• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.5
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• pp.331-338
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• 2023

Modern bulletproof armor must be light and have excellent penetration resistance to ensure the mobility and safety of soldiers and military vehicles. The ballistic performance of heterogeneous structures of laminated flat plates as bulletproof armor depends on the arrangement of constituent materials for the same weight. In this study, we analyze bulletproof performance according to the stacking sequence of laminated bulletproof armor composed of Kevlar, ultra-high molecular weight polyethylene, and ethylene-vinyl-acetate foam. A ballistic analysis was performed by colliding a 7.62 × 51 mm NATO cartridge's M80 bullet at a speed of 856 m/s with six lamination arrangements with constituent materials thicknesses of 5 mm and 6.5 mm. To evaluate the bulletproof performance, the residual speed and residual energy of the projectile that penetrated the heterogeneous laminated flat plates were measured. Simulation results confirmed that the laminated structure with a stacking sequence of Kevlar, ultra-high molecular weight polyethylene, and ethylene-vinyl-acetate foam had the best bulletproof performance for the same weight.

• Journal of Gifted/Talented Education
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• v.18 no.3
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• pp.591-612
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• 2008

In order to investigate the composition and characteristics of instructional objectives in a teaching-learning material for gifted elementary students in science, 217 instructional objectives across 13 themes in 4 areas of 'energy','materials', 'life' and 'earth' were analyzed by Bloom's revised taxonomy of educational objectives. Four types of factual, conceptual, procedural and meta-cognitive knowledge in knowledge dimension were all comprised in the objectives. Conceptual knowledge was primary constituent of the objectives and the proportion of factual knowledge was the least. On the other hand, all 6 categories of 'remember', 'understand', 'apply', 'analyze', 'evaluate' and 'create' in cognitive process dimension were also comprised in the objectives. The category of 'understand' was primary constituent and that of 'remember' was the least one. While conceptual knowledge in knowledge dimension was primary constituent of the objectives in 'energy', 'materials' and 'earth' areas, procedural knowledge was the most objectives in 'life' area. The least type of knowledge was factual knowledge in all 4 areas. In cognitive process dimension, the category of 'understand' was primary constituent and that of 'remember' was the least one in all 4 areas. In conclusion, it was showed that the instructional objectives in the teaching-learning material reflected the characteristics of educational objectives for gifted students in science.

• Journal of Korean Medicine for Obesity Research
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• v.14 no.2
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• pp.72-79
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• 2014

The purpose of this study is analyzed of exploratory research potential as anti-obesity agents of Euiiin-tang. Four Korean databases and 2 Korean Journals (Riss4U, KISS, OASIS, DBPIA, and Journal of Korean Rehabilitation Medicine, Journal of Korean Medicine of Obesity Research) were searched using search word 'individual herbs' and 'obesity', 'weight loss', 'fat', 'hypertension', 'hyperlipidemia', 'diabetes'. Clinical and Experimental Research published in the journal were analyzed, review research, studies of pharmacopunctures and studies of mixed herbal medicine were excluded. We collected 23 studies. Seven studies of Coicis Semen, 10 stdies of Ephedra Herba, 2 study of Angelica gigas Nakai, 3 studies Atractylodis Rhizoma Alba, 1 studies of Glycyrrhiza inflata Batal. Most studies were experiment researches which were composed of in vivo or in vitro, and clinical trial was 5 studies of Ephedra Herba. Main constituent herb, Coicis Semen, Ephedra Herba were thought to represent an anti-obesity effect. Through the result, we can assume to be likely effect of Euiiin-tang as obesity medicine.

• School Mathematics
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• v.15 no.1
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• pp.15-35
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• 2013

The purpose of the research is to categorize math learners into pattern through those tools that distinguish math learning style for middle school students. On the ground of survey for 976 middle school students, the fact that there are 16 different math learning style at the result of cluster analysis is confirmed and the results are compared and analyzed previous research. Also according to the each constituent of math learning style, dissimilarity of distribution about learner of different sexes and grades are analyzed. It's helpful to understanding the whole characteristics of learners regarding math learning to figure out their cognitive and affective learning styles through the tools to distinguish their math learning styles.

• Structural Engineering and Mechanics
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• v.34 no.4
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• pp.525-539
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• 2010

Polymer matrix composites are widely used in many engineering applications as they can be customized to meet a desired performance while not only maintaining low cost but also reducing weight. Polymers can experience viscoelastic-viscoplastic response when subjected to external loadings. Various reinforcements and fillers are added to polymers which bring out more complexity in analyzing the timedependent response. This study formulates an integrated micromechanical model and finite element (FE) analysis for predicting effective viscoelastic-viscoplastic response of polymer based hybrid composites. The studied hybrid system consists of unidirectional short-fiber reinforcements and a matrix system which is composed of solid spherical particle fillers dispersed in a homogeneous polymer constituent. The goal is to predict effective performance of hybrid systems having different compositions and properties of the fiber, particle, and matrix constituents. A combined Schapery's viscoelastic integral model and Valanis's endochronic viscoplastic model is used for the polymer constituent. The particle and fiber constituents are assumed linear elastic. A previously developed micromechanical model of particle reinforced composite is first used to obtain effective mechanical properties of the matrix systems. The effective properties of the matrix are then integrated to a unit-cell model of short-fiber reinforced composites, which is generated using the FE. The effective properties of the matrix are implemented using a user material subroutine in the FE framework. Limited experimental data and analytical solutions available in the literatures are used for comparisons.

• Journal of Sasang Constitutional Medicine
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• v.3 no.1
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• pp.151-172
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• 1991

Comparative blood analysis was carried out to investigate the change of blood constituent in TAE-EUM-IN group and control group. RBC, WBC, hemoglobin, hematocrit, total protein, triglyceride, phospholipid, total cholesterol, LDL-cholesterol, HDL-cholesterol, BUN, creatinine, ACTH, cortisol and prostaglandin E and $F_2{\alpha}$ were measured. And the following results were obtained: 1. In the change of blood cell, the value of hematocrit showed significant difference, while that of RBC, WBC and himoglobin didn't. 2. In the change of protein, the value of total protein showed significant difference, but that of albumin didn't. 3. In the change of lipid and cholesterol in serum, the value of triglyceride, phospholipid, total cholesterol and LDL-cholesterol indicated significant difference, while that of HDL-cholesterol indicated significant difference, while that of HDL-cholesterol didn't. 4. The value of BUN in serum represented significant difference, but that of creatinine didn't. 5. The value of cortisol in plasma showed significant difference, but that of ACTH didn't. 6. The value of prostaglandin E and $F_2{\alpha}$ in plasma showed significant difference. These results suggest that investigation on hormones and blood constituents enables objectification in differentiation of four types of physical constitution.

• Advanced Composite Materials
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• v.17 no.4
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• pp.373-407
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• 2008

This paper will examine the possibilities of the virtual tests of composite structures by simulating mechanical behaviors by using supercomputing technologies, which have now become easily available and powerful but relatively inexpensive. We will describe mainly the applications of large-scale finite element analysis using the direct numerical simulation (DNS), which describes composite material properties considering individual constituent properties. DNS approach is based on the full microscopic concepts, which can provide detailed information about the local interaction between the constituents and micro-failure mechanisms by separate modeling of each constituent. Various composite materials such as metal matrix composites (MMCs), active fiber composites (AFCs), boron/epoxy cross-ply laminates and 3-D orthogonal woven composites are selected as verification examples of DNS. The effective elastic moduli and impact structural characteristics of the composites are determined using the DNS models. These DNS models can also give the global and local information about deformations and influences of high local in-plane and interlaminar stresses induced by transverse impact loading at a microscopic level inside the materials. Furthermore, the multi-scale models based on DNS concepts considering microscopic and macroscopic structures simultaneously are also developed and a numerical low-velocity impact simulation is performed using these multi-scale DNS models. Through these various applications of DNS models, it can be shown that the DNS approach can provide insights of various structural behaviors of composite structures.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.216-217
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• 2007

In this study, we analyzed the electrical loss characteristics between ribbon and output terminal of constituent material according to electrical resistance during interconnection process of PV module. From this result, the electrical output power reduction rate caused by interaction between ribbon and cell's interconnection was 2.88%. There was 1W electrical output power reduction through the 16 solar cells. So it is expected that the wider size of PV module gives the higher loss in electricity production. Also, the average output power of PV module passed lamination process was increased by 0.081W per one solar cell and the increase rate was 3.7%.PV module's electrical loss before and after lamination process according to constituent material's terminal was 0.49W and 0.50W, respectively.

• Cross-Cultural Studies
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• v.52
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• pp.393-416
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• 2018

Negative Stripping Construction in English involves the disjunction but, the adverb not, and a constituent NP. This construction is an incomplete sentence although it delivers a complete sentential meaning. Interpretation of this construction may be ambiguous in that the constituent NP can either be construed as the subject, or as the complements including the object. To generate such sentences and resolve the issue of ambiguity, we propose a construction-based analysis under direct interpretation approach, rejecting previous analyses based on deletion approaches. In so doing, we suggest a negative stripping construction rule that can account for ambiguous meaning. This rule further can enable us to explain syntactic structures and readings of Negative Stripping Construction.

• Applied Microscopy
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• v.52
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• pp.3.1-3.8
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• 2022

Our purpose in this study is to analyze the microstructural characteristics and constituent elements of inorganic substances added to the yellow ink and red ink pigments used in permanent makeup. We observed the microstructural properties of inorganic pigments added to the ink using a scanning electron microscopy (SEM) and analyzed the constituent elements of the inorganic pigment particles using an energy dispersive X-ray spectroscopy (EDX). In red wine-colored ink, cubic titanium dioxide with a diameter of 110 to 200 nm was the major component, and rod-shaped iron oxide was rarely observed. Most of the ingredients of taupe yellow ink were rod-shaped yellow iron oxide, and a small amount of cubic titanium dioxide was observed. Red wine-colored ink and taupe yellow ink contained lumps composed of titanium dioxide particles. In red wine-colored ink, lumps were formed by agglomeration. However, we observed that the surface of the lump composed of titanium dioxide in the taupe yellow ink had a smooth surface caused by external physical compression. The titanium dioxide particle mass which found in taupe yellow ink in this study is an artificial product. When this mass accumulates in the dermis, it may cause a color mismatch. Therefore, permanent makeup using fine pigments should be free of foreign substances that may cause trouble in the skin. In addition, there is a need to improve the quality of the ink so that the required color can be safe and long lasting in the dermis.