• Title/Summary/Keyword: 확산 이론

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An Study of Demand Forecasting Methodology Based on Hype Cycle: The Case Study on Hybrid Cars (기대주기 분석을 활용한 수요예측 연구: 하이브리드 자동차의 사례를 중심으로)

  • Jun, Seung-Pyo
    • Journal of Korea Technology Innovation Society
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    • v.14 no.spc
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    • pp.1232-1255
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    • 2011
  • This paper proposes a model for demand forecasting that will require less effort in the process of utilizing the new product diffusion model while also allowing for more objective and timely application. Drawing upon the theoretical foundation provided by the hype cycle model and the consumer adoption model, this proposed model makes it possible to estimate the maximum market potential based solely on bibliometrics and the scale of the early market, thereby presenting a method for supplying the major parameters required for the Bass model. Upon analyzing the forecasting ability of this model by applying it to the case of the hybrid car market, the model was confirmed to be capable of successfully forecasting results similar in scale to the market potential deduced through various other objective sources of information, thus underscoring the potentials of utilizing this model. Moreover, even the hype cycle or the life cycle can be estimated through direct linkage with bibliometrics and the Bass model. In cases where the hype cycles of other models have been observed, the forecasting ability of this model was demonstrated through simple case studies. Since this proposed model yields a maximum market potential that can also be applied directly to other growth curve models, the model presented in the following paper provides new directions in the endeavor to forecast technology diffusion and identify promising technologies through bibliometrics.

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Nscreen Service User Typology Based on Use-Diffusion and Lifestyle (사용확산 및 라이프스타일에 따른 N스크린 서비스 이용자 유형화)

  • Park, Hyun Jung
    • The Journal of the Korea Contents Association
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    • v.15 no.2
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    • pp.444-454
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    • 2015
  • The purpose of this study is to investigate factors related to use-diffusion of Nscreen service as well as consumers' lifestyle and media usage of Nscreen service, which is fundamentally changing both the competitive landscape for business and the daily lives of consumers. The data of 1,524 consumers used in this study were drawn from the first Korea Media Panel Study in 2012 of Korea Information Society Development Institute. This study categorized adopters depending on the usage rate of contents and the variety of media platforms they used. Consumers using various media platforms enjoyed more categories of contents provided by Nscreen services. The variety of media platforms was useful in grouping users to explain the difference between the groups in terms of lifestyle activities. Based on the factor analysis and cluster analysis based on the consumers' lifestyle to find out different characteristics of each clusters, the result elicited some implications.

Characteristics of Charging and Collection of 10-nm-Class Ultrafine Nanoparticles in an Electrostatic Precipitator (전기집진기의 10 nm 급 초미세 나노입자의 하전 및 집진 특성)

  • Han, Bang-Woo;Kim, Hak-Joon;Kim, Yong-Jin;Song, Dong-Keun;Hong, Won-Seok;Shin, Wan-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.10
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    • pp.1013-1018
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    • 2011
  • The charging of 10-nm-class nanoparticles in an electrostatic precipitator (ESP) according to particle charging ratio has been investigated and compared to the diffusion effect of the nanoparticles. The competition between the charging probability and the diffusion loss effect determines the collection efficiency of nanoparticles in the ESP. The collection efficiency of nanoparticles decreased continuously with decreasing particle diameter. This indicates that the partial charging effect of 10-nm-class nanoparticles is more dominant than their diffusion loss effect in the ESP for nanoparticles in the particle size range of less than 10 nm. The charging ratios based on unipolar diffusion charging calculations were in good agreement with the experimental collection efficiencies for nanoparticles less than 10 nm in diameter.

Tracer Tests On Using Rhodamine-WT in Natural Streams (Rhodamine-WT을 이용한 자연하천에서의 추적자 실험)

  • Seo, Il-Won;Kim, Young-Do;Choi, Hwang-Jeong;Han, Eun-Jin;Mun, Hyun-Saing
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.194-194
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    • 2012
  • 본 연구에서는 자연하천에서 Rhodamine-WT를 이용하여 추적자 실험을 수행하고 이를 바탕으로 오염사고대응예측모델에 대한 검증을 실시하고자 하였다. 최근 국내에서는 다양한 형태와 규모의 수질오염사고가 매년 수십건 이상 발생하고 있으며, 따라서 수치모형 기반의 수질오염 사고 대응 예측시스템에 대한 높은 신뢰성이 요구되고 있다. 수질사고에 노출되어 있는 지표수를 각종 용수로서 안전하게 공급하기 위해서는 정확한 수질예측이 필수적이며, 이를 위해서 수십 년간 연구되어 온 수질모델을 오염사고 대응예측시스템에 적합하도록 정확성과 신뢰성을 갖추기 위한 연구가 진행되어야 한다. 수치 모형을 이용한 물질의 이송 및 확산 모의에서는 오염물질 도달시간과 확산 농도를 결정하는 것이 가장 중요한 요소이므로 이송 및 확산 모의에 대한 검증 기법 개발 및 적용이 필요하다. 본 연구에서는 낙동강수계 지류하천인 감천에서 추적자 실험을 4회 실시하여 측정한 수리량과 농도 실측치를 이용하여 분산계수를 종 횡분산계수 산정이 가능한 2차원 유관추적법을 적용하여 산정하였다. 각 단면에 유속은 ADV-3차원 유속계인 Flow-Tracker를 사용하여 도섭으로 측정하였으며 하천의 흐름 방향의 직각으로 측선을 설치하고 펌프를 이용하여 채수를 한 다음 Rhodamie WT의 농도를 측정하였으며 측선의 위치 보정은 GPS를 통하여 보정하였다. 측정 자료를 이용하여 2차원 유관추적법으로 분산계수를 산정한 결과 각각의 측선에 따라서 다소 차이가 발생하였으며, 일부 구간에서는 이론식으로 계산한 분산계수와 근사한 값이 나타났다. 이는 사주가 매우 발달하고 만곡이 많은 실험구간의 특성상 Elder와 Fischer 식으로 계산한 값과 차이가 발생할 가능성이 높은 구간이기 때문인 것으로 판단된다. 또한 하폭에 대한 수심비가 커질수록 분산계수도 증가하고 평균유속에 대한 전단유속에 비에 비례하는 것으로 나타났다.

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Analysis of Soot Particle Morphology Using Rayleigh Debye Gans Scattering Theory (RDG 산란 이론을 이용한 그을음 탄소 입자의 형상 분석)

  • Seo, Hyoungseock;Kim, Kibum
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.9
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    • pp.641-646
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    • 2016
  • Soot particles generated by fossil fuel combustion normally have fractal morphology with aggregates consisting of small spherical particles. Thus, Rayleigh or Mie elastic light scattering theory is not feasible for determining the fractal properties of soot aggregates. This paper describes a detailed process for applying Rayleigh-Debye Gans (RDG) scattering theory to effectively extract the morphological properties of any nano-scale particles. The fractal geometry of soot aggregates produced from an isooctane diffusion flame was observed using ex situ transmission electron microscopy (TEM) after thermophoretic sampling. RDG scattering theory was then used to analyze their fractal morphology, and various properties were calculated, such as the diameter of individual soot particles, number density, and volume fraction. The results show indiscernible changes during the soot growth process, but a distinct decreasing trend was observed in the soot oxidation process. The fractal dimension of the soot aggregates was determined to be around 1.82, which is in good agreement with that produced for other types of fuel. Thus, it can be concluded that the value of the fractal dimension is independent of the fuel type.

Experimental, Theoretical and Numerical Studies for Concentrations and Velocities of Gas Jets (가스 제트 누출의 농도 및 속도에 대한 실험, 이론 및 수치해석 연구)

  • Bang, Boo-Hyoung;Kim, Hong-Min;Kim, Sung-Hoon;Lee, Keun-Won
    • Journal of the Korean Institute of Gas
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    • v.26 no.1
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    • pp.20-26
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    • 2022
  • The results of experimental, theoretical, and numerical analysis were compared regarding the concentrations and velocities of flammable gas jets generated by pressurized leakage of methane gas. The concentration was measured through experiments for the jet dispersion process, and the velocities was calculated by applying the self-similarity theory. And the velocities and concentrations were calculated using CFD tools - FLACS and CFX- compared with the results. The difference between self-similarity model and CFD is due to the buoyancy term, which increases as the distance from a leak source increases. The results are compared with dimensionless parameters using the leak source radius and velocity components along the leak axis.

Analysis of Shear Flow Dispersion Using Sequential Mixing Model (순차혼합모형에 의한 전단류 분산 해석)

  • Seo, Il-Won;Son, Eun-Woo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.991-995
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    • 2005
  • 본 연구에서는 1차원 이송-분산 과정을 연구하고 전단류 흐름 및 분산거동에 있어 Taylor 이론의 핵심이라 할 수 있는 '종방향 이송과 횡방향 확산의 균형'을 기본 개념으로 하여, 이송과 확산을 분리하여 이 두 과정이 순차적으로 발생한다는 가정에 의거한 순차혼합모형을 제시하였다. 본 모형에서는 가상의 하천을 여러 개의 행과 종방향 거리를 길이가 일정한 구획으로 나누어 연속적인 분산과정을 이산적인 형태로 나타낼 수 있게 하고, 횡방향 유속분포에 따라 각 행에 각기 다른 유속을 할당한다. 오염물질은 하폭방향 선오염원으로 원점에 순간주입되며, 주어진 혼합시간 $t_m$ 동안 각 행의 오염물질들이 각자에 할당된 유속을 따라 진행하고 진행이 끝난 후 횡방향 확산이 순간적으로 이루어진다. 횡방향 확산은 횡방향으로 완전하게 일어남을 가정하여, 횡방향 확산이 끝나면 각 열에서의 농도 평균값이 할당된다. 이러한 혼합시간 $t_m$ 동안의 순차적인 이송-확산 과정이 반복되면서 오염물질의 분산이 일어나며, 농도 분포 그래프를 그릴 수 있게 된다. 순차혼합모형을 가상의 직선하천에 적용하여 종분산계수를 유도하였는데, 본 연구에서 유도된 종분산계순식은 Fischer.가 제안한 식과 유사한 형태로 나타남을 알 수 있었다. 본 모형에서 계산된 농도분포 곡선을 해석해와 비교한 결과,두 곡선이 적절히 일치함을 확인할 수 있었으며 해석해와의 비교를 통해 종분산계수 K가 혼합시간 $t_m$과 선형관계임을 확인할 수 있었다. 수심대하폭비에 따라 각기 다른 유속분포에 적용하여 종분산계수 K가 유속편차강도의 제곱에 비례관계에 있음이 밝힐 수 있었다. 수압은 $4.69kg/cm^2$으로 나타났다. 밸브 개폐도가 $100\%$일 때가 밸브를 $60\%$$80\%$ 개폐시켰을 때보다 $0.3kg/cm^2,\;0.29kg/cm^2$ 낮게 나타나 밸브를 전체 개방 했을 때 관로내의 수압이 상수설계기준에 적합한 수압을 유지함을 알 수 있다. 상수관로 설계 기준에서는 관로내 수압을 $1.5\~4.0kg/cm^2$으로 나타내고 있는데 $6kg/cm^2$보다 과수압을 나타내는 경우가 $100\%$로 밸브를 개방하였을 때보다 $60\%,\;80\%$ 개방하였을 때가 더 빈번히 발생하고 있으므로 대상지역의 밸브 개폐는 $100\%$ 개방하는 것이 선계기준에 적합한 것으로 나타났다. 밸브 개폐에 따른 수압 변화를 모의한 결과 밸브 개폐도를 적절히 유지하여 필요수량의 확보 및 누수방지대책에 활용할 수 있을 것으로 판단된다.8R(mm)(r^2=0.84)$로 지수적으로 증가하는 경향을 나타내었다. 유거수량은 토성별로 양토를 1.0으로 기준할 때 사양토가 0.86으로 가장 작았고, 식양토 1.09, 식토 1.15로 평가되어 침투수에 비해 토성별 차이가 크게 나타났다. 이는 토성이 세립질일 수록 유거수의 저항이 작기 때문으로 생각된다. 경사에 따라서는 경사도가 증가할수록 증가하였으며 $10\% 경사일 때를 기준으로 $Ro(mm)=Ro_{10}{\times}0.797{\times}e^{-0.021s(\%)}$

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A Theoretical Framework for the Study of the Affecting Factors on the Internet Technology Adoption at U.S Banks (미국은행의 인터넷 기술 도입요인 분석을 위한 이론적인 틀에 관한 연구)

  • 장용택;유상진
    • Journal of Korea Society of Industrial Information Systems
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    • v.5 no.3
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    • pp.94-110
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    • 2000
  • While most of the previous information technology adoption and diffusion researches focus the critical factors not on the organizational perspective but on the individual perspective based on the various reasons such as informational characteristics. This paper will try to analysis the adoption and diffusion factors of the Internet related technologies based on the organizational perspective. Nowadays, in especially, the evolving and fast diffusing Internet related technologies and the flourishing e-commerce applications pressure retail banks that prepare the new types of online payment systems to maintain their existing and new customer relationship and compete with their potential competitors in the coming market environments. In addition, while most previous researches only focus on the adoption of new information technologies, this paper not only analysis the adoption of innovational technology but also analysis the diffusion process in an organization, which encourage practitioners and researchers to reveal more detail and practical analysis of the innovational technology adoption and diffusion process in ann organizational setting. Based on the previous researches, there are several factor-category will be selected for this research: 1) organizational factor, 2) within banking industry factor, 3) non-banking industry factor, 4) customer acceptance factor, 5) government factor, and 6) the functionality of e-commerce systems factor. Finally, in this study, we assumed that the more sophisticated e-commerce adopting banks provide the more broad range of banking services in general. Thus, we develop the extended integrated technology diffusion model to provide empirical evidences to distinguish between adopters and non-adopters and explain the diffusion levels of e-commerce using the level of services provided via Internet to the customer in retail bank industry.

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Studies on the Extraction Rate of Oil from Sardine, Sardinops melanosticta (정어리 지질의 추출속도에 관한 연구)

  • YANG Hyun-Seok;LEE Keun-Tai;BYUN Dae-Seok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.1
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    • pp.40-46
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    • 1984
  • The extraction ratio of oil using solvent from the muscle of sardine, Sardinops melanosticta, was studied. The results were critically evaluated in the light of the theory of oil diffusion in a porous solid model. In addition the effect of temperature and moisture on the extraction rate was examined. Sardine muscle was prepared in a manner to meet the conditions required by the diffusion theory from Fick's law. The results of the model were well coincidenced to the theory derived from Fick's law. Diffusion constants at the direction to muscle fiber($D_1$) and at direction perpendicular to fiber($D_2=D_3$) when extracted at $45^{\circ}C$ were $8.16{\times}10^{-8}cm^2/sec\;and\;4.12{\times}10^{-8}cm^2/sec$, respectivly. The extraction rate was linearly propotional to absolute temperature(T) by eleventh power under the constant condition of moisture contents and muscle size. A comparison of the experiments with the highest($74.22\%$) and the lowest ($32.48\%$) moisture indicated that difference of $1\%$ in moisture contents caused to change the slope(K) of the extraction curve $0.53{\times}10^{-6}sec^{-1}$ approximately.

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A Study on the Factors Influencing Crowdfunding by Shared Value and Communication (가치공유와 커뮤니케이션이 크라우드펀딩 참여의도에 미치는 영향에 관한 연구)

  • Yu, Yun-hyeong;Choi, Myung-gil
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.5
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    • pp.113-127
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    • 2020
  • Based on the social exchange theory and innovation diffusion theory, this study is to identify the correlation between factors influencing investor's funding intention in crowdfunding and to analyze moderating effect of trust in the relationship of shared value, communication and individual innovation. The purpose of this study is to consider the funding trends of crowdfunding investors from a personal point of view through the results of the study and to help fundraiser of crowdfunding establish specifically strategies for financing. In order to conduct empirical analysis, an online survey was conducted on people who had participated in crowdfunding, and a total of 228 questionnaires were collected and a total of 186 responses were finally analyzed, excluding outliers. For data analysis, structural equation model analysis was conducted using SPSS 26.0 and Smart PLS 3.0. The results of this study showed that shared value in the relationship between fundraiser and investors has a significant effect on the perceived risk. High level of communication between fundraiser and investors showed positive effects on the level of commitment of the crowdfunding project and the innovation of the individual investor. And commitment had a positive effect on the funding intention. According to the results of this research, trust has moderating effect only in relationship between shared value and perceived risk. It is significant that investors share the value of fundraiser together is a motivation factor to fund in crowdfunding and an opportunity to recognize the risk. Through this study, it is expected to utilize them in establishing strategies for start-ups and marketing plans to raise funds through crowdfunding and to empirically identify factors influencing the funding intention through individual levels of crowdfunding investors.