• Composites Research
• /
• 제36권3호
• /
• pp.173-179
• /
• 2023

The sandwich structure, consisting of a core and a face sheet, is used for lightweight structural application. Generally, cellular structures like honeycomb, foam, and lattice structures are utilized for the core. Among these, lattice structures have several advantages over other types of structures. In other studies, curved lattice structures were reported to have higher mechanical properties than straight structures by converting shear stresses acting on the structure into compressive stresses. Moreover, the addition of vertical struts can have a positive effect on the mechanical properties of the lattice structure. For the purpose, two lattice structures with Circle Arch (CC) and Circular Arch with a vertical column (CC_C) were studied, which were fabricated by using selective laser sintering was conducted. The result showed that CC_C has dramatic performance improvements in specific strength, modulus, and strain energy density compared to CC, confirming that vertical struts played a significant role in the lattice core. Finite element analysis was employed to determine the cause of the stress behavior of CC and CC_C. This study is expected to help design structurally superior lattice cores and sandwich structures.

• 한국산학기술학회논문지
• /
• 제4권4호
• /
• pp.357-360
• /
• 2003

작약의 methanol 추출물은 혈소판 활성 실험에서 혈소판 응집에 대해 강한 억제를 보였다. 활성성분은 chromatography방법을 사용하여 정제하였고 NMR과 기존의 Data로 분석하였다. Compound 1b는 benzoyloxypaeoniflorin과 동일한 구조임을 확인하였으며. compound 2e는 작약의 주성분인 paeoniflorin과 동일한 화학구조를 가졌으며 , compound 3a의 분석결과 구조적 유사성은 있으나 동일한 구조식은 확인 할 수 없었지만 collagen에서 응집억제활성이 90％이상의 뛰어난 활성을 나타내어 benzoyloxypaeoniflorin과 유사하게 benzoyl 기가 다른 작용기로 치환되었거나 Rl group이 다른 작용기로 치환된 형태로 추측하였다. Paeoniflorin이 collagen보다 thrombin에서 강한 억제를 보이는 것은 Ca/sup 2＋/ chelate를 형성함으로 인해 calcium 대사산물이 파괴된 것으로 추측했다. Compound 3a는 paeoniflorin의 benzoyl 기에 있는 OH기나 paeoniflorin의 glycoside 5-carbon위치의 OH기 대신에 다른 작용기가 대사산물로의 역할을 수행했을 것으로 추정했다.

• 대한가정학회지
• /
• 제26권4호
• /
• pp.129-160
• /
• 1988

The purpose of the present study is to understand the change in the relation between mother-in-law and daughter-in-law according to the social change in comparison with the survey effects in 1974 (ko Jung-Ja) and 1985 to find out the cause of conflict in both side of power structure and affection structure, indicating behavior, the influences on the relationships among family, possible meditators. this thesis was made by an experimental research. Data were collected from 146 mothers-in-law and 141 daughters-in-law in Pusan. The collected data were analysed by statistical methods such is as follows, 1. cause of conflict In power structure the cause of conflict is, in the case of mother-in-law opinion opposion and shaughty attitude by daughter in-low and, in the case of daughter-in-law, domestic dominance. It is thought that there is a difference of viw\ew between mother-in-law and daughter-in-law about the possesion of economic dominance and many conflicts rises because of economic dominance. but the study in 1985 than 1974 suggests the possibility of conflict meditator because mother-in-law and daughter-in-law do homework dependently in the practice of power. In affection structure, the chief dissatisfaction toward daughter-in-law showes the change in time. In 1974, there was no affection and respect. In 1985, the rate of doing without consultation was high. Also, the lack of communication of mother-in-law and daughter-in-law is the cause of conflict. 2. Indicating behavior the rate of thinking alone if high in both sides. But in the survey of 1985, the covert verbal aggressive action with which mother-in-law appeals to her daughter and daughter-in-law to husband is rising. 3. Influence on the relationship among family by the conflict between mother-in-law and daughter-in-law. the conflict between mother-in-law and daughter-in-law play negative effects on the intimacy and relation between husband and wife. 4. Conflict mediation behavior As compremiser, it is suggested that in the case of daughter-in-law the position and role of husband is important and, in the case of mother-in-law respects mother-in-law, daughter-in-law and gives her the role.

• 사회복지연구
• /
• 제36호
• /
• pp.129-149
• /
• 2008

본 연구는 청소년 성역할 고정관념의 성 차이를 알아보고 이에 영향을 미치는 변인들을 가족특성과 청소년 개인특성을 중심으로 규명하기 위하여 실시되었다. 이를 위해 한국청소년정책연구원이 2005년 조사한 초등 2차 패널 자료와 중등 3차 패널 자료를 사용하였으며 분석결과는 다음과 같다. 첫째, 성역할 고정관념은 여학생보다 남학생이 더 유효하게 높았다. 둘째, 남성성 성역할 고정관념은 남학생 뿐 아니라 여학생에게도 여성성 성역할 고정관념보다 높은 수준으로 유지되고 있었다. 셋째, 남학생의 자존감은 성역할 고정관념에 유의한 정적인 영향을 미치는 것으로 나타났지만 여학생의 자존감은 성역할 고정관념과 무관하였다. 넷째, 여학생 집단에서 아버지와 어머니의 교육수준, 가족형태는 성역할 고정관념의 유의한 감소를 가져오는 것으로 나타났지만, 남학생 집단의 경우 어머니의 교육수준만 남성성 성역할 고정관념의 유의한 증가를 가져오는 것으로 나타나 여학생은 가족의 영향을 남학생보다 더 많이 받고 있었으며, 효과에 있어서도 성역할 고정관념의 완화를 경험하고 있었으나 남학생은 그 반대인 것으로 나타났다. 이러한 결과를 토대로 청소년의 균형 있는 성역할 태도 형성을 위한 제언을 제시하였다.

• 충청수학회지
• /
• 제8권1호
• /
• pp.137-145
• /
• 1995

In the white noise analysis the one-parameter groups play the powerful role. In this report, we will see a subgroup of infinite dimensional unitary group $U_{\infty}$ including guage transform and structure of this subgroup under the view point of Lie algebra.

• Korean Journal of Mathematics
• /
• 제10권2호
• /
• pp.131-140
• /
• 2002

This paper is devoted to the study of the role of fuzzy proximity spaces. We define a fuzzy K-proximity space, a fuzzy R-proximity space and prove some of its properties. Furthermore, we discuss the topological structure based on these fuzzy K-proximity and fuzzy R-proximity.

• Korean Journal of Mathematics
• /
• 제28권4호
• /
• pp.973-984
• /
• 2020

This paper is devoted to study the reproducing property on 2-inner product Hilbert spaces. We focus on a new structure to produce reproducing kernel Hilbert and Banach spaces. According to multi variable computing, this structures play the key role in probability, mathematical finance and machine learning.

• 산경연구논집
• /
• 제10권2호
• /
• pp.7-15
• /
• 2019

Purpose - The industrial structure upgrading can play an important role in promoting the carbon emission efficiency. Thus, this paper attempts to study the impact of industrial structure upgrading on carbon emission efficiency in order to reduce carbon emissions. Research design, data, and methodology - This paper selects panel data of 30 provinces and municipalities (autonomous regions) in China from 2001 to 2016, and divides them into three regions. The Moore index is used to measure the industrial structure upgrading, the non-radial SBM model based on undesired output is used to measure the slack variable to calculate the total factor carbon emission efficiency. Finally the impact of industrial structure upgrading on the carbon emission efficiency are analyzed. Results - It is found that the Moore index and the carbon emission efficiency in the eastern region is the highest in the three regions. Conclusions - The influence of various influencing factors on carbon emission efficiency is different between regions. The Moore index has a positive effect on the carbon emission efficiency in the eastern region, and has a negative influence coefficient on the central region. The effect on the western region is not obvious.

• 천문학회보
• /
• 제41권2호
• /
• pp.41.3-42
• /
• 2016

No matter how intense magnetic flux it contains, a coronal magnetic structure has little free magnetic energy when a composing magnetic field is close to a potential field, or current-free field where no volume electric current flows. What kind of electric current system is developed is therefore a key to evaluating the activity of a coronal magnetic structure. Since the corona is a highly conductive medium, a coronal electric current tends to survive without being dissipated, so the free magnetic energy provided by a coronal electric current is normally hard to release in the corona. This work aims at clarifying how a coronal electric current system is structurally developed into a system responsible for producing a flare. Toward this end, we perform diffusive MHD simulations for the emergence of a magnetic flux tube with different twist applied to it, and go through the process of structuring a coronal electric current in a twisted flux tube emerging to form a coronal magnetic structure. Interestingly, when a strongly twisted flux tube emerges, there spontaneously forms a structure inside the flux tube, where a coronal electric current changes flow pattern from field-aligned dominant to cross-field dominant. We demonstrate that this structure plays a key role in releasing free magnetic energy via rapid dissipation of a coronal electric current, thereby producing a flare.

• Advances in nano research
• /
• 제9권4호
• /
• pp.237-250
• /
• 2020

An accurate plate theory for assessing sandwich structures is of interest in order to provide precise results. Hence, this paper develops Layer-Wise (LW) theory for reaching precise results in terms of buckling and vibration behavior of Functionally Graded Carbon Nanotube-Reinforced Composite (FG-CNTRC) annular nanoplates. Furthermore, for simulating the structure much more realistic, its edges are elastically restrained against in-plane and transverse displacement. The nano structure is integrated with piezoelectric layers. Four distributions of Single-Walled Carbon Nanotubes (SWCNTs) along the thickness direction of the core layer are investigated. The Differential Quadrature Method (DQM) is utilized to solve the motion equations of nano structure subjected to the electric field. The influence of various parameters is depicted on both critical buckling load and frequency of the structure. The accuracy of solution procedure is demonstrated by comparing results with classical edge conditions. The results ascertain that the effects of different distributions of CNTs and their volume fraction are significant on the behavior of the system. Furthermore, the amount of in-plane and transverse spring coefficients plays an important role in the buckling and vibration behavior of the nano-structure and optimization of nano-structure design.