• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.883-888
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• 2008

Various effluents generated in cooking processes contribute a great deal to indoor air pollution among many other indoor pollutants such as dusts from outdoor and carbon dioxide from human body. Kitchen exhaust hoods are not believed to exhaust indoor contaminants properly in many cases, while generating too much noise. Instead of focusing on individual products of kitchen hoods, we should address the problem by attacking the ventilation system as a whole including vertical shafts and building air-tightness. In this study, it is intended to investigate the pressure distribution along the vertical shaft depending on various system parameters, such as shaft size, concurrent hood usage rate, roof fan, inlet pressure loss, and outdoor temperature. The maximum static pressure in the vertical shaft has been obtained using the method of design of experiments and analyzed by the analysis of variance. The results can be used for the design of kitchen exhaust systems by analyzing the pressure distributions in vertical shafts.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.8
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• pp.104-111
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• 2009

In this paper, the gear design program is presented. The profile of gears is created using classical mathematic formulations. In each gear, a kinematic joint is applied and one can define the 20 contact condition between gear pairs. Initial and boundary conditions such as force, torque, velocity, acceleration, etc. can be set. Thus, it is possible to analyze dynamic characteristics of gear pairs such as reaction moment and the variation of angular velocity. In order to find the optimal profile of gear pairs, two optimization methods based on design of experiments are inserted in the program; One is the Taguchi method and the other is the response surface analysis method. To verify the program, the rack & pinion gear is created and analyzed. Simulation results show that the developed program is useful and result data is reliable.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.5
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• pp.860-868
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• 2007

In this paper. design of spoke type BLDC motor which have a characteristics of concentrating fluxes and relatively high reluctance torque among IPM BLDC motors has been researched. To reduce cogging torque and torque ripple. rotor pole shape of optimal design is proposed. To clearly see the effects due to the changed rotor pole shape. magnetic circuit model. 2D FEM and design of experiments (DOE) are used. Then considering these results proper rotor pole shape which have an good effect on air gap flux density and cogging torque. back-emf is designed. Moreover. the validity of proposed model in this paper is also verified by comparison between gained experiment and analysis data.

• Journal of Power System Engineering
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• v.15 no.5
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• pp.72-76
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• 2011

In this work, the parameter optimization for thermal-sprayed Al/SiC composites have been designed by $L_9(3^4)$ orthogonal array and analysis of variance(ANOVA). Al/SiC composites were fabricated by flame spray process on steel substrate. The hardness of composites were measured using micro-vickers hardness tester, and these results were analyzed by ANOVA. The ANOVA results showed that the oxygen gas flow, powder feed rate and spray distance affect on the hardness of the Al/SiC composites. From the ANOVA results, the optimal combination of the flame spray parameters could be extracted. It was considered that experimental design using orthogonal array and ANOVA was efficient to determine optimal parameter of thermal-sprayed Al/SiC composites.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1414-1417
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• 2003

In chemical forming process, mixed materials of LDPE, EVA and forming agent are used. However mechanical properties has been dropping remarkably through this forming process. In this study, Above materials(LDPE, EVA) were used in microcellular foaming injection process. And various effective factors in this process were selected by Axiomatic approach and systematically estimated by DOE(Design of Experiments). As a results, injection type and rate of mixing resins have more influence on forming rate than other factors.

• Journal of the Korean Data and Information Science Society
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• v.17 no.4
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• pp.1299-1307
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• 2006

This study investigates solving production problems in an automotive stamping plant using Finite Element (FE) analysis. The fundamentals of stamping, metal plasticity and FE analysis are developed. In this paper, we provide the basis for a simulation of the stamping of a production part, the automotive rear floorpan. On-plant factorial Design of Experiments (DoE) were simulated using the floorpan model. The accuracy of the simulations was undetermined because of variability in the DoE results. Predictions of flange shape, wrinkling and thickness show qualitative agreement with manufactured parts and indicate that simulating an industrial part is feasible.

• Journal of the Korean Data and Information Science Society
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• v.17 no.2
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• pp.633-645
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• 2006

The sheet metal stamping process continues to be a challenge to the field of science and engineering. The focus of this paper is to gain a better understanding of the sheet metal stamping process. By using Finite Element analysis and Design of Experiments, we are trying to analyze the stamping variables and determine which ones influence the stamping operations most.

• Tribology and Lubricants
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• v.36 no.4
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• pp.215-231
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• 2020

The paper presents extensive survey and review of experimental and analytical researches on fluid film bearings and squeeze film dampers (SFDs) for turbomachinery available in open literature (major archival international journals) published recently (2018 and 2019 only). Over 60 published research works are reviewed based on the research topics and objectives, the types of bearings, size of bearings, and main design parameters with a brief summary of experiments and/or predictions in each work. Some important findings and general observations about the experimental and/or predictive data are also presented. There are several major trends observed throughout the survey. A large portion of the papers focuses on bearing surface textures and effect of operating and assembly conditions on static and/or dynamic forced performances, as well as bearing surface roughness and wear patterns. Researches on geometry of orifices and recesses in hydrostatic (or hybrid) bearings, as well as bearing system stability predictions using thermohydrodynamic analysis and computational fluid dynamics (CFD), are considered as significant topics. Studies on SFDs mainly focus on experimental identification of force coefficients for various SFD geometries and sealing conditions. Reliable experiments of fluid film bearings and SFDs along with the development of experimentally benchmarked predictive tools enable reinforcement of the path for reliable implementations of the bearing components into high performance rotating machinery operating at extreme and harsh conditions. The extensive list of sources of recent experiments in the available open literature is a welcome addition to the analytical community to gauge the accuracy of predictive tools.

• Journal of Environmental Science International
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• v.25 no.5
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• pp.737-744
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• 2016

For electrolysis process using an insoluble electrode, electrochemical performance was greatly affected by the manufacturing method and procedure, such as the firing temperature, pre-treatment, type of precursor solution, coating method, electrode material, etc. Components of the electrode therein is one of the most important factors in electrochemical reaction. To achieve such characteristics, a appropriate ratio of the electrode material should be carefully chosen. The aim of this research was to apply experimental design method in the optimization of electrode component for the maximum generation of oxidants in electrochemical oxidation process. Mixture design, especially expanded simplex lattice design, in DOME (design of mixture experiments) with Design Expert - commercial software - was used to analyze the data. Analysis of variance (ANOVA) showed a high coefficient of determination ($R^2$) value of 0.9470, thus ensuring a satisfactory adjustment of the $3^{rd}$ order special cubic regression model with the experimental data. The application of response surface methodology (RSM) yielded the following regression equation, which is an empirical relationship between the TRO generation concentration and independent variables(mol ratio of 3 electrode components) in a real unit: TRO generation concentration $(mg/L)=TRO\;conc.=98.25{\times}[Ir]+49.71{\times}[Sn]+95.29{\times}[Sb]-16.91{\times}[Ir]{\times}[Sn]-29.47{\times}[Ir]{\times}[Sb]-22.65{\times}[Sn]{\times}[Sb]+703.19{\times}[Ir]{\times}[Sn]{\times}[Sb]$. The optimized formulation of the 3 component electrode for an high TRO (total residual oxidants) generation was acquired at mol ratio of Ir 0.406, Sn 0.210, Sb 0.384 (desirability d value, 1).

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.6
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• pp.1-9
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• 2011

In this study, the specifications of the components of the vent vale were optimally determined in order to enhance the performance of the vent valve. Design objective was to minimize fuel leakage while satisfying the design constraints on the performance indices. To obtain the optimum solution based on real experiments, several design techniques available in PIAnO, a commercial PIDO tool, were used. First, an orthogonal array was used to generate training design points and then real experiments were performed to measure the experimental data at the training design points. Next, Kriging metamodels for the objective function and design constraints were generated using the experimental data. Finally, a genetic algorithm was employed to obtain the optimization results using the Kriging models. Fuel leakage of the optimized vent valve was found to be reduced by 95.8% compared to that of the initial one while satisfying all the design constraints.