• Steel and Composite Structures
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• v.35 no.4
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• pp.463-474
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• 2020

In this paper, the influence of adding multi-walled carbon nanotube (MWCNT) on the pull behavior of steel and GFRP bars in ultra-high-performance concrete (UHPC) was examined experimentally and numerically. For numerical analysis, 3D nonlinear finite element modeling (FEM) with the help of ABAQUS software was used. Mechanical properties of the specimens, including Young's modulus, tensile strength and compressive strength, were extracted from the experimental results of the tests performed on standard cube specimens and for different values of weight percent of MWCNTs. In order to consider more realistic assumptions, the bond between concrete and bar was simulated using adhesive surfaces and Cohesive Zone Model (CZM), whose parameters were obtained by calibrating the results of the finite element model with the experimental results of pullout tests. The accuracy of the results of the finite element model was proved with conducting the pullout experimental test which showed high accuracy of the proposed model. Then, the effect of different parameters such as the material of bar, the diameter of the bar, as well as the weight percent of MWCNT on the bond behavior of bar and UHPC were studied. The results suggest that modifying UHPC with MWCNT improves bond strength between concrete and bar. In MWCNT per 0.01 and 0.3 wt% of MWCNT, the maximum pullout strength of steel bar with a diameter of 16 mm increased by 52.5% and 58.7% compared to the control specimen (UHPC without nanoparticle). Also, this increase in GFRP bars with a diameter of 16 mm was 34.3% and 45%.

• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.281-286
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• 1995

In order to get basic information for utilization of yong leabes of medicinal herbs as vegetable, 7 species leaves of medicinal herbs were analyzed. The moisture content in 6 species leaves were 79.74 to 85.97%. The raw protein content were about 2% except Angelica gigas (1.12%) and Peucedanum japonica (1.27%). The raw fat were 0.96 to 1.36%, the raw fiber were 1.8 to 3.9% and the raw ash were 1.58 to 2.79%. There content of medicinal herbs were similar to general vegetables. The K contents were the highest among the medical components in all samples. The total contents of amino acid in Aralza elata was 965mg%, Scutellaria baicalensis 930mg%, Aralia cordata 879mg%, Angelica acutiloba 851mg%, Agastache rugosa 747mg%, and Peucedanum japonica 615mg%, Aspartic acid and glutamic acid in amino acid were generally the highest but methionine and cystine the lowest.

• Membrane Journal
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• v.20 no.4
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• pp.267-277
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• 2010

Gas separation membranes have been developed for decades in various areas to replace the conventional processes. Membrane processes for gas separation have many advantages of energy saving, compact size, and easy scale-up. Nowadays, gas separation processes is widely spreaded in nitrogen generating system, hydrogen generating system, membrane dryer, on board inert gas generating system, natural gas purification, biogas purification and fuel cells. Carbon dioxide separation process using membrane would be a strong candidate of carbon dioxide capturing process. In order to broaden the scope of application of gas separation membranes, development of new materials which can overcome the borderline of Robeson's plot should be necessary, so that many researchers and companies are trying to develop the new materials like polymers containing cardo and spiro group and PIMs (polymers for intrinsic microporosity).

• Korean Journal of Human Ecology
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• v.21 no.4
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• pp.791-803
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• 2012

This study intends to identify applicability of natural dye extracted from Aplysia kurodai, aiming to standardization of Aplysia kurodai natural dyeing through scientific validation by analyzing characteristics of pigment elements to review dyeability, colorfastness and antibacterial activity. Such material as silk fabrics that is animal fiber were used for this purpose, and derived following summarized results. UV/VIS spectrum analysis on the pigment of Aplysia kurodai that was extracted from purple gland showed that maximum absorbtion was near 540 nm. The silk fabric optimal dyeing can be achieved at a temperature of $55^{\circ}C$ with a colorant concentration of 5%. Dyed at $55^{\circ}C$ with interval of 10~90 minutes for identifying dye uptake over time to observed slow increase of dye uptake over time, and equilibrium occurred at 50 minutes. For dye uptake according to pH, while dye uptake was superior in acidity, it decreased rapidly in a base after pH 7. For color changes according to pH variation, it was reddish purple in acidity and was purplish red in a base. For color changes according to mordanting method, more clear color change had been obtained when process with aluminium pre-mordanting than non-mordanting and post-mordanting. The colorfastness to light, perspiration and washing was 1, 4~5, and 3~4 ratings respectively. The silk fabric dyed with Aplysia kurodai demonstrated excellent antimicrobial activity to Staphylococcus aureus and Klebsiella pneumoniae. The Aplysia kurodai can be used as a new colorant for the natural dyeing of silk.

• Journal of Biomedical Engineering Research
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• v.39 no.4
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• pp.168-174
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• 2018

Adipocytes affect obesity through the regulation of lipid metabolism. Physical loading is an important regulator of fat tissue. There are ongoing in vitro studies inducing mechanotransduction on 3T3-L1 preadipocytes with mechanical stimulus in order to treat obesity by inhibiting adipogenesis and provoking cell death. In this study, our goal was to suggest a new therapy for obesity by investigating whether fluid shear stress (FSS) changes transcription factors on 3T3-L1 related with adipogenesis and cell death. FSS loading was applied to 3T3-L1 preadipocytes at 1Pa and 1Hz. After loading, bright field images were taken and an immunofluorescence assay was conducted to observe actin stress fiber formation. Western blot analysis was conducted to identify the activation of the ERK pathway as well as the adipogenic factors, which including C/EBPs and $PPAR{\gamma}$. The expression of osteopontin, a protein related to inflammation in adipose tissue, and cell death related factors, Bax, Bcl-2, and Beclin, were also measured. Results showed that FSS stimulated the formation of actin stress fibers in 3T3-L1 and also that the activation of C/EBPs decreased significantly when compared with the control group. $PPAR{\gamma}$ activation in the 2 hour FSS group was lower than the 1 hour FSS group, which implied that the results were time dependent. Additionally, there were no differences in the expression of cell death factors after FSS loading. In summary, similar to other fibroblasts, the formation of actin stress fibers induced by mechanotransduction may affect the differentiation of 3T3-L1, leading to inhibition of adipogenesis and inflammation.

• Journal of Satellite, Information and Communications
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• v.2 no.1
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• pp.14-20
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• 2007

The Korean Military Satellite Communication System (KMILSATCOM) is composed of military payload of KOREASAT 5 and military satellite terminals. The military satellite terminals communicate with each other in satellite service area. The satellite terminal management system is developed for centralized management of satellite terminals and communications link. The satellite terminal management system dose not use terrestrial networks (i.e. Fiber optic, Microwave) for management because the KMILSATCOM is system for emergency (i.e. war time) and the satellite terminals has to move to operational area, so the management link must use satellite link. The management link is composed of 1 to N communication scheme for one manager and multiple terminals. This paper describes the satellite terminal management protocol architecture and the performance of the protocol of the KMILSATCOM system.

• Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.47-57
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• 2014

Thai Jasmine rice (Oryza sativa, long grain Indica var.) is popular in southeastern Asia and China due to its non-glutinous, fluffy texture and fragrant smell. However it has a high starch digestibility, which leads to an increased glycemic index (GI). Therefore it may require modified cooking methods for diabetes patients. The objectives of this study were to optimize the ratio of Thai Jasmine rice, sea tangle, and olive oil (CLTR) based on consumers' acceptance. The GI of plain cooked Thai Jasmine rice (CLR) was measured as a control. Sensory evaluation and response surface methodology were used to determine the optimal ratio. Texture analysis and nutritional evaluation were also performed on the optimal recipe of cooked Jasmine rice with sea tangle. A multiple regression equation was developed in quadratic canonical polynomial models. We used 26 trained Chinese panelists in their forties to rate color, flavor, adhesiveness, and glossiness, which we determined were highly correlated with overall acceptability. The optimal CLTR formula was 34.8% rice, 2.8% sea tangle, 61.9% water, and 0.5% olive oil. Compared to CLR, CLTR had a lower hardness, but a higher springiness and cohesiveness. However, CLR and CLTR had the same adhesiveness and chewiness. The addition of sea tangle and olive oil delayed retro-gradation of starch in CLTR and increased total dietary fiber, and protein and ash contents. The degree of gelatinization, and in vitro protein and starch digestibility of CLTR were lower than those of CLR. Based on Wolver' method, the GI of CLTR (52.9, incremental area under the glycemic-response curve, ignoring the area below fasting, as used for calculating the GI [Inc]) was lower compared with that of CLR (70.94, Inc), which indicates that CLTR is effective in decreasing and stabilizing blood glucose level, owing to its lower degree of gelatinization and starch digestibility. Our results show that CLTR can contribute to the development of a healthier meal for families and the fast food industry.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.3
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• pp.1-10
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• 2012

In spite of high resistant to corrosion and its strength, over the last two decades, concerns still remain about the durability of FRP materials under severe environmental and thermal exposures. In this paper, authors experimentally examine the combined degradation by thermal and chemical attacks in heterogeneous FRP rebar be made up with various fibers and resins. Five types of Carbon, Glass and Hybrid FRP rebars had manufactured by different process and surface patterns are adopted for the experiments such as weight change, interlaminar shear strength, SEM and FT-IR analysis. FRP specimens were immersed in alkaline or distilled solution up to 150 days and then thermal exposed on 60, 100, 150 and $300^{\circ}C$ for 30 minutes. From the test results, the degradation of FRP bars are influnced by the resin type and manufacturing process as well as the fiber, and ILSS of exposed FRP bar in solutions is slightly increased in initial stage and then decresed with the passing of immersed time. But, in this test, it is observed that the discrepancy of ILSS between degraded by alkaline solution and distilled water is negligible value.

• Journal of the Microelectronics and Packaging Society
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• v.20 no.1
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• pp.21-26
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• 2013

This study presents new analysis method to predict bending behavior of packaging substrate structure by comparing finite element method simulation and measured curvature using 3D scanner. Packaging substrate is easily bent and deflected while undergoing various processes such as curing of prepreg and copper pattern plating. We prepare specimens with various conditions and measure contours of each specimen and compute the residual stresses on deposited films using analytical solution to find the principle of bending. Core and prepreg in packaging substrate are made up of resin and bundles of fiber which exist orthogonally each other. Anisotropic material properties cause peculiar bending behavior of packaging substrate. We simulate the bending deflection with finite element method and verify the simulated deflection with measured data. The plating stress of electrodeposited copper is about 58 MPa. The curing stresses of solder resist and prepreg are about 13 MPa and 6.4 MPa respectively in room temperature.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.5
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• pp.500-511
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• 2017

This study was conducted to investigate the anthropometric data, bone density, serum profiles, nutrient intakes and diet quality of premenopausal and postmenopausal women. For the study, we obtained data for analysis from the combined 2008~2011 Korean National Health and Nutrition Examination Survey (KNHANES). The height and weight were 157.8 cm and 58.7 kg in premenopausal women and 155.5 cm and 58.3 kg in postmenopausal women, respectively. The obesity rate was 27.49% in premenopausal women and 34.98% in postmenopausal women (p<0.001). Total cholesterol, LDL-cholesterol, triglyceride, GOT, GPT and alkaline phosphatase in postmenopausal women were significantly higher than those in premenopausal women (p<0.001). The prevalence of osteoporosis was 0.0~0.89% in premenopausal women and 0.48~13.22% in postmenopausal women (p<0.001). In postmenopausal women, rates of hypertension, stroke, myocardial infarction, depression, and diabetes were significantly higher than those in premenopausal women. Water, fat. ash, sodium, retinol, thiamin, riboflavin and niacin intakes in premenopausal women were significantly higher than those in postmenopausal women. Water, fiber, Ca, and, K intakes were below KDRIs (Dietary Reference Intakes for Koreans) in both groups. The mean adequacy ratio (MAR) of premenopausal women was higher than that of postmenopausal women (p<0.001). The index of nutritional quality (INQ) in premenopausal women was also higher than that of postmenopausal women except iron and vitamin C. Therefore dietary guidelines and an education program should be developed for desirable improvement of health, bone density, nutrient status and dietary quality of postmenopausal women.