• Title/Summary/Keyword: quality control method

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Comparison Study of Nonlinear CSAS Flight Control Law Design Using Dynamic Model Inversion and Classical Gain Scheduling (항공기 CSAS 설계를 위한 고전적 Gain Scheduling 기법과 Dynamic Model Inversion 비선형 기법의 비교 연구)

  • Ha, Cheol-Geun;Im, Sang-Su;Kim, Byeong-Su
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.7
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    • pp.574-581
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    • 2001
  • In this paper we design and evaluate the longitudinal nonlinear N(aub)z-CSAS(Command and Stability Augmentation System) flight control law in \"DMI(Dynamic Model Inversion)-method\" and classical \"Gain Scheduling-method\", respectively, to meet the handling quality requirements associated with push-over pull-up maneuver. It is told that the flight control law designed in \"DM-method\" is adequate to the full flight regime without gain scheduling and is efficient to produce the time response shape desired to the handling quality requirements. On the contrary, the flight control law designed in \"Gain Scheduling-method\" is easy to be implemented in flight control computer and insensitive to variation of the actuator model characteristics.n of the actuator model characteristics.

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A Study on the Urban Transit Vehicle Reliability Improvement Method using Quality Control Technique (품질관리기법을 이용한 도시철도차량 신뢰도 향상방안 연구)

  • Park, Kee-Jun
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.860-869
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    • 2011
  • It is very important that reduce the maintenance cost and extend life time of the urban transit EMU through effective maintenance method research. The maintenance cost of the urban transit EMU shares 60%~70% of it's life cycle cost. It means that the maintenance cost is bigger than the introduction cost of the urban transit EMU. In this study, I introduces a quality control technique to improve the urban transit vehicle reliability. I suggest the control chart using quality control technique. And the control charts apply to the Static Inverter of EMU.

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A Study on Establishment and Control of the Quality Control Policy (품질관리 방침의 설정과 관리에 관한 소고)

  • 이상억
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.8 no.11
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    • pp.35-43
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    • 1985
  • In this paper we will concentrate on the Quality Control Policy which should be enforced as a part of the Total Quality Control considers the global concepts, the establishment Procedures, and the evolution and operation of Quality control policy to achieve effectively it. For enforcement of the Qualify control policy shall be focused for considerations : (1) suggestion of the optimum control policy (2) suggestion of a comprehensive plan and promoting method quality control (3) suggestion of matters that need special consideration at the time of decision of a comprehensive management of control policy thereof. (4) A comprehensive Proposal (5) suggestion of a plan for progress of the Quality control system and the supplementary plan In the future, accordingly, establishment d its own policy control level is desirably more reasonable, and the Total Quality Control System that employes the control efficiency of periodical and systematic and rationalization and radical reform of the enterprise management problem as the restrictive conditions must be applied for quality control system.

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Response Calibration for Bridges based on Statistical Quality Control Chart (통계적 품질 관리도에 기초한 교량의 응답 보정)

  • Hwang, Jin Ha;An, Seoung Su;Kim, Ju Han
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.1
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    • pp.61-70
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    • 2013
  • This paper presents the response calibration method based on quality control range, which is established from the concept and method of statistical quality control for natural frequency ratio and response ratio. To this end, statistical analysis including descriptive statistics analysis, normality test, ANOVA were performed for response characteristics obtained from loading tests and structural analysis for more than hundred and thirty well-conditioned bridges. Suggested method is based on real structural integrity evaluation case studies and statistical quality control approach, in this respect it is expected to provide scientific criteria and systematic procedure for response calibration and load carrying capacity assessment.

A Study on the development quality control by application of QFD and Stage-gate in defense system (QFD 및 Stage-gate 모델을 활용한 국방분야 개발단계 품질관리 방안 연구)

  • Jang, Bong Ki
    • Journal of Korean Society for Quality Management
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    • v.42 no.3
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    • pp.279-290
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    • 2014
  • Purpose: The purpose of this study is to propose adoption of QFD and Stage-gate in order to analyze the quality of korea defense system. Methods: Drawing change data of initial production phase in korea defense system were anlayzed and a practical method was proposed. Results: The results of this study are as follows; Off line Quality Control should be introduced in development phase. Specially, in case of defense system, the best method is QFD(Quality Function Deployment) and Stage-gate process. At first, QFD 1 step defines product planning from VOC(Voice Of Customer), QFD 2 step specifies part planning from product planning, QFD 3 step defines process planning from part planning, QFD 4 step defines production planning from previous process planning. Secondly, Stage-gate process is adopted. This study is proposed 5 stage-gate in case of korea defense development. Gate 1 is located after SFR(System Function Review), Gate 2 is located after PDR(Preliminary Design Review), Gate 3 is located after CDR(Critical Design Review), Gate 4 is located after TRR(Test Readiness Review) and Gate 5 is located before specification documentation submission. Conclusion: Off line QC(Quality Control) in development phase is necessary prior to on line QC(Quality Control) in p roduction phase. For the purpose of off line quality control, QFD(Quality Function Deployment) and Stage-gate process can be adopted.

A study on improvement of policing perfomance by usage parameter control in asynchronous transfer mode networks (ATM망에서 사용자 변수 제어에 의한 감시 성능 개선에 관한 연구)

  • 한길성;오창석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.6
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    • pp.1480-1489
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    • 1996
  • In ATM networks there are two methods in traffic control as schemes advancing the quality of service. One is reactive control after congestion and the other which is generally recommended, is preventive control before congestion, including connection admission control on call leel and usage parameter control, network parameter control, priority control and congestion control on cell level. In particular, usage parameter control is required for restricting the peak cell rate of bursy tracffic to the parameter negotiated at call set-up phase since the peak cell rate significantly influences the network quality of service. The scheme for progressing quality of service by usage parameter control is themethod using VSA(Virtual Scheduling Algorlithm) recommended ITU-T. The method using VSSA(Virtual Scheduling Suggested Algorlithm) in this paper is suggested by considering cell delay variation and token rate of leaky bucket, compared VSA and VSANT(Virtual Scheduling Algolithm with No Tolerance) with VSSA which polices violated cell probability of conformed peak cell rate and intentionally excessive peak cell rate. VSSA method using IPP(Interruped Poisson Process) model of input traffic source showed more quality of service than VSA and VSANT methods as usage parameter control because the suggested method reduced the violated cell probability of contformed peak cell rate and intentionally excessive peak cell rate.

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Bootstrap control limits of process control charts for correlative process data

  • Suzuki Hideo
    • Proceedings of the Korean Society for Quality Management Conference
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    • 1998.11a
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    • pp.174-179
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    • 1998
  • This research explores the application of the bootstrap methods to the construction of control limits for the x charts and the EWMA charts based on single observations with stationary autoregressive processes. The subsample means-based control chars in the presence autocorrelation are also considered. We use a technique for inferring confidence intervals using bootstrap, the percentile method. Simulation studies are conducted to compare the performance of the bootstrap method and that of standard method for constructing control charts under several conditions.

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Short Run Production Cusum IX Chart & MR Chart (짧은 생산 주기를 갖는 누적합 개별치 관리도와 이동범위 관리도)

  • 신숙현;나인성;조남호
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.24 no.65
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    • pp.1-9
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    • 2001
  • Enterprises confronted the Environment of infinite competition should be prepared to abrupt variations of management environment and have the ability to be changed in short term. It has to be studied, the control method of products that correspond to molt-functionalization and reduced product life which is caused by high-quality and varied customers demands. As a process control method, we must be able not only to control varies characteristic in a control at once but also to detected special values quickly for high-quality. In this paper a control method referred above is presented.

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Markov Chain Method for Monitoring Several Correlated Quality Characteristics with Variable Sampling Intervals

  • Chang, Duk-Joon
    • Journal of Korean Society for Quality Management
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    • v.25 no.3
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    • pp.39-50
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    • 1997
  • Markov chain method to evaluate the properties of control charts with variable sampling intervals(VSI0 for simultaneously monitoring several correlated quality characteristics under multivariate normal process are investigated. For comparing the efficiencies and properties of multivariate control charts, we consider multivariate Shewhart, CUSUM and EWMA charts in terms of average time to signal(ATS) and average number of samples to signal(ANSS). We obtained stabilized numerical results with Markov chain method when the number of transient state is greater than 100.

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Picture Quality Control Method among Multiple Video Sources

  • Kwon, Soon-kak;Kim, Tae-suk
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2001.01a
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    • pp.316-321
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    • 2001
  • When the multiple video sources are together transmitted through the channel of fixed bandwidth, the efficiently picture quality method is necessary. This paper presents the picture quality control method to keep the same distortion level among the video sources. We first find a model of distortion and bitrate for the multiplexing system of multiple sources. Then we obtain the bitrate for each source to have same distortion level among the sources by using the approximated model parameters for simple implementation.

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