• 융합정보논문지
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• 제9권9호
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• pp.13-19
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• 2019

본 논문은 미국 정부가 추진하고 있는 커넥티드 차량에서 SCMS와 파일롯 정책에 대해 분석하였다. SCMS는 인증, 무결성, 프라이버시, 그리고 상호운용성을 보장한다. 미국의 SCMS 지원위원회는 국가단위의 SCMS를 설립하고 시스템 전반에 대한 통제 역할을 수행하고 있다. 물론 보안 정책 수립 그리고 절차와 훈련 프로그램을 도입한다. 본 논문에서는 C-ITS에 적용하는 SCMS의 필요성에 대해 논의하였다. 그리고 SCMS의 구조에 대해 분석하였고 미국 정부의 커넥티드 차량의 파일롯 정책에 대해 고찰하였다. SCMS의 필요성에 대한 논의에서 차량과 차량 사이에 SCMS의 역할과 책임성이 중요하다는 사실을 강조하였다. 보안 인증 관리시스템에서는 구조를 살펴보았는데 차량이나 RSU에 사용되는 인증서의 유형에 대해 분석하였다. 인증서에 따른 기능과 특성을 분석하였다. 또한 SCMS가 가지는 비정상 행위에 대한 탐지와 경고 기능에 대한 고찰과 함께 기본 안전성 메시지의 기능에 대해서 분석하였다. 마지막으로 현재 미국 정부가 추진하고 있는 커넥티드 차량의 파일롯 프로젝트의 현황을 분석하였다. 테스트에 사용되는 환경과 함께 관련 메시지에 대해서도 분석하였다. 파일롯 프로젝트를 추진함에 있어서 발생하는 논의점에 대해서도 살펴보았다.

• 자동차안전학회지
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• 제13권1호
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• pp.31-37
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• 2021

SCMS is a security credential management system for V2X communication, which performs generation/ provision/validation of device's security certificates. In this paper, we will explain about the main functions of SCMS and the role of each institution, and propose the following improvement measures in the process of establishing the Korean V2X security certification system. First, connection scheme of ERA (Enrollment certificate RA) between SCMS and Vehicle Manager Information System (VIMS) will be proposed. Second part is the problem of certificate revocation and proposal of improvements.

• 한국멀티미디어학회논문지
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• 제17권1호
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• pp.52-59
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• 2014

오늘날 스마트카드 시장이 급속히 성장하고, 응용분야가 확대됨에 따른 문제점들을 해결하기 위해 보안성, 발급 업무 편의성 및 유지 관리 업무 효율성을 높이기 위한 스마트카드 관리 시스템이 활용된다. 스마트카드 관리 시스템은 카드 관리, 발급 관리, 키 관리, 응용 관리, 발급처 관리 등으로 구성 되어 있다. 스마트카드 관리 시스템은 스마트카드를 발급하고자 하는 카드 발급사(은행, 카드사, 이동통신사 등)가 스마트카드를 구매 및 발급하여 일반 사용자들에게 배포한다. 그리고 카드 사용자의 향후 지속적인 사용을 위해 칩에 새로운 프로그램을 다운로드 해 주고 또한 이에 관련한 데이터를 안전하고 효율적으로 관리하는 기능을 제공한다. 본 연구에서는 이와 같은 스마트카드 관리 시스템을 보다 효과적인 결함분석을 수행하여 보안성을 평가하는 프레임워크와 보안성을 효율적으로 개선하는 방법을 제안한다.

• 한국자기공명학회논문지
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• 제14권2호
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• pp.55-75
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• 2010

An ion-exchanged reaction of $MnCl_2$ with Al-incorporated solid core/mesoporous shell silica (AlSCMS) followed by calcinations generated manganese species, where average oxidation state of manganese ion is 3+, in the mesoporous materials. Dehydration results in the formation of $Mn^{2+}$ ion species, which can be characterized by electron spin resonance (ESR). The chemical environments of the manganese centers in Mn-AlSCMS were investigated by diffuse reflectance, UV-VIS and ESR spectroscopic methods. Upon drying at 323 K, part of manganese is oxidized to higher oxidation state ($Mn^{3+}$ and $Mn^{4+}$) and further increase in (average) oxidation state takes place upon calcinations at 823 K. It was found that the manganese species on the wall of the Mn-AlSCMS were transformed to tetrahedral $Mn^{3+}$ or $Mn^{4+}$ and further changed to square pyramid by additional coordination to water molecules upon hydration. The oxidized $Mn^{3+}$ or $Mn^{4+}$ species on the surfaces were reversibly reduced to $Mn^{2+}$ or $Mn^{3+}$ species or lower valances by thermal process. Mn(II) species I with a well resolved sextet was observed in calcined, hydrated Mn-AlSCMS, while Mn (II) species II with g = 5.1 and 3.2 observed in dehydrated Mn-AlSCMS. Both species I and II are considered to be non-framework Mn(II).

• Advances in concrete construction
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• 제16권6호
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• pp.303-316
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• 2023

Using industrial wastes and construction and demolition (C&D) wastes is potentially advantageous for concrete production in terms of sustainability improvement. In this paper, a sustainable Self-Compacting Concrete (SCC) made with industrial wastes and C&D wastes was proposed by considerably replacing natural counterparts with recycled coarse aggregates (RCAs) and supplementary cementitious materials (SCMs) (i.e., Fly ash (FA), ground granulated blast furnace slag (GGBS) and silica fume (SF)). A total of 12 SCC mixes with various RCAs and different combination SCMs were prepared, which comprise binary, ternary and quaternary mixes. The mechanical properties in terms of compressive strength and static elasticity modulus of recycled aggregates (RA-SCC) mixes were determined and analyzed. Microstructural study was implemented to analyze the reason of improvement on mechanical properties. By means of life cycle assessment (LCA) method, the environmental impacts of RA-SCC with various RCAs and SCMs were quantified, analyzed and compared in the system boundary of "cradle-to-gate". In addition, the comparison of LCA results with respect to mechanical properties was conducted. The results demonstrate that the addition of proposed combination SCMs leads to significant improvement in mechanical properties of quaternary RA-SCC mixes with FA, GGBS and SF. Furthermore, quaternary RA-SCC mixes emit lowest environmental burdens without compromising mechanical properties. Thus, using the combination of FA, GGBS and SF as cement substitution to manufacture RA-SCC significantly improves the sustainability of SCC by minimizing the depletion of cement and non-renewable natural resources.

• Advances in concrete construction
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• 제5권3호
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• pp.289-301
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• 2017

The synergistic interactions of supplementary cementitious materials (SCMs) with ordinary portland cement (OPC) in multi-blended systems could enhance the mechanical and durability properties of concrete and increase the amount of cement that can be replaced. In this study, the characteristics of the hydration products as well as paste microstructure of blended cement containing 20% coal fly ash, 10% rice hull ash and 10% sugar mill lime sludge in quaternary blended system was investigated. Portlandite content, hydration products, compressive strength, pore size distribution and microstructural architecture of hydrated blended cement pastes were examined. The quaternary blended cement paste showed lower compressive strength, reduced amount of Portlandite phases, and higher porosity compared to plain hardened cement paste. The interaction of SCMs with OPC influenced the hydration products, resulting to the formation of ettringite and monocarboaluminate phases. The blended cement paste also showed extensive calcium silicate hydrates and calcium aluminate silicate hydrates but unrefined compared to plain cement paste. In overall, the expected synergistic reaction was significantly hindered due to the low quality of supplementary cementitious materials used. Hence, pre-treatments of SCMs must be considered to enhance their reactivity as good quality SCMs can become limited in the future.

• Macromolecular Research
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• 제13권5호
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• pp.397-402
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• 2005

To explore the potential of shell crosslinked micelle (SCM) as a drug carrier, the drug release behavior of poly($\varepsilon$-caprolactone)-b-poly(acrylic acid) (PCL-b-PAA) SCMs was investigated. PCL-b-PAA was synthesized by ring opening polymerization of $\varepsilon$-caprolactone and atom transfer radical polymerization of tert-butyl acrylate, followed by selective hydrolysis of tert-butyl ester groups to acrylic acid groups. The resulting amphiphilic polymer was used to prepare SCMs by crosslinking of PAA corona via amidation chemistry. The drug release behavior of the SCMs was studied, using pyrene as a model drug, and was compared with that of non-crosslinked micelles, especially below the critical micelle concentration (CMC). When the shell layers were crosslinked, the drug release behavior of the SCMs was successfully modulated at a controlled rate compared with that of the non-crosslinked micelles, which showed a burst release of drug within a short time.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.46-47
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• 2018

High performance concrete with low water-to-cement ratio has been widely used with increased demand of high rising buildings and huge scaled structures. Additionally, for high performance concrete, various SCMs are replaced to improve its performance from fresh state to hardened state. With the drawback of increased viscosity of the concrete mixture for high performance concrete, low-viscosity typed high range water reducer is the relatively new admixture. Therefore, as a goal of the research, under using various SCMs with wide range of content, the performance of low-viscosity typed high range water reducer was evaluated. Especially, in this research, the influence of low-viscosity typed high range water reducer on rheological properties including plastic viscosity and yield stress were assessed. As a result of the research, it is expected to provide a fundamental information of low -viscosity typed high ranged water reducer on high performance concrete with various conditions of SCMs.

• 한국항해항만학회지
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• 제30권10호
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• pp.833-837
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• 2006

해난사고를 억제하고 선박을 안전하게 운항하기 위해서는 선박을 조종하는 항해사와 항해사의 항해 수행을 보조하는 시스템의 효과적인 상호작용이 필수적이다. 본 연구에서는 항해사의 항해 수행을 지원하고 안전한 선박 운행을 확보하기 위해 개발된 SCMS(Ship Control and Management System)의 기능을 항해사의 수행과 관련지어 (1) 경계(watchkeeping), (2) 위치확인(positioning) 및 조종(maneuvering)의 측면에서 개관하고, 선박 조종 및 안전성 확보를 위해 항해사가 이 시스템과 어떠한 방식으로 상호작용하는지 기술하였다. 또한 실제 선박에 탑재된 것과 동일한 SCMS 시뮬레이터를 이용하여 항해사를 훈련할 경우 선박조종을 위한 교육시간이 훨씬 단축될 수 있다는 것과, 실제 항해 실습 과정에서 경험하는 선박조종에서의 안전 정도(특히 조종 부문에서)도 급격히 상승함을 경험적 자료를 통해 확인하였다.

• 턱관절균형의학회지
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• 제6권1호
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• pp.1-4
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• 2016

FCST의 턱관절 불균형 진단은 검사자 및 환자의 주관에 의존하여 이루어지기 때문에 객관적인 진단 방법에 대한 고찰이 필요하다. 본 증례에서는 FCST 진단 방법 중 경추회전제한 검사에 대한 객관적인 검증 방법으로 표면 근전도 측정이 가능성이 있음을 관찰하였다.