• Geomechanics and Engineering
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• v.20 no.1
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• pp.43-54
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• 2020

The limit analysis and response surfaces method were combined to investigate the reliability of pressurized tunnel faces subjected to seismic force. The quasi-static method was utilized to introduce seismic force into the tunnel face. A 3D horn failure mechanism of pressurized tunnel faces subjected to seismic force was constructed. The collapse pressure of pressurized tunnel faces was solved by the kinematical approach. The limit state equation of pressurized tunnel faces was obtained according to the collapse pressure and support pressure. And then a reliability model of pressurized tunnel faces was established. The feasibility and superiority of the response surfaces method was verified by comparing with the Monte Carlo method. The influence of the mean of soil parameters and support pressure, variation coefficients, distribution type and correlation of c-φ on the reliability of pressurized tunnel faces was discussed. The reasonable safety factor and support pressure required by pressurized tunnel faces to satisfy 3 safety levels were presented. In addition, the effects of horizontal seismic force, vertical seismic force and correlation of k_h-k_v on the reliability of pressurized tunnel faces were also performed. The method of this work can give a new idea for anti-seismic design of pressurized tunnel faces.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.5
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• pp.630-639
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• 2010

Immune response and yolk cholesterol are crucial factors for commercial chicken producers. The objectives of this study were to investigate the effect of selenium-enriched Japanese radish sprouts (Se-enriched JRS) and R. capsulatus synergistically on immune response and cholesterol in laying hens. A total of 50 laying hens (20-wk old) were assigned to 5 dietary treatment groups, and fed diets supplemented with 2.5 ${\mu}g/kg$, 5 ${\mu}g/kg$, 10 ${\mu}g/kg$ Se-enriched JRS and 5 ${\mu}g/kg$ Se-enriched JRS+R. capsulatus (0.02%). Egg production and yolk color were significantly improved by the supplementation of Se-enriched JRS+R. capsulatus in the layer diet (p<0.05). Compared to the control, serum cholesterol concentration and triglyceride levels were decreased by all the treatments (p<0.05). After 8-wk of the experiment, supplementation of 5 ${\mu}g/kg$, 10 ${\mu}g/kg$ and Se-enriched JRS+R. capsulatus significantly reduced yolk cholesterol and triglycerides, while the greatest reduction was observed when R. capsulatus was incorporated with Se-enriched JRS. Spleen, bursa and thymus weight were significantly increased by both the 5 ${\mu}g/kg$ and 10 ${\mu}g/kg$ Se-enriched JRS. Compared to the control, supplementation of 5 ${\mu}g/kg$ and 10 ${\mu}g/kg$ Se-enriched JRS significantly increased serum IgG and yolk IgY concentration and foot web index activity by Newcastle Disease Virus (p<0.05). After 4-wk and 8-wk of supplementation, the highest number of leukocytes was observed with Se-enriched JRS+R. capsulatus (p<0.05). The highest concentration of serum and yolk Se was found in Se-enriched JRS plus R. capsulatus treatment. Combined dietary supplementation of Se-enriched JRS and R. capsulatus might be beneficial for better health, disease protection and overall production performance.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.265-282
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• 2018

The purpose of this research was to produce symmetric (Saturated-Unsaturated-Saturated, SUS) triacylglycerol (TAG) using palm stearin fraction oil (PSFO) and high oleic sunflower oil (HOSO) as substrates to replace cocoa butter. PSFO was blended with HOSO (1 : 2 weight ratio), and $lipozyme^{(R)}$ TLIM (20 weight % of the substrate) was added. Interesterification was carried out in a shaking water bath at $55^{\circ}C$ at 220 rpm for 6 hours. The response surface methodology (RSM) through the central composite face design was employed to observe the optimized SUS-TAG. The independent factors were the reaction temperature ($X_1$: 65, 75 and $85^{\circ}C$), reaction time ($X_2$: 1, 3 and 5 hours) and ratio of TLIM ($X_3$: 10, 15 and 20 weight %). The dependent variables were $Y_1$ = Saturated-Unsaturated-Unsaturated (SUU, area %), $Y_2=SUS$ (area %), $Y_3$ = Saturated-Saturated-Unsaturated (SSU, area %), $Y_4$ = Unsaturated-Unsaturated-Unsaturated (UUU, area %), and $Y_5=sn-2$ unsaturated fatty acid (area %). The optimal conditions from the central composite face design minimized acyl migration while maximizing the presence of unsaturated fatty acid at the sn-2 position (73.43 area %). The optimal conditions were $X_1=65^{\circ}C$, $X_2=1hour$, and $X_3=20weight%$. As a result of the response surface analysis, the lack of fits was found as $Y_1=0.622$, $Y_2=0.438$, $Y_3=0.264$, $Y_4=0.526$, and $Y_5=0.215$, and their $R^2$ were 0.897, 0.944, 0.826, 0.857, and 0.867, respectively.

• Journal of Veterinary Science
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• v.22 no.3
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• pp.30.1-30.15
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• 2021

Background: New-generation adjuvants for foot-and-mouth disease virus (FMDV) vaccines can improve the efficacy of existing vaccines. Chinese medicinal herb polysaccharide possesses better promoting effects. Objectives: In this study, the aqueous extract from Artemisia rupestris L. (AEAR), an immunoregulatory crude polysaccharide, was utilized as the adjuvant of inactivated FMDV vaccine to explore their immune regulation roles. Methods: The mice in each group were subcutaneously injected with different vaccine formulations containing inactivated FMDV antigen adjuvanted with three doses (low, medium, and high) of AEAR or AEAR with ISA-206 adjuvant for 2 times respectively in 1 and 14 days. The variations of antibody level, lymphocyte count, and cytokine secretion in 14 to 42 days after first vaccination were monitored. Then cytotoxic T lymphocyte (CTL) response and antibody duration were measured after the second vaccination. Results: AEAR significantly induced FMDV-specific antibody titers and lymphocyte activation. AEAR at a medium dose stimulated Th1/Th2-type response through interleukin-4 and interferon-γ secreted by CD4⁺ T cells. Effective T lymphocyte counts were significantly elevated by AEAR. Importantly, the efficient CTL response was remarkably provoked by AEAR. Furthermore, AEAR at a low dose and ISA-206 adjuvant also synergistically promoted immune responses more significantly in immunized mice than those injected with only ISA-206 adjuvant and the stable antibody duration without body weight loss was 6 months. Conclusions: These findings suggested that AEAR had potential utility as a polysaccharide adjuvant for FMDV vaccines.

• Journal of Ocean Engineering and Technology
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• v.33 no.1
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• pp.33-41
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• 2019

Estimating fatigue damage is a very important issue in the design of ships. The springing and whipping response, which is the hydro-elastic response of the ship, can increase the fatigue damage of the ship. So, these phenomena should be considered in the design stage. However, the current studies on the the application of springing and whipping responses at the design stage are not sufficient. So, in this study, a prediction method was developed using fluid-structural interaction analysis to assess of the fatigue damage induced by springing and whipping. The stress transfer function (Stress RAO) was obtained by using the 3D FE model in the frequency domain, and the fatigue damage, including linear springing, was estimated by using the wide band damage model. We also used the 1D beam model to develop a method to estimate the fatigue damage, including nonlinear springing and whipping by the vertical bending moment in the short-term sea state. This method can be applied to structural members where fatigue strength is weak to vertical bending moments, such as longitudinal stiffeners. The methodology we developed was applied to 325K VLOC, and we analyzed the effect of the springing and whipping phenomena on the existing design.

• Earthquakes and Structures
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• v.23 no.2
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• pp.169-181
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• 2022

To research the dynamic response of the high-rise structure under the rocking ground motion, which we believed that the effect cannot be ignored, especially accompanied by vertical ground motion. Theoretical analysis and shaking table seismic simulation tests were used to study the response of a high-rise structure to excitation of a H-V-R ground motion that included horizontal, vertical, and rocking components. The use of a wavelet analysis filtering technique to extract the rocking component from data for the primary horizontal component in the first part, based on the principle of horizontal pendulum seismogram and the use of a wavelet analysis filtering technique. The dynamic equation of motion for a high-rise structure under H-V-R ground motion was developed in the second part, with extra P-△ effect due to ground rocking displacement was included in the external load excitation terms of the equation of motion, and the influence of the vertical component on the high-rise structure P-△ effect was also included. Shaking table tests were performed for H-V-R ground motion using a scale model of a high-rise TV tower structure in the third part, while the results of the shaking table tests and theoretical calculation were compared in the last part, and the following conclusions were made. The results of the shaking table test were consistent with the theoretical calculation results, which verified the accuracy of the theoretical analysis. The rocking component of ground motion significantly increased the displacement of the structure and caused an asymmetric displacement of the structure. Thus, the seismic design of an engineering structure should consider the additional P-△ effect due to the rocking component. Moreover, introducing the vertical component caused the geometric stiffness of the structure to change with time, and the influence of the rocking component on the structure was amplified due to this effect.

• Journal of Powder Materials
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• v.30 no.3
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• pp.203-209
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• 2023

Aluminum alloy-based additive manufacturing (AM) has emerged as a popular manufacturing process for the fabrication of complex parts in the automotive and aerospace industries. The addition of an inoculant to aluminum alloy powder has been demonstrated to effectively reduce cracking by promoting the formation of equiaxed grains. However, the optimization of the AM process parameters remains challenging owing to their variability. In this study, the response surface methodology (RSM) was used to predict the crack density of AM-processed Al alloy samples. RSM was performed by setting the process parameters and equiaxed grain ratio, which influence crack propagation, as independent variables and designating crack density as a response variable. The RSM-based quadratic polynomial models for crack-density prediction were found to be highly accurate. The relationship among the process parameters, crack density, and equiaxed grain fraction was also investigated using RSM. The findings of this study highlight the efficacy of RSM as a reliable approach for optimizing the properties of AM-processed parts with limited experimental data. These results can contribute to the development of robust AM processing strategies for the fabrication of high-quality Al alloy components for various applications.

• Wind and Structures
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• v.37 no.6
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• pp.399-412
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• 2023

Previous studies have shown that the integrated transfer function (ITF) is independent of turbulence characteristics and can be effectively applied to predict the buffeting response of elongated structures, assuming that the strip hypothesis is valid. However, existing research has not effectively identified the ITF through segment model vibration tests, and the influence of the 3D effect on the accuracy of the strip hypothesis and the characteristics of the ITF in wind tunnel tests has not been quantitatively studied. A segment model vibration measurement device that can change a test model's span-width ratio was designed in this study. An airfoil section and a streamlined box girder section structure were taken as the background, and their ITFs were effectively identified under different L/B (L denotes the turbulent integral scale and B denotes the structural width) and model span-width ratios. The influence laws of the 3D effect on the accuracy of the strip hypothesis and ITF identification in wind tunnel tests were systematically investigated. The results showed that L/B and the structural span-width ratio are two significant controlling factors that affect the accuracy of the strip hypothesis and ITF identification. The research provides an effective experimental method for accurately predicting the buffeting response of elongated structures based on ITFs identified through segment model vibration tests.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.965-969
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• 2003

In this paper, the implementation technique of digital crossover network using perfect linear phase IIR filters is presented. This system has various advantages which cannot be obtained from analog crossover network such as linear phase response, flat group delay and sharp cut-off at low-order over audio frequency band. The simulation results show that the group delay response is maximally flat and twice more attenuation in stop-band than the prototype elliptic IIR filter at all desired frequency.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.970-973
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• 2003

Abstract An idea to redce the direct-path short circuit current of the CMOS digital integrated circuit is present. The sample circuit model of the CMOS digital circuit is the CMOS current-control digital output driver circuit, which are also suitable for the low voltage supply integrated circuits as the simple digital inverter, are present in this title. The circuit consists of active MOS load as the current control source, which construct from the saturated n-channel and p-channel MOSFET and the general CMOS inverter circuits. The saturated MOSFET bias can control the output current and the frequency response of the circuit. The experimental results show that lower short circuit current control can make the lower frequency response of the circuit.