• Title/Summary/Keyword: expanded method

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Electrochemical Synthesis of Red Fluorescent Silicon Nanoparticles

  • Choi, Jonghoon;Kim, Kyobum;Han, Hyung-Seop;Hwang, Mintai P.;Lee, Kwan Hyi
    • Bulletin of the Korean Chemical Society
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    • v.35 no.1
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    • pp.35-38
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    • 2014
  • Herein, we report on the preparation of red fluorescent Si nanoparticles stabilized with styrene. Nano-sized Si particles emit fluorescence under UV excitation, which could be used to open up new applications in the fields of optics and semi-conductor research. Unfortunately, conventional methods for the preparation of red fluorescent Si nanoparticles suffer from the lack of a fully-established standard synthesis protocol. A common initial approach during the preparation of semi-conductors is the etching of crystalline Si wafers in a HF/ethanol/$H_2O$ bath, which provides a uniformly-etched surface of nanopores amenable for further nano-sized modifications via tuning of various parameters. Subsequent sonication of the etched surface crumbles the pores on the wafer, resulting in the dispersion of particles into the solution. In this study, we use styrene to occupy these platforms to stabilize the surface. We determine that the liberated silicon particles in ethanol solution interact with styrene, resulting in the substitution of Si-H bonds with those of Si-C as determined via UV photo-catalysis. The synthesized styrene-coated Si nanoparticles exhibit a stable, bright, red fluorescence under excitation with a 365 nm UV light, and yield approximately 100 mg per wafer with a synthesis time of 2 h. We believe this protocol could be further expanded as a cost-effective and high-throughput standard method in the preparation of red fluorescent Si nanoparticles.

Developing a Conceptual Model for Measuring the Electronic Commerce Success of Online Game Websites (온라인게임 웹사이트의 전자상거래 성공측정모델의 개발에 관한 연구)

  • Hong, Ilyoo
    • Informatization Policy
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    • v.19 no.1
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    • pp.45-73
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    • 2012
  • Most online games today are provided via a website interface. Researchers found that various aspects of a game website importantly influence the success of the online game business. This paper aims at identifying key site-related quality factors affecting the success of online casual game websites and creating a model for measuring such success. To meet this end, we extracted basic factors from the literature and expanded them through a Delphi survey method in which domain experts were asked to identify key quality factors of online game websites. Then we performed a questionnaire survey using online game users for an empirical analysis. The results revealed that information quality, service quality, and system quality are all positively related to user satisfaction and that an increase in user satisfaction leads to an improvement in both gamer loyalty and business outcomes. However, it was found that gamers' loyalty does not necessarily increase business outcomes. The paper offers practical as well as academic implications based on the research findings.

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Design of Thomson Scattering System Using VPH Grating for Plasma Processing

  • Joa, Sang-Beom;Ko, Min-Guk;Kang, In-Je;Yang, Jong-Keun;Yu, Yong-Hun;Lee, Heon-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.525-525
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    • 2013
  • Low temperature plasma diagnosis is one of the big issues in laboratory scale or processing industry. One of the most powerful techniques of plasma diagnostics is the use of the scattering of electromagnetic radiation from the plasma. Electron temperature and density are important parameters for understanding the information of plasmas in the plasma processing industry. Laser scattering experiments on plasma can provide a substantial amount of information about plasma parameters such as the electron density ne, the electron temperature Te, and the neutral density nn and temperature Tn. Thomson scattering spectroscopy is used several method, in accordance with detector type. Commonly, Thomson scattering is used several notch filter to separate expanded wavelength. Since using a spectrometer with surface relief grating or notch filter, the system of the measurement will be complicated and bigger. In this study, using VPHG (Volume Phase Holographic Grating) in order to install the simple and cheap system. VPHG has the advantage of the system installation, because it can be Transmission Type. The diffraction efficiency and dispersion angle of VPHG is higher than the surface relief grating relatively. For a wavelength and bandwidth selection, Using a slit or mask to select a rejection wavelength instead of notch filter.

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Consideration in the Interpretation of the Pyeongwi-san Prescription (평위산의 방론에 대한 고찰)

  • Choe, Ung-Sik;Lee, Won-Yung;Jeong, Gi-Hoon;Seo, Young-Bae
    • Herbal Formula Science
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    • v.23 no.2
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    • pp.225-233
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    • 2015
  • Objectives : The purpose of this study was to investigate the interpretation of the Pyeongwi-san(PWS) prescription in order to obtain the evidence for clinical applications. Methods and Result : We interpreted on the PWS-related contents based on 15 classic books, analyzed it according to followed categories ; origin, indication and precaution, usage, meaning of name, physiological and pathological situation of PWS, explain about each herbs. Conclusion : 1. PWS was first mentioned in the Bakjebang, its application was enhancing appetite. Application of PWS not only expanded digestive disease, infectious disease, and pain in articular, but also used to toniyfing drug. 2. Generous application method of PWS was ‘Sujunbok(水煎服)’. Pill preparation(丸劑) and decoction with salt(鹽湯劑) were also used 3. "Pyeongwi(平胃)“ in PWS means "flatten the stomach". There are some theory about methodology to "Pyeongwi (平胃)“, one is "drain the pathogen in stomach(敦阜說)”, other is "tonifying stomach's healthy qi(卑監說)“, the other is compromise theory. 4. Most medical literature related application situation of PWS to dampness(濕邪) in stomach. In Gangsulwongobangsunju, there are more detailed explain focused on metal qi(金氣), and fire qi(火氣) 5. Atractylodes japonica Koidz(蒼朮) drys dampness and fortifys the spleen, Magnolia officinalis Rehder(厚朴) eliminates dampness and treats fullness, Citrus reticulata Blanco(陳皮) moves and drains qi, Glycyrrhiza uralensis Fisch(甘草) tonify and harmonize in herbal formula

A Study of Security Requirement in Wireless Charging (무선충전에서 보안요구사항에 관한 연구)

  • Lee, Keun-Ho
    • Journal of the Korea Convergence Society
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    • v.5 no.3
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    • pp.23-27
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    • 2014
  • In recent times, there is an increasing interest in wireless charge of smartphones and devices, and many companies are developing wireless charges. The range of application of wireless charge would be expanded to almost all electronics, including not only mobile devices, but also notebook computers and vacuum cleaners. On-line electric vehicles are to be launched in the market this year in a massive scale. As such wireless charge-related markets are inexhaustible. Wireless charge is included in the world's top 10 promising technologies, and its rapid growth is expected to have annual growth by more than 100%. However, there's a need to establish a safe environment, by analyzing security threats to technical limitations and harmfulness to human body, and arrange institutional compliments. The development of communication method for a variety of wireless charging are delivering comfortable and safe information. This paper aims to examine the factors to threaten electric vehicle, which are usually intruded through network system and analyzes security threats to and security requirements for magnetic resonance mode-based wireless charge in mobile devices, and suggests security requirements.

Inverse Scattering Technique with Series Expanded Field of Dielectric Cylinders in Angular Spectral Domain (각스펙트럼 영역에서 전개함수 전계를 이용한 유전체 실린더에서의 역산란)

  • Kim, Ha-Chul;Choi, Hyun-Chul;Son, Hyon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.9 no.5
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    • pp.698-707
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    • 1998
  • For inverse scattering problems reconstructing cross-sectional permittivity distributions of dielectric cylinders, the angular spectral inverse technique using the moment method with pulse basis function suffers from large reconstruction error even if very small noise due to requiring the higher spectral informations on the larger cross-section of the cylinder. To reduce the number of higher-order spectra, this paper presents an improved inverse technique in angular spectral domain applying the moment procedure with a series-expansion basis function for the induced field in each enlarged cross-sectional cell. By choosing adequate spectra and averaging over the enlarged cells with a suitable weighting function, the reconstruction profiles reveal fine enough to suppress the noise effect significantly.

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Three-dimensional evaluation of tooth movement in Class II malocclusions treated without extraction by orthodontic mini-implant anchorage

  • Ali, Dler;Mohammed, Hnd;Koo, Seung-Hwan;Kang, Kyung-Hwa;Kim, Sang-Cheol
    • The korean journal of orthodontics
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    • v.46 no.5
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    • pp.280-289
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    • 2016
  • Objective: The aim of this study was to analyze tooth movement and arch width changes in maxillary dentition following nonextraction treatment with orthodontic mini-implant (OMI) anchorage in Class II division 1 malocclusions. Methods: Seventeen adult patients diagnosed with Angle's Class II division 1 malocclusion were treated by nonextraction with OMIs as anchorage for distalization of whole maxillary dentition. Three-dimensional virtual maxillary models were superimposed with the best-fit method at the pretreatment and post-treatment stages. Linear, angular, and arch width variables were measured using Rapidform 2006 software, and analyzed by the paired t -test. Results: All maxillary teeth showed statistically significant movement posteriorly (p < 0.05). There were no significant changes in the vertical position of the maxillary teeth, except that the second molars were extruded (0.86 mm, p < 0.01). The maxillary first and second molars were rotated distal-in ($4.5^{\circ}$, p < 0.001; $3.0^{\circ}$, p < 0.05, respectively). The intersecond molar width increased slightly (0.1 mm, p > 0.05) and the intercanine, interfirst premolar, intersecond premolar, and interfirst molar widths increased significantly (2.2 mm, p < 0.01; 2.2 mm, p < 0.05; 1.9 mm, p < 0.01; 2.0 mm, p < 0.01; respectively). Conclusions: Nonextraction treatment with OMI anchorage for Class II division 1 malocclusions could retract the whole maxillary dentition to achieve a Class I canine and molar relationship without a change in the vertical position of the teeth; however, the second molars were significantly extruded. Simultaneously, the maxillary arch was shown to be expanded with distal-in rotation of the molars.

An Explorative Study on the Culture of Poverty (빈곤문화실태에 대한 탐색적 연구 - 긴급구호시설 종사자들을 대상으로 -)

  • Lee, Jin-Sook
    • Korean Journal of Social Welfare
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    • v.56 no.4
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    • pp.149-172
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    • 2004
  • The main purpose of this study is to explore and understand the reality of culture of poverty that employees of emergent relief facilities recognize. For this purpose, it had been carried out questionnaire with employees of emergent relief facilities from November to December 2003. It was applied quantitative research method to this study. Major findings of the study are as follows: 1) the awareness of employees to facilities in which they work is positive, 2) but their awareness to service user is negative(the degree of individual characteristic, educational characteristic and economical characteristic of service user is generally negative, while the degree of familial characteristic is generally positive), 3) the awareness to relationship with service user is positive. The results of this study reveal possibility that the culture of poverty can be expanded under the poor and psychic rehabilitation programs should be reinforced.

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A Study on the Planning Directions of Railway Station from the Perspective of Place Branding (플레이스 브랜딩 관점에서 본 철도역사의 계획방향 연구)

  • Woo, Hee-Kyung;Chu, Beom
    • Korean Institute of Interior Design Journal
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    • v.23 no.1
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    • pp.172-180
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    • 2014
  • A railway station appears in the form of multi-use station building where cultural and commercial elements such as shopping and leisure are mixed, getting out of simple space configuration oriented to the space for station work, where a passenger stays for a little while. Now, a railway station is a place expanded to the inside of city, and builds a relationship with urban fabric, and therefore it should receive the social change in the time together with the surrounding infrastructure, and should inevitably form the urban environment. And it should become the 'Place' so as to be capable of playing a role of buffer and a role of regional gateway landmark by making users included in the inside through various uses with regard to the dispersed urban connection. Hence, this study is intended to examine the planning through the place branding of railway station. In the method of research, the characteristics that place branding had was investigated, and an analysis was made on the basis of 10 place branding strategic elements and 6 railway design guidelines. And it was intended to set a direction in which the existing place branding strategy could be applied to the railway station, and was intended to derive the place branding planning strategic elements of railway station. Hence, the planning can be classified into the following 5 kinds in connection with railway station. First, identity should be embodied through the strategy of constructing the symbolic image of railway station. Second, a role of mediating variously approaching flows in the city should be played. Third, the spatial layout of railway station, which can increase the efficiency of use, should be arranged. Fourth, special characteristics should be intensified through creative storytelling that stimulates emotion. Fifth, an organic change is gradually necessary for sustainability. These planning elements should be applied in harmonious combination. Therefore, a new railway station can be maded by building identity and placeness and by giving the value through these planning directions in the future.

A Method of Selecting Open Source Software by IFCS (IFCS에 의한 오픈소스 소프트웨어 선정기법)

  • Jeon, Hye-Young;Jin, Jing-Shu;Rhew, Sung-Yul
    • The KIPS Transactions:PartD
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    • v.17D no.2
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    • pp.119-128
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    • 2010
  • The application field of OSS is being expanded farther and the existing studies are well established theoretically but not actually widely used. Because so many criteria and complexity of selection methods result in low efficiency and not proper for use. In this master's thesis, to solve these problems I propose a selecting technique for OSS with less criteria, which is more effective and easy to use than before. Based on the existing studies, we identify assessment criteria which common used and redefine 14 evaluation attributes as well as 31 assessment criteria through elimination and grouping. And evaluate the criteria in four steps such as Initial assessment, Functional assessment, Characteristical assessment and Supplemental assessment. To evaluate the adequacy of suggested technique, 29 database management tools for MySQL are selected as candidates, and applied to the technique I proposed. As the result, time and effort for evaluation is reduced sharply and we can use this technique more easily.