• 한국축산식품학회지
• /
• 제37권1호
• /
• pp.139-146
• /
• 2017

Response surface methodology (RSM) is a useful set of statistical techniques for modeling and optimizing responses in research studies of food science. In the analysis of response surface data, a second-order polynomial regression model is usually used. However, sometimes we encounter situations where the fit of the second-order model is poor. If the model fitted to the data has a poor fit including a lack of fit, the modeling and optimization results might not be accurate. In such a case, using a fullest balanced model, which has no lack of fit, can fix such problem, enhancing the accuracy of the response surface modeling and optimization. This article presents how to develop and use such a model for the better modeling and optimizing of the response through an illustrative re-analysis of a dataset in Park et al. (2014) published in the Korean Journal for Food Science of Animal Resources.

• 한국유체기계학회 논문집
• /
• 제16권4호
• /
• pp.22-27
• /
• 2013

The purpose of this paper is to perform the structural design of the small scale vertical-axis wind turbine (VAWT) blade using a response surface method(RSM). First, the four design factors that have a strong influence on the structural response of blade were selected. Analysis conditions were calculated by using the central composite design(CCD), which is a typical design of experiment for the response surface method(RSM). Also, the significance of the central composite design(CCD) was verified using analysis of variance(ANOVA). The finite element analysis was performed for the selected analytical conditions for the application of response surface method(RSM). Finally, a optimization problem was solved with a objective function of blade weight and a constraint of allowable stress to achieve a optimal structural design of blade.

• 한국축산식품학회지
• /
• 제39권1호
• /
• pp.114-120
• /
• 2019

Response surface methodology (RSM) is a useful set of statistical techniques for modeling and optimizing responses in research studies of food science. As a design for a response surface experiment, a central composite design (CCD) with multiple runs at the center point is frequently used. However, sometimes there exist situations where some among the responses at the center point are outliers and these outliers are overlooked. Since the responses from center runs are those from the same experimental conditions, there should be no outliers at the center point. Outliers at the center point ruin statistical analysis. Thus, the responses at the center point need to be looked at, and if outliers are observed, they have to be examined. If the reasons for the outliers are not errors in measuring or typing, such outliers need to be deleted. If the outliers are due to such errors, they have to be corrected. Through a re-analysis of a dataset published in the Korean Journal for Food Science of Animal Resources, we have shown that outlier elimination resulted in the increase of the maximum possible R-square that the modeling of the data can obtain, which enables us to improve the quality of response surface analysis.

• 한국항공우주학회지
• /
• 제40권4호
• /
• pp.336-345
• /
• 2012

균열성장 수명에는 구조 형상의 복잡함, 작용하중의 변동, 재료물성 분포 등의 영향으로 불확실성이 포함된다. 따라서 이러한 불확실 인자들에 대해 계산된 수명의 강건성을 확보하기 위해서는 신뢰성 평가가 요구된다. 하지만 형상이 복잡한 터빈 휠의 경우 균열성장 수명 계산의 주요 변수인 응력확대계수의 표현식을 알기 힘들며, 이를 유한요소해석으로 계산하므로 수명 계산 및 신뢰성 평가에 많은 시간이 요구된다. 따라서 본 연구에서는 균열성장 수명의 반응표면을 사용함으로써 신뢰성 평가의 효율성을 높일 수 있음을 고찰하였다. 이를 위해 형상이 복잡한 터빈 휠을 모델로 유한요소해석으로 생성된 응력확대계수 데이터를 회귀분석하여 근사모델을 생성한 후 응력확대계수의 회귀계수, Paris 계수, 초기균열길이에 대한 균열성장 수명의 반응표면을 생성하여 신뢰성해석에 사용하였다. 신뢰성해석은 몬테카를로 시뮬레이션으로 수행하였으며, 연구결과 반응표면의 사용이 신뢰성 평가 시 필요한 균열성장 수명의 계산량을 효과적으로 줄일 수 있었다.

• 한국응용과학기술학회지
• /
• 제21권2호
• /
• pp.148-155
• /
• 2004

Response surface analysis was used to study dietary ratios of n-3/n-6 fatty acid and P/S to minimize plasma triglycerides, total cholesterol and LDL ${\cdot}$ VLDL-C levels and maximize plasma HDL ${\cdot}$ C levels of rats. Because the dietary components were not statistically independent, they were studied in combinations of two variables. The two-variable combinations were the most useful in locating the desired maximum or minimum plasma triglycerides, total cholesterol and LDL ${\cdot}$ VLDL-C response in terms of the proportions of the dietary components. Response surface contours and three dimensional plots were developed for each plasma lipid response. The contours and three dimensional plots were used to help determine those combinations of the dietary fatty acid ratios that would produce the desired minimum or maximum lpid responses. The statistical analyses indicated that the minimized plasma cholesterol response levels could be attained with a diet consisting of 2.26 n-3/n-6 fatty acid and 2.15 P/S ratios.

• Geomechanics and Engineering
• /
• 제15권4호
• /
• pp.937-945
• /
• 2018

A probabilistic study of a reinforced earth wall in a frictional soil using the surface response methodology (RSM) is presented. A deterministic model based on numerical simulations is used (Abdelouhab et al. 2011, 2012b) and the serviceability limit state (SLS) is considered in the analysis. The model computes the maximum horizontal displacement of the wall. The response surface methodology is utilized for the assessment of the Hasofer-Lind reliability index and is optimized by the use of a genetic algorithm. The soil friction angle and the unit weight are considered as random variables while studying the SLS. The assumption of non-normal distribution for the random variables has an important effect on the reliability index for the practical range of values of the wall horizontal displacement.

• Structural Engineering and Mechanics
• /
• 제62권2호
• /
• pp.139-142
• /
• 2017

For the conventional computational methods for structural reliability analysis, the common limitations are long computational time, large number of iteration and low accuracy. Thus, a new novel method for structural reliability analysis has been proposed in this paper based on response surface method incorporated with an improved genetic algorithm. The genetic algorithm is first improved from the conventional genetic algorithm. Then, it is used to produce the response surface and the structural reliability is finally computed using the proposed method. The proposed method can be used to compute structural reliability easily whether the limit state function is explicit or implicit. It has been verified by two practical engineering cases that the algorithm is simple, robust, high accuracy and fast computation.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2002년도 춘계공동학술발표회요약집
• /
• pp.54-54
• /
• 2002

• 품질경영학회지
• /
• 제27권1호
• /
• pp.165-194
• /
• 1999

Taguchi's parameter design seeks proper choice of levels of controllable factors (Parameters in Taguchi's terminology) that makes the qualify characteristic of a product optimal while making its variability small. This aim can be achieved by response surface techniques that allow flexibility in modeling and analysis. In this article, a collection of response surface modeling and analysis techniques is proposed to deal with the multiresponse optimization problem in experimentation with Taguchi's signal and noise factors.

• Geomechanics and Engineering
• /
• 제15권6호
• /
• pp.1207-1217
• /
• 2018

Geomechanics parameters are critical to numerical simulation, stability analysis, design and construction of geotechnical engineering. Due to the limitations of laboratory and in situ experiments, back analysis is widely used in geomechancis and geotechnical engineering. In this study, a hybrid back analysis method, that coupling numerical simulation, response surface (RS) and relevance vector machine (RVM), was proposed and applied to identify geomechanics parameters from hydraulic fracturing. RVM was adapted to approximate complex functional relationships between geomechanics parameters and borehole pressure through coupling with response surface method and numerical method. Artificial bee colony (ABC) algorithm was used to search the geomechanics parameters as optimal method in back analysis. The proposed method was verified by a numerical example. Based on the geomechanics parameters identified by hybrid back analysis, the computed borehole pressure agreed closely with the monitored borehole pressure. It showed that RVM presented well the relationship between geomechanics parameters and borehole pressure, and the proposed method can characterized the geomechanics parameters reasonably. Further, the parameters of hybrid back analysis were analyzed and discussed. It showed that the hybrid back analysis is feasible, effective, robust and has a good global searching performance. The proposed method provides a significant way to identify geomechanics parameters from hydraulic fracturing.