• 제목/요약/키워드: Performance engineering

검색결과 57,584건 처리시간 0.063초

On-line Fussy Performance Management of Profibus Networks

  • Lee, Kyung-Chang;Song Kang;Kim, Dong-Wook;Lee, Suk
    • International Journal of Precision Engineering and Manufacturing
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    • 제1권2호
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    • pp.5-13
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    • 2000
  • Most networks for automation are tuned to an expected traffic condition ar their design stage. During their actual operations, however, the networks experience considerable changes in traffic from time to time. These traffic changes caused by common events like machine failure and production schedule change may adversely affect th network performance and, in turn , the performance of the connected devices. This paper presents experimental results for performance management of a Profibus-FMS network. The performance management aims to maintain a uniform level of network performance at all stations under changing network traffic. The performance management algorithm monitors the performance of individual network stations and commands the stations to change their timer values in order to have comparable performance at all stations. In order to determine the amount of timer change, the algorithm employs a set of fuzzy rules. The algorithm has been evaluated on a Profibus network.

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접합부 회전성능에 따른 중간 철골 모멘트 골조의 내진 성능 평가 - I 성능평가 (Seismic Performance Evaluation According to Rotation Capacity of Connections for Intermediate Steel Moment Frames - I. Performance Evaluation)

  • 문기훈;한상환;하성진
    • 한국지진공학회논문집
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    • 제18권2호
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    • pp.95-103
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    • 2014
  • The current AISC341-10 standard specifiesa value of 0.02 radian for the minimum rotation capacity of connections for the intermediate steel moment frame system. However, despite of the advances realized in the domains of performance evaluation method and analysis method, research onthe minimum rotation capacity of the intermediate steel moment frame systemsatisfying the seismic performance has not been conducted in detail. In this study, the intermediate moment frame systemisdesigned with respect to current standards and the seismic performance in accordance with the rotational capacity of connections is evaluated using the seismic performance evaluation method presented in FEMA-P695. The minimum rotation capacity of intermediate steel moment frames required to satisfy seismic performance as well as the major design values affecting the seismic performance of moment frame areestimated. To that goal, the design parameters are selected and various target frames are designed. The analysis models of the main nonlinear elements are also developed for evaluating seismic performance. The resultsshow that the 20-story structure doesnot meet the seismic performance even if it satisfies the rotation capacity of 0.02 radian.

건설엔지니어링 기업의 경영성과측정모형 -H사의 사례를 중심으로- (A Management Performance Measurement Model of the Construction Engineering Firm -Focused on 'H' Construction Engineering Firm-)

  • 박찬식;김현준;전용석
    • 한국건설관리학회논문집
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    • 제5권2호
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    • pp.202-210
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    • 2004
  • 국내 엔지니어링 산업은 시장개방으로 인한 국제 경쟁력 확보, 선진국 대비 기술수준 낙후, 발주방식의 다양화 등으로 인하여 체계적인 사업전략의 수립 및 평가가 절실히 요구된다. 본 연구에서는 국내외 각 산업분야의 경영성과측정에 활용되고 있는 BSC를 건설엔지니어링 기업인 H사에 적용한 성과측정모형을 제시하였다. 성과측정모형은 기업의 중장기 발전계획, SWOT분석, 직원의식분석을 통하여 재무, 성장, 내부효율, 개선 및 학습의 4개의 관점으로 구성되며, 각각의 관점별로 핵심 성공요인과 주요성과지표를 도출하였다. 그리고 정렬분석과 일치분석을 통하여 성과측정모형의 유용성을 검증하였다.

성능이 서서히 저하되는 시스템의 신뢰도 척도 (Performance-Based Reliability Measures for Gracely Degrading Systems: the Concept)

  • Kim, Yon-Soo;Park, Sang-Min
    • 산업경영시스템학회지
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    • 제17권32호
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    • pp.227-232
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    • 1994
  • In the performance domain, physical performance is a measure that represents some degree of system, subsystem, component or device success in a continuous sense, as opposed to a classical binomial sense (success or failure). If applicable sensing and monitoring means exist, physical performance can be observed over time, along with explanatory variables or covariables. Performance-based reliability represents the probability that performance will remain satisfactory over a finite period of time or usage cycles in the future when a performance critical limit (which represents an appropriate definition of failure in terms of performance) is set at a fixed level, based on application requirements. In the case of inadequate knowledge of the failure mechanics, this physical based empirical modeling concept along with performance degradation knowledge can serve as an important analysis tool in reliability work in product and process improvement.

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중소제조기업에서 기술지향성이 경영성과에 미치는 영향에 관한 연구 (A Study on the Effects of Technology Orientation on the Enterprise Management Performance of Small and Medium-Sized Manufacturer)

  • 여형운;정영배
    • 산업경영시스템학회지
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    • 제37권4호
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    • pp.54-62
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    • 2014
  • This paper is present the Technology Orientation affects to Enterprise Management Performance. In order to carry out this research, we obtained 212 survey sheets and inspected ten assumptions based on the reliability, validity of the questionnaires. The results of regression analysis are summarized as follows; First, the factor of Technology Orientation, research development activity, affects to all factor of Enterprise Management Performance significantly. Second, the factor of Technology Orientation, research development environment, only effect on the technology performance. Third, research development ability is affect to technology performance and new product performance that factor of Enterprise Management Performance. Finally, technology industrialization ability isn't affects to Enterprise Management Performance significantly. Based on the results, we are recommendations for small and medium-sized manufacturing enterprises.

CMMI 기반의 무기체계 연구개발 프로세스 성과 모델 적용사례 연구 (A Case Study of CMMI-based R&D Process Performance Model for Weapon Systems)

  • 이혜진;장재덕;차승훈;최상욱;유제상
    • 시스템엔지니어링학술지
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    • 제16권1호
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    • pp.43-50
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    • 2020
  • Many companies around the world are applying CMMI to improve the organization's ability to perform projects, and many others are pushing to obtain CMMI certification as more and more of them are offered as preconditions for participation in projects or supply product. Organizations with high maturity such as CMMI Level 4~5, analyze the accumulated R&D data of the organization and establish the performance management model so that R&D performance is continuously managed. So this paper shows the R&D performance management model made by LIGNex1 which is certificated with CMMI Level 5 organization and the case applied to the project, including its effectiveness.

Seismic performance of RC columns with full resistance spot welding stirrups

  • Yu, Yunlong;Dang, Zhaohui;Yang, Yong;Chen, Yang;Li, Hui
    • Structural Engineering and Mechanics
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    • 제73권5호
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    • pp.543-554
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    • 2020
  • This paper aims to investigate the seismic performance of RC short columns and long columns with welding stirrups. Through the low-cyclic horizontal loading test of specimens, the seismic performance indexes such as failure modes, hysteretic curve, skeleton curve, ductility, energy dissipation capacity, stiffness degradation and strength degradation were emphatically analyzed. Furthermore, the effects of shear span ratio, stirrups ratio and axial compression ratio on the performance of specimens were studied. The results showed that the seismic performance of the RC short columns with welding stirrups were basically the same as that of the RC short columns with traditional stirrups, but the seismic performance of RC long columns with welding stirrups was better than that of RC long columns with traditional stirrups. The seismic performance of RC short columns and long columns with welding stirrups could be improved by increasing stirrup ratio and shear span ratio and reducing axial pressure ratio. Moreover, the welding stirrup have the advantages of steel saving, industrialization and standardization production, convenient construction, and reducing time, which indicated that the welding stirrups could be applied in practical engineering.

다층신경망을 이용한 드론 방제의 살포 균일도 예측 (Predicting the spray uniformity of pest control drone using multi-layer perceptron)

  • 성백겸;강승우;조수현;한웅철;유승화;이춘구;강영호;이대현
    • 드라이브 ㆍ 컨트롤
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    • 제20권3호
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    • pp.25-34
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    • 2023
  • In this study, we conducted a research on optimizing the spraying performance of agricultural drones and predicted the spraying performance in various flight conditions using the multi-layer perceptron (MLP). Data was collected using a test device for pesticide spraying performance according to the water sensitive paper (WSP) evaluation. MLP training involved supervised learning to achieve a coefficient of variation (CV), which indicates the degree of uniform spraying. The performance evaluation was conducted using R-squared (R2), the test samples showed an R2 of 0.80. The results of this study showed that drone spraying performance can be predicted under various flight environments. In addition, the correlation analysis between flight conditions and predicted spraying performance will be useful for further research on optimizing the spraying performance of agricultural drones.

A preliminary case study of resilience and performance of rehabilitated buildings subjected to earthquakes

  • Hadigheh, S. Ali;Mahini, S. Saeed;Setunge, Sujeeva;Mahin, Stephen A.
    • Earthquakes and Structures
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    • 제11권6호
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    • pp.967-982
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    • 2016
  • Current codes design the buildings based on life safety criteria. In a performance-based design (PBD) approach, decisions are made based on demands, such as target displacement and performance of structure in use. This type of design prevents loss of life but does not limit damages or maintain functionality. As a newly developed method, resilience-based design (RBD) aims to maintain functionality of buildings and provide liveable conditions after strong ground movement. In this paper, the seismic performance of plain and strengthened RC frames (an eight-story and two low-rise) is evaluated. In order to evaluate earthquake performance of the frames, the performance points of the frames are calculated by the capacity spectrum method (CSM) of ATC-40. This method estimates earthquake-induced deformation of an inelastic system using a reduced response spectrum. Finally, the seismic performances of the frames are evaluated and the results are compared with a resilience-based design criterion.

지반강성을 고려한 중저층 가새모멘트저항골조의 내진 목표성능평가 (Seismic Object Performance Evaluation of Braced Steel Moment Resisting Frames with Low Rise Building under Different Site Stiffness)

  • 김수정;최병정;박호영;이진우
    • 한국지진공학회논문집
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    • 제20권2호
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    • pp.91-101
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    • 2016
  • This study is the compared seismic performance that are difference between the performance of structures on various site classes and beam-column connection. this analysis model was designed the previous earthquake load. To compare the performance levels of the structure was subjected to nonlinear static and nonlinear dynamic analysis. Nonlinear analysis was used to The Perform 3D program. Nonlinear static analysis was compared with the performance point and Nonlinear dynamic analysis was compared the drift ratio(%). Analysis results, the soft site class of the displacement was more increase than rock site classes of the displacement. Also The smaller the displacement was increased beam-column connection stiffness.