• Title/Summary/Keyword: Diffusion process

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An Empirical Study on the Factors Affecting Diffusion of Objeccl-Oriented Technology (객체지향 기술의 확산에 영향을 주는 요인에 관한 경험적 연구)

  • 이민화
    • The Journal of Information Systems
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    • v.10 no.1
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    • pp.97-126
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    • 2001
  • Object-orientation has been proposed as a promising software process innovation to improve software productivity and quality. It has not been understood clearly, however, what factors influences the diffusion of object-oriented technology in organizations. A research model was formulated and hypotheses were generated based on the literature of information technology implementation and software process innovation. To test the research hypotheses, a questionnaire survey was conducted. The results based on 121 responses from Korean companies revealed that project characteristics, use of external experts, and number of development projects are significantly related to the diffusion of object-oriented analysis and design and object-oriented programming. Innovation champion is positively related to the diffusion of object-oriented analysis and design, whereas it is not related to the diffusion of object-oriented programming language. Only project complexity was significantly related to the diffusion of visual programming language. On the other hand, organizational size was not significantly related to any object-oriented technology in this study.

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Improving the Algorithm of a Diffusion Filter U sing a Difference Network and Quantitative Analysis of Band Pass Characteristics (차분망을 이용한 확산필터 알고리즘의 개선 및 대역통과특성의 정량적 분석)

  • 허만택;남기곤;김재창;이종혁;김길중;윤태훈;박의열
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.7
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    • pp.163-172
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    • 1996
  • Recently, it was reported that gaussian distribution and difference of two gaussians (DOG) to have band pass characteristics can be generated by simple iterative processes of the diffusion networks. In this paper, we propose method of improved implementation of a diffusion filter which can reduce total runing time, and operate by simple algorithm in contrast to the latest diffusion filter. We rebuild the diffusion network to a difference network which can generate DOG independently. Different filter characteristics are obtained just by each diffusion process and difference process. Quantitative analysis shows that the center frequency and the selectivity of each filter channel can be varied independently. Also, it would requires smaller amount of hardwares than conventioanl method to build a filter bank.

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A Study on Adoption/Diffusion Models for New Product (신제품 수용$\cdot$확산모형에 관한 연구)

  • 김용준;박영근
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.10 no.16
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    • pp.149-158
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    • 1987
  • The Adoption/Diffusion of Innovations(New Product), a topic of study and research that has frown rapidly in the past few decades, deals with how a new product is adopted in a society. It is of high importance to marketing organizations because New Products must be brought out continuously in order to service. The purpose of this paper is to examine the Adoption/Diffusion Models for New product which will help to analyze the Adoption/Diffusion process of Adopters. There are a number of models that, with varying degrees of success, have been used to predict market acceptance of new product. In this paper, following types of new product Adoption/Diffusion Models was suggested. (1) Adoption Models : The Alternative Models of Adoption. The Rogers Model of the Innovation Decision Process. (2) Diffusion Models : First Purchase Models(Basic Models, Extension of the Basic Models), Repeat Purchase Models

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New Fabrication Method of $Ti:LiNbO_3$ Waveguide with Suppressed Out-Diffusion ($Li_2O$의 삼출이 없는 $LiNbO_3$ 광도파로의 제조방법)

  • 김상혁;김상국;조재철;최상삼
    • Korean Journal of Optics and Photonics
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    • v.2 no.3
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    • pp.149-152
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    • 1991
  • We report a new method of fabricating a Ti:LiNb03 waveguide with no out-diffusion by coating the waveguide with $SiO_2$ thin film. It was coated before diffusion process, and the $LiO_2$ out-diffusion was prevented in the diffusion process. We compare the near field patterns of the guided modes between the typical waveguide and the waveguide fabricated by new method proposed here.

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Effect of Process Temperature on the Sm2Fe17 Alloying Process During a Reduction-Diffusion Process Using Fe Nanopowder (Fe 나노분말을 사용한 환원-확산공정에서 Sm2Fe17 합금상형성에 미치는 공정온도의 영향)

  • Yun, Joon-Chul;Lee, Geon-Yong;Lee, Jai-Sung
    • Korean Journal of Metals and Materials
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    • v.48 no.11
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    • pp.995-1002
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    • 2010
  • This study investigated the effect of process temperature on the alloying process during synthesis of $Sm_2Fe_{17}$ powder from ball-milled samarium oxide ($Sm_2O_3$) powders and a solid reducing agent of calcium hydrides ($CaH_2$) using iron nanopowder (n-Fe powder) by a reduction-diffusion (R-D) process. The $n-Fe-Sm_2O_3-CaH_2$ mixed powders were subjected to heat treatment at $850{\sim}1100^{\circ}C$ in $Ar-H_2$ for 5 h. It was found that the iron nanopowders in the mixed powders are sintered below $850^{\circ}C$ during the R-D process and the $SmH_2$ is synthesized by a reduced Sm that combines with $H_2$ around $850^{\circ}C$. The results showed that $SmH_2$ is able to separate Sm and $H_2$ respectively depending on an increase in process temperature, and the formed $Sm_2Fe_{17}$ phase on the surface of the sintered Fe nanopowder agglomerated at temperatures of $950{\sim}1100^{\circ}C$ in this study. The formation of the $Sm_2Fe_{17}$ layer is mainly due to the diffusion reaction of Sm atoms into the sintered Fe nanopowder, which agglomerates above $950^{\circ}C$. We concluded that nanoscale $Sm_2Fe_{17}$ powder can be synthesized by controlling the diffusion depth using well-dispersed Fe nanopowders.

Crystalline Silicon Solar Cell with Selective Emitter Using One-step Diffusion Process (One-step diffusion으로 형성된 선택적 에미터 결정질 실리콘 태양전지에 관한 연구)

  • Jeong, Kyeong-Taek;Yang, O-Bong;Yu, Gwon-Jong;Lee, Jeong-Chul;Song, Hee-Eun
    • 한국태양에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.40-44
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    • 2011
  • Recent studies in crystalline silicon solar cell fabrication have been focused on high efficiency and low cost. However, the rising of the cost results in additional processes to approach high efficiency. The fabrication process also becomes complicated with additional technologies. In this paper, we studied the selective emitter formation with phosphorous paste to improve the conversion efficiency. Selective emitter formations like two-step diffusion or etch-back method require at least one more step compared in the conventional line since heavily and lightly doped area was needed to form separately.However,one-step diffusion process is the method diffusing heavily and lightly doped area at the same time only with additional screen-printing step. This study lays the foundation for the simple way to form the selective emitter.

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A Study on te Water Diffusion of Polymer-Modified Mortars in Drying Process (건조과정에 있어서 폴리머 시멘트 모르터의 수분확산에 관한 연구)

  • 조영국;소양섭
    • Magazine of the Korea Concrete Institute
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    • v.8 no.5
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    • pp.135-143
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    • 1996
  • Diffusion of water in hardened cement concrete and mortar influences on the dry shrinkage. creep. modulus of' elasticity, etc. In general, water loss through drying process in polymer-modified concrete and mortar is small compared with that of unmodified concrete and mortar due to the films formed by polymer as cement modifieder. The purpose of this study is to investigate the diffusion process of water in the polymer-modified mortars. The polymer-modified mortars using three polymer dispersions and epoxy resin are prepared with various polymer-cement ratios, and water diffusion coefficient of polymer-modified mortars according to inside water content is calculated. From the test results, the water diffusion coefficient of polymer modified mortars i s smaller than that of unmodified mortars and decreases with increasing polymer cement ratio.

Analysis of Diffusion Pattern in New Product and Services Based on Two-pieces Bass Model (신제품 및 서비스에 있어 이분조각 Bass모형에 의한 확산 패턴 분석)

  • Hong, Seok-Kee;Hong, Jung-Sik
    • IE interfaces
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    • v.23 no.4
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    • pp.337-348
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    • 2010
  • The Bass model is the most widely used model in research of new product diffusion because it presents a nice explanation on the diffusion process of new products. However, it has a limitation that its performance of fitness is lower as the available data become less and also, the diffusion curve is bell-shape and so, it can not represent the various diffusion patterns. Recently, a two-pieces Bass model is developed and applied to analyze diffusion of 10 products. The results are encouraging in terms of fitness. However, diffusion pattern is not dealt with in the paper. In this paper, analysis of diffusion pattern is in depth addressed in two-pieces Bass model. It is shown that the diffusion curves are divided into 3 types with respect to the peak adoption rate and each type is divided into 2 types further. Takeoff time of a diffusion process is analyzed by using the inflection point and regime-change time where it represents the point that imitation and innovation parameters change. Empirical studies for 68 products(28 domestic products and 40 USA products) are performed to analyze the diffusion pattern. Findings are that diffusion patterns of all products except 1 USA product show type I and regime-change time becomes shorter as the introduction time of the product is later in domestic products and regime-change time can be regarded as a takeoff time in 47% of total 68 products.

A NOTE ON NUMERICAL APPROACHES FOR HEAT-DIFFUSION EQUATION WITH HETEROGENEOUS MEDIA AND ITS APPLICATIONS

  • Seo, Sat byul
    • East Asian mathematical journal
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    • v.35 no.1
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    • pp.99-108
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    • 2019
  • In this paper, we introduce a numerical approach to solve heat-diffusion equation with discontinuous diffusion coefficients in the three dimensional rectangular domain. First, we study the support operator method and suggest a new method, the continuous velocity method. Further, we apply both methods to a diffusion process for neurotransmitter release in an individual synapse and compare their results.