• 대한전자공학회논문지TC
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• 제37권2호
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• pp.7-16
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• 2000

본 논문에서는 p-persistent CSMA 방식의 IEEE 802.11 MAC 계층 프로토콜을 모델링 하였다. 그리고 renewal 이론을 적용하여 수학적으로 분석한 Basic CSMA/CA 프로토콜, CTS/RTS 프로토콜 그리고 은닉 노드를 고려한 Basic CSMA/CA 등의 성능분석모델을 제안하였다. 제안한 분석 모델을 이용하여 throughput을 구한 결과, active 노드 수가 적거나 패킷의 길이가 짧을 때는 Basic CSMA/CA 프로토콜 방식이, active 노드 수가 많거나 패킷의 길이가 길 때는 CTS/RTS 프로토콜 방식이 우수하였다. 또한 active 노드 수가 적은 경우가 많은 경우 보다 은닉 노드의 영향을 적게 받았다.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2576-2581
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• 2021

The thermal stability and crystallization behaviors of La₂O₃ containing B₂O₃-CaO-Al₂O₃ glass waste forms were investigated to evaluate the stability of waste form during emergencies in deep geological disposal. For glasses containing 15% La₂O₃, LaBO₃ phases were observed as major crystals from 780 ℃ and exhibited needlelike structures. Al, Ca, and O were homogeneously distributed throughout the entire specimen, while some portions of B and La were concentrated in some parts. By differential thermal analysis at various heating rates, the activation energy for grain growth and the crystallization rate of LaBO₃ were calculated to be 12.6 kJ/mol and 199.5 kJ/mol, respectively. These values are comparable to other waste forms being developed for the same purpose.

• 한국정보통신학회논문지
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• 제6권8호
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• pp.1206-1215
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• 2002

최근 무선 인터넷 시장이 급속히 성장함에 따라 다양한 무선 인터넷 컨텐츠 개발에 대한 수요가 급증하고 있다. 또한 다양한 인터넷 단말기와 플랫폼을 유연하게 지원할 수 있는 확장성이 추가된 XHTML이 세계적인 표준 마크업 언어로 자리잡고 있다 이러한 XHTML은 HTML4에 XML 1.0을 적용시켜 재정의 함으로써, 기존의 유무선 인터넷 컨텐츠 통합과 상호 운용성의 증진을 위한 핵심 기술로 인식되고 있다. 이에 본 논문에서는 XHTML을 기반으로 한 무선 인터넷 언어인 XHTML Basic 문서를 편집 할 수 있는 문서 편집기를 설계하고 구현한다. 구현한 무선 인터넷 문서 편집기는 XHTML Basic 문서를 원하는 형태로 표현 가능하도록 CSS 생성 기능을 제공하고, 문서를 쉽게 작성할 수 있도록 WYSIWYG 방식의 편집을 지원한다.

• Journal of Information Processing Systems
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• 제16권1호
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• pp.120-131
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• 2020

In order to solve the problem of point clouds coordinate conversion of non-directional scanners, this paper proposes a basic Rodrigues rotation method. Specifically, we convert the 6 degree-of-freedom (6-DOF) rotation and translation matrix into the uniaxial rotation matrix, and establish the equation of objective vector conversion based on the basic Rodrigues rotation scheme. We demonstrate the applicability of the new method by using a bar-shaped emboss point clouds as experimental input, the three-axis error and three-term error as validate indicators. The results suggest that the new method does not need linearization and is suitable for optional rotation angle. Meanwhile, the new method achieves the seamless splicing of point clouds. Furthermore, the coordinate conversion scheme proposed in this paper performs superiority by comparing with the iterative closest point (ICP) conversion method. Therefore, the basic Rodrigues rotation method is not only regarded as a suitable tool to achieve the conversion of point clouds, but also provides certain reference and guidance for similar projects.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1056-1058
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• 2005

Electrical and optical characteristics of MEH-PPV-based PLEDs with the LiF anode interfacial layer were investigated. The maximum luminance efficiency of the device with a LiF anode interfacial layer of 1-nm-thick was 3.0 lm/W, which is higher than 1.97 lm/W of the device without a LiF layer. By inserting LiF, excess injected holes from ITO anode can be blocked and hence the recombination ratio of electrons and holes can be increased in the emitting layer to improve device efficiency.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.1071-1076
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• 2003

Basic creep of concrete during very early ages is an important factor on the behavior of young concrete and a great deal of research has been executed. However, in recent studies, it was revealed that the basic creep measured by sealed concrete was inaccurate, especially for high strength concrete because of autogenous shrinkage at early age. This paper presents the results from experimental study that investigate to explore the effect of autogenous shrinkage in basic creep. More specifically, four different mix proportions were casted and the primary variables were water-cement ratios. Through this research, it was found that the differences between apparent specific creep and real specific creep were remarkable in low water-cement ratio at early age. Therefore, it is recommended to modify existing creep model by considering autogenous shrinkage

• 공업화학
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• 제18권1호
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• pp.54-57
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• 2007

Octachlorocyclotetraphosphazene을 사용하여 cyclotetraphosphazene 구조를 내부에 갖고 외부로 8개의 사슬 구조를 갖는 cyclotetraphosphazene 유도체를 합성하였다. 그리고 이 유도체와 콜레스테롤을 사용하여 vesicle을 형성시켰으며, TEM을 이용해서 이 vesicle의 형태를 살펴보고, encapsulation 효율 등을 알아보았다. 이 vesicle의 안정도는 dihexadecylphosphate를 첨가함에 의해서 크게 향상되었다.

• 산업경영시스템학회지
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• 제28권3호
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• pp.10-17
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• 2005

In this paper, the life cycle assessment(LCA) methodology is applied to Personal Computer's basic materials in order to analyze the impact to the environment. LCA data collection is carried out taking into account on main materials of PC's parts and component. And the impact assessment is the environmental burden on three factor into air emission(CO2, SOx, NOx), five factor into water emission(BOD, COD, SS, N, P), and three factor on transported substance(cl, NH4, SO4). According to the result, the environmental burden of PC's basic materials was proved to be used total energy 6,285Mj and emitted CO2 259.8kg, SOx 3,571g, NOx 330g, COD 1,328g, P 246g, N 2,434g. And this paper was presented the problems of its disposition-incinerating, landfill, and recycling.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2023년도 추계학술발표대회
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• pp.64-65
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• 2023

이 논문은 한글 프로그래밍 언어 KoBASIC의 설계 및 구현에 관해 기술한다. 현대 사회에서 프로그래밍은 핵심 기술로 자리 잡았으며, 프로그래밍 언어는 이를 실현하기 위한 도구이다. 그러나 대다수의 프로그래밍 언어는 영어로 구성되어 있어, 한글을 주로 사용하는 사용자들에게는 접근이 어려움을 겪고 있다. 이에 본 연구는 한글 사용자들도 쉽게 접근하고 이해할 수 있는 프로그래밍 환경을 제공하기 위한 목적으로, 전통적인 교육용 프로그래밍 언어인 BASIC을 기반으로 한글 프로그래밍 언어 KoBASIC을 새롭게 제안한다.

• Wind and Structures
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• 제37권2호
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• pp.117-131
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• 2023

Korea Design Standard (KDS) will be updated with two major revisions on the assessment of wind load and performance-based wind design (PBWD). Major changes on the wind load assessment are the wind load factor and basic wind speed. Wind load factor in KDS is reduced from 1.3 to 1, and mean recurrence interval (MRI) for basic wind speed increases from 100 years to 500 years considering the reduction of wind load factor. Additional modification is made including pressure coefficient, torsional moment coefficient and spectrum, and aeroelastic instability. Combined effect of the updates of KDS code on the assessment of wind load is discussed with the case study on the specified sites and building. PBWD is newly added in KDS code to consider the cases with various target performance, vortex-induced vibration, aeroelastic instability, or inelastic behavior. Proposed methods and target performance for PBWD in KDS code are introduced.