• 한국안전학회지
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• 제31권1호
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• pp.25-32
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• 2016

A sensitivity analysis of FDS(Fire Dynamics Simulator) results for the input uncertainty of heat release rate (Q) which might be the most influencing parameter to fire behaviors was performed. The calculated results were compared with experimental data obtained by the OECD/NEA PRISME project. The sensitivity of FDS results with the change in Q was also compared with the empirical correlations suggested in previous literature. As a result, the change in the specified Q led to the different dependence of major quantities such as temperature and species concentrations for the over- and under-ventilated fire conditions, respectively. It was also found that the sensitivity of major quantities to uncertain value of Q showed the significant difference in results obtained using the previous empirical correlations.

• 한국기계가공학회지
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• 제19권11호
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• pp.29-34
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• 2020

In this study, a sensitivity formulation was applied to analyze the dynamic response due to the effect of the excitation force for the undamped vibration of the cantilever beam. The theoretically fundamental formulations were derived considering an eigenvalue problem and its modal analysis to govern the second order algebraic differential equation in terms of the change in the modal coordinate with respect to the design parameters. A representative physical quantity pertaining to the dynamic response, that is, the rate of change in the dynamic displacement, was observed by changing the design variables, such as the cross-sectional area of the beam. The numerical results were obtained at various locations, considering the application of the external forces and observation of the dynamic displacement. When the detection position was closer to the free end of the cantilever beam, the sensitivity of the dynamic displacement was higher, as predicted through the oscillating motion of the beam. The presented findings can provide guidance to compute the dynamic sensitivity for a flexibly connected structure under dynamic excitations.

• Journal of Microbiology and Biotechnology
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• 제4권1호
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• pp.13-19
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• 1994

A model equation to describe the plasmid instability in recombinant Escherichia coli fermentation is proposed. The equation allows one to estimate easily the two model parameters; (1) the difference in the specific growth rates between plasmid-free cells and plasmid-harboring cells ($\delta$), and (2) the probability of plasmid loss by plasmid-harboring cells ($\rho$). The estimated values of $\delta and \rho$ were in the range of 0.02-0.07 and $10^{-3}-10^{-5}$, respectively, and were strongly dependent on the dilution rate. As another parameter, the ratio of specific growth rates of plasmid-free cells and plasmid-harboring cells ($\alha$) was calculated and the result showed the highest value of 1.28 at the lowest dilution rate of 0.075 $hr^{-l}$, examined in this work. By the sensitivity analyses on the estimates of $\delta and \rho$, it was found that the growth rate difference ($\delta$) affected the plasmid instability more seriously than the probability of plasmid loss ($\rho$). Furthermore, the profound instability of plasmid at low dilution rate could be explained by the high values of $\alpha and \rho$.

• 한국농공학회논문집
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• 제50권2호
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• pp.3-10
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• 2008

The main objectives of this study are to calibrate the RICEWQ model with Korean field data and then analyse the sensitivity of the parameters to identify sensitive parameters. The RICEWQ is widely used to predict pesticide fate in a paddy plot. An experimental paddy plot of 0.2 ha($100{\times}20\;m$) at Seobyeon-dong, Daegu, Korea was selected, and field observations for water and pesticide balance were performed from 4 June to 2 September 2006. The molinate, which is a herbicide widely used for weed control in rice culture, was selected. The RICEWQ model was successfully calibrated both for the water and pesticide mass balance. The calibrated model showed a RMSE of 0.537 cm for ponded water depths and a RMSE of 0.036 mg/L for the molinate concentrations in the ponded water. The most sensitive parameters for molinate concentrations in ponded water were the metabolism degradation rate in water, volatilization coefficient, and release rate for slow release formulation. In contrast, the RICEWQ model was not sensitive to parameters such as hydrolysis degradation rate in water and degradation rate in unsaturated soil.

• KSBB Journal
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• 제13권5호
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• pp.477-482
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• 1998

A biosensor with PZT piezoelectric ceramic crystal was developed for the detection of formaldehyde gas. Poled PZT piezoelectric ceramic disk was made from ZrO2, TiO2 and Nb2O5, together with the addition of PbO and polyvinyl alcohol, through various processes of mixing, calcination drying, crushing, forming, sintering, polishing, ion coating and poling. Oscillator circuit of sensor was made of operational amplifier(AD811AN). Formaldehyde dehydrogenase was immobilized onto a piezoelectic ceramic crystal, together with the cofactors, reduced glutathione and nicotinamide adenine dinucleotide. The effect of flow rate on the sensitivity was determined by varing the flow rate of carrier gas from 24.7mL/min to 111.7mL/min through detector cell. The results indicated that as the flow rate was increased, the recovery rate was increased. And a significant increase in the sensitivity was observed in enhanced flow rate of carrier gas. Frequency difference(ΔF) of immobilized PZT piezoelectic disk increased proportionally to the concentration gas and reproduced to repeated exposures of formaldehyde gas(28ppm, Δ68Hz).

• 대한기계학회논문집
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• 제15권2호
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• pp.537-543
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• 1991

In this study, the strain rate effects are considered in the formulation by introducing the constitutive equation of the strain rate sensitive materials and rigid-viscoplastic finite element program is developed for axisymmtric extrusion. The effect of strain rate sensitivity on the flow characteristics and forming pressure are investigated and the experiments are carried out for extrusion with pure lead specimens. The theoretically predicted forming pressure showed reasonably good agreement with the experimental values.

• 한국항공운항학회지
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• 제18권1호
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• pp.51-57
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• 2010

This study was to analyze the difference in pilot error by using the Signal Detection Theory. The task was to detect the targeted aircraft(signal) which is different shape from many other aircraft(noise). From the two experiments, we differentiated the task difficulty followed by change in noise stimuli. Experiment 1 was to search the signal stimuli(fighter plane) while the noise stimuli(cargo plane) were increasing. The results from the Experiment 1 showed the tendency to decrease the hit rate by increasing the number of noise stimuli. However, the false alarm rate was not increased. The sensitivity(d') showed quite high. In Experiment 2, a disturbance stimulus(helicopter) was added to noise stimuli. The result was generally similar to those of Experiment 1. However, the hit rate was lower than that of Experiment 1.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.543-547
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• 2001

CAE has been settled down to an indispensable tool for the simulation of a mechanical system according to the development of computer-aided analysis rapidly. Particularly finite element programs have advanced to the one of most valuable things in the filed of CAE due to the remarkable progress in the implementation. But since this analysis tool mostly provides the result of the analysis, it cannot satisfy designers who are seeking for information to improve their designs. Therefore, design sensitivity analysis or optimization module has been incorporated into commercial FEA programs to satisfy the desire of designers since 1990s. Design sensitivity analysis is to compute the rate of change of response with respected to design variable. Design sensitivity analysis is classfied into static design sensitivity analysis, Eigenvalue design sensitivity analysis and dynamic design sensitivity analysis. In this research, it will be presented to nonlinear static design sensitivity analysis formulation and nonlinear static design sensitivity analysis external module based ANSYS have been developed and illustrated an example to verify the developed module.

• 패션비즈니스
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• 제16권5호
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• pp.164-177
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• 2012

The purpose of this study was to classify sex role identity into groups and analyze the difference of social face sensitivity and appearance management behaviors by sex role identity. Questionnaires were administered to 306 people in their twenties and thirties living in Daegu Metropolitan City and Kyoungbuk province. The data was analyzed by using frequency, factor analysis, credibility, ${\chi}^2$-test, ANOVA, Duncan-test, and t-test. The findings were as follows. Sex role identity were classified into four groups (androgyny, masculineness, feminineness, and undifferentiation). Men in androgyny group showed the highest rate of 41.3% followed by undifferentiation(24.7%), masculineness(21.3%), and feminineness(12.7%). Women in undifferentiation group showed the highest rate of 35.9% followed by feminineness(24.4%), androgyny(23.7%), and masculineness(16.0%). Social face sensitivity were composed of four factors (consciousness of being embarrassed, social formality, other consciousness, and prestige). Appearance management behaviors were composed of six factors (skin management, fashion image management, plastic surgery management, weight management, hair management, and health management). According to the result of a significant difference between social face sensitivity and appearance management behaviors by sex role identity, male showed significant difference between the sub-variables of social face sensitivity factors (consciousness of being embarrassed, social formality, and other consciousness). Both of the male and female showed a significance of difference in consciousness of being embarrassed, and social formality. Male showed significant difference between the sub-variables of appearance management behaviors factors (fashion image management, weight management, hair management, and health management). Both of the male and female showed a significance of difference in fashion image management. Gender of twenties and thirties showed distinction between the sub-variables of social face sensitivity factors (consciousness of being embarrassed, and prestige) and appearance management behaviors (skin management, fashion image management, plastic surgery management, weight management, and hair management).

• Asian-Australasian Journal of Animal Sciences
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• 제19권7호
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• pp.1010-1018
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• 2006

A glucose clamp technique was used to investigate the effects of non-protein energy intake on tissue responsiveness and sensitivity to insulin for glucose metabolism in intact adults male goats. Three goats were fed diets at 1.0, 1.5 and 2.0 times of ME for maintenance, each for 21 d. Crude protein intake was 1.5 times of maintenance requirement in each treatment. Tissue responsiveness and sensitivity to insulin were evaluated using a hyperinsulinemic euglycemic clamp technique with four levels of insulin infusion, beginning at 13 h after feeding. Concentrations of plasma metabolites and insulin were also measured at 3, 6 and 13 h after feeding, for evaluating effects of non-protein energy intake on the metabolic status of the animals. Increasing non-protein energy intake prevented an increase in plasma NEFA concentration at 13 h after feeding (p = 0.03). Plasma urea-nitrogen and total amino-nitrogen concentrations decreased (p<0.01) and increased (p = 0.03), respectively, with increasing non-protein energy intake across time relating to feeding. Plasma insulin concentration was unaffected (p = 0.43) by non-protein energy intake regardless of time relating to feeding. In the glucose clamp experiment, increasing non-protein energy intake decreased numerically (p = 0.12) the plasma insulin concentration at half-maximal glucose infusion rate (insulin sensitivity), but did not affect (p = 0.60) maximal glucose infusion rate (tissue responsiveness to insulin). The present results suggest that an increase in non-protein energy intake may enhance insulin sensitivity for glucose metabolism, unlike responsiveness to insulin, in adult male goats. The possible enhancement in insulin sensitivity may play a role in establishing anabolic status in the body, when excess energy is supplied to the body.