• Journal of Power Electronics
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• v.15 no.1
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• pp.190-201
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• 2015

This paper uses the switching function approach to present a simple state model of the Vienna-type rectifier. The approach introduces the relationship between the DC-link neutral point voltage and the AC side phase currents. A novel direct power control (DPC) strategy, which is based on the sliding mode control (SMC) for Vienna I rectifiers, is developed using the proposed power model in the stationary ${\alpha}-{\beta}$ reference frames. The SMC-based DPC methodology directly regulates instantaneous active and reactive powers without transforming to a synchronous rotating coordinate reference frame or a tracking phase angle of grid voltage. Moreover, the required rectifier control voltages are directly calculated by utilizing the non-linear SMC scheme. Theoretically, active and reactive power flows are controlled without ripple or cross coupling. Furthermore, the fixed-switching frequency is obtained by employing the simplified space vector modulation (SVM). SVM solves the complicated designing problem of the AC harmonic filter. The simplified SVM is based on the simplification of the space vector diagram of a three-level converter into that of a two-level converter. The dwelling time calculation and switching sequence selection are easily implemented like those in the conventional two-level rectifier. Replacing the current control loops with power control loops simplifies the system design and enhances the transient performance. The simulation models in MATLAB/Simulink and the digital signal processor-controlled 1.5 kW Vienna-type rectifier are used to verify the fast responses and robustness of the proposed control scheme.

• Journal of the Korean Chemical Society
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• v.37 no.8
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• pp.773-778
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• 1993

Poly(vinyl chloride)(PVC) membrane electrodes based on the lipophilic neutral carrier, dibenzo-18-crown-6(DB18C6) and benzo-15-crown-5 (B15C5) as the active sensors for Tl$^+$ ion have been prepared and tested in different content of the potassium tetrakis(4-chlorophenyl)borate (KTClPB) as lipophilic salt. Dioctyl adipate (DOA), 2-nitrophenyl phenyl ether (NPPE) and o-nitrophenyl actyl ether (NPOE) were used as plasticizing solvent mediators. Electrodes exhibited good linear responses of 40∼55 mV decade$^{-1}$ for Tl$^+$ ion within the concentration ranges 10$^{-1}$∼10$^{-5}$M TlNO$_3$. Selectivity coefficients of interfering ions (alkali metal, alkaline earth metal and some transition metal ions) for Tl$^+$-ISE were determined by separate solution method and were sufficiently small for most of them. These crown ether type ion-selective electrodes are suitable for use with aqueous solution at pH > 3.

• Animal Bioscience
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• v.34 no.3_spc
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• pp.463-470
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• 2021

Objective: This experiment was conducted to find out the immunological effects of wheat phytase when long-chain inorganic polyphosphate (polyP) treated with wheat phytase was added to a macrophage cell line, Raw 264.7, when compared to intact long-chain polyP. Methods: Nitric oxide (NO) production of Raw 264.7 cells exposed to P700, a long-chain polyP with an average of 1,150 phosphate residues, treated with or without wheat phytase, was measured by Griess method. Phagocytosis assay of P700 treated with or without phytase in Raw 264.7 cells was investigated using neutral red uptake. The secretion of tumor necrosis factor α (TNF-α) by Raw 264.7 cells with wheat phytase-treated P700 compared to intact P700 was observed by using Mouse TNF-α enzyme-linked immunosorbent assay kit. Results: P700 treated with wheat phytase effectively increased NO production of Raw 264.7 cells by 172% when compared with intact P700 at 12 h exposure. At 5 mM of P700 concentration, wheat phytase promoted NO production of macrophages most strongly. P700, treated with wheat phytase, stimulated phagocytosis in macrophages at 12 h exposure by about 1.7-fold compared to intact P700. In addition, P700 treated with wheat phytase effectively increased in vitro phagocytic activity of Raw 264.7 cells at a concentration above 5 mM when compared to intact P700. P700 dephosphorylated by wheat phytase increased the release of TNF-α from Raw 264.7 cells by 143% over that from intact P700 after 6 h exposure. At the concentration of 50 μM P700, wheat phytase increased the secretion of cytokine, TNF-α, by 124% over that from intact P700. Conclusion: In animal husbandry, wheat phytase can mitigate the long-chain polyP causing damage by improving the immune capabilities of macrophages in the host. Thus, wheat phytase has potential as an immunological modulator and future feed additive for regulating immune responses caused by inflammation induced by long-chain polyP from bacterial infection.

• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.3
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• pp.168-176
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• 2023

Silicon (Si) has the potential to improve plant growth and stress tolerance. The study aimed to explore Si-involving plant responses and molecular characterization of different Si-responsive genes in alfalfa. In this study, the exogenous supplementation of Si enhanced plant growth, and biomass yield. Si-acquisition in alfalfa root and shoot was higher in Si-supplemented compared to silicon deficient (-Si) plants, implying Si-acquisition has beneficial on alfalfa plants. As a consequence, the quantum efficiency of photosystem II (Fv/Fm) was significantly increased in silicon-sufficient (+Si) plants. The quantitative gene expression analysis exhibited a significant upregulation of the Lsi1, Lsi2, Lsi3, NIP5;1, and NIP6;1 genes in alfalfa roots, while BOR1, BOR4, NIP2, and NIP3 showed no significant variation in their expression. The MEME results further noticed the association of four motifs related to the major intrinsic protein (MIP). The interaction analysis revealed that NIP5;1 and Lsi1 showed a shared gene network with NIP2, BOR1, and BOR4, and Lsi2, Lsi3 and NIP3-1, respectively. These results suggest that members of the major intrinsic proteins (MIPs) family especially Lsi1, Lsi2, Lsi3, NIP5;1, and NIP6;1 genes helped to pass water and other neutral solutes through the cell membrane and those played significant roles in Si uptake and transport in plants. Together, these insights might be useful for alfalfa breeding and genome editing approaches for alfalfa improvement.

• Journal of Environmental Science International
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• v.33 no.1
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• pp.9-16
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• 2024

This study analyzed a survey of residents' awareness of rivers and water spaces that reflected residents' awareness in order to establish a basic park green space plan. Through this, the perception and requirements of rivers and water spaces were analyzed and important information was provided for urban planning and environmental management. As a result of analyzing residents' neutral satisfaction with rivers and their opinions on the frequency of use, role, and purpose, it was confirmed that rivers are recognized as an important part of urban life and contain the potential for development for a better urban environment. . However, considering the dissatisfied response and the relatively low frequency of use, we came to the conclusion that better urban planning and management is needed to meet the needs of residents by improving the river environment and providing various facilities. Based on this, city managers should focus on river management and improvement by actively collecting residents' opinions. Through analysis of the causes of dissatisfied responses, measures such as improving the environment around rivers and waste management should be prepared, and a broad strategy for environmental conservation and utilization should be established by reflecting the diverse expectations and demands of residents. These ongoing efforts are expected to have a positive impact on the sustainability of the city and improvement of residents' quality of life. Additionally, the results of this study will be able to contribute to establishing policies for urban planning and environmental improvement through similar research and analysis in other regions.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.2
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• pp.100-107
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• 2018

The material and geometrical nonlinear finite elment analysis of UHPFRC 50M composite box girder was carried out. Constitute law in tension and compressive region of UHPFRC and HPC were modeled based on specimen test. The accuracy of nonlinear FEM analysis was verified by the experimental result of UHPFRC 50M composite girder. The UHPFRC 50M segmental composite box girder which has 1.5% steel fiber of volume fraction, 135MPa compressive strength and 18MPa tensile strength was tested. The post-tensioned UHPFRC composite girder consisted of three segment UHPFRC U-girder and High Strength Concrete reinforced slab. The parts of UHPFRC girder were modeled by 8nodes hexahedron elements and reinforcement bars and tendons were built by 2nodes linear elements by Midas FEA software. The constitutive laws of concrete materials were selected Multi-linear model both of tension and compression function under total strain crack model, which was included in classifying of smeared crack model. The nonlinearity of reinforcement elements and tendon was simulated by Von Mises criteria. The nonlinear static analysis was applied by incremental-iteration method with convergence criteria of Newton-Raphson. The validation of numerical analysis was verified by comparison with experimental result and numerical analysis result of load-deflection response, neutral axis coordinate change, and cracking pattern of girder. The load-deflection response was fitted very well with comparison to the experimental result. The finite element analysis is seen to satisfactorily predict flexural behavioral responses of post-tensioned, reinforced UHPFRC composite box girder.

• The Journal of the Korea Contents Association
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• v.14 no.5
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• pp.224-234
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• 2014

This study designed to nursing student's image of professional nurse before clinical practice using Q-methodology. Using Q-methodology, 43 nursing student sorted 34 statements selected professional nurse type. The statement positions on the sorting continuum were scored from +4(representing the highest level of agreement) through 0(at the neutral position on the continuum) through -4(representing the highest level of disagreement). Factor analysis of the data was undertaken using PC QUANL software to determine if any patterns were discernible. The three factors extracted eigenvalues greater than 1.0 and explained approximately 53.94% of the variation in responses(41.63, 7.41 and 4.9% respectively). The categories were labeled 'Nightingale's nursing philosophy type', 'Consideration of patient type' and 'Self-development type'. Twenty-two students who located to factor 1 "Nightingale's nursing philosophy type". Eleven students who located to factor 2 "Consideration of patient type". Three students sho located to the factor 3 "Self-development type". The significant differences found in the subjective structure of nursing student's image of professional nurse. The study results can be utilized in both an effective nursing education and clinical practice.

• Science of Emotion and Sensibility
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• v.21 no.3
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• pp.49-60
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• 2018

Trait anger is one of the psychological traits associated with experiences of anger. Individuals with high trait anger become angry easily at trivial events, and experience anger more frequently, intensely, and over a longer duration. This study aimed to investigate neural responses during experiences of anger, and identify the neural correlates of trait anger. Thirty five adults participated in the functional magnetic resonance (fMRI) experiment. They were scanned while they recalled an anger-inducing memory that was supposed to evoke an experience of anger. During the angry recall compared to the emotionally neutral recall, our participants showed greater neural activation in the right superior temporal gyrus (BA38), left inferior frontal gyrus (BA45), right thalamus, right insula (BA13), bilateral cuneus (BA17), and right cerebellum anterior lobe. The correlation analysis revealed that trait anger scores were positively associated with right insula activity during the angry recall. Individuals with higher trait anger were more likely to show greater activity in the right insula in response to past experiences of anger, as previously implicated in various studies of emotional processing. This finding suggests that trait anger may be an important factor in modulating anger-related brain activity.

• Journal of agricultural medicine and community health
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• v.21 no.2
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• pp.221-230
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• 1996

This study was purposed to develop the fluoride mouthrinsing project through the public health system in a rural area. This project was performed under the management of the public health dentist for the 3rd grade students selected from the 5 primary schools at Goksunggun in Chonnam area. Fluoride mouthrinsing was executed with 0.2% neutral sodium fluoride solution once a week. After 1 year's fluoride mouthrinsing project, DMFT index, DMF rate frequencies of toothbrushing, simplified oral hygiene index, and the responses to fluoride mouthrinsing project of the school children participated were examined. The results obtained from this study were as follows: 1. The fluoride mouthrinsing project for school children was performed average 10 times a year by the public health dentist. They were relatively little active to perform this project. 2. There was no significant difference in the increasement of DMFT index and DMF rate during 1 year between control and fluoride mouthrinsing group. 3. Control group was increased higher than fluoride mouthrinsing group in simplified oral hygiene index. 4. Toothbrushing frequencies increased in both groups. 5. 80.4% of school children participated in fluoride mouthrinsing project was responded to like it, and 78.2% among them was responded the project to be beneficial for their dental health. 6. 39.2% of school children was responded to have water-like taste for fluoride solution. But 34.0% of them was done to have strange taste. On consideration of above findings, this fluoride mouthrinsing project was not well performed by the public health dentists and also the oral health status of school children participated was not significantly improved by this project. Therefore, to perform continually this project well, it was recommended that this project should be performed by other person such as dental hygienist rather than public health dentist.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1585-1592
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• 2016

The present experiment was conducted to evaluate the effect of simulated heat stress on digestibility and methane ($CH_4$) emission. Four non-lactating crossbred cattle were exposed to $25^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$, and $40^{\circ}C$ temperature with a relative humidity of 40% to 50% in a climatic chamber from 10:00 hours to 15:00 hours every day for 27 days. The physiological responses were recorded at 15:00 hours every day. The blood samples were collected at 15:00 hours on 1st, 6th, 11th, 16th, and 21st days and serum was collected for biochemical analysis. After 21 days, fecal and feed samples were collected continuously for six days for the estimation of digestibility. In the last 48 hours gas samples were collected continuously to estimate $CH_4$ emission. Heat stress in experimental animals at $35^{\circ}C$ and $40^{\circ}C$ was evident from an alteration (p<0.05) in rectal temperature, respiratory rate, pulse rate, water intake and serum thyroxin levels. The serum lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase activity and protein, urea, creatinine and triglyceride concentration changed (p<0.05), and body weight of the animals decreased (p<0.05) after temperature exposure at $40^{\circ}C$. The dry matter intake (DMI) was lower (p<0.05) at $40^{\circ}C$ exposure. The dry matter and neutral detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ compared to $25^{\circ}C$ and $30^{\circ}C$ exposure whereas, organic matter (OM) and acid detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ than $40^{\circ}C$ thermal exposure. The $CH_4$ emission/kg DMI and organic matter intake (OMI) declined (p<0.05) with increase in exposure temperature and reached its lowest levels at $40^{\circ}C$. It can be concluded from the present study that the digestibility and $CH_4$ emission were affected by intensity of heat stress. Further studies are necessary with respect to ruminal microbial changes to justify the variation in the digestibility and $CH_4$ emission during differential heat stress.