응용 및 융합 기술 : 디지털 무선 마을방송 시스템을 위한 서비스 커버리지 분석

최다솜 ( Da-some Choi ),강영흥 ( Young-heung Kang ) 한국항행학회 2015 韓國航行學會論文誌 Vol.19 No.6

기존 아날로그 마을방송 시스템은 우천 시 나 기후변화에 따른 선로영향이 크고 원거리 정보전달력이 미흡한 문제 등으로 인하여 디지털 시스템으로의 전환과 이에 따른 시스템 표준이 요구되고 있다. 효율적인 디지털 무선 마을 방송 시스템을 구축하기 위해서는 서비스 커버리지 등 전파환경의 다양성을 분석할 필요가 있다. 본 논문은 송신 출력을 파라미터로 설정한 후 지역 환경을 고려한 대도시 지역, 산간 지역, 평야지역으로 나누어 SMIS (spectrum management intelligence system)을 이용하여 각 지역의 서비스 커버리지의 면적 비율과 인근지역에 영향을 미치는 간섭 면적 비율을 분석 평가하였다. 본 논문의 결과는 다양한 환경에서의 전파 수신전력 및 환경별 전파 특징을 예측하고 마을 방송 표준을 확립하는 기초적인 자료로 활용될 것이다. Since, the existing analog village broadcasting system had been affected by the climate change such as rain and had some problems likes as short range, it had been changed to the digital system and its standardizations required to be developed from now. In order to deploy the efficient digital wireless village broadcasting system, some propagation profiles as well as service coverages should be analyzed in various radio environments. In this paper, we have set up the transmission power as a parameter and estimated the service coverage area ratio as well as the area ratio interfered into the nearby village in rural, suburban and urban environments using spectrum management intelligence system (SMIS). This paper provides the basic data to establish a standard using the radio propagation characteristics and received power for village broadcasting system in various environments.

Pluralización de haber impersonal en el aprendizaje de español en Corea

( Somee Hur ) 한국스페인어문학회(구 한국서어서문학회) 2020 스페인어문학 Vol.0 No.95

This paper presents the selection of singular/plural forms of the impersonal verb haber, one of the most interesting phenomena of spoken and written Spanish nowadays. These forms, according to the standard/non-standard uses respectively based on the Spanish academic norm, have always been subject to debate among grammarians and linguists on both sides of the Atlantic. Therefore, the article considers beforehand several existing studies and examples of the verb haber throughout the evolution of Spanish. For the purpose of dealing with the subject in the field of education, we included traditional grammars in Spanish and the contents of grammar books dedicated to international and Korean students. In traditional studies, the meaning of ‘existence’ of the verb is highlighted and its plural use is sometimes added. Most resources for learning Spanish explain the impersonal form in present hay at the basic level without mentioning its singular form in other verb tenses. To know the influence of these explanations on Korean students who learn and speak Spanish, we have obtained related corpus with interviews consisting of 26 questions. Results from sociolinguistic analysis indicate that all survey participants knew the impersonal verb haber always remains singular in present tense, whether the noun phrase that follows is singular or plural. Nevertheless, it does not occur the same in the past and future verb tenses since 35% of the respondents pluralize this verb in simple tenses and 44% in compound tenses. Finally, we add a reflection on whether the pluralization of haber can be linked to Spanish-speaking countries where students learn the language or is it a mere confusion that they make in relation to its auxiliary function.

Fast synthesis of high-quality reduced graphene oxide at room temperature under light exposure.

Some, Surajit,Kim, Sungjin,Samanta, Khokan,Kim, Youngmin,Yoon, Yeoheung,Park, Younghun,Lee, Sae Mi,Lee, Keunsik,Lee, Hyoyoung RSC Pub 2014 Nanoscale Vol.6 No.19

<P>An approach of presenting new reducing reagents, sodium-benzophenone (Na-B) or Na-B in the presence of the hydrazine (Na-B-H) system under light exposure could produce rGOs with/without N-doping at room temperature in both the solution phase and on a solid substrate. Benzophenone activated those solutions acting as a photosensitizer under light. It was assumed that the newly generated radical anions with electrons from Na-B under light can reduce GO to rGO sheets (rGONa-B1). In addition, the Na-B-H system can allow a higher degree of reduction with the doping of nitrogen atoms by the introduction of hydrazine to produce radical anions and electrons with a sodium hydrazide complex, which helps decrease the sheet resistance of the as-made rGONa-B-H2. The excellent properties (very low oxygen content (C/O 16.2), and low sheet resistance (130 ω square(-1))) of the rGOs were confirmed by XPS, XRD, IR, Raman spectroscopy, TGA, wettability, and sheet resistance measurements. High-quality rGO films on flexible substrates could be prepared by directly immersing the GO films in these solutions for several minutes.</P>

Binol salt as a completely removable graphene surfactant

Some, Surajit,Kim, Youngmin,Hwang, EunHee,Yoo, HeeJoun,Lee, Hyoyoung The Royal Society of Chemistry 2012 Chemical communications Vol.48 No.62

<P>For the first time, stable aqueous dispersions of graphene sheets can be prepared <I>via</I> exfoliation/<I>in situ</I> reduction of graphene oxide in the presence of binol salt, a stabilizing surfactant that can be completely removed without affecting the properties of graphene sheets.</P> <P>Graphic Abstract</P><P>For the first time, stable aqueous dispersions of graphene sheets can be prepared <I>via</I> exfoliation/<I>in situ</I> reduction of graphene oxide in the presence of a stabilizing surfactant, binol salt, which can be completely removed without affecting the properties of graphene sheets. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cc33916a'> </P>

Dual Functions of Highly Potent Graphene Derivative–Poly-<small>l</small>-Lysine Composites To Inhibit Bacteria and Support Human Cells

Some, Surajit,Ho, Seok-Man,Dua, Pooja,Hwang, Eunhee,Shin, Young Hun,Yoo, HeeJoun,Kang, Jong-Sun,Lee, Dong-ki,Lee, Hyoyoung American Chemical Society 2012 ACS NANO Vol.6 No.8

<P>Dual-function poly(<SMALL>l</SMALL>-lysine) (PLL) composites that function as antibacterial agents and promote the growth of human cell culture have been sought by researchers for a long period. In this paper, we report the preparation of new graphene derivative–PLL composites <I>via</I> electrostatic interactions and covalent bonding between graphene derivatives and PLL. The resulting composites were characterized by infrared spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. The novel dual function of PLL composites, specifically antibacterial activity and biocompatibility with human cells [human adipose-derived stem cells and non-small-cell lung carcinoma cells (A549)], was carefully investigated. Graphene–DS–PLL composites composed of 4-carboxylic acid benzene diazonium salt (DS) generated more anionic carboxylic acid groups to bind to cationic PLLs, forming the most potent antibacterial agent among PLL and PLL composites with high biocompatibility with human cell culture. This dual functionality can be used to inhibit bacterial growth while enhancing human cell growth.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2012/ancac3.2012.6.issue-8/nn302215y/production/images/medium/nn-2012-02215y_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn302215y'>ACS Electronic Supporting Info</A></P>

E-Government as a Tool for Eradicating Corruption in Public Sector: The African Perspective

( Osman Abdul Somed ),( Happiness Kavishe Tairo ),( Mohamed Mintanga Milulu ),( Sani Yashe Hussaini ),( Shadrack Mensah ) 한국정책학회 2015 한국정책학회 추계학술발표논문집 Vol.2015 No.-

Corruption has been identified as a bane to economic development across the globe and the single most serious obstacle to achieving the Millennium Development Goals in Africa in particular. The persistence of the situation despite the enactment of anti-corruption policies to check the practice is a course for concern. The aim in this study is to explore how e-Government could serve as a tool to facilitate the implementation of anti-corruption policies in the three countries which includes Ghana, Tanzania, and Nigeria in perspective. Based on the case analysis, the study found that corruption operates in an atmosphere of uncertainty, excessive use of discretion and relaxed laws. Results suggest that the deployment of e-Government will clarify roles, reduce the use of discretion and human contact and also leave identifiable trails by way of data on actions taken. Finally, the article points out the study``s managerial and policy implications and directions for future research.

Evaluation of e-Government Initiatives: Focus On Ghana Revenue Authority and Registrar Generals Department

( Osman Abdul Somed ) 한국정책학회 2015 한국정책학회 동계학술발표논문집 Vol.2015 No.-

The level of confidence in e-Government as a means to efficient public service delivery is on the rise and many governments have deployed the system at a very high cost. Evaluation research as a growing body of knowledge is crucial to successful project implementation, especially in developing countries where the tendency to transfer technologies in this sector without much inference is high. Evaluation will provide reliable information on the feasibility and relevance of adopted technologies, and will serve as frame of reference in similar initiatives. Achievement of e-Government goals is positively affected by Information quality, system quality, service quality and a user characteristic is the question being investigated. An evaluation framework has been proposed from interpolation of the context variables. The expected findings are that system goals positively correlates with the independent variables if moderating factors are held constant. The study will contribute to modification of e-government policy, theory and practice especially for emerging e-government systems. The limitation has been stated in the conclusion.

Highly hydrophilic and insulating fluorinated reduced graphene oxide

Samanta, Khokan,Some, Surajit,Kim, Youngmin,Yoon, Yeoheung,Min, Misook,Lee, Sae Mi,Park, Younghun,Lee, Hyoyoung The Royal Society of Chemistry 2013 Chemical communications Vol.49 No.79

<P>A facile method for the synthesis of highly fluorinated reduced graphene oxide from graphene oxide using BF<SUB>3</SUB>-OEt<SUB>2</SUB> solution and alkylthiol/alkylamine on the Gram scale has been described using a detailed mechanism. The maximum fluorination was as high as 38 wt% and the fluorinated reduced graphene oxide produced has great wettability and high insulating properties.</P> <P>Graphic Abstract</P><P>A facile method for the synthesis of highly hydrophilic and insulating fluorinated reduced graphene oxide using BF<SUB>3</SUB>-OEt<SUB>2</SUB> solution and alkylthiol/alkylamine. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3cc45376f'> </P>

Graphene oxide as a recyclable phase transfer catalyst

Kim, Youngmin,Some, Surajit,Lee, Hyoyoung The Royal Society of Chemistry 2013 Chemical communications Vol.49 No.50

<P>We demonstrated a simple and green chemical method to obtain Michael adducts and their derivatives by using GO as a phase transfer catalyst with different kinds of bases in water and dichloromethane, and we also used GO multiple cycles almost without reduction in reaction yields.</P> <P>Graphic Abstract</P><P>We demonstrated a simple and green chemical method to obtain Michael adducts by using graphene oxide as a recyclable phase transfer catalyst. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3cc42787k'> </P>

Self-Association-Free and Recyclable, Dimeric Cinchona Alkaloid Organocatalysts for Methanolytic Desymmetrization of meso-Glutaric Anhydrides

남은혜,박상은,오중석,some surajit,김대영,배한용,송충의 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.8