• Title/Summary/Keyword: Optimal technology

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The Characteristics of Open-loop Trajectory and Time-to-go Estimation for Impact Angle Control Optimal Guidance through Inverse Optimal Problem (역최적 문제를 통한 충돌각 제어 최적유도법칙의 개루프 비행궤적 특성 및 Time-to-go 예측)

  • Lee, Yong-In;Lee, Jin-Ik
    • Journal of the Korea Institute of Military Science and Technology
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    • v.11 no.3
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    • pp.5-12
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    • 2008
  • This paper presents the features of an impact angle constrained open-loop optimal trajectory which is given by a function of initial conditions and optimal guidance gains. Using missile motion described by linearized kinematic equations and a proper form of performance index, an inverse optimal problem is suggested to investigate the gains related to the performance index. The flight trajectory and time-to-go can be shaped in terms of the optimal guidance gains. The results are evaluated by 3-DOF simulation.

Determination of Optimal Buffer Size for Semiconductor Production System using Harmony Search Algorithm (하모니서치 알고리즘을 이용한 반도체 공정의 최적버퍼 크기 결정)

  • Lee, Byeong-Gil;Byun, Minseok;Kim, Yeojin;Lee, Jonghwan
    • Journal of the Semiconductor & Display Technology
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    • v.19 no.4
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    • pp.39-45
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    • 2020
  • In the production process, the buffer acts as a buffer to alleviate some of the problems such as delays in delivery and process control failures in unexpected situations. Determining the optimal buffer size can contribute to system performance, such as increased output and resource utilization. However, there are difficulties in allocating the optimal buffer due to the complexity of the process or the increase in the number of variables. Therefore, the purpose of this research is proposing an optimal buffer allocation that maximizes throughput. First step is to design the production process to carry out the research. The second step is to maximize the throughput through the harmony search algorithm and to find the buffer capacity that minimizes the lead time. To verify the efficiency, comparing the ratio of the total increase in throughput to the total increase in buffer capacity.

Determining an Optimal Low Temperature Polycrystalline Silicon Crystallization Technology of LCD using Patent Map and AHP (특허맵과 AHP를 활용한 최적의 LCD 저온폴리실리콘 결정화 기술 선정)

  • KIM, Kwan Yeoul;Lee, Jang Hee
    • Knowledge Management Research
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    • v.12 no.1
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    • pp.39-52
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    • 2011
  • Many LCD manufacturers continue to develop the technologies of LCD manufacturing processes for the reduction of production cost, power consumption and high-resolution. The LTPS (Low Temperature Polycrystalline Silicon) crystallization technology is important for rearranging the internal structure of liquid crystal grain by adding certain energy to amorphous silicon and turning it into poly-silicon in order to manufacture LCD with better performance. We consider 14 existing technologies of LTPS crystallization in the LCD manufacturing and present an intelligent analysis methodology using patent map and AHP (Analytic Hierarchy Process) analysis for determining an optimal LTPS crystallization technology. By using patent map analysis, we easily understand the development process and mega-trend of LTPS crystallization technologies and their relationship. By using AHP analysis, we evaluate 14 LTPS technologies. Through the use of proposed methodology, we determine the Continuous Wave Laser Lateral Crystallization technology as an optimal one.

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Optimal Investment of Capacity and Production Planning of Flexible Manufacturing Technology Considering Economies of Scope (범위의 경제를 고려한 유연생산기술의 최적 용량투자 및 생산계획)

  • Lee, Deok-Joo
    • Journal of Korean Institute of Industrial Engineers
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    • v.31 no.2
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    • pp.135-142
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    • 2005
  • This study addresses the problem of flexible technology acquisition in a multi-product market when demands are uncertain. We confine the concept of flexibility to the ability of manufacturing system to produce a number of different types of products, called a product-mix flexibility type. And an analytical model in which the economies of scope are incorporated explicitly as a feature of flexible technology is presented to find the optimal investment decision to acquire flexible technology and optimal production planning. The characteristics of optimal investment strategy related to capacity and production planning are discussed.

Approximate Optimization Design Considering Automotive Wheel Stress (자동차용 휠의 응력을 고려한 근사 최적 설계)

  • Lee, Hyunseok;Lee, Jongsoo
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.24 no.3
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    • pp.302-307
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    • 2015
  • The automobile is an important means of transportation. For this reason, the automotive wheel is also an important component in the automotive industry because it acts as a load support and is closely related to safety. Thus, the wheel design is a very important safety aspect. In this paper, an optimal design for minimizing automotive wheel stress and increasing wheel safety is described. To study the optimal design, a central composite design (CCD) and D-optimal design theory are applied, and the approximate function using the response surface method (RSM) is generated. The optimal solutions using the non-dominant sorting genetic algorithm (NSGA-II) are then derived. Comparing CCD and D-optimal solution accuracy and verified the CCD can deduce more accuracy optimal solutions.

Design of the Optimal Controller for Takagi-Sugeno Fuzzy Systems and Its Application to Spacecraft control (Takagi-Sugeno 퍼지시스템에 대한 최적 제어기 설계 및 우주 비행체의 자세 제어 응용)

  • Park, Yeon-Muk;Tak, Min-Je
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.7
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    • pp.589-596
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    • 2001
  • In this paper, a new design methodology for the optimal control of nonlinear systems described by the TS(Takagi-Sugeno) fuzzy model is proposed. First, a new theorem concerning the optimal stabilizing control of a general nonlinear dynamic system is proposed. Next, based on the proposed theorem and the inverse optimal approach, an optimal controller synthesis procedure for a TS fuzzy system is given, Also, it is shown that the optimal controller can be found by solving a linear matrix inequality problem. Finally, the proposed method is applied to the attitude control of a rigid spacecraft to demonstrate its validity.

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Multiobjective Decision-Making applied to Ship Optimal Design

  • Wang, Li-Zheng;Xi, Rong-Fei;Bao, Cong-Xi
    • Journal of Ship and Ocean Technology
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    • v.5 no.1
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    • pp.30-37
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    • 2001
  • Ship optimal design is a multi-objective decision-making process and its optimal solution does not exit in general. It is a problem in which the decision-maker is very interested that an effective solution is how to be found which has good characteristic and is substituted for optimal solution in a sense. In the previous methods of multi-objective decision-making, the weighting coefficients are decided from the point of view of individuals which have a bit sub-jective an unilateral behavior. in order to fairly and objectively decide the weighting coeffi-cients, which are considered to be optimal in all system of multi-objective decision-making and satisfactory solution to the decision-maker, the pater presents a method of applying the Technology of the Biggest Entropy. It is proved that the method described in the paper is very feasible and effective be means of a practical example of ship optimal design.

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Optimal Time-Interval for Time-based Location Update in Mobile Communications

  • Lee, Goo-Yeon
    • Journal of Industrial Technology
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    • v.21 no.B
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    • pp.85-89
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    • 2001
  • In this paper, we analyze a time-based update method in location management and calculate the optimal time-interval. The probability that an MT is j rings away from the center cell is obtained by computer programming. And using these values, an exact analysis is made for the time-based location management cost. From the result, when the time-based method is applied to location update, we can get the optimal time-interval which minimizes the location management cost.

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An Application of Optimal Blank Design by Sensitivity Analysis to Stampings of General Shaped parts (민감도를 이용한 최적블랭크 설계법의 CAD 형식으로 표현된 금형에의 적용)

  • 손기찬
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.03a
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    • pp.45-48
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    • 1999
  • The optimal blank design method by sensitivity analysis has been applied to the formings of oil-pan, tailored blank and front panel have been chosen as the examples. Die shape is prepared by a commercial CAD system. Excellent results has been obtained between the numerical results and the target contour shapes. Through the investigation, the proposed systematic method of optimal blank design is found to be effective in the practical forming processes.

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Estimation of Optimal Operation Conditions in Step Feed Processes Based on Stoichiometric Nitrogen Removal Reactions

  • Lee, Byung-Dae
    • Journal of the Korean Applied Science and Technology
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    • v.28 no.1
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    • pp.6-9
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    • 2011
  • Step feed process was analyzed stoichiometrically for the optimal operation conditions in this study. In case of optimal operation conditions, minimum R (sludge recycling) value, r (internal recycling ratio) value, and n (influent allocation ratio) value for the step feed process to acquire the maximum TN removal efficiency were identified by theoretical analysis. Maximum TN removal efficiency, based on stoichiometric reaction, can be obtained by controlling n value for the step feed process.