• Food Science and Preservation
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• v.24 no.5
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• pp.623-630
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• 2017

Functional compounds including flavonoids, anthocyanins, polyphneols and antioxidants were extracted from blue honeysuckle (Lonicera caerulea L.) using highly efficient microwave-assisted extraction. And extraction process was modeled and optimized according to response surface methodology (RSM). The independent variables ($X_n$) were ethanol concentration ($X_1$: 0, 25, 50, 75, 100%), irradiation time ($X_2$: 1, 3, 5, 7, 9 min), and microwave power ($X_3$: 60, 120, 180, 240, 300 W). Dependent variables ($Y_n$) were total flavonoid contents ($Y_1$), total anthocyanin contents ($Y_2$), total polyphenol contents ($Y_3$) and antioxidant activity ($Y_4$). Four-dimensional response surface plots were generated based on the fitted second-order polynomial models to get optimal conditions. Estimated optimal conditions for 4 responses were ethanol concentration of 54-72%, irradiation time of 7.1-7.6 min, and microwave power of 243-251 W. Ridge analysis predicted the maximal responses of total flavonoid content, total anthocyanin content, total polyphenol content and antioxidant activity were 38.00 mg RE/g, 6.80 mg CGE/g, 14.90 mg GAE/g, 89.10%, respectively. Verification experiment was carried out at predicted optimal conditions and experimental values for total flavonoid content, total anthocyanin content, total polyphenol content and antioxidant activity were 38.10 mg RE/g, 6.72 mg CGE/g, 14.91 mg GAE/g and 89.13%, respectively. No significant difference was observed between predicted and experimental values, indicating good fitness of fitted model and successful application of RSM.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.4
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• pp.65-75
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• 1993

Presented is a method for nonstationary response analysis of an offshore guyed tower subjected to strong earthquake motions under moderate random waves and current loadings. By taking the time varying envelope function and the auto-correlation function of the ground acceleration in terms of complex exponential functions, an analytical procedure is developed for computing time varying variances of the tower response. The stationary responses due to small random waves are obtained by using frequency domain method, and the results are combined with the nonstationary results due to earthquakes. Finally, the expected maximum responses are estimated. Through the example analyses, the nonstationary method developed in this study is verified, and the contributions of the earthquake, wave and current loadings to the total maximum response are investigated.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.10 no.2
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• pp.64-72
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• 1998

Dynamic response analysis is carried out for slender marine structures such as tensioned risers and tethers of tension leg platform, which are subjected to floating vessel motions as well as environmental forces arising from ocean waves. A mumerical analysis procedure is developed by using finite element model of the structural member. Dynamic analses are performed in the time domain for regular waves. Parameter studies are carried out to highlight the effects of surface vessel motions on the lateral dynamics of the structures. Example results of displacements, bending stresses are compared for various in water depth, environmental condition and vessel motion. Some instability conditions of the structures due to time-varying tension by vessel heave motion are discussed through the example analyses. As the results, the interaction between vessel surge and heave motions amplifies the total structural response of a riser. In the case of a tether, the effect of vessel heave motion during heavy storm is seemed to be quite significant to lateral response of the structure.

• The Journal of Korean Society for School & Community Health Education
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• v.18 no.1
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• pp.1-12
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• 2017

Objectives: This study aimed to analyze sexual experience rates according to socio-demographic factors, health behavioral factors, and internet use time, and to identify sex experience related factors in high school students using the data from the 11th Korean Youth Health Risk Behavior Web-Based Survey. Methods: A total of 33,744 students (17,346 boys and 16,398 girls) in high schools were analyzed using the SPSS WIN version 22 program. SPSS complex samples methods were used for analyses. Socio-demographic factors, health behavioral factors, and internet use time as independents variables were included. The complex samples logistic regression analyses were used to calculate the odds ratio of the sexual experience according to the socio-demographic factors, health behavioral factors and internet use time. Unweighted frequencies and percentages were represented in result tables. Results: 3.6% of girls and 9.9% of boys in high school had sexual experiences. Daily average smoking amount and daily alcohol drinking amount were a dose-response relationship with sexual experience after considering confounding factors. Students who smoke 10-19 cigarettes had 5.74 times higher risk and 20 cigarettes or more had 7.27 times higher risk of sexual experiences, comparing with non-smoking students, relatively. Likewise, students who drink soju less than 1-2 bottles and more than 2 bottles had 3.82- and 4.35 times higher chance of sexual experiences, compared with non drinking students, respectively. Conclusions: We found that there were the dose-response relationship between health behavioral characteristics and sexual experiences. Further research is needed to identify an interaction effect between smoking and drinking alcohol on sexual experiences in high school students.

• Steel and Composite Structures
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• v.41 no.5
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• pp.761-773
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• 2021

This study presents a 3D non-linear finite element (FE) assessment of dynamic soil-structure interaction (SSI). The numerical investigation has been performed on the time domain through a Finite Element (FE) system, while considering the nonlinear behavior of soil and the multi-directional nature of genuine seismic events. Later, the FE outcomes are analyzed to the recorded in-situ free-field and structural movements, emphasizing the numerical model's great result in duplicating the observed response. In this work, the soil response is simulated using an isotropic hardening elastic-plastic hysteretic model utilizing HSsmall. It is feasible to define the non-linear cycle response from small to large strain amplitudes through this model as well as for the shift in beginning stiffness with depth that happens during cyclic loading. One of the most difficult and unexpected tasks in resolving soil-structure interaction concerns is picking an appropriate ground motion predicted across an earthquake or assessing the geometrical abnormalities in the soil waves. Furthermore, an artificial neural network (ANN) has been utilized to properly forecast the non-linear behavior of soil and its multi-directional character, which demonstrated the accuracy of the ANN based on the RMSE and R² values. The total result of this research demonstrates that complicated dynamic soil-structure interaction processes may be addressed directly by passing the significant simplifications of well-established substructure techniques.

• Journal of the Korean Society for information Management
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• v.5 no.2
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• pp.145-160
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• 1988

111 this paper, ~vc atialyzed thr, staristical data logged by rlte library itiformatio~~ rrtrieval system n41icli was developed it1 K'I'A as a part of total system. System performance was measured numerically b\. means of tables and graphs reprc.ieritmg the usage patterns, die response times, and tl~e success ratt.5 of each stxiircIii~rg item.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.318-318
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• 1994

Addition of AAF to murine splenocytes culture produced a dose-related suppression of lymphoproliferative response to lipopolysaccharide (LPS). The time course of the suppression showed that a significant inhibition was occured after a 18 hr AAF treatment. Total protein kinase C activity in splenocytes was decreased to 72% of control level after a 18 hr AAF treatment. Phosphorylation of a PKC specific 80 kDa protein was increased by LPS and AAF down-regulated LPS-induced PKC activity. LPS-induced phosphorylation of overall proteins in membrane and cytosolic fraction were also decreased by the treatment of AAF. A significant increase of PKC activity in membrane fraction was noticed within 10 min of AAF treatment compared to LPS alone and then gradually decreased to LPS level in 60 min. Meanwhile, PKC activity in cytosolic fraction was increased slightly in 10 min by the treatment of AAF and then decrease to 80% LPS level in 30 min. These results suggested that suppressive effect of AAF on LPS-induced lymphoproliferative response may be associated with the down-regulation of PKC and other susceptible kinases in spleen cells.

• Journal of Electrical Engineering and Technology
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• v.6 no.6
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• pp.769-775
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• 2011

Custom power devices such as dynamic voltage restorer (DVR) and DSTATCOM are used to improve the power quality in distribution systems. These devices require real power to compensate the deep voltage sag during sufficient time. An interline DVR (IDVR) consists of several DVRs in different feeders. In this paper, a neural network is proposed to control the IDVR performance to achieve optimal mitigation of voltage sags, swell, and unbalance, as well as improvement of dynamic performance. Three multilayer perceptron neural networks are used to identify and regulate the dynamics of the voltage on sensitive load. A backpropagation algorithm trains this type of network. The proposed controller provides optimal mitigation of voltage dynamic. Simulation is carried out by MATLAB/Simulink, demonstrating that the proposed controller has fast response with lower total harmonic distortion.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.867-871
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• 2009

Response surface methodology (RSM) was used for the optimization of antioxidant capacity in gardenia extracts. The antioxidant capacities of gardenia fruit extracts were investigated by ferric reducing ability (FRA) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity (RSA) assays. The optimum extraction parameters for the strongest antioxidant capacity were the ethanol concentration (EtOH) of 48.9%, extraction temperature of $72.9^{\circ}C$, and extraction time of 29.9 min. Analysis of variance (ANOVA) showed that the quadratics of EtOH and extraction temperature had highly significant effect on the antioxidant capacity (p<0.001). The antioxidant capacity was correlated with contents of bioactive components [crocin, geniposide, and total phenolic (TP) compounds] in gardenia extracts and mainly attributed to the content of the TP compounds.

• Structural Engineering and Mechanics
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• v.4 no.2
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• pp.111-124
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• 1996

New active "intelligent" structural systems with integrated self-sensing, diagnosis, and control capabilities can lead to a new design dimension for the next generation high-performance structures and mechanical systems. However, temperature effects to the piezoelectric transducers are not fully understood. This paper is concerned with a mathematical modeling and analysis of a laminated piezothermoelastic cylindrical shell composite exposed to mechanical, electric, and thermal fields. Generic shell equations and solution procedures are derived. Contributions of spatial and time components in the mechanical, electric, and temperature excitations are discussed, and their analytical solutions derived. A laminated cylindrical shell composite with fully distributed piezoelectric layers is used in a case study; its multi-field step and impulse responses are investigated. Analyses suggest that the fully distributed actuators are insensitive to even modes due to load averaging and cancellation. Accordingly, these even modes are filtered from the total response and only the modes that are combinations of m = 1, 3, 5, ${\cdots}$ and n = 1, 3, 5, ${\cdots}$ participating in dynamic response of the shell.