• Title/Summary/Keyword: Diamond Model

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A Verification of Diamond Nucleation Model

  • Yugo, S.;Kimura, T.
    • The Korean Journal of Ceramics
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    • v.2 no.4
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    • pp.181-183
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    • 1996
  • We found that our initial model agrees with most of the recent reports; however, it does not agree with some of them with respect to the kinetics of nucleus formation. This disagreement stems from the question of whether or not a nucleus precursor should be treated as an embryonic cluster.

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Stochastic Analysis of the Diamond Particle Distribution on the Surface of Circular Diamond Saw Blade (원형 다이아몬드 톱의 세그먼트 표면에서의 다이아몬드 입자 분포의 확률적인 해석)

  • 이현우;변서봉;정기정;김용석
    • Journal of Powder Materials
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    • v.10 no.3
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    • pp.201-208
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    • 2003
  • Distributions of diamond particles protruding on the surface of worn diamond segments in circular saw has been investigated. Scanning electron microscope was used to examine the worn ,surface and radial saw blade wear and grinding ratio was measured. The number of protruded diamond particle was approximately 50% of the total number of particles, and that was independent of diamond particle concentration and table speed. It was also noted that the inter-particle distance did not follow a symmetric function like Gaussian distribution function, instead it fitted well with a probability density function based on gamma function. The distribution of inter-particle spacing, therefore, was analyzed using a gamma function model.

Role of Charge Produced by the Gas Activation in the CVD Diamond Process

  • Hwang, Nong-Moon;Park, Hwang-Kyoon;Suk Joong L. Kang
    • The Korean Journal of Ceramics
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    • v.3 no.1
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    • pp.5-12
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    • 1997
  • Charged carbon clusters which are formed by the gas activation are suggested to be responsible for the formation of the metastable diamond film. The number of carbon atoms in the cluster that can reverse the stability between diamond and graphite by the capillary effect increases sensitively with increasing the surface energy ratio of graphite to diamond. The gas activation process produces charges such as electrons and ions, which are energetically the strong heterogeneous nucleation sites for the supersaturated carbon vapor, leading to the formation of the charged clusters. Once the carbon clusters are charged, the surface energy of diamond can be reduced by the electrical double layer while that of graphite cannot because diamond is dielectric and graphite is conducting. The unusual phenomena observed in the chemical vapor deposition diamond process can be successfully approached by the charged cluster model. These phenomena include the diamond deposition with the simultaneous graphite etching, which is known as the thermodynamic paradox and the preferential formation of diamond on the convex edge, which is against the well-established concept of the heterogeneous nucleation.

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A Comparative Analysis on the Competitiveness of Korean and Japanese Fashion Industry by Applying Generalized Double Diamond Model

  • Son, Mi Young;Kenji, Yokoyama
    • Asia Marketing Journal
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    • v.15 no.1
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    • pp.57-81
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    • 2013
  • The purpose of this paper is to seek ways to improve the competitiveness of Korea's fashion industry by utilizing the source of competitiveness of Japan's fashion industry, which represents the world's leading countries in terms of fashion, so that Korea can better enter the global fashion market. The study shall first compare the competitiveness of the Japanese and Korean fashion industries by utilizing the generalized double diamond model; second, provide an understanding of what the Japanese fashion industry can offer to Korean fashion industry and companies - that is, understand what the Japanese fashion industry's competitive edge is; and third, study the kind of global competitiveness that Korea's fashion industry must achieve. To adopt a generalized double diamond model to compare the competitiveness of the Korean and Japanese fashion industries, we selected 31 sub-variables to act as determinants of the model. That is, we extracted 31sub-variables by doing research of literature to analyze national competitiveness of the fashion industries. To measure these 31 sub-variables, secondary data was gathered. We collected data related to each sub-variable from various sources of Korea and Japan. And to calculate the competitiveness index, we took three steps with reference to previous studies. We found that status of the fashion industry of the two countries as it stands. That is, Japan is an advanced country of which fashion industry is domestic market-oriented while Korea is a small open economy that mainly focuses on the foreign market. Out of 31 proxy variables, Korea's fashion industry shows higher measurements relating to production and export than Japan, but Japan's fashion industry reports higher measurements than Korea in the fields of R&D, design and brand power, the rate of value added, the efficiency of companies and globalization. In order for Korea's fashion industry to achieve competitiveness in the global market, it should pursue the following development direction. First, it is very difficult for Korea to follow the footsteps of the U.S. and Japanese fashion industries that are able to take advantage of economies of scale, because Korea is smaller than those countries. Therefore, in the case of small economies such as Singapore, strengthening of international activities will practically improve domestic determinants that Korea should improve its domestic diamond by enhancing the current competitiveness of its international diamond. In other words, Korea needs to further endeavor to develop and expand global resources and markets as well as improve its competitiveness in terms of R&D, design and brand power, the rate of value-added, and the efficiency of companies. As the Korean fashion industry shows relatively advanced level of information technology and the fashion education system, it has considerable potential to grow. Korea is expected to have a huge growth potential since it has relatively higher level of information technology, fashion education system and activities than those of Japan in both the domestic diamond and international diamond. In particular, a better environment is laid out before Korea to gain competitiveness in the fashion industry due to the recently growing influence of the Korean Wave that Korea is expected to grow as a leader in the Asian market as well as in the global market.

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Thermal Properties of Diamond Films Deposited by Chemical Vapor Depositon

  • Chae, Hee-Baik;Baik, Young-Joon
    • The Korean Journal of Ceramics
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    • v.3 no.1
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    • pp.29-33
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    • 1997
  • Four diamond films were deposited by the microwave plasma assisted chemical vapor deposition method varying CH4 concentration from 2.5 to 10% in the feeding gases. Thermal conductivity was measured on these free standing films by the steady state method from 80 K to 400K. They showed higher thermal conductivity as the film deposited with lower methane concentration. One exception, 7.79% methane concentration deposited film, was observed to be the highest thermal conductivity. Phonon scattering processes were considered to analyze the thermal conductivity with the full Callaway model. The grain size and the concentration of the extended and the point defects were used as the fitting parameters. Microstructure of diamond films was investigated with the scanning electron microscopy and Raman spectroscopy.

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The theoretical issue of 'Modified Cultural Diamond' model through a single case: Focused on the street artist Banksy (일례를 통한 '보안된 문화 다이아몬드(Modified Cultural Diamond)' 모델의 이론적 쟁점화 - 스트리트 아티스트 뱅크시(Banksy)를 중심으로 -)

  • Kim, Do Eun;Lee, Jin Woo
    • Korean Association of Arts Management
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    • no.49
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    • pp.177-200
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    • 2019
  • The purpose of this study is to critically explore and make an issue of the distribution system presented by Victoria Alexander's 'Modified Cultural Diamond' model. Street artist Banksy was served as a single case, and various secondary data were collected and analyzed for the purposes of this study. First, this study examined the formation of the aesthetic discourse and the increase in the value of Banksy's works by the market intermediaries constituting the distribution system. In addition, this paper placed Banksy's actions and works in Alexander's theoretical framework and critically discussed the following three aspects of the distribution system of 'Modified Cultural Diamond': the divorce between artists and artworks by the distribution system; the ignorance of the direct connection between artist and consumer; and lastly the exclusion of the possibility of distributing works by artists. Based on this discussion, this study has significance in making a theoretical model of Alexander academically controversial.

Comparison of Corporate Security Control Level with Social Trust Index (사회 신뢰수준에 따른 기업의 보안통제 수준 비교)

  • Na, Husung;Lee, Kyung-Ho
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.27 no.3
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    • pp.673-685
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    • 2017
  • STI(Social Trust Index) indicates levels of trustworthiness, honesty and reliability among people in a society. Since the STI varies in countries, security control on cyber space should be applied differently according to the STI so that companies can protect their assets efficiently and effectively. We compare STIs between Korea and United States using the Diamond Model and investigate how the STIs affect corporate security controls in those two countries. We finally present a formula using AHP (Analytic Hierarchy Process) to measure levels of corporate security controls in different countries.

A Study on the Competitiveness Enhancement of ICT Materials, Components and Equipments Industries using Diamond Model Approach in Korea (다이아몬드 모형을 적용한 우리나라 ICT 소재, 부품, 장비 산업의 경쟁력 강화 방향)

  • Park, J.H.
    • Electronics and Telecommunications Trends
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    • v.36 no.4
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    • pp.110-117
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    • 2021
  • The development of core technologies in the 4th Industrial Revolution, such as artificial intelligence, big data, and the intelligent Internet of Things, promote digital transformation and intelligence of the manufacturing industry. To realize them, there is an increasing demand for materials, components, and equipment needed for final goods. In particular, the expansion of global value chain instability due to changes in the external environment, such as the U.S.-China trade dispute, Japan's export regulations, and Covid-19 pandemic, increases the importance of strengthening the materials, components, and equipment industry in the global market. Thus, this study presents a strategic direction for securing global industrial competitiveness of materials, components, and equipment using Michael Porter's diamond model approach.

A Study on the Cutting Conditions of Self-Induced Chattering in Micro Shaping with Diamond Tool (다이아몬드 미세형삭가공의 자려진동 발생경향에 관한 연구)

  • 임한석;이언주;김술용;안중환
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.3
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    • pp.141-149
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    • 1998
  • Diamond shaping is one of the machining strategies to make the optical micro-groove molds, and it is especially useful when the component is an assembly of the linear micro-groove array. A mirrorlike surface and an arbitrary crose-sectional curve can be easily made by the diamond tool. However, the cutting speed of shaping is relatively lower than that of the other cutting methods, and there exist an unstable cutting conditions that generate the chatter. This study is focused on the modeling of the simplified self-induced chatter of the diamond shaping, and the machinabilities of three materials are compared by cutting experiments. From the chatter model and experiments, it is found that the unstable cutting conditions exist when the depth of cut is low and cutting speed is high. It is also found that the brass is relatively good material in micro shaping than copper or aluminium from the cutting experiments.

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Wear Mwarsurement of Single Crystal Diamond Tool Using Image Processing (영상처리를 이용한 초정밀가공용 다이아몬드 공구의 마멸 측정)

  • 양민양
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.135-139
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    • 1996
  • In this a paper, a new method to measure the wear of the single crystal diamond(SCD) tool using image processing is presented. To increase resoultion, high magnifying lens is used and to enlarge the measurement field of view, a image region matching method is applied. The shape of SCD tool is modeled by mathematical analysis. Cutting edge chipping and wear are calculated by the model. This method is proved to be efficient in detecting a few micron of wear and cutting edge loss by chipping along the whole cutting edge.

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