximate Evidence Combination Scheme for Increased Efficiency)

  • 이계성
    • 정보처리학회논문지B
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    • 제9B권1호
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    • pp.17-22
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    • 2002
  • Dempster-Shafer 증거병합 방법의 가장 큰 문제는 계산 복잡도가 지수적인 증가를 갖는다는 점이다. 이는 가설 집단을 이루는 원소의 개수가 각 가설을 이루는 속성 값들의 모든 부분 집합으로 focal 요소로 구성되기 때문이다. 이 문제를 피하기 위해 본 논문에서는 근사적 증거 병합 방법을 제안한다. 이 방법은 간단한 응용에 적용하여 그 성능을 조사하고 다른 증거 병합 방법의 하나인 VBS의 결과와 비교해 본다. 근사적 증거 병합방법은 계산 속도를 크게 개선하였고 전문가가 허용하는 편차 수준에서 신뢰 값을 갖는 것으로 평가되었다.

Periodic PM Policy for Repairable System with RCW or NCW

  • Jung, Gi-Mum;Kim, Dae-Kyung;Park, Dong-Ho
    • International Journal of Reliability and Applications
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    • 제3권3호
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    • pp.113-124
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    • 2002
  • This paper suggests the optimal periodic preventive maintenance policies after the combination warranty is expired. After the combination warranty is expired, a repairable system undergoes PM periodically and is minimally repaired at each failure. And also the system is replaced by a new system at the N th PM. In this case, we derive the mathematical formula for the expected cost rate per unit time. The optimal number and period for the periodic PM that minimize the expected cost rate per unit time are obtained. Some numerical examples are presented for illustrate purpose.

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On Convex Combination of Local Constant Regression

  • Mun, Jung-Won;Kim, Choong-Rak
    • Communications for Statistical Applications and Methods
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    • 제13권2호
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    • pp.379-387
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    • 2006
  • Local polynomial regression is widely used because of good properties such as such as the adaptation to various types of designs, the absence of boundary effects and minimax efficiency Choi and Hall (1998) proposed an estimator of regression function using a convex combination idea. They showed that a convex combination of three local linear estimators produces an estimator which has the same order of bias as a local cubic smoother. In this paper we suggest another estimator of regression function based on a convex combination of five local constant estimates. It turned out that this estimator has the same order of bias as a local cubic smoother.

Triple antibiotic paste: momentous roles and applications in endodontics: a review

  • Parhizkar, Ardavan;Nojehdehian, Hanieh;Asgary, Saeed
    • Restorative Dentistry and Endodontics
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    • 제43권3호
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    • pp.28.1-28.16
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    • 2018
  • This study investigated the latest findings and notions regarding 'triple antibiotic paste' (TAP) and its applications in dentistry, particularly endodontics. TAP is a combination of 3 antibiotics, ciprofloxacin, metronidazole, and minocycline. Despite the problems and pitfalls research pertaining to this paste has unveiled, it has been vastly used in endodontic treatments. The paste's applications vary, from vital pulp therapy to the recently introduced regeneration and revascularisation protocol. Studies have shown that the paste can eliminate the root canal microorganisms and prepare an appropriate matrix for further treatments. This combination is able to remove diverse groups of obligate and facultative gram-positive and gram-negative bacteria, providing an environment for healing. In regeneration protocol cases, this allows the development, disinfection, and possible sterilization of the root canal system, so that new tissue can infiltrate and grow into the radicular area. Moreover, TAP is capable of creating a discipline in which other wanted and needed treatments can be successfully performed. In conclusion, TAP, as an antibacterial intracanal medication, has diverse uses. Nevertheless, despite its positive effects, the paste has shown drawbacks. Further research concerning the combined paste and other intracanal medications to control microbiota is a must.

Structuring Element Representation of an Image and Its Applications

  • Oh, Jin-Sung
    • International Journal of Control, Automation, and Systems
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    • 제2권4호
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    • pp.509-515
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    • 2004
  • In this paper we present the linear combination of a fuzzy opening and closing filter with locally adaptive structuring elements that can preserve the geometrical features of an image. Based on the adaptation algorithm of linear combination of the fuzzy opening and closing filter, the optimal structuring element for image representation is obtained. The optimal structuring element is an indicator of the shape and direction of an object's image, which is useful in filtering, multi resolution, segmentation, and recognition of an image.

컴플렉스 브릿지 시스템의 신뢰도 분석 (Reliability Analysis of Complex Bridge System)

  • 최성운
    • 대한안전경영과학회지
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    • 제7권4호
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    • pp.219-227
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    • 2005
  • Three general algorithms for evaluating the reliability for complex bridge system are proposed. These methods, such as Keystone, Boolean, Network algorithms are powerful and effective to derive an reliability expression for many practical complex systems. The combination approach of RBD and FTA proposed in this paper provides an effective way to evaluate the functional dependency for applications of FMEA.