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11.
Chi-Yo Huang Author Vitae Author Vitae 《Technological Forecasting and Social Change》2008,75(1):12-31
Product life cycle (PLC) prediction plays a crucial role in strategic planning and policy definition for high-technology products. Forecast methodologies which can predict PLCs accurately can help to achieve successful strategic decision-making, forecasting, and foresight activities in high-technology firms, research institutes, governments, and universities. Over the past few decades, even though analytic framework strategies have been proposed for production, marketing, R&D (research and development), and finance, aiming at each stage of PLCs, forecast methodologies with which to predict PLCs are few. The purpose of this research is to develop a novel forecast methodology to allow for predictions of product life time (PLT) and the annual shipment of products during the entire PLC of multiple generation products. A novel two-stage fuzzy piecewise regression analysis method is proposed in this paper. In the first stage, the product life-time of the specific generation to be analyzed will be predicted by the fuzzy piecewise regression line that is derived based upon the product life-time of earlier generations. In the second stage of the forecast methodology, the annual shipment of products of the specified generation will be predicted by deriving annual fuzzy regression lines for each generation, based upon the historical data on the earlier generations' products. An empirical study predicting the life-time and the annual shipment of the 16 Mb (Mega bit) DRAM (Dynamic Random Access Memory) PLC is illustrated to validate the analytical process. The results demonstrate that two-stage fuzzy piecewise regression analysis can predict multiple generation PLT and PLC precisely, thereby serving as a foundation for future strategic planning, policy definitions and foresights. 相似文献
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Borges del Rosal Africa San Luis Concepción Sánchez-Bruno Alfonso 《Quality and Quantity》2003,37(3):303-316
Quality &; Quantity - Cliff (1993) has proposed the use of a measure of effect size alternative to traditionalmean differences: δ {? = Pr(xi1 &;gt; xj2) - Pr(xi1 &;lt; xj2)}which,... 相似文献
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中国户口制度改革的理论分析 总被引:6,自引:0,他引:6
随着户籍制度改革的深化 ,从完全禁止户口迁移到数量限制政策 ,再到征收费用政策和放开小城镇入户限制的逐步放松户籍管制政策 ,对经济发展的贡献日益增加 ,损害逐渐减轻。我国放开小城镇户籍限制的改革放活了地方经济。我国户籍制度改革进程是由经济内生决定的 ,城市经济发展的需要推进着户籍制度的改革进程。那些放开户籍限制的城市也没有出现人们担心的问题。放开户籍限制不会构成对城市就业、住房、治安、交通的压力 ,反而创造了发展的契机。 相似文献
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This paper is devoted to studying optimal designs for estimating an extremal point of a multivariate quadratic regression model in the unit hyperball. The problem of estimating an extremal point is reduced to that of estimating certain parameters of a corresponding nonlinear (in parameters) regression model. For this reduced problem truncated locally D-optimal designs are found in an explicit form. The result is a generalization of the results of Fedorov and Müller (1997) for onedimensional quadratic regression function in the unit segment.
Received February 2002 相似文献
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We investigate how economic policy uncertainty (EPU) and geopolitical risks (GPR) impact Bitcoin volatility with respect to factors related to type and nationality of uncertainty, investigated period, relationship horizon and extreme conditions. Applying ARDL model and quantile regression for monthly data from August 2010 to September 2021, we reveal that June 2014 corresponds to a key date that marks a reversal in the investigated relationship. Furthermore, we show that the relationship between uncertainty and bitcoin volatility changes according to different factors. US uncertainty has short run effects on Bitcoin volatility, while China’s uncertainty has rather long run effects. Moreover, Bitcoin volatility responds in the same manner to US EPU and GPR, while, it responds differently to China's EPU and GPR. In extreme quantiles, we find that Bitcoin hedges against US EPU and GPR. Further, Bitcoin hedges against either individual or joint effects of US uncertainty, but not both. 相似文献
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民营旅行社在中国的发展 总被引:2,自引:0,他引:2
通过民营企业东星旅行社借助汉口国旅的“壳资源”进军出境旅游业务的事例,探讨民营资本向旅行社行业扩张时,面临的各种制度壁垒和其他困难,并联系中国加入世贸带来的机遇和挑战,对民营旅行社的发展和扩张提出了系列想法和建议。 相似文献
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从心身医学的角度,阐述冠状动脉硬化性心脏病的病因学,心理生物学机制及防治;对现代社区医疗卫生工作中的老年疾病的康复保健具有一定的指导意义。 相似文献