• Preventive Nutrition and Food Science
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• 제13권2호
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• pp.104-111
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• 2008

As a way to account for the variability of the primary model parameters in the secondary modeling of microbial growth, three different regression approaches were compared in determining the confidence interval of the temperature-dependent primary model parameters and the estimated microbial growth during storage: bootstrapped regression with all the individual primary model parameter values; bootstrapped regression with average values at each temperature; and simple regression with regression lines of 2.5% and 97.5% percentile values. Temperature dependences of converted parameters (log $q_o$, ${\mu}_{max}^{1/2}$, log $N_{max}$) of hypothetical initial physiological state, maximum specific growth rate, and maximum cell density in Baranyi's model were subjected to the regression by quadratic, linear, and linear function, respectively. With an advantage of extracting the primary model parameters instantaneously at any temperature by using mathematical functions, regression lines of 2.5% and 97.5% percentile values were capable of accounting for variation in experimental data of microbial growth under constant and fluctuating temperature conditions.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.96-99
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• 2008

When the design modification is occurred, at present, design process based on 2-D spend more time and effort than that based on 3-D to modify related structural details. To improve and develop these processes, therefore, the design possibility of civil structures based on virtual model of 3-D must be investigated. We designed reinforced concrete pier of 3-D model, containing parameters. The parameters was defined as structural details like area of the section, reinforcement specification for design modification and structural analysis. In this paper, we researched about the processes modeling of reinforced concrete bridge pier based on parameters, the extracting data from the virtual model of 3-D, and the reflection of data to virtual model throughout structural analysis.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.585-594
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• 2009

In this present study, to performed the model test and estimated the behavior characteristics of twin tunnel in accordance with the variation of the whole failure parameters which is the strength of the ground, distance of tunnel, angle of the joint, installation of tension bolts and the blasting load. To carry out the numerical analysis for verification of model test results and analyze the sensitivity on failure parameters using model test and numerical analysis results. Based on sensitivity analysis results, to propose the most habitually failure parameters in tunnel scale model test.

• Smart Structures and Systems
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• 제30권5호
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• pp.447-462
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• 2022

The viscosity of a shear-thickening fluid damper (STFD) can increase dramatically when the STFD undergoes high-rate of excitation. Therefore, accurate numerical modelling of the STFD has been considered difficult due to this distinct feature. This study aims to develop a numerical model to accurately simulate the response of the STFD. First, a STFD is designed, fabricated, and installed in the laboratory. Then, performance tests are conducted in which sine waves with nine frequencies at three amplitude levels are adopted as the displacement excitations to the STFD. A novel numerical model which contains two parameter sets of the discrete Bouc-Wen model as well as two parameters for transiting the two parameter sets. Therefore, a total number of eighteen parameters need to be identified in the damper model. The symbiotic organisms search is applied to optimize the parameters. Numerical simulation results demonstrate that the proposed STFD model with transit parameter sets outperforms the conventional discrete Bouc-Wen model. The proposed STFD model can be applied to analyses of structures in which STFDs are installed in the future.

• Earthquakes and Structures
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• 제25권1호
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• pp.15-26
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• 2023

It is of great importance to assess the residual displacement demand in the performance-based seismic design. In this paper, a hybrid deep learning model for predicting the residual displacement spectra under near-fault (NF) ground motions is proposed by combining the long short-term memory network (LSTM) and back-propagation (BP) network. The model is featured by its capacity of predicting the residual displacement spectrum under a given NF ground motion while considering the effects of structural parameters. To construct this model, 315 natural and artificial NF ground motions were employed to compute the residual displacement spectra through elastoplastic time history analysis considering different structural parameters. Based on the resulted dataset with a total of 9,450 samples, the proposed model was finally trained and tested. The results show that the proposed model has a satisfactory accuracy as well as a high efficiency in predicting residual displacement spectra under given NF ground motions while considering the impacts of structural parameters.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.543-547
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• 2002

In this paper, we introduce a more improved camera modeling method for linear pushbroom images than the method proposed by Orun and Natarajan(ON). ON model shows an accuracy of within 1 pixel if more than 10 ground control points(GCPs) are provided. In general, there is high correlation between platform position and attitude parameters but ON model ignores attitude variation in order to overcome such correlation. We propose a new method that obtains an optimal solution set of parameters without ignoring the attitude variation. We first assume that attitude parameters are constant and estimate platform position's. Then we estimate platform attitude parameters using the values of estimated position parameters. As a result, we can set up an accurate camera model for a linear pushbroom satellite scene. In particular, we can apply the camera model to its surrounding scenes because our model provide sufficient information on satellite's position and attitude not only for a single scene but also for a whole imaging segment. We tested on two images: one with a pixel size 6.6m$\times$6.6m acquired from EOC(Electro Optical Camera), and the other with a pixel size 10m$\times$l0m acquired from SPOT. Our camera model procedures were applied to the images and gave satisfying results. We had obtained the root mean square errors of 0.5 pixel and 0.3 pixel with 25 GCPs and 23 GCPs, respectively.

• 한국수자원학회논문집
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• 제36권2호
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• pp.223-235
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• 2003

Clark 모형의 매개변수 추정방법을 개선하기 위하여, 순간단위도를 gamma 분포형 함수로 가정하여 매개변수를 추정한 후 이를 Clark 모형의 매개변수로 전환하는 간접 추정방법을 제안하였다. 이 방법은 전통적인 Clark 모형의 매개변수 추정방법의 개연적인 부정확성을 개선하는 특징과 더불어 Nash 모형과의 상관성을 파악할 수 있는 장점을 갖고 있다. 제안된 매개변수 추정방법을 위천 유역에 적용한 결과 만족할 수 있는 수준의 추정값을 얻을 수 있었으며 또한 유역의 도달시간-유하면적 관계를 나타내는 합성함수를 구축할 수 있었다. 또한 제안된 매개변수 추정방법은 미계측 유역에 대한 추정에 있어서도 높은 적용성을 보였다. 따라서 제안된 방법론은 기존의 매개변수 추정방법을 보조할 수 있는 충분한 대안으로 판단된다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.107-111
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• 2009

The parameters in the Horton's model which has well known as typical infiltration model were determined by the use of the optimization technique. It was assumed the initial infiltration capacity in this model was related to the antecedent precipitation per 10 days with linear combination. And both the parameters of the ultimate infiltration capacity and the decay factor were determined uniquely on a basin. Thus the optimal model's parameters representative to a basin were obtained and the Horton's infiltration equations by rainstorm events were determined. The data of ten rainstorm events for this study were observed at the Jeonjeokbigyo station located at the Selmacheon experimental basin that was $8.5\;km^2$ wide in the Imjin river.

• 한국광학회지
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• 제33권6호
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• pp.324-330
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• 2022

포토레지스트의 노광 및 현상 특성을 각각 결정하는 Dill 및 Mack 모델 파라미터들을 측정하였다. 먼저, 노광량을 변화시켜가며 포토레지스트 샘플을 준비하였고, 노광량에 따른 투과율 변화를 측정하였다. 이 결과를 바탕으로 Dill 모델의 A, B, C 파라미터를 결정하였는데, 특히 C 파라미터를 결정하기 위하여 Dill 모델 방정식의 완전해를 사용하였다. 또한, 노광량별로 현상 시간에 따른 포토레지스트의 두께 변화를 측정하였고, 이 결과를 사용하여 Mack 모델의 R_min, R_max, a, n 파라미터를 결정하였다. 모델 파라미터 R_min, R_max, n만을 사용하는 간략화된 Mack 모델에 대해서도 파라미터값들을 결정해 보았는데, 네 개의 파라미터를 사용하는 본래 Mack 모델의 경우와 비교했을 때 측정결과와의 오차가 다소 커짐을 알 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.805-810
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• 2004

The model is verified thorough simulations and experiments. And then the developed model is applied to a half car model and automobile vibrations are analyzed. The effects of tire design parameters on the automobile vibration energy are investigated. The results from laboratory and field tests confirm the validity of the analytical model. The 17-DOF half-car model is built to analyze the automobile vibration. The characteristics of the nonlinear model for a shock absorber are applied to this model. The results from the present 17-DOF half car model incorporating the analytical tire model with tire design parameters, are compared with a 5-DOF half car model where the tire is modeled with linear springs. The results of the 17-DOF model are closed to experimental results. Using the 17-DOF model, the influences of tire design parameter are considered. According to the results of analyses, the vibrations at seat/body/wheel are predicted by simulation and experiment.