• Title/Summary/Keyword: processes optimization

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Formulation of Carbon Nanotube Paste and Its Optimization for Field Emission Display Applications

  • Kim, Yong-C.;Sohn, K.H.;Cho, Y.M.;Yoo, Eun-H.;Lee, Dong-Gu
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.696-699
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    • 2004
  • Of the emissive display technologies, field emission displays using pasted carbon nanotubes offer several advantages over other competing cathode materials such as low driving voltage, possible large-area and low-cost processes. In this study, formulation of carbon nanotube paste and its electron field emission properties are characterized. Also the effects of additive powders and surface morphology on electron emission are reported.

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Optimal Design of Fixture Layouts in Multi-Station Assembly Processes

  • Kim, Pan-Soo
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2006.11a
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    • pp.369-372
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    • 2006
  • Optimal engineering design is challenging because nonlinear objective functions need to be evaluated in a high-dimensional space. This paper presents a data-mining aided optimal design method. The method is employed in designing an optimal multi-station fixture layout. Its benefit is demonstrated by a comparison with currently available optimization methods.

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Tool life in Metal Forming Processes (소성가공에 있어서의 금형수명)

  • 최재찬;김병민
    • Transactions of Materials Processing
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    • v.3 no.2
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    • pp.147-155
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    • 1994
  • The service life of tools in metal forming technology is to a large extent limited by wear and fatigue fracture of the active elements. This presents a basic request for tool cost minimization and reduction of extensive machine down time, caused by premature tool failure. Currents developments are dominated by steps to reduce the causes of tool failure. A main problem of forming technology remains the insufficient reliability of tools due to a large and incalculable life time fluctuation. Only a systematic investigation of the failure mechanisms and operational loading of tools can lead to future improvements in tool layout, that is optimization of tool usage.

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A Study of Data Mining Optimization Model for the Credit Evaluation

  • Kim, Kap-Sik;Lee, Chang-Soon
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.4
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    • pp.825-836
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    • 2003
  • Based on customer information and financing processes in capital market, we derived individual models by applying multi-layered perceptrons, MDA, and decision tree. Further, the results from the existing single models were compared with the results from the integrated model that was developed using genetic algorithm. This study contributes not only to verifying the existing individual models and but also to overcoming the limitations of the existing approaches. We have depended upon the approaches that compare individual models and search for the best-fit model. However, this study presents a methodology to build an integrated data mining model using genetic algorithm.

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Plasmid Stabilitly of a Recombinant Escherichia coli and Optimization of Fermentation Processes (유전자 재조합 균주에서 플라스미드의 안정성과 발효 공정의 최적화)

  • 박성훈
    • Journal of Life Science
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    • v.2 no.1
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    • pp.26-34
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    • 1992
  • 유전자 재조합 균주의 발효에 있어서 플라스미드의 안정성과 발효공정의 최적화에 대해 개략적으로 서술하였다. 클론된 DNA의 발현은 플라스미드의 안정성을 크게 저해하며, 저하된 플라스미드의 안정성은 재조합 균주의 생산성을 많이 떨어뜨린다. 최적 발효 조건은 각각의 숙주-벡터 시스템, 사용한 배지, 생성물 등에 따라 크게 변한다. 동일한 숙주-벡터 시스템의 경우도, 사용하는 배지에 따라 온도, 희석률 또는 성장속도에 의존하는 정도가 달라지고 또 최적값도 다 변한다. 또한 발효조건의 최적화가 균체 내 플라스미드의 자기복제,mRNA로의 전사, 단백질로의 translation, 더 나아가 미생물 전체의 생리와 밀접하게 관련이 있다.

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Neural model predictive control for nonlinear chemical processes (비선형 화학공정의 신경망 모델예측제어)

  • 송정준;박선원
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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    • pp.490-495
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    • 1992
  • A neural model predictive control strategy combining a neural network for plant identification and a nonlinear programming algorithm for solving nonlinear control problems is proposed. A constrained nonlinear optimization approach using successive quadratic programming cooperates with neural identification network is used to generate the optimum control law for the complicate continuous/batch chemical reactor systems that have inherent nonlinear dynamics. Based on our approach, we developed a neural model predictive controller(NMPC) which shows excellent performances on nonlinear, model-plant mismatch cases of chemical reactor systems.

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Toxicokinetic Models and Data Interpretation (독성동태 모델과 데이터의 해석)

  • 유선동
    • Toxicological Research
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    • v.18 no.4
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    • pp.311-324
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    • 2002
  • Toxicokinetic studies are intended to provide critical evaluation of drug disposition at toxico-logical doses and help understand the relationship between blood or tissue levels and the time course of toxic events. Relatively high dose levels wed in toxicokinetics, compared to pharmacokinetics, complicates absorption, protein binding, metabolism and elimination processes. In this mini review, frequently wed toxicokinetic models such as linear compartment models, physiological models, and nonlinear kinetic mod-ec are introduced. In addition, optimization of toxicokinetic studies, their role in the drug development process, and prediction oj human toxicokinetics based on animal data by interspecies scaling are briefly discussed.

Estimation of Spatial Dependence with GEE

  • Lee, Yoon-Dong;Choi, Hye-Mi
    • Proceedings of the Korean Statistical Society Conference
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    • 2003.05a
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    • pp.269-273
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    • 2003
  • We consider an efficient parametric estimation method of spatial dependence in weak stationary processes. Spatial dependence is modeled through variogram and correlogram. Most of parametric estimation methods of correlogram use two step method; nonparametric estimation and parametric integration. We bind these two steps into one step by using GEE method instead of least squares type optimization. Our one step method is more efficient statistically and gives a clear interpretation of related concepts used in traditional two step methods.

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Outfitting and Painting Scheduling for Shipbuilding Using Constraint Satisfaction (제약 만족 기법을 이용한 기관의장과 선행도장의 일정계획)

  • Kim, Ki-Dong;Lee, Bo-Hurn
    • Journal of Industrial Technology
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    • v.26 no.A
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    • pp.173-180
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    • 2006
  • Scheduling for shipbuilding processes has many alternative solutions since it has long time horizon and handles many jobs. In this paper, an shipbuilding scheduling system for outfitting and painting is presented based on constraint satisfaction techniques(CST). We provide a field based model and an efficient solution methodology by using ILOG Scheduler and Solver. ILOG Solver support extensive optimization goals easily. We do verify the improvement and efficiency of the schedule generated by the scheduling system presented in this paper.

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Optimization of recombinant E. coli fermentation through biological manipulation and engineering control

  • Kim, Jeong-Yoon
    • The Microorganisms and Industry
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    • v.19 no.4
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    • pp.14-26
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    • 1993
  • Optimizing protein production in recombinant E. coli strains involves manipulation of genetic and environmental factors. In designing a production system, attention must be paid to gene expression efficiency, culture conditions and bioreactor configuration. Although not much emphasis was given to the physiology of host strains in this review, an understanding of the relationship between the physiology of host cell growth and the overproduction of a cloned gene protein is of primary importance to the improvement of the recombinant fermentation processes. Sometimes it is desirable to make use of gene fusion systems, e.g. protein A, polypeptide, gutathione-S-transferase, or pneumococcal murein hydrolase fusion, to facilitate protein purification.

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