Daejeon, South Korea
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Lee B.Y.,Chonnam National University | Han B.-C.,Woosong Information College | Cho C.-G.,Chosun University | Kim Y.Y.,Chungnam National University
Computers and Concrete | Year: 2012

This paper presents the mix composition and production method that was applied to an extruded Ductile Fiber Reinforced Cement Composite (DFRCC) panel, as well as the flexural performance, represented by deformation hardening behavior with multiple cracking. The effect of fiber distribution characteristics on the flexural behavior of the panel is also addressed. In order to demonstrate the fiber distribution effect, a series of experiments and analyses, including a sectional image analysis and micromechanical analysis, was performed. From the experimental and analysis results, it was found that the flexural behavior of the panel was highly affected by a slight variation in the mix composition. In terms of the average fiber orientation, the fiber distribution was found to be similar to that derived under the assumption of a two-dimensional random distribution, irrespective of the mix composition. In contrast, the probability density function for the fiber orientation was measured to vary depending on the mix composition. Copyright © 2012 Techno Press.

Kim Y.Y.,Chungnam National University | Lee B.Y.,Chonnam National University | Bang J.-W.,Chungnam National University | Han B.-C.,Woosong Information College | And 2 more authors.
Composites Part B: Engineering | Year: 2014

The cracking and strength improvement in beams are one of main issues in the area of architecture and civil engineering. This paper presents the experimental and numerically predictive studies on the flexural performance of reinforced concrete (RC) beams strengthened with a strain-hardening cementitious composite (SHCC) and high strength reinforcing steel bar (HSRS bar) as a new strengthening method for beams. In order to investigate the effects of SHCC and HSRS bar on the control of cracking and load bearing capacity, four types of beam specimens were manufactured and a series of flexural bending tests were performed. The test results showed that the crack width can be controlled by applying SHCC and the load-bearing capacity of beams improved by applying the SHCC and HSRS bar. © 2013 Elsevier Ltd. All rights reserved.

Cho C.-G.,Chosun University | Lee B.Y.,Chonnam National University | Kim Y.Y.,Chungnam National University | Han B.-C.,Woosong Information College | Lee S.-J.,Chosun University
Advances in Materials Science and Engineering | Year: 2012

This paper presents a new reinforced concrete (RC) composite slab system by applying an extruded Ductile Fiber Reinforced Cement Composite (DFRCC) panel. In the proposed composite slab system, the DFRCC panel, which has ribs to allow for complete composite action, is manufactured by extrusion process; then, the longitudinal and transverse reinforcements, both at the bottom and the top, are placed, and finally the topping concrete is placed. In order to investigate the flexural behavior of the proposed composite slab system, a series of bending tests was performed. From the test results, it was found that the extruded DFRCC panel has good deformation-hardening behavior under flexural loading conditions and that the developed composite slab system, applied with an extruded DFRCC panel, exhibits higher flexural performance compared to conventional RC slab system in terms of the stiffness, load-bearing capacity, ductility, and cracking control. Copyright © 2012 Chang-Geun Cho et al.

Lee D.-W.,Kyungnam University | You D.-H.,Kyungnam University | Yang E.-K.,Kyungnam University | Jang I.-C.,Kyungnam University | And 4 more authors.
Journal of the Korean Society of Food Science and Nutrition | Year: 2010

The antioxidant and angiotensin converting enzyme (ACE) inhibitory harvesting times were evaluated. During February and July of 2008, Styela clava were harvested once per month, and divided into flesh and tunic parts. Each collected part was extracted with water and 70% ethanol. DPPH radical scavenging activity (RSA) for flesh part was higher than that of tunic part, and water extract of flesh harvested at April showed the highest value (53.02% at 10 mg/mL). The highest ABTS RSA was found at water extract of flesh part harvested atMarch. Water extracts of flesh parts harvested from March to May showed relatively higher ACE inhibitory activity, and freezing did not affect ACE inhibitory activity. The results indicated that antioxidant and ACE inhibitory activity of S. clava were variable depending on harvesting time and parts.

Jo J.-E.,Chungnam National University | Yook H.-S.,Chungnam National University | Kim K.-H.,Chungnam National University | Baek J.-Y.,Chungnam National University | And 3 more authors.
Journal of the Korean Society of Food Science and Nutrition | Year: 2010

This study was carried out to examine the changes of the quality feature and antioxidant activity of grape by-products. This experiment was to arrange the basic data for developing a functional material using grape by-products which were useless resources. Hot-air and freeze drying were followed by the gamma irradiation of 1~20 kGy. Hunter's color value, in case of hot-air drying, showed the highest L and a value in the 3 kGy, and it decreased according to the increase of the exposure dose. In the case of freeze drying it showed the highest L and b value at the highest exposure, 20 kGy. It was considered that the breakdown of the pigment through high temperature processing was launched and the influence according to the gamma irradiation was not shown. The gamma irradiation of 3 kGy appeared to have a good influence on the color of the grape by-products which went through hot-air drying. The contents of the total phenolic compounds, in case of hot-air drying, showed the highest total polyphenol contents in the 3 kGy irradiation and it decreased according to the increase of the exposure dose; in contrast, the higher phenolic contents showed in the irradiated group than in the control. In case of freeze drying, the highest phenolic contents appeared in the control but 3 kGy showed the highest one in the irradiated group. Results of radical scavenging activity using DPPH and ABTS indicated that 3 kGy showed the highest radical scavenging activity in hot-air and freeze drying. Therefore, it was found that gamma irradiation of 3 kGy could improve the color and antioxidant activity of grape by-products, but an antioxidant activity of grape by-product due to the gamma irradiation was a little affected in the aspects of by-product utilization.

Wang Z.,Chungnam National University | Wang C.Y.,Chungnam National University | Yang Z.H.,Zhejiang University | Fang Z.M.,Chungnam National University | And 4 more authors.
Biocontrol Science and Technology | Year: 2011

Esteya vermicola, as the first reported endoparasitic fungus of pinewood nematode (PWN), exhibited high infectivity in vitro and has been patented based on its potential as a bio-control agent against PWN. The isolation substrates and taxonomic status suggested E. vermicola is associated with beetles, saprotrophic and kills nematodes in trees. However, the direct experimental evidence for this was still lacking. In the present studies, beta-tubulin gene was applied to confirm the taxonomic identification of E. vermicola. Furthermore, our results showed that E. vermicola survived resin and other chemicals secreted by pine trees, and reproduced with new lunate conidia to parasitize other migratory PWNs. In order to confirm the pathogenicity of E. vermicola, pine seedlings and large pine trees were inoculated with 300 μL and 40 mL conidia suspensions (109 mL-1). The results showed that all treated pine trees were healthy with no differences compared to the controls. Furthermore, necrosis or discoloration caused by this fungus was not observed on wood slices. Basal knowledge was provided for the application of E. vermicola to control PWN in vivo. © 2011 Taylor & Francis.

Background: plant extracts of Forsythia suspensa, which contain pinoresinol, have been proposed as an alternative to antibiotics due to their antioxidant, anti-inflammatory, and microflora modulating effects. Objective: to evaluate the effects of dietary F. suspensa on feed utilization, rumen fermentation, blood parameters and immune response of Korean native goats (Capra hircus). Methods: a total of nine Korean native goats were assigned to one of three dietary treatments: 1) a basal diet without F. suspensa, 2) a basal diet added with 0.25% F. suspensa, or 3) a basal diet added with 0.50% F. suspensa. A change-over design was used in three consecutive periods to give 9 replicates per treatment. Each period lasted 18 days, including 15 days of adaptation to feed and environmental conditions and three days of total collection of feces and urine. Rumen fluid and blood samples were also collected. Nutrient digestibility, nitrogen retention, ruminal content, and blood metabolites—including immunoglobulins—were measured. Results: F. suspensa supplementation had no effect on nutrient digestibility, whole body nitrogen retention rate, ruminal pH, acetate, propionate, isobutyrate, butyrate, isovalerate, or valerate content (p>0.05). However, F. suspensa supplementation decreased total volatile fatty acids (VFA) concentration compared with the control diet, regardless of F. suspensa concentrations (p<0.05). Goats fed a diet containing 0.25% F. suspensa had greater alkaline phosphatase (ALP) concentration than those fed a control or a diet with 0.50% F. suspensa (p<0.05). Feeding different concentrations of dietary F. suspensa did not influence plasma IgA and IgM levels (p>0.05), although goats receiving both 0.25% and 0.50% F. suspensa diets had greater plasma IgG than those fed the control diet (p<0.05). Conclusions: supplementation of 0.25% F. suspensa significantly decreased total VFA concentrations and increased plasma IgG in Korean native goats, compared with those fed the control diet. © 2015, Universidad de Antioquia. All rights Reserved.

Boo H.-O.,WELLPHYTO Co. | Kim H.-H.,Woosong Information College | Barasch D.,Hebrew University of Jerusalem | Nemirovski A.,Hebrew University of Jerusalem | And 3 more authors.
European Food Research and Technology | Year: 2016

Abstract: The effects of bioactivity, binding properties, anti-obesity and antioxidant enzyme activities in different fractions from the roots of Codonopsis lanceolata [C. lanceolata (CL)] in comparison with Nelumbo nucifera Gaertn. [N. nucifera Gaertn (NN)] were evaluated in vitro. The rate of cell survival progressively decreased in a dose-dependent manner. Butyl alcohol fraction of CL exhibited a pronounced cytotoxic effect (75.73 %) comparable to that of hexane (79.82 %), following by methylene chloride (84.02 %), ethyl acetate (87.62 %) and water fractions (86.30 %) at the same concentration at 200 μg/mL on 3T3-L1 cells. Confluent 3T3-L1 cells were treated with 50 µg/mL of CL and NN extracts and then stained with Oil Red O solution. Inhibitory degree of lipid accumulation against these extracts showed a significant level compared with the control sample. Both lipid accumulation and adipocyte differentiation showed relatively high effects in methyl chloride fraction. Comparative results of cytotoxicity and inhibitory degree of lipid accumulation were obtained with extracts of N. nucifera Gaertn. roots. The root extract of C. lanceolata had the significantly highest SOD enzyme activity of 84.5 % in ethyl acetate fraction and the lowest in water (57.9 %). Similar correlations were found for CAT, APX and POD activities as the highest in ethyl acetate partition layer compared with the other fractions. The binding properties were determined by interaction of polyphenols extracts of CL and NN with human serum albumin. Overall results of properties of these two plants suggest that the roots of C. lanceolata and N. nucifera Gaertn. may assist in the potential biological activity on anti-obesity, cytotoxic, antioxidant and binding capacities as a part of functional food.Graphical Abstract: CL, NN, Codonopsis lanceolata, Nelumbo nucifera Gaertn. I, II, Effects of solvent fractions on lipid accumulation in 3T3-L1 cells of CL, NN. Con, control; MC, methylene chloride fraction; III, IV, 3D-fluorescence spectra and corresponding contour maps (III, IV) of polyphenols of CL and NN in interaction with human serum albumin.[Figure not available: see fulltext.] © 2016 Springer-Verlag Berlin Heidelberg

PubMed | Woosong Information College, Hebrew University of Jerusalem, PHYTO M&F Co., Chungbuk National University and Korea Basic Science Institute
Type: | Journal: Plant foods for human nutrition (Dordrecht, Netherlands) | Year: 2016

Platycodon grandiflorum (PG), a species of herbaceous flowering perennial plant of the family Campanulaceae, has been used as a traditional oriental medicine for bronchitis, asthma, pulmonary tuberculosis, diabetes, hepatic fibrosis, bone disorders and many others similar diseases and as a food supplement. For the primary profiling of PG gas chromatography coupled with high resolution - time of flight mass spectrometry (GC/HR-TOF MS) was used as an analytical tool. A comparison of optimal extraction of metabolites was carried out with a number of solvents [hexane, methylene chloride, methanol, ethanol, methanol: ethanol (70:30, v:v)]. In extracts with methanol: ethanol (70:30 v:v) were detected higher amounts of metabolites than with other solvents. Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) plots showed significant differences between the diploid and tetraploid metabolite profiles. Extracts of tetraploid showed higher amounts of amino acids, while extracts of diploid contained more organic acids and sugars. Graphical Abstract .

Moon H.-I.,Kangwon National University | Kim H.Y.,Kangwon National University | Choi C.,Woosong Information College | Lee I.H.,Hankook ESI Co. | Kim D.H.,Hwaseung RandA Co.
Transactions of the Korean Society of Mechanical Engineers, A | Year: 2010

The performance of power window system was decided by driving characteristics of the window regulator part and reaction by the glass run. The performance of power window system usually has been predicted by experimental methods. In this paper, an analytical method using the explicit code was suggested to overcome the limit of the experimental methods. The friction coefficient of glass run was obtained by the friction test at various conditions and the Mooney-Rivlin model was used. Also, a mechanism of window regulator consisted of the fast belt system and the slip ring elements. And, we conducted the analysis considering characteristic of a motor and obtained the lifting speed of automotive glass with high reliability © 2010 The Korean Society of Mechanic Engineers.

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