• Title/Summary/Keyword: methodology

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A study on fault diagnosis of large chemical processes based on two-tier strategy (이단계 진단전략을 이용한 대형화학공정의 이상진단에 관한 연구)

  • 오영석;이병우;윤인섭
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1428-1431
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    • 1997
  • This paper presents an efficient fault diagnosis methodology for lare chemical processes. The methodology is based on a two-tier strategy, When a falt occurs in a process, a top tier identifies the sector (process part or unit) that may contain the fault(s). Afterwards, a bottom tier or lower level evaluates the suspicious sector. The process modeling methodology based on functionality-behavior relations of process units, is proposed and utilized in the top-tier. This methodology models a target process as sequences of functions and variables and their relations. In the bottom tier, each sector has a dedicated diagostic module, which is tailored to the available information or models of the sector. For the sectors selected in the top-tier diagnosis, each diagnostic module is executed to identify the actual faults within the sector. Teh utility of the methodology is illustrated in the diagnosis of the CSTR with heat exchanger.

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An Integrated Modeling Methodology on the CIMS for Ship Production (조선 CIMS에서의 통합 모형화 방법론)

  • Hwang, Sung-Ryoung;Kim, Jae-Gyun;Moon, Chi-Ung;Jang, Gil-Sang
    • IE interfaces
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    • v.13 no.1
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    • pp.65-77
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    • 2000
  • Nowadays, the modeling of systems have been enabled by various models and methodologies that are used for different purpose and perspectives upon the systems. The integrated modeling methodology that integrates these models and methodologies has become challenging issues in system integration such as CIM and PDM. The primary objective of this paper is to propose the comprehensive integrated modeling methodology that integrates the Extended IDEF0 function model, OOIDEF0 information model, navigation model, interface model, and organization model for an effective analysis and design of the CIMS for ship production. This methodology can be used for the integrated system, and cover the systems development life cycle in an integrated fashion. In order to prove the consistency and efficiency of the proposed methodology, the CIMS for ship production is modeled.

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Face Recognition Using A New Methodology For Independent Component Analysis (새로운 독립 요소 해석 방법론에 의한 얼굴 인식)

  • 류재흥;고재흥
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2000.11a
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    • pp.305-309
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    • 2000
  • In this paper, we presents a new methodology for face recognition after analysing conventional ICA(Independent Component Analysis) based approach. In the literature we found that ICA based methods have followed the same procedure without any exception, first PCA(Principal Component Analysis) has been used for feature extraction, next ICA learning method has been applied for feature enhancement in the reduced dimension. However, it is contradiction that features are extracted using higher order moments depend on variance, the second order statistics. It is not considered that a necessary component can be located in the discarded feature space. In the new methodology, features are extracted using the magnitude of kurtosis(4-th order central moment or cumulant). This corresponds to the PCA based feature extraction using eigenvalue(2nd order central moment or variance). The synergy effect of PCA and ICA can be achieved if PCA is used for noise reduction filter. ICA methodology is analysed using SVD(Singular Value Decomposition). PCA does whitening and noise reduction. ICA performs the feature extraction. Simulation results show the effectiveness of the methodology compared to the conventional ICA approach.

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Analysis of free surface motions in the hoot Pool of KALIMER (KALIMER 고온풀 자유액면 거동 해석)

  • Kim Seong-O;Eoh Jae-Hyuk;Choi Hoon-Ki
    • Journal of computational fluids engineering
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    • v.7 no.3
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    • pp.44-52
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    • 2002
  • An analytic methodology was developed for free surface motions between liquid metal coolant and cover gas in order to calculate the phenomena of gas entrainment in hot pool surface through IHX EMP and reactor core. The methodology was setup by applying the first order VOF convection model to CFX4 general purpose fluid dynamics analysis code. The methodology was validated by applying it to an experimental apparatus designed for free surface motions of KALIMER reactor. The distributions of free surface calculated by the present methodology were almost coincident with the experimental data. The developed methodology was applied to the KALIMER reactor of full power operating condition. The shapes of the free surface were nearly uniform. From the results, it was found that the altitude of the free surface from the IHX inlet nozzle of KALIMER reactor is high enough not to affect to free surface motions of generating gas bubbles from the turbulent shear flows such as hydraulic jump and water falls.

Development of a Practical Method to Optimize Two-Quality Characteristics in Injection Molded Parts (사출 성형품의 두 품질특성 최적화를 위한 실용적 방법의 개발)

  • Park, Jong-Cheon;Cha, Jae-Ho
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.6
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    • pp.90-97
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    • 2015
  • Optimization of multi-quality characteristics in injection molded parts is very important, but it is sometimes difficult for part/mold designers. The objective of this study is to develop a practical design methodology for optimizing two-quality characteristics of injection molded parts. To attain this end, we developed a new design-range reduction algorithm based on Taguchi's orthogonal arrays for two characteristics. Then, the algorithm was integrated with commercial injection-molding simulation tools. A feature of the proposed methodology is that it allows field-designers unfamiliar with general optimization methods to be able to apply the methodology to their design problems with ease. Finally, we have applied the proposed design methodology to optimization of weldlines and deflections in an actual bezel model. The results show the usefulness of this methodology.

Monitoring and Control of Turing Chatter using Sound Pressure and Stability Control Methodology (음압신호와 안정도제어법을 이용한 선삭작업에서의 채터 감시 및 제어)

  • 이성일
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.6 no.4
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    • pp.101-107
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    • 1997
  • In order to detect and suppress chatter in turning process, a stability control methodology was studied through manipulation of spindle speeds regarding to chatter frequencies, The chatter frequency was identified by monitoring and signal processing of sound pressure during turing on a lathe. The stability control methodology can select stable spindle speeds without knowing a prior knowledge of machine compliances and cutting dynamics. Reliability of the developed stability control methodology was verified through turing experiments on an engine lathe. Experimental results show that a microphone is an excellent sensor for chatter detection and control .

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A Hypermedia Design Methodology for the Knowledge Capitalization on Data Warehousing System

  • Kim, Jongho;Woojong Suh;Lee, Heeseok
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2001.01a
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    • pp.448-455
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    • 2001
  • Recently, many enterprises have attempted to capitalize knowledge assets on data warehouse (DW). It has been recognized as strategic core process to create corporate competitive advantage and implement enterprise e-biz strategies. However, most approaches to represent knowledge and decision process have limits in considering various knowledge types, their relationships and continuity in knowledge formulation. In addition, they are so inclined to one side such as concept-oriented frameworks or technology-oriented ones. They lack universal and wide-ranging features. This paper presents a comprehensive methodology to accumulate knowledge capital on DW via a properly grained hypermedia model. The methodology consists of three phases: knowledge requirement elicitation, hypermedia modeling, and system implementation. A real-life case for medical DW development is presented to demonstrate the usefulness of the proposed methodology. This methodology is effective when an organization accumulates knowledge assets to put the corporate e-biz or cre-biz strategy into practice.

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Development of Six Sigma Fit for Domestic Companies (한국적 6시그마 정착방향)

  • Lee, Pal-Hun
    • Journal of Korean Institute of Industrial Engineers
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    • v.32 no.4
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    • pp.268-278
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    • 2006
  • Ten years have passed since Samsung SDI and LG Electronics introduced six sigma. Six sigma spreads on the wide industry areas such as service and public sectors as well as manufacturing industry. Six sigma speaks for Korean enterprise's management innovation now. Then, can we evaluate that Korean enterprise's six sigma has settled down successfully? This study compares Korean enterprise's six sigma with those of Japanese and American enterprises in the view of leadership, project, people, and methodology. We suggest five topics for the successful settlement of six sigma in Korean enterprises; 1) Role of executives and managers should be changed more actively, 2) Strategy-connected projects should be excavated, 3) Utilization and development plan should be made for black belt and master black belt, 4) Six sigma methodology should be advanced, especially DFSS methodology, and finally 5) Several innovation methodology should be integrated.

A Study on the Validation Methodology of Network Analysis Applications in Energy Management Systems (계통운영시스템 계통해석 프로그램 검증 방안에 관한 연구)

  • Cho, Yoon-Sung
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.28 no.10
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    • pp.27-36
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    • 2014
  • Network analysis applications in energy management systems play a key role in the economic and reliable operation of power systems. In order to provide operators with useful network information, the accurate results of topology processing, state estimation, power flow, and contingency analysis must be simulated. This paper proposes a validation methodology of network analysis applications in energy management systems. The energy management systems was checked to ensure that it meets the originally specified functions based on the proposed methodology. In addition, the performance of state estimation is evaluated with the reference of the proposed methodology. The proposed methodology is being conducted by energy management systems and the Korean power systems have been utilized for the test systems.

Evaluation of seismic performance factors for steel DIAGRID structural system design

  • Lee, Dongkyu;Shin, Soomi;Ju, Youngkyu
    • Earthquakes and Structures
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    • v.10 no.4
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    • pp.735-755
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    • 2016
  • This article presents a proposed analytical methodology to determine seismic force-resisting system R-values for steel diagrid framed systems. As current model building codes do not explicitly address the seismic design performance factors for this new and emerging structural system, the purpose of this study is to provide a sound and reliable basis for defining such seismic design parameters. An approach and methodology for the reliable determination of seismic performance factors for use in the design of steel diagrid framed structural systems is proposed. The recommended methodology is based on current state-of-the-art and state-of-the practice methods including structural nonlinear dynamic analysis techniques, testing data requirements, building code design procedures and earthquake ground motion characterization. In determining appropriate seismic performance factors (R, ${\Omega}_O$, $C_d$) for new archetypical building structural systems, the methodology defines acceptably low values of probability against collapse under maximum considered earthquake ground shaking.