• Title/Summary/Keyword: Diffusion Process

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Spalling of Intermetallic Compound during the Reaction between Electroless Ni(P) and Lead-free Solders (무전해 Ni(P)과 무연솔더와의 반응 중 금속간화합물의 spalling 현상에 관한 연구)

  • Sohn Yoon-Chul;Yu Jin;Kang S. K.;Shih D. Y,;Lee Taek-Yeong
    • Journal of the Microelectronics and Packaging Society
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    • v.11 no.3 s.32
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    • pp.37-45
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    • 2004
  • Electroless Ni(P) has been widely used for under bump metallization (UBM) of flip chip and surface finish layer in microelectronic packaging because of its excellent solderability, corrosion resistance, uniformity, selective deposition without photo-lithography, and also good diffusion barrier. However, the brittle fracture at solder joints and the spatting of intermetallic compound (IMC) associated with electroless Ni(P) are critical issues for its successful applications. In the present study, the mechanism of IMC spatting and microstructure change of the Ni(P) film were investigated with varying P content in the Ni(P) film (4.6,9, and $13 wt.\%$P). A reaction between Sn penetrated through the channels among $Ni_3Sn_4$ IMCs and the P-rich layer ($Ni_3P$) of the Ni(P) film formed a $Ni_3SnP$ layer. Thickening of the $Ni_3SnP$ layer led to $Ni_3Sn_4$ spatting. After $Ni_3Sn_4$ spatting, the Ni(P) film directly contacted the molten solder and the $Ni_3P$ phase further transformed into a $Ni_2P$ phase. During the crystallization process, some cracks formed in the Ni(P) film to release tensile stress accumulated from volume shrinkage of the film.

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Characterization of transparent Sb-doped $SnO_2$ conducting films by XPS analysis (XPS를 이용한 Sb-doped $SnO_2$ 투명전도막의 특성 분석)

  • 임태영;김창열;심광보;오근호
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.13 no.5
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    • pp.254-259
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    • 2003
  • In the fabrication process of transparent conducting thin films of the ATO (antimony-doped tin oxide) on a soda lime glass substrate by a sol-gel dip coating method, the effects of the $SiO_2$ buffer layer formed on the substrate and $N_2$ annealing treatment were investigated by XPS (X-ray photoelectron spectroscopy) analysis. Optical transmittance and electrical resistivity of the 400 nm-thick ATO thin films which were deposited on $SiO_2$ buffer layer/soda lime glass and then annealed under nitrogen atmosphere were 84 % and $5.0\times 10^{-3}\Omega \textrm{cm}$ respectively. The XPS analysis confirmed that a $SiO_2$ buffer layer inhibited Na ion diffusion from the substrate, resulting in prohibiting the formation of a secondary phase such as $Na_2SnO_3$ and SnO and increasing Sb ion concentration and ratio of $Sb^{5+}/Sb^{3+}$ in the film. And it was also found that $N_2$ annealing treatment leads to the reduction of $Sn^{4+}$as well as $Sb^{5+}$ however the reduction of $Sn^{4+}$ is more effective and therefore consequently results in decrease in the electrical resistivity to produce an excellent electrical properties of the film.

Effects of Solvent on the Fabrication of Poly(L-lactide) Scaffold Membranes through Phase Inversion (상전이를 통한 Poly(L-lactide) 스캐폴드 막의 제조에서의 용매의 효과)

  • Cho, Yu Song;Kim, Young Kyoung;Koo, Ja-Kyung;Park, Jong Soon
    • Membrane Journal
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    • v.24 no.2
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    • pp.113-122
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    • 2014
  • Porous poly(L-lactic acid)(PLLA) scaffold membranes were prepared via. phase separation process. Chloroform, dichloromethane and 1,4-dioxane were used as solvent and, ethyl alcohol was used as non-solvent. Morphologies, mechanical properties and mass transfer characteristics of the scaffold membranes were investigated through SEM, stress-strain test and glucose diffusion test. The scaffold membranes obtained from the casting solutions with chloroform and with dichloromethane showed similar morphologies. They showed sponge-like porous structure with the pore size in the range of $3-10{\mu}m$ and, their porosities were in 50-80% range. Using 1,4-dioxane as solvent, nano-fibrous scaffold membranes with porosities over 80% were fabricated. When the polymer content in the solution with 1,4-dioxane was lowered to 4%, highly porous, macroporous and nano-fibrous scaffold membranes were obtained. The size of the macropore was tens of the microns and the porosity was around 90%. These results indicate that the solvent has significant effect on the scaffold membrane structure and, that scaffold membranes with various structures can be fabricated through phase separation method by choosing solvent and by controlling polymer concentration in the casting solution.

A Study on Definition and Types of Migration Path of Multiple Generation Technology: Case of Customers' and Suppliers' Migration Paths in Semiconductor Technology (다세대 기술 이동경로(Migration path)의 정의 및 종류에 대한 연구: 반도체 기술의 고객 및 공급자 이동경로 사례)

  • Park, Changhyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.11
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    • pp.181-188
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    • 2019
  • The migration path of a multiple-generation technology that occurs during a technological substitution by a new technology is important to understanding the phenomenon of technological substitution, and can contribute to understanding the process of technological innovation. This research defines the concept of migration path and develops a model of the types of migration paths by multiple dimensions (actor, generation, and time) in a multiple-generation technology. Based on a literature review and tracking of migration paths according to multiple dimensions, the definitions and types of migration paths were provided, and the accuracy of the model was verified based on a case study of the semiconductor industry. The migration paths of suppliers are modeled with three types (switching, leapfrogging, and new entrance paths), and the migration paths of customers are modeled with four types (switching, leapfrogging, new entrance, and diffusion paths) in a multiple-generation technology. This research will be useful for understanding the migration paths in the phenomenon of technological substitution, and can be applied to other industries in addition to the semiconductor industry, including various actors. In addition, suppliers and customers can understand technological substitution and can establish a technology strategy against their competitors.

현대 서양복식에 나타난 이국취향 (Exoticism)에 관한 연구 -1980년대 중반~1991년의 서양복식을 중심으로- (The Study of Exoticism in Western Costume)

  • 송명진;양숙희
    • Journal of the Korean Society of Costume
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    • v.18
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    • pp.291-306
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    • 1992
  • From the mid-1980s '91s, remarkable Ethnicism and Primitivism in the Europe fashion trend could be represented as an exotic taste longing for secenery and emotion of non-europe area in the West. These phenomenon could be found out in connection with Acculturation, which means when two different cultures or more were contacted they were identified or merged in process of diffusion and change of them. This point of view was the culture anthropologic one that make a comparison and analysis of sameness and difference between cultures. The purpose of this study was to illuminate exotic taste represented in costume in the cluture-anthroplogic aspect, to compare with beauty of costume that each culture of costume and the meaning of the times due to those differences. an aspect of the exotic taste and character in the western costume that was inspected by dividing into 'Primitivism', 'Oriental element' and 'the element of a national costume in the East European bloc ' were as follows; First, Primitivism had something in common with what was pursued in the trend of Modern Art, through the late 19th century to the early 20th century. In fashion fettered by technique, the creation expressed in a free was and showed simple beauty of costume. At the same time, pure emotion expression, creative power and witty strong expression give the cognition of transcendency breaking the routine and the cognition of complexity of an included conception. Those are garments showing not only the primitive thought and mysticism but a fancy, an abstraction, and a life. Colors and accessaries which described nature and matched simple costume composition to the expression of various material or patterns transmitted the image of the primitive strongly. Second, "Drental element" which had an effect on western custome historically in a long time had outstanding luxurios adornmental beauty of custome. Extending from the Arab stated India, China, Korea, Japan, each national costume with a gay national culture became one of motif. Various ornamental factors expressed on Trapez Line, Sime Line and Drape, or Raied style, which did not restrict the body. Those were not only functional Easy Look, but were also satisfying human's ornamental desire. Third, national factors in the East European bloc are theme that begins to be embossed in the late 80's. In view of a political change and cultural situation with a double character of Europe and Orient, it was estimated that national factors have great importance in fashion. Item concerned with new concern appeared at Autumn & Winter collection. It shows elegant and graceful beauty of costume by adding a fur or jewel to simple form. These national factors in the East European bloc are simple form, but shows the difference in more cubic formation than form expressed in Primitivism or Oriental factors Exotic taste appeared form 80's to 91's, is thought to create an forgotten romantic emotion and traditional fashion

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Electrokinetic Studies on Nylon and Wool/Acid Dye System (나일론과 양모/산성염료계에 대한 계면동전위적 연구)

  • 박병기;김진우;김찬영
    • Textile Coloration and Finishing
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    • v.1 no.1
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    • pp.19-25
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    • 1989
  • In past, dye diffusion and dyeing rate in fibers have been emphasized in dyeing phenomena. However, in the light of the properties of colloids in the surface of disperse phase and dispersion, there exist specific characters such as adsorption or electric double layer, which seems to play important roles in determining the physiochemical properties in the dyeing system. Electrostatic bonding, hydrogen bonding and Van der Waals adsorption are common in dyeing as well as covalent bonding. Particularly, electrostatic bonding is premised on the existance of ionic radicals in fibers. The present study was aimed to clarify the electrokinetic phenomena of dyeing through the role of electric double layer by ion in amphoteric fibers with different ionic effects under different pH. Spectrophotometric analysis method was used to compare dyeing condition of surface, which can be detected by electrokinetic phenomena and the inner of fibers after deceleration of dyed fibers. Nylon and wool, the typical amphoteric fibers were dyed with monoazo acid dyes such as C.I. Acid Orange 20, and C.I. Acid Orange 10. Various combinations were prepared by combining pH, temperature and dye concentration, in order to generate streaming electric potential which were measured by microvolt meter and specific conductivity meter. The results were transformed to zeta potential by Helmholtz-Smoluchowski formular and to surface electric charge density by Suzawa formular, surface dye amount, and effective surface area of fibers. The amount of dyes of inner fibers were also measured by the Lambert-Beer’s law. The main results obtained are as follows. 1. By measuring zeta pontential, it was possible to detect the dyeing mechanism, surface charge density, surface dye amount and effective surface area concerning dye adsorption of the amphoteric fibers. 2. Zeta pontential increases in negative at low pH and high dye concentration in the process of dyeing. This implied that there existed ionic bond formation in the dyeing mechanism between acid dyes and amphoteric fibers. 3. Dibasic acid dye had little changing rate in zeta potential due to the difference in solubility of dye and in number of dissociated ions per dye molecule to bond with amino radicals of amphoteric fibers. The dye adsorption of mono basic acid dye was higher than that of dibasic acid dye. 4. The effective surface areas concerning dyeing were $6.3E+05\;cm^2/g$ in nylon, $1.6E+07\;cm^2/g$ in wool fiber being higher order of wool then nylon.

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An Analysis of News Report Characteristics on Archives & Records Management for the Press in Korea: Based on 1999~2018 News Big Data (뉴스 빅데이터를 이용한 우리나라 언론의 기록관리 분야 보도 특성 분석: 1999~2018 뉴스를 중심으로)

  • Han, Seunghee
    • Journal of the Korean Society for information Management
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    • v.35 no.3
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    • pp.41-75
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    • 2018
  • The purpose of this study is to analyze the characteristics of Korean media on the topic of archives & records management based on time-series analysis. In this study, from January, 1999 to June, 2018, 4,680 news articles on archives & records management topics were extracted from BigKinds. In order to examine the characteristics of the media coverage on the archives & records management topic, this study was analyzed to the difference of the press coverage by period, subject, and type of the media. In addition, this study was conducted word-frequency based content analysis and semantic network analysis to investigate the content characteristics of media on the subject. Based on these results, this study was analyzed to the differences of media coverage by period, subject, and type of media. As a result, the news in the field of records management showed that there was a difference in the amount of news coverage and news contents by period, subject, and type of media. The amount of news coverage began to increase after the Presidential Records Management Act was enacted in 2007, and the largest amount of news was reported in 2013. Daily newspapers and financial newspapers reported the largest amount of news. As a result of analyzing news reports, during the first 10 years after 1999, news topics were formed around the issues arising from the application and diffusion process of the concept of archives & records management. However, since the enactment of the Presidential Records Management Act, archives & records management has become a major factor in political and social issues, and a large amount of political and social news has been reported.

The "open incubation model": deriving community-driven value and innovation in the incubation process

  • Xenia, Ziouvelou;Eri, Giannaka;Raimund, Brochler
    • World Technopolis Review
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    • v.4 no.1
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    • pp.11-22
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    • 2015
  • Globalization, increasing technological advancements and dynamic knowledge diffusion are moving our world closer together at a unique scale and pace. At the same time, our rapidly changing society is confronted with major challenges ranging from demographic to economic ones; challenges that necessitate highly innovative solutions, forcing us to reconsider the way that we actually innovate and create shared value. As such the linear, centralized innovation models of the past need to be replaced with new approaches; approaches that are based upon an open and collaborative, global network perspective where all innovation actors strategically network and collaborate, openly distribute their ideas and co-innovate/co-create in a global context utilizing our society's full innovation potential (Innovation 4.0 - Open Innovation 2.0). These emerging innovation paradigms create "an opportunity for a new entrepreneurial renaissance which can drive a Cambrian like explosion of sustainable wealth creation" (Curley 2013). Thus, in order to materialize this entrepreneurial renaissance, it is critical not only to value but also to actively employ this new innovation paradigms so as to derive community-driven shared value that stems from global innovation networks. This paper argues that there is a gap in existing business incubation model that needs to be filled, in that the innovation and entrepreneurship community cannot afford to ignore the emerging innovation paradigms and rely upon closed incubation models but has to adopt an "open incubation" (Ziouvelou 2013). The open incubation model is based on the principles of open innovation, crowdsourcing and co-creation of shared value and enables individual users and innovation stakeholders to strategically network, find collaborators and partners, co-create ideas and prototypes, share their ideas/prototypes and utilize the wisdom of the crowd to assess the value of these project ideas/prototypes, while at the same time find connections/partners, business and technical information, knowledge on start-up related topics, online tools, online content, open data and open educational material and most importantly access to capital and crowd-funding. By introducing a new incubation phase, namely the "interest phase", open incubation bridges the gap between entrepreneurial need and action and addresses the wantpreneurial needs during the innovation conception phase. In this context one such ecosystem that aligns fully with the open incubation model and theoretical approach, is the VOICE ecosystem. VOICE is an international, community-driven innovation and entrepreneurship ecosystem based on open innovation, crowdsourcing and co-creation principles that has no physical location as opposed to traditional business incubators. VOICE aims to tap into the collective intelligence of the crowd and turn their entrepreneurial interest or need into a collaborative project that will result into a prototype and to a successful "crowd-venture".

Knowledge Production Function in South Korea : An Empirical Analysis (우리나라 지식생산함수 : 실증분석)

  • Cho, Sang-Sup;Jung, Dong-Jin
    • Journal of Korea Technology Innovation Society
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    • v.10 no.3
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    • pp.383-405
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    • 2007
  • In this paper we estimate knowledge production function for 15 South Korean industry sectors using panel data. To accommodate the influence of inter-sectoral interactions on the creation of knowledge, we estimate parameters for related knowledge production functions using the Dynamic Seemingly Unrelated Regression(DSUR) model proposed by Mark et al. (2005). We find the elasticity of knowledge production with respect to the size of research staff to be 0.25 and that with respect to the existing stock of knowledge to be 0.35. The fact that the elasticity of new knowledge creation with regard to the existing knowledge stock is below 1 in South Korea corroborates the view that the rate of long-term growth of her economy is chiefly determined by the elasticity related to production functions of goods and services and the rate of population growth, and that her government policy, to ensure a continued growth for the Korean economy, must shift the focus of R&D policies from the current direct intervention-centered model to one consisting of indirect measures, namely supporting knowledge management and diffusion and the creation of a knowledge sharing system. In terms of R&D policy implications it could be consider that the national knowledge production system should strengthen the cumulative process of knowledge accumulation and population for research and development. Our country R&D policy, also, need to adopt a global approach to increase knowledge stock at the highest levels of a country.

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The innovation diffusion and neighbors in the 4th wave through Dubai-city (두바이 도시혁신에 따른 주변국가의 4차산업 혁신확산)

  • Seo, Dae-Sung;Kim, Dong-Hwa
    • The Journal of Industrial Distribution & Business
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    • v.9 no.12
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    • pp.55-61
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    • 2018
  • Purpose - It suggests that making a policy and strategies for a way of Dubai has a strong priority strategy on science and technology by using much oil dollars to prepare risk when oil dollar's decrease. This has been now investigated how the leading innovator has changed the periphery countries. Research design, data, and methodology - Analyze policy, status, what other neighbouring Middle East countries also want to benchmark a successful case of a leading Dubai strategy. Higher manpower is needed absolutely to develop S&T. and etc. Dubai and Arab countries establish university to nurture as well as invite the talented manpower from overseas to recover deficient manpower. Dubai built totally academy city and invited branch of the overseas famous university, and Saudi Arabia built university(KAUST) and invite faculty and support good scholarship for students. Abrab countries especially, This is studied the process of differentiating and integrating the migrant workers of these cities into the globalized cities. This has resulted in large-scale employment for foreign and local companies in these cities and the spread of science and innovation. Results - Dubai supports venture or SMEs by using a strong priority strategy and attracts foreigner's investor, with which the neighbouring countries have been preparing together for 4th wave. It demonstrates that the gravitational model has been activated from neighboring countries of innovation science to create Dubai's hub. The maturity of long-term urban innovation is related to innovation capability through the national response and review. As a result, the flow of skilled international migration has been localized because of the mutual intersection with the local employment structure, and the development has spread as it spreads to neighboring countries. Conclusion - For the exploiting of new Distribution market in the neighbouring countries, Middle East countries' a strong priority strategy on S&T and education system give an influence on economic situation of the 4th wave in the world and world order of leading by USA, Japan, or EU, and etc. This is due to the creation of clusters in the form of SEZs, friendly industrial policies and world-class infrastructure and innovation development. Its neighbours benchmark the cases of distribution of science innovation and centralizes the surrounding people.