• 기술경영경제학회:학술대회논문집
• /
• 기술경영경제학회 2003년도 제22회 동계학술발표회 논문집
• /
• pp.173-190
• /
• 2003

수요예측은 국가와 기업의 전략수립과 효율적인 자원활용에 있어서 필수적인 사전기획요소이다. 본 논문은 이산선택모델과 확산모델을 복합적으로 고려하여 다세대 제품의 수요를 예측하였다. 이산선택모델은 정적인 관점에서 소비자들의 제품에 대한 평가를 분석하는 모델이다. 본 논문에서는 이러한 이산선택모델에 수요의 동적인 변화양상을 고려할 수 있는 확산모델을 결합하였다. 실증분석으로서 1999년에서 2005년까지의 세계 DRAM시장 수요를 예측하였다. 또한, DRAM의 가격과 기억용량에 대해 '무어의 법칙' 과 '학습곡선'을 각각 적용한 기술예측을 시도하였으며, 이를 바탕으로 보다 정교한 예측모델을 전개하였다. 제시된 모델은 산업수준의 자료를 이용하였으므로, 이산선택모델을 inversion 하여 분석을 시도하였다. 이를 통해 기존세대의 DRAM 제품에 대한 수요뿐만 아니라, 새로운 세대의 DRAM 제품에 대한 수요를 비교적 정확히 예측할 수 있었다.

• 자원환경지질
• /
• 제26권3호
• /
• pp.421-429
• /
• 1993

Dissolution reactions of chemical grade zinc sulfide and natural sphalerite were studied in ferric chloride solution as an oxidant. To enhance the leaching reaction, ultrasonic technique was employed in this investigation. For the reaction with pure zinc sulfide, chemical reaction was the rate limiting step in the range of low conversion irrespective of applying ultrasonic wave. And the diffusion through liquid film instead of diffusion through product layer of free sulfur was the rate determining step because ultrasonic vibration removes the product from reaction zone. In the case of sphalerite with the ultrasonic vibrator, it was found that inert mineral layer diffusion was the rate determining step, in which the elemental sulfurs formed were removed by the ultrasonic action. Experimental results showed that the ultrasonic technique proved to be the methods which can significants improve the leaching performance.

• 한국정보시스템학회지:정보시스템연구
• /
• 제14권2호
• /
• pp.257-276
• /
• 2005

This study adopts diffusion of innovation theory and analyses product life cycle on two different information communication technology (ICT) products. One is telematics located on introduction and the other one is MP3 located on maturity. The analytical results were mixed. ordinary least square (OLS) result showed that adoption of MP3 player is affected by white noise error ($\varepsilon$) and telematics is influenced by innovation effect (p coefficient) rather than imitation effect (q coefficient) or white noise error. However, nonlinear least square (NLS) result showed that adoption of MP3 player is affected by imitation effect (q coefficient) rather than innovation effect (p coefficient). In addition, the ratio of imitation effect/innovation effect of MP3 player is larger than that of telematics.

• 한국기계가공학회지
• /
• 제19권3호
• /
• pp.92-98
• /
• 2020

In this study, an injection mold with conformal cooling channels was designed and manufactured for use in the production of a thick plastic cosmetic container that required high gloss surfaces. A cooling analysis verified the design of the conformal cooling channel for the cosmetic container, and also showed that the cooling efficiency was superior to that of the straight cooling channel. Slide cores designed with the conformal cooling channel were manufactured using the Layers Parting method and vacuum diffusion bonding. Subsequent test injection and quality inspection showed no problem in the appearance and dimensional accuracy of the produced product. The cycle time for product production was about 110 seconds, sufficient for mass production.

• Natural Product Sciences
• /
• 제14권1호
• /
• pp.32-36
• /
• 2008

The antimicrobial activity of seventy five ethanol extracts obtained from 67 different kinds of plant species of the Mongolian flora were evaluated by means of the disc diffusion method against five species of microorganisms, Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, Micrococcus luteus and Pseudomonas aeruginosa. Among the plant extracts examined, 34 kinds of extracts demonstrated significant antibacterial activity against one or more species of microorganisms, respectively. Especially, the root extract of Paeonia anomala, the whole herb extract of Myricaria alopecuroides, the whole herb extract of comarum zalesovianum, the whole herb extract of Agrimonia pilosa and some other plant extracts demonstrated a particularly potent antimicrobial activity. The ethylacetate fractions obtained from the whole herb extract of Myricaria alopecuroides and from those of Sedum aizoon, Paeonia anomala, Sedum hybridum and Dasiphora fruticosa exhibited a particularly potent antibacterial activity especially against Staphylococcus aureus and Micrococcus luteus.

• 한국경영과학회지
• /
• 제42권1호
• /
• pp.29-41
• /
• 2017

Korea is expected to become a super-aged society by 2050. Given an aging population and the increasing pressure for the early retirement, a sufficient social safety net for elderly population becomes important. The Korean government introduced public reverse mortgage program in 2007, which is a product for aging seniors and the elderly, The number of reverse mortgage subscribers has also steadily grown. The demand continues to grow, but the reverse mortgage over a long period of time is a highly uncertain and risky product in the position of guarantee or lending institution. Thus, suitable demand prediction of the reverse mortgage subscribers is necessary for stable and sustainable operation. This study uses a Bass diffusion model to forecast the long-term demand for reverse mortgage and provides insight into reverse mortgage by forecasting demand for stability and substantiality of the loan product. We represent the projections of new subscribers on the basis of the data obtained from Korea Housing Finance Corporation. Results show that potential market size of Korean reverse mortgage reaches approximately 760,000-1,160,000 households by 2020. We validate the results by comparing the estimate of the cumulative number of subscribers with that found in literature.

• 펄프종이기술
• /
• 제30권1호
• /
• pp.59-70
• /
• 1998

A steady-state molecular diffusion experiment was conducted to evaluate the water vapor proof properties of paper Handsheets prepared from unbleached Itraft pulps(UKP) and old newspapers(ONP) and four different types of polymer-laminated white duplex board were tested under appropriate standard conditions. The diffusivity was determined on the basis of the Fickean first law. Results obtained from this study can be summarized as follows ; 1. The diffusivity data for handsheets showed about $10^{-5}cm^2/min$. whereas polymer-laminated paperboards had remarkably improved water-vapor resistance with about $10^3 to 10^4$ times lower diffusivity : 2. Sheet basis weight, wet-swelling and sizing degree had little influence on the diffusivity of paper; 3 Linear relationship existed between sheet density and diffusivity, and, 4. Highly sfgnificant linear relationship could be observed between diffusivity and Darcy s gas permeability. Results indicate that diffusivity, an intrinsic property of paper, can provide a valuable information for precise evaluation and improved quality control of water-vapor proof properties of paper.

• 디지털융복합연구
• /
• 제6권2호
• /
• pp.55-64
• /
• 2008

The Internet possesses not only features of mass media but also features of word of mouth communication. Communication channel is considered as one of most important variables in diffusion process. In this paper, we examined functionality of technology diffusion on the Internet through the use of meta tags. We have measured the coefficients of the Bass diffusion model which has been well-established in new product diffusion. This research shows that the Bass model is appropriate for describing technology diffusion on the Internet. The external influence as represented by the coefficient of innovation was found to be much smaller while the internal influence dominates in all meta tag diffusion. In meta tag diffusion, the internal influence as represented by the coefficient of imitation was increased at least twice bigger than that of consumer durables and information technology. Collecting necessary data in social sciences research can be a burden. This research shows that it can be alleviated through the use of software agents over the Internet. The research made use of software agents for collecting longitudinal data from publicly accessible archive such as Archive.org.

• 디지털융복합연구
• /
• 제12권3호
• /
• pp.141-147
• /
• 2014

확산모형은 시장의 예측이나 그 방법론의 연구를 위해 마케팅에서 광범위하게 다뤄졌을 뿐 아니라, 경제학에서도 다양하게 활용되어 왔다. 특히 Bass 모형은 Rogers의 혁신확산 및 수명주기이론을 간단한 수리적 모형으로 표현할 수 있기에 혁신적 신제품의 채택과 확산을 설명하는데 널리 활용되었다. 그럼에도 불구, 확산모형은 '산업의 쌀' 이라 일컬어지는 반도체의 수요예측에 일부 선도적 연구를 제외하고는 활용된 바 없다. 이에 Bass 모형에서 진일보한 비선형회귀 접근법 확산모형을 활용, 전력반도체 중 전기전자기구의 필수 스위치로 채택되는 MOSFET의 수요를 추정하여 수명주기를 예측하고 그 과정을 설명함으로써 산업관계자는 물론 반도체와 전기전자산업 정책입안자에게 중요한 시사점을 전달하고자 한다.

• 대한산업공학회지
• /
• 제13권1호
• /
• pp.25-29
• /
• 1987

When the historical data are available, the diffusion model, which describes the time pattern of the adoption process of a new product or technology or service, has been used as a reasonable predictor in the telecommunication demand forecasting area. This paper shows that the diffusion model is applicable when the historical data are not available. The model used is in the form of a "logistic" function. The parameters of the function are estimated using the questionnaire and the historical data of reference products. From the questionnaire, an initial and an upper limit long run value of the market share are estimated, and the diffusion time to the upper limit value is determined by the relation between the investment and the utility.