• Asia pacific journal of information systems
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• 제29권2호
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• pp.268-282
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• 2019

This study attempts to synthesize the literature on radicalization and examine the role of social media in promoting radicalization. The study is based on the review of prominent studies on radicalization in both offline and online settings. The study builds upon the literature in offline settings on radicalisation and presents a research agenda for radicalization in online settings. The study also presents a model of radicalization delineating the role of social media.

• 한국재료학회지
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• 제23권5호
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• pp.260-265
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• 2013

Silicon nanoparticle is a promising material for electronic devices, photovoltaics, and biological applications. Here, we synthesize silicon nanoparticles via $CO_2$ laser pyrolysis and study the hydrogen flow effects on the characteristics of silicon nanoparticles using high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and UV-Vis-NIR spectrophotometry. In $CO_2$ laser pyrolysis, used to synthesize the silicon nanoparticles, the wavelength of the $CO_2$ laser matches the absorption cross section of silane. Silane absorbs the $CO_2$ laser energy at a wavelength of $10.6{\mu}m$. Therefore, the laser excites silane, dissociating it to Si radical. Finally, nucleation and growth of the Si radicals generates various silicon nanoparticle. In addition, researchers can introduce hydrogen gas into silane to control the characteristics of silicon nanoparticles. Changing the hydrogen flow rate affects the nanoparticle size and crystallinity of silicon nanoparticles. Specifically, a high hydrogen flow rate produces small silicon nanoparticles and induces low crystallinity. We attribute these characteristics to the low density of the Si precursor, high hydrogen passivation probability on the surface of the silicon nanoparticles, and low reaction temperature during the synthesis.

• 한국정보관리학회:학술대회논문집
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• 한국정보관리학회 1995년도 제2회 학술대회 논문집
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• pp.25-28
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• 1995

Whereas earlier research on information seeking efforts focused on system related concepts and observer constructs. the recent literature reflects a move toward user consturcts. The purpose of the study is to review, analyze and synthesize the various models on information seeking. The study suggests that the practice of intermediares can be both more efficient and effective if it is based on the conceptual assumptions that undergird the cognitive factors: systems designs or software access will also benefit if these cognitive factors are built into the information system as centeral design features.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.240-244
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• 2001

Recycling process involving mechanical, thermal, hydrometallurgical, and sol-gel step has been applied to recover cobalt and lithium from spent lithium ion batteries and to synthesize LiCoO$_2$from leach liquor as cathodic active materials. Electrode materials containing lithium and cobalt could be concentrated with 2-step thermal and mechanical treatment. Leaching behaviors of the lithium and cobalt in nitric acid media was investigated in terms of reaction variables. Hydrogen peroxide in 1 M HNO$_3$solution turned out to be an effective reducing agent by enhancing the leaching efficiency. O f many possible processes to produce LiCoO$_2$, the amorphous citrate precursor process (ACP) has been applied to synthesize powders with a large specific surface area and an exact stoichiometry. After leaching used LiCoO$_2$with nitric acid, the molar ratio of Li/Co in the leach liquor was adjusted at 1.1 by adding a fresh LiNO$_3$solution. Then, 1 M citric acid solution at a 100% stoichiometry was also added to prepare a gelatinous precursor. When the precursor was calcined at 95$0^{\circ}C$ for 24 hr, purely crystalline LiCoO$_2$was successfully obtained. The particle size and specific surface area of the resulting crystalline powders were 20 пm and 30 $\textrm{cm}^2$/g, respectively The LiCoO$_2$powder was proved to have good characteristics as cathode active materials in charge/discharge capacity and cyclic performance.

• 한국통신학회논문지
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• 제32권6C호
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• pp.572-578
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• 2007

영상 회의 시스템에서는 현실감을 높이기 위하여 대화 상대방과 시선을 맞추는 eye contact을 만들어 주는 것이 중요하다. 이를 위하여 영상 기반 방법과 모델 기반 방법 등의 시점합성기법이 연구되고 있다. 전자는 계산이 간단하나 부정확하고, 후자는 잡음에 강하고 정확한 영상을 만들어 내지만 시간이 많이 걸리는 단점이 있다. 본 논문에서는 얼굴 영상을 타원으로 근사화시키고 이를 3차원 공간에서 타원체로 모델링하여 임의의 가상 카메라의 위치에서 영상을 합성하는 방법을 제안하였다. 여러 가지 실험을 통하여 제안한 방법이 계산량이 적으면서도 성능이 우수함을 입증하였다.

• 대한기계학회논문집A
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• 제20권11호
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• pp.3507-3515
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• 1996

This paper presents an attempt to find the physical structure of dynamic systems which achieves the behavior of a given system function. The scheme pursued by the paper would be regarded as synthesizing dynamic systems, and a method to synthesize them analytically is proposed by means of bond graph prototypes. The method adopts several conceptsused to synthesize networks in the electrical field, but yet deconstrates its own strengths such as the freedom from assigning causality and determining junction types. Also, itis shown that this method has further advantages in reticulating a given specification into feedforward and feedback components relative to network synthesis and the method is examined though an example to trace the outline of the analytical synthesis of dynamic systems using bond graph prototypes.

• Archives of Pharmacal Research
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• 제28권7호
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• pp.756-760
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• 2005

Polyene macrolide amphotericin B (AmB) is the drug of choice for the treatment of disseminated fungal infections. However, because of its pronounced side effects, the drug has limited applicability. There are few interesting reports, which state that co-administration of the drug with homo-peptide of polyaspartic acid reduces the side effects of the drug. In our present study, an approach has been made to systematically synthesize low molecular weight heteropeptides consisting of L-aspartic acid and its derivative. It was hypothesized that such heteropeptides will reduce the toxic side effects of the drug by facile hydrophobic binding between the polymer and the drug. We have employed the strategy of solid phase peptide synthesis (SPPS) to synthesize low molecular weight hetero-peptides by using L-aspartic acid and benzyl-L-aspartic acid to induce the hydrophobic binding between the peptide and the drug. In future, the proposed methodology can be employed to tailor other polypeptides substituted with benzyl groups to reduce the nephrotoxicity of AmB.

• Applied Microscopy
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• 제45권3호
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• pp.119-125
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• 2015

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) have attracted significant attention due to their unique and exotic properties attributed to their low dimensionality. In particular, semiconducting 2D TMDCs such as $MoS_2$, $WS_2$, $MoSe_2$, and $WSe_2$ have been demonstrated to be feasible for various advanced electronic and optical applications. In these regards, process to synthesize high quality 2D TMDCs layers with high reliability, wafer-scale uniformity, controllable layer number and excellent electronic properties is essential in order to use 2D TMDCs in practical applications. Vapor deposition techniques, such as physical vapor deposition, chemical vapor deposition and atomic layer deposition, could be promising processes to produce high quality 2D TMDCs due to high purity, thickness controllability and thickness uniformity. In this article, we briefly review recent research trend on vapor deposition techniques to synthesize 2D TMDCs.

• 대한수학교육학회지:수학교육학연구
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• 제19권4호
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• pp.531-543
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• 2009

본 연구는 중학교 2학년 기하 문제를 해결하는 데 필요한 속성이 무엇인지를 확인하고, 학생들이 그러한 속성을 얼마나 숙달하고 있는지를 분석하였다. 중학교 2학년 기하 영역의 선다형 문항은 회상하기, 분석하기, 정당화하기, 종합하기, 비정형 문제해결의 5가지 속성을 요구하고 있었으며, 이것은 수학 교사들의 내용적 판단뿐 아니라 인지진단이론의 모수에 의해서도 확인되었다. 학생들은 정당화하기와 종합하기의 속성을 많이 숙달하지 못한 편으로 나타났다. 5가지 속성은 서로 높은 상관관계가 있었으며, 회귀분석 결과 분석하기가 기하 성취도 변화를 가장 잘 예측하는 변수였다. 성취수준별로 숙달한 속성의 수는 달랐는데, 중 수준 학생들은 상 수준과 비교하여 정당화하기, 비정형 문제해결의 숙달 비율이 낮았으며, 하 수준 학생들은 종합하기나 정당화하기의 속성을 거의 숙달하지 못했고 회상하기, 분석하기, 비정형 문제해결의 속성 또한 30% 미만의 학생들이 숙달하고 있었다. 이 결과는 개인에 따라 다른 정보를 제공하고 학생 개개인의 강점과 약점을 산출해준다는 점에서 학생 평가에 유용하게 활용될 수 있다.

• 한국수학교육학회지시리즈A:수학교육
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• 제59권4호
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• pp.331-355
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• 2020

본 연구의 목적은 수학적 신념에 관한 기존 연구 결과를 체계적으로 분석하여 가치 있는 결과들을 비교 및 종합하고 이로부터 수학적 신념에 관한 후속 연구의 시사점을 얻는 것이다. 선정된 논문 58편의 방법론적 질을 MQA(Methodological Quality Assessment) 체크리스트를 이용하여 확인한 결과, 설문지를 이용하여 수학적 신념을 조사했거나 예비교사를 대상으로 한 연구가 많았다. 연구 결과를 분석한 결과, 수학적 신념의 개념적 특징과 대상별 특징, 수학적 신념의 교육적 영향력으로 나누어 그 의미를 확인했다. 수학적 신념은 교사와 학생, 수학 수업의 실천에서 중요한 교육적 영향력을 가지고 있었다. 연구 결과는 교사가 학생의 사고에 주목하여 적절한 교육적 지원을 제공하지 못하는 문제를 해결하기 위해 학생과 교사의 신념을 변화시키는 것이 중요함을 강조하며, 학생의 수학적 사고에 초점을 둔 수업 실천을 위한 지원이 필요함을 보여준다.