• 한국전산구조공학회논문집
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• 제36권5호
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• pp.331-338
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• 2023

현대의 방탄 장갑은 우수한 관통 저항성을 갖추어야할 뿐만 아니라 군인과 군용차량의 기동성이 확보되어야 하기 때문에 경량화가 중요한 개발 요소가 되었다. 이종 적층 평판 구조의 방탄 장갑의 방탄 성능은 동일 중량 대비 구성 재료의 배열에 따라 달라진다. 본 논문에서는 케블라, 초고분자량 폴리에틸렌 그리고 에바 폼으로 구성된 방탄 장갑의 적층 배열에 따른 방탄 성능을 분석한다. 구성 재료의 두께가 5mm와 6.5mm인 두 가지 경우에서 6가지 적층 배열에 대하여 7.62 × 51mm NATO 탄환의 M80 탄을 856m/s의 속도로 충돌시키는 피탄 해석을 수행하였다. 방탄 성능을 평가하기 위해 이종 적층 평판을 관통한 발사체의 잔류 속도와 잔류 에너지를 측정하였다. 시뮬레이션 결과를 통해 케블라, 초고분자량 폴리에틸렌, 에바 폼의 배열 순서를 갖는 적층 구조가 동일 중량에 대해 가장 우수한 방탄 성능을 가짐을 확인하였다.

• 영재교육연구
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• 제18권3호
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• pp.591-612
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• 2008

본 연구에서 K 초등 과학 영재교육 자료에 제시된 수업목표를 Bloom의 신 교육목표 분류학으로 분석한 결과는 다음과 같다. 제시된 수업목표는 13개 주제에 총 217개였고 영역별로는 에너지 27개, 물질 68개, 생명 52개, 지구 70개였다. 지식차원에서는 개념적 지식에 해당하는 수업목표가 가장 많았고 절차적 지식, 메타인지 지식, 사실적 지식 순으로 나타났다. 인지과정 차원에서는 '이해하다'에 해당하는 수업목표가 가장 많았으며 '적용하다', '창안하다', '분석하다'와 '평가하다' 순이었고 '기억하다'는 매우 적었다. 수업목표를 에너지, 물질, 생명, 지구의 네 영역으로 나누어 분류한 결과 지식 차원에서는 에너지, 물질, 지구 분야의 경우 개념적 지식이 가장 높은 비율을 차지했고 절차적 지식, 메타인지 지식, 사실적 지식 순으로 나타났다. 반면, 생명 분야는 절차적 지식이 가장 높은 비율을 차지했고 다음으로 메타인지 지식, 개념적 지식, 사실적 지식 순으로 나타났다. 인지과정 차원에서는 네 영역 모두 '이해하다'에 해당하는 수업목표가 가장 많았는데 그 비율은 지구 영역에서 가장 높았으며 물질, 에너지, 생명 순으로 나타났다. '기억하다' 범주에 해당하는 수업목표는 네 영역 모두에서 낮게 나타났다. 따라서 K 초등 과학 영재교육 자료의 수업목표는 복잡한 지적 조작을 요구하는 상위 수준의 사고 기능을 기르는 데 목표를 두고 있음을 확인하였다.

• 한방비만학회지
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• 제14권2호
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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.

• 대한수학교육학회지:학교수학
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• 제15권1호
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• pp.15-35
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• 2013

본 연구의 목적은 중학생용 수학학습양식 판별도구를 개발하여 선호유형을 범주화하는 것이다. 개발된 수학학습양식 판별도구로 976명의 중학생을 대상으로 설문조사하여 16가지의 수학학습양식 유형이 존재하는지를 확인하였고 이를 선행 연구들과 비교 분석하였다. 또한 수학학습양식의 각 요인에 따른 양식별 남녀 학습자, 학년별 학습자의 분포에 어떠한 차이가 있는지 분석하였다. 수학학습양식 판별도구를 통해서 학습자의 인지적 정의적 학습양식을 파악함으로써 수학학습에 대한 학습자 특성을 전체적으로 파악하여 획일화된 수업형태에서 벗어나 개별화 수업으로 나아갈 수 있는 방향을 제시하고자 한다.

• Structural Engineering and Mechanics
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• 제34권4호
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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.

• 사상체질의학회지
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• 제3권1호
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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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• 제17권4호
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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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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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.

• 비교문화연구
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• 제52권
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• pp.393-416
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• 2018

영어의 부정 스트리핑 구문은 접속사 but, 부사 not, 그리고 하나의 구성성분 NP로 구성되어있다. 해당 구문은 통사적으로는 불완전한 문장처럼 보이지만 의미적으로는 완전한 해석을 전달하며 특히, 이 구문은 중의적인 해석을 가질 수도 있기 때문에 적절한 접근방법으로 의미부를 분석하는 것이 필수적이다. 본 논문에서는 부정 스트리핑 구문의 통사적 구문생성과 중의성 해소를 위해 직접 해석 접근법(Direct Interpretation Approach)을 기반으로 한 구문 규칙을 제안하고자 한다. 이 규칙은 이전의 연구들이 해결하지 못하는 문제점을 설명할 수 있으며, 통사, 의미, 화용론 등 다양한 특성을 설명해준다.

• Applied Microscopy
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• 제52권
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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.