• Title/Summary/Keyword: Parameters Optimization

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Study for Development of the Fabrication System of Brain Model for Surgery Emulation (모의수술용 뇌모형 제작시스템 개발을 위한 연구)

  • 염상원;방재철;엄태준;주영철;김승우;공용해;천인국;김범태
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.298-298
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    • 2000
  • This paper presents the optimization technique to analyze the effect of the design parameters of rapid prototyping system for human brain model fabrication. The optimization method considers the functional relationships among the design parameters such as thickness gap, shrink rate, and laser speed that govern the operation of fabrication system. This paper applies a discrete optimization technique as the optimization method to determine the dominant parameter values. Additional study includes manner of complement surface image of ellipse which approximates the brain model using the adaptive slicing and the offset contour. According to the parameters tuning and interaction of effect, more suitable parameter values can be obtained by enhanced 3D brain model fabrication.

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Optimization of Incremental Sheet Forming Al5052 Using Response Surface Method (반응표면법을 이용한 Al5052 판재의 점진성형 최적화 연구)

  • Oh, S.H.;Xiao, X.;Kim, Y.S.
    • Transactions of Materials Processing
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    • v.30 no.1
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    • pp.27-34
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    • 2021
  • In this study, response surface method (RSM) was used in modeling and multi-objective optimization of the parameters of AA5052-H32 in incremental sheet forming (ISF). The goals of optimization were the maximum forming angle, minimum thickness reduction, and minimum surface roughness, with varying values in response to changes in production process parameters, such as tool diameter, tool spindle speed, step depth, and tool feed rate. A Box-Behnken experimental design (BBD) was used to develop an RSM model for modeling the variations in the forming angle, thickness reduction, and surface roughness in response to variations in process parameters. Subsequently, the RSM model was used as the fitness function for multi-objective optimization of the ISF process based on experimental design. The results showed that RSM can be effectively used to control the forming angle, thickness reduction, and surface roughness.

Optimization Method of Kalman Filter Parameters Based on Genetic Algorithm for Improvement of Indoor Positioning Accuracy of BLE Beacon (BLE Beacon의 실내 측위 정확도 향상을 위한 Genetic Algorithm 기반 Kalman Filter Parameters 최적화 방법)

  • Kim, Seong-Chang;Kim, Jin-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.11
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    • pp.1551-1558
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    • 2021
  • Beacon signals used in indoor positioning system are reflected and distorted, resulting in noise signals. KF(Kalman Filter) has been widely used to remove this noise. In order to apply the KF, optimization process considering the signal type, signal strength, and environmental elements of each product is required. In this paper, we propose a solution to the optimization problem of KF Parameters using GA(Genetic Algorithm) in BLE(Bluetooth Low Energy) Beacon-based indoor positioning system. After optimizing KF Parameters by applying the proposed technique with a certain distance between Beacon and receiver, we compared the estimated distance passed through KF with the unfiltered distance. The proposed technique is expected to reduce the time required and improve accuracy of KF Parameters optimization in an indoor positioning system based on RSSI (Received Signal Strength Indication).

Design optimization in hard turning of E19 alloy steel by analysing surface roughness, tool vibration and productivity

  • Azizi, Mohamed Walid;Keblouti, Ouahid;Boulanouar, Lakhdar;Yallese, Mohamed Athmane
    • Structural Engineering and Mechanics
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    • v.73 no.5
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    • pp.501-513
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    • 2020
  • In the present work, the optimization of machining parameters to achieve the desired technological parameters such as surface roughness, tool radial vibration and material removal rate have been carried out using response surface methodology (RSM). The hard turning of EN19 alloy steel with coated carbide (GC3015) cutting tools was studied. The main problem faced in manufacturer of hard and high precision components is the selection of optimum combination of cutting parameters for achieving required quality of surface finish with maximum production rate. This problem can be solved by development of mathematical model and execution of experiments by RSM. A face centred central composite design (FCCD), which comes under the RSM approach, with cutting parameters (cutting speed, feed rate and depth of cut) was used for statistical analysis. A second-order regression model were developed to correlate the cutting parameters with surface roughness, tool vibration and material removal rate. Consequently, numerical and graphical optimization were performed to obtain the most appropriate cutting parameters to produce the lowest surface roughness with minimal tool vibration and maximum material removal rate using desirability function approach. Finally, confirmation experiments were performed to verify the pertinence of the developed mathematical models.

Swarm Intelligence-based Optimal Design for Selecting the Kinematic Parameters of a Manipulator According to the Desired Task Space Trajectory (요청한 작업 경로에 따른 매니퓰레이터의 기구학적 변수 선정을 위한 군집 지능 기반 최적 설계)

  • Lee, Joonwoo
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.25 no.6
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    • pp.504-510
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    • 2016
  • Robots are widely utilized in many fields, and various demands need customized robots. This study proposes an optimal design method based on swarm intelligence for selecting the kinematic parameter of a manipulator according to the task space trajectory desired by the user. The optimal design method is dealt with herein as an optimization problem. This study is based on swarm intelligence-based optimization algorithms (i.e., ant colony optimization (ACO) and particle swarm optimization algorithms) to determine the optimal kinematic parameters of the manipulator. The former is used to select the optimal kinematic parameter values, whereas the latter is utilized to solve the inverse kinematic problem when the ACO determines the parameter values. This study solves a design problem with the PUMA 560 when the desired task space trajectory is given and discusses its results in the simulation part to verify the performance of the proposed design.

Design optimization of a nuclear main steam safety valve based on an E-AHF ensemble surrogate model

  • Chaoyong Zong;Maolin Shi;Qingye Li;Fuwen Liu;Weihao Zhou;Xueguan Song
    • Nuclear Engineering and Technology
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    • v.54 no.11
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    • pp.4181-4194
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    • 2022
  • Main steam safety valves are commonly used in nuclear power plants to provide final protections from overpressure events. Blowdown and dynamic stability are two critical characteristics of safety valves. However, due to the parameter sensitivity and multi-parameter features of safety valves, using traditional method to design and/or optimize them is generally difficult and/or inefficient. To overcome these problems, a surrogate model-based valve design optimization is carried out in this study, of particular interest are methods of valve surrogate modeling, valve parameters global sensitivity analysis and valve performance optimization. To construct the surrogate model, Design of Experiments (DoE) and Computational Fluid Dynamics (CFD) simulations of the safety valve were performed successively, thereby an ensemble surrogate model (E-AHF) was built for valve blowdown and stability predictions. With the developed E-AHF model, global sensitivity analysis (GSA) on the valve parameters was performed, thereby five primary parameters that affect valve performance were identified. Finally, the k-sigma method is used to conduct the robust optimization on the valve. After optimization, the valve remains stable, the minimum blowdown of the safety valve is reduced greatly from 13.30% to 2.70%, and the corresponding variance is reduced from 1.04 to 0.65 as well, confirming the feasibility and effectiveness of the optimization method proposed in this paper.

Wideband Gain Flattened Hybrid Erbium-doped Fiber Amplifier/Fiber Raman Amplifier

  • Afkhami, Hossein;Mowla, Alireza;Granpayeh, Nosrat;Hormozi, Azadeh Rastegari
    • Journal of the Optical Society of Korea
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    • v.14 no.4
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    • pp.342-350
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    • 2010
  • An optimal wideband gain flattened hybrid erbium-doped fiber amplifier/fiber Raman amplifier (EDFA/FRA) has been introduced. A new and effective optimization method called particle swarm optimization (PSO) is employed to find the optimized parameters of the EDFA/FRA. Numerous parameters which are the parameters of the erbium-doped fiber amplifier (EDFA) and the fiber Raman amplifier (FRA) define the gain spectrum of a hybrid EDFA/FRA. Here, we optimize the length, $Er^{3+}$ concentration, and pump power and wavelength of the EDFA and also pump powers and wavelengths of the FRA to obtain the flattest operating gain spectrum. Hybrid EDFA/FRA with 6-pumped- and 10-pumped-FRAs have been studied. Gain spectrum variations are 1.392 and 1.043 dB for the 6-pumped- and 10-pumped-FRAs, respectively, in the 108.5 km hybrid EDFA/FRAs, with 1 mW of input signal powers. Dense wavelength division multiplexing (DWDM) system with 60 signal channels in the wavelength range of 1529.2-1627.1 nm, i.e. the wide bandwidth of 98 nm, is studied. In this work, we have added FRA's pump wavelengths to the optimization parameters to obtain better results in comparison with the results presented in our previous works.

Estimation of Muscle-tendon Model Parameters Based on a Numeric Optimization (최적화기법에 의한 근육-건 모델 파라미터들의 추정)

  • Nam, Yoon-Su
    • Journal of the Korean Society for Precision Engineering
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    • v.26 no.6
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    • pp.122-130
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    • 2009
  • The analysis of human movement requires the knowledge of the Hill type muscle parameters, the muscle-tendon and moment arm length change as a function of joint angles. However, values of a subject's muscle parameters are very difficult to identify. It turns out from a sensitivity analysis that the tendon slack length and maximum muscle force are the two critical parameters among the Hill-type muscle model. Therefore, it could be claimed that the variation of the tendon slack length and maximum muscle force from the Delp's reference data will change the muscle characteristics of a subject remarkably. A numeric optimization method to search these tendon parameters specific to a subject is proposed, and the accuracy of the developed algorithm is evaluated through a numerical simulation.

Base Station Location Optimization in Mobile Communication System (이동 통신 시스템에서 기지국 위치의 최적화)

  • 변건식;이성신;장은영;오정근
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.14 no.5
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    • pp.499-505
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    • 2003
  • In the design of mobile wireless communication system, base station location is one of the most important parameters. Designing base station location, the cost must be minimized by combining various, complex parameters. We can solve this problem by combining optimization algorithm, such as Simulated Annealing, Tabu Search, Genetic Algorithm, Random Walk Algorithm that have been used extensively fur global optimization. This paper shows the 4 kinds of algorithm to be applied to the optimization of base station location for communication system and then compares, analyzes the results and shows optimization process of algorithm.

An Optimization Technique for Diesel Engine Combustion Using a Micro Genetic Algorithm (유전알고리즘을 이용한 디젤엔진의 연소최적화 기법에 대한 연구)

  • 김동광;조남효;차순창;조순호
    • Transactions of the Korean Society of Automotive Engineers
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    • v.12 no.3
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    • pp.51-58
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    • 2004
  • Optimization of engine desist and operation parameters using a genetic algorithm was demonstrated for direct injection diesel engine combustion. A micro genetic algorithm and a modified KIVA-3V code were used for the analysis and optimization of the engine combustion. At each generation of the optimization step the micro genetic algorithm generated five groups of parameter sets, and the five cases of KIVA-3V analysis were to be performed either in series or in parallel. The micro genetic algorithm code was also parallelized by using MPI programming, and a multi-CPU parallel supercomputer was used to speed up the optimization process by four times. An example case for a fixed engine speed was performed with six parameters of intake swirl ratio, compression ratio, fuel injection included angle, injector hole number, SOI, and injection duration. A simultaneous optimization technique for the whole range of engine speeds would be suggested for further studies.