• Proceedings of the Korean Fiber Society Conference
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• 1996.04a
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• pp.202-206
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• 1996

• Proceedings of the Korean Fiber Society Conference
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• 2000.04a
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• pp.307-310
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• 2000

• Journal of Drive and Control
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• v.16 no.4
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• pp.65-73
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• 2019

In this study, flow analysis and fluid-solid interaction analysis were conducted on a hollow fiber membrane module used for analysis of dehumidification characteristics. To ensure the reliability of the flow analysis results, the dehumidification experiment was performed under the temperature of 30℃ and relative humidity of 30% RH. The results of the dehumidification experiments were compared with the flow analysis results. The results of dehumidification experiments and flow analysis had a difference of approximately 5%. A 1-Way fluid-solid interaction analysis with various materials was conducted. From the results, it was found that the baffle with the largest shape deformation (polyethylene material) was subjected to 2-way fluid-solid interaction. The analysis of fluid flow and dehumidification characteristics were analyzed according to the shape deformation of the baffle.

• Composites Research
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• v.16 no.2
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• pp.18-25
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• 2003

The tensile properties of short nylon6 fiber reinforced NR and SBR have been investigated as functions of fiber aspect ratio(AR), diameter ratio(DR), interphase condition, and fiber content. The tensile strength increased with increasing fiber AR(20 min.) and good interphase conditions. The short-fiber(DR=3 and AR=20 min.) reinforced SBR did not show the dilution effect for all interrhase conditions. And the short-fiber(DR=3 and AR=20min.) reinforced NR did not show the dilution effect except for the no-coating. The tensile moduli were significantly improved due to fiber AR. fiber content, and good interphase at same DR. The better interphase condition showed the higher pull-out force at same DR. Also, the stress analysis near the fiber end carried out using axisymmetric FEA to be convinced of the reinforcing mechanism. It is found that the fiber AR, interphase and DR have an important effect on tensile properties.

• Journal of Nutrition and Health
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• v.41 no.3
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• pp.264-282
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• 2008

The present study assessed the relation of dietary fiber to food habits in Korean adults aged 20 and over, using a newly established dietary fiber, as well as the 2001 Korean National Health and Nutrition Survey. The per capita average dietary fiber intake of Koreans was estimated to be 12.25 ${\pm}$ 5.23 g/1,000 kcal. Calorie-based dietary fiber intakes for females was over the KDRl, but for males it was below the KDRI. The levels of total dietary fiber and energy corresponded with frequent snacking but calorie-based dietary fiber intake did not. The subjects who skipped meals, frequently ate out and consumed fried foods tended to have lower levels of calorie-based dietary fiber although the levels of energy and total dietary fiber corresponded with frequent eating-out and consumption of fried foods. The results of this study suggest that Koreans must make efforts to regularly have three meals a day, reduce the frequency of eating out and consume fewer fried foods in order to maintain the optimum intake levels of dietary fiber that protect against chronic diseases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.694-699
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• 2005

The aim of this study was to develop muffins in which corn bran fiber was substituted 10, 30, 50 or $70\%$ for fat and the quality characteristics were compared with a full-fat counterpart. The volume and height of muffin was highest in control and decreased with increasing corn bran fiber content, but no difference in weight was observed (p<0.05). The incorporation of corn bran fiber in the product lowered lightness and redness values but decreased yellowness values. The mechanical texture parameters including hardness, springiness, gumminess and brittleness increased with increasing corn bran fiber levels. Scanning electron microscope showed that the size of air cells was decreased with increasing corn bran fiber levels. Sensory analysis yielded muffin with $30\%$ substitution of butter with corn bran fiber was considered to be as acceptable as control.

• Advances in concrete construction
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• v.8 no.1
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• pp.21-31
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• 2019

The rich recipe of ultra high performance concrete (UHPC) offers the higher mechanical, durability and dense microstructure property. The variable like cement/sand ratio, amount of supplementary cementitious material, water/binder ratio, amount of fiber etc. alters the UHPC hardened properties to any extent. Therefore, to understand the effects of these variables on the performance of UHPC, inevitably a stage-wise development is required. In the present experimental study, the effect of sand/cement ratio, the addition of finer material (fly ash and quartz powder) and, hybrid fiber on the fresh, compressive and microstructural property of UHPC is evaluated. The experiment is conducted in three phases; the first phase evaluates the flow value and strength attainment of ingredients, the second phase evaluates the efficiency of finer materials (fly ash and quartz powder) to develop the UHPC and the third phase evaluate the effect of hybrid fiber on the flow value and strength of ultra high performance hybrid fiber reinforced concrete (UHP-HFRC). It has been seen that the addition of fly ash improves the flow value and compressive strength of UHPC as compared to quartz powder. Further, the usage of hybrid fiber in fly ash contained matrix decreases the flow value and improves the strength of the UHP-HFRC matrix. The dense interface between matrix and fiber and, a higher amount of calcium silicate hydrate (CSH) in fly ash contained UHP-HFRC is revealed by SEM and XRD respectively. The dense interface (bond between the fiber and the UHPC matrix) and the higher CSH formation are the reason for the improvement in the compressive strength of fly ash based UHP-HFRC. The differential thermal analysis (DTA/TGA) shows the similar type of mass loss pattern, however, the amount of mass loss differs in fly ash and quartz powder contained UHP-HFRC.

• Advances in concrete construction
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• v.17 no.4
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• pp.233-243
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• 2024

The behavior of confined steel fiber-reinforced concrete (including confinement models) with compressive strengths ranging from normal to high strength is still rarely studied. This paper presents the results of an investigation of fifteen confined concrete cylinders containing steel fiber. The design parameters evaluated in the experiment included concrete compressive strength (covers normal to high strength), volume fraction of steel fiber and hoop spacing. The main objective of this study was to evaluate the behavior of confined steel fiber concrete by reviewing several design parameters, such as concrete strength (normal to high strength). It is then developed to be an analytical stress-strain expression for confined steel fiber concrete. The experimental program was carried out by making cylindrical specimens with a diameter of 100 mm and a height of 200 mm. The cylindrical test object is compressed in a monotonic uniaxial loading. Experimental results have shown steel fiber in concrete has an important role in increasing the compressive strength and strain of cylindrical concrete without steel fiber. In addition, the value of strength enhancement of confined concrete (K) along with increasing fiber fraction volume; which applies to normal to high-strength concrete. The value of K also increases if the compressive strength of the concrete tends to decrease and the spacing of the hoops is closer. The comparison of stress-strain behavior between the confined steel fiber concrete proposed by other researchers and the experimental results in general significantly different in post-peak response. The statistical analysis indicates that the value of Coefficient of Variation for the confinement model by Campione is the closest compared to other existing confinement models in predicting the values of K and Toughness Index. Furthermore, the analytic stress-strain expression of confined steel fiber concrete was developed by adopting and modifying several equations from the present models. The proposed analytical expression is then verified with the experimental results. The results of the verification show that the stress-strain behavior of confined steel fiber concrete is relatively close.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.9
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• pp.1284-1296
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• 2004

In order to investigate effects of anisotropic fiber packing on stresses in composites, a Volume Integral Equation Method is applied to calculate the elastostatic field in an unbounded isotropic elastic medium containing multiple orthotropic inclusions subject to remote loading, and a Mixed Volume and Boundary Integral Equation Method is introduced for the solution of elastostatic problems in unbounded isotropic materials containing multiple anisotropic inclusions as well as one void under uniform remote loading. A detailed analysis of stress fields at the interface between the isotropic matrix and the central orthotropic inclusion is carried out for square, hexagonal and random packing of orthotropic cylindrical inclusions, respectively. Also, an analysis of stress fields at the interface between the isotropic matrix and the central orthotropic inclusion is carried out, when it is assumed that a void is replaced with one inclusion adjacent to the central inclusion of square, hexagonal and random packing of orthotropic cylindrical inclusions, respectively, due to manufacturing and/or service induced defects. The effects of random orthotropic fiber packing on stresses at the interface between the isotropic matrix and the central orthotropic inclusion are compared with the influences of square and hexagonal orthotropic fiber packing on stresses. Through the analysis of plane elastostatic problems in unbounded isotropic matrix with multiple orthotropic inclusions and one void, it will be established that these new methods are very accurate and effective for investigating effects of general anisotropic fiber packing on stresses in composites.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.42-52
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• 2014

The aim of this investigation was to assess the relationship between food habits and nutrient intake in college female students. Nutrient intakes of 149 female subjects aged 19.3 y were determined by using 24-hr recall. The questionnaire included general characteristics and food habits (frequency of breakfast and fast food intake). Body composition was determined by bioim- pedance analysis. Nutrient analysis was performed with Can pro software. Statistics were generated using SAS 9.3 (SAS Institute, Cary, NC). Mean intake of energy, fiber, calcium, potassium. vitamin $B_2$ and vitamin C by the subjects ware below KDRIs. The nutrients for which the largest proportion of subjects showed inadequate intakes (less than the RI or AI) were potassium, calcium, vitamin C and fiber. Subjects that consumed fast food ${\leq}6$ times showed significantly lower intakes of calcium, potassium, fiber, vitamin A, vitamin $B_6$ and vitamin C. Subjects who skipped breakfast more frequently showed significantly lower intakes of energy, carbohydrate, fiber, calcium, iron, potassium, vitamin $B_2$ and vitamin C than subjects who ate breakfast more frequently. This is strong evidence that higher intakes of nutrients such as potassium, fiber, and calcium are associated with increased frequency of eating breakfast or decreased frequency of eating fast food. Low calcium, fiber, and potassium intakes may thus lead to chronic diseases. Nutrition education can be an important facilitator for improving nutrient intakes.