• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.213-214
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• 2006

The results of investigations in screw design for metall injection molding (MIM) will be presented. The consistency of cavity pressure, metering time and MFQ (monitoring of feedstock quality; parameter measured during metering) was chosen to compare different screws. A simulation program was used to optimize the conveying and melting mechanisms in the plastification unit. The theoretical background of this simulation programm will be explained.

• 센서학회지
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• 제10권1호
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• pp.71-79
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• 2001

The use of a glass-plate probe of rectangular shape is proposed for the measurement of transmission loss in optical waveguides. The light-collecting window is of a thin, rectangular shape and is perpendicular to the light streak, while the conventional fiberglass probe has a small circular face. This transversely elongated form results in a grate improvement of mechanical tolerance for the probe movement in the vortical as well as in the transverse direction. A theoretical investigation also presents a reasonable agreement with the experiments.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.882-887
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• 2001

This paper deals with the effect of mass-spring-mass resonance that is a characteristics of the multi-layered panels in order to enhance sound insulation performance. From theoretical and experimental investigation, it is evident that tuning mass-spring-mass resonance by controlling elastic modulus of the core materials is very important to improve the STC value without increasing the weight of panels, resulting in enhancing STC value more than 10 dB.

• Bulletin of the Korean Chemical Society
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• 제11권6호
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• pp.511-515
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• 1990

Ab initio calculations with MP3 and CISD method were performed for the FCO and $FCO^+$. The equilibrium geometry of FCO shows the reasonable agreement with experimental values. $FCO^+$ has a linear geometry with $R_{CF}=1.213\;and\;R_{CO}=1.118{\AA}$. The quadratic force constants of $FCO^+$ are 23.21 md ${\AA}^{-1}$ for CO stretch and 12.38 md ${\AA}^{-1}$ for CF stretch. The cubic force constants and the other molecular constants are also calculated.

• Bulletin of the Korean Chemical Society
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• 제7권4호
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• pp.283-288
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• 1986

A nonlinear analysis is presented for the treatment of fluctuations near the critical point in the presence of diffusion in the Schlogl models. The two time scaling method is used to obtain an evolution equation for the amplitude of fluctuations. It is shown that the fluctuations decay to zero in the stable region and they are enhanced to a finite value as time goes to infinity in the unstable region.

• Asia Marketing Journal
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• 제2권2호
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• pp.39-62
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• 2000

많은 소비자 행동은 목표 지향적 행동으로 볼 수 있다. 이처럼 목표가 소비행동에서 차지하는 비중이 높다보니 최근 들어 목표자체에 대한 연구와, 목표의 추구와 성취에 있어 태도의 역할에 대한 연구에 상당한 관심이 집중되고 있다. 그런데 지금까지의 태도연구는 주로 이성적인 행동에 그 초점이 맞추어져 왔으며 그 대표적 모델은 Fishbein과 Ajzen의 이성적 행동이론이다. 이성적 행동이론이 소비행동을 설명하는데 많은 기여를 했으나 목표지향적 행동을 설명하는데는 어느 정도 한계가 있다고 지적된다. 이 논문에서는 이성적 행동과 목표지향적 행동과의 차이점들을 살펴보고 목표지향적 행동을 설명하는 새로운 연구모형으로서 시도이론을 소개하였다. 또한 시도이론에 대한 실증 분석의 결과들을 제시하고 있다.

• Journal of Electrical Engineering and information Science
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• 제1권2호
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• pp.52-57
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• 1996

Detection of arcing high impedance faults has been a perplexing in the power distribution protection. Transient analysis of distribution disturbances for fault discrimination from other normal events is important for a secure protection of the power system. A simple parameter of wave form distortion quantification is used to analyze the behaviors of arcing faults and normal distribution disturbances. Theoretical perspectives of the transients were studied and actual disturbances were examined. From this investigation, a discrimination guideline based on the revised crest factor is developed. The discrimination method has a high potential to enhance the reliability and security for the distribution system protection.

• 전기화학회지
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• 제16권3호
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• pp.169-176
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• 2013

현재 이차전지에서 사용중인 양극활물질은 구조 안정성이 높은 층상구조(Layered Structure)의 리튬 금속 산화물(Solid State Lithium Oxide Compounds)이 주로 사용된다. 최근에는 리튬이차전지의 성능향상을 위해서 음극활물질과 전해질 사이의 계면뿐만 아니라, 양극활물질과 전해질 사이의 계면에 관한 연구가 활발히 진행되고 있으며, 이러한 계면의 연구를 위해서는 음극활물질 뿐만 아니라, 양극활물질의 표면에 관한 연구도 선행적으로 이루어져야 하는 상황이다. 대표적인 리튬금속 산화물질인 니켈산리튬($LiNiO_2$)과 코발트산리튬($LiCoO_2$)은 서로 매우 유사한 구조를 갖는 층상구조의 양극활물질이다. 코발트산리튬이 다양한 실험적, 이론적 연구가 진행된 반면에, 니켈산 리튬은 실험적 연구에 비해서 이론적 연구가 부족하다. 따라서, 본 연구에서는 니켈산리튬의 X-선 회절계 측정 결과(XRD data)에 나오는9개의 표면 방향을 범밀도함수이론(Density Functional Theory)을 이용하여 니켈산리튬 표면의 표면 에너지를 계산하였다. 니켈산리튬의 X-선 회절계 측정 결과(XRD data)에서는 (003), (104), (101), (110) 결정 등등이 순차적으로 주요하게 존재하는 것으로 확인되었다. 그러나 시뮬레이션을 이용한 각각의 표면 에너지 계산 결과, X-선 회절계 측정 결과와 다른 순서로 안정한 표면 에너지가 나타나는 결과를 얻었다. 따라서 에너지적으로 안정한 표면이자, X-선 회절계에서 주요하게 나타나는 (104)와 (101) 방향의 니켈산리튬 표면이 많이 노출되어 Li 이온의 충방전시 리튬의 삽입 탈리에 영향을 줄 것으로 예상된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 가을 학술발표회 논문집
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• pp.271-278
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• 1999

Soil filters are commonly used to protect the soil structures from eroding and piping. When filters are clogged by fine particles which are progressively accumulated, these may lead to buildup of excessive pore pressures also leading to instability in subsurface infrastructure. A filter in the backfill of a retaining wall, a filter adjacent to the lining of a tunnel, or a filter in the bottom of an earth dam can be clogged by transported fine particles. This causes reduction in the permeability, which in turn may lead to intolerable decreases in their drainage capacity. In this thesis, the extent of this reduction is addressed using results from both experimental and theoretical investigations. In the experimental phase, the permeability reduction of a filter is monitored when an influent of constant concentration flows into the filter (uncoupled test), and when the water flow through the soil-filter system to simulate an in-situ condition (coupled test), respectively. The results of coupled and uncoupled test are compared with among others. In the theoretical phase of the investigation, a representative elemental volume of the soil filter was modeled as an ensemble of capillary tubes and the permeability reduction due to physical clogging was simulated using basic principles of flow in cylindrical tubes. In general, it was found that the permeability was reduced by at least one order of magnitude, and that the results from the uncoupled test and theoretical investigations were in good agreement. It is observed that the amount of deposited particles of the coupled test matches fairly well with that of the uncoupled test, which indicates that the prediction of permeability reduction is possible by preforming the uncoupled test instead of the coupled test, and/or by utilizing the theoretical model.

• 보건교육건강증진학회지
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• 제20권3호
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• pp.145-170
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• 2003

The purpose of this study was to clarity the concept of health insensitivity using Hybrid model, which consists of three phases： theoretical, empirical, and analytic. In the theoretical phase, the definitions of health insensitivity were searched in korean dictionary and examples used in the websites because the concept of health insensitivity has never been studied before. Two dimensions of health insensitivity emerged out from this investigation were cognitive and behavioral. And then a working definition of health insensitivity was established. The sub-concepts and related factors of health insensitivity were identified through the extensive reviews of the literature focusing on two dimensions of cognitive and behavioral. In the empirical phase, in order to obtain description of health insensitivity, face-to-face in-depth interviews were conducted with nine persons who are not related to professional health care. Grounded theory approach was applied to analyze these qualitative data. In the final analytic phase, theoretical results and empirical results were analyzed in the integrated way and a theoretical framework of health insensitivity was established. A refined definition of health insensitivity was that decreased health risk perception in cognitive dimension and conduction of the unhealthy behaviors in behavioral dimension. Sub-concepts of decreased health risk perception were optimistic bias and decreased general fear. Sub-concepts of unhealthy behavior were doing health threatening behavior and not doing desirable health behavior. The contact of health information was a causal condition of health insensitivity. Optimistic disposition, health locus of control, and avoidance coping style were intervening conditions of health insensitivity. Three types of health insensitivity were identified： unconcern or ignorance type, optimistic bias type, and cognitive dissonance type. Finally, The implications of these findings for further research and nursing practice are discussed.