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81.
Jiyeon RyuAuthor Vitae Soon Cheon ByeonAuthor Vitae 《Technological Forecasting and Social Change》2011,78(6):1049-1059
Technology has been the driving force of development for knowledge-based economies. As competition in technology innovation among nations becomes more intense, there is a growing need for improved judgment, evaluation and prediction of scientific technology capacity in order to enhance national competitiveness. Until now, a country's technology level has been evaluated on a relative basis by comparing it with that of the country with the world's best technology. However, this kind of static methodology makes the interpretation of results unclear and makes time series analysis difficult. One of the most important limitations of this methodology is that it cannot be used to establish a strategy to improve the technology level. This paper examines the methodological problems of technology level evaluation and develops a dynamic methodology by applying the technology growth curve model. We also analyze the real technology level by using a new model application and review the relevance of this method. Finally, we discuss how to use the results in order to create a dynamic technology strategy. 相似文献
82.
Luiz C.M. Miranda C.A.S. LimaAuthor vitae 《Technological Forecasting and Social Change》2011,78(8):1445-1470
Logistic and power law methodologies for both retrospective and prospective analyses of extended time series describing evolutionary growth processes, in environments with finite resources, are confronted. While power laws may eventually apply only to the early stages of said growth process, the Allee logistic model seems applicable over the entire span of a long range process. On applying the Allee logistic model to both the world population and the world gross domestic product time series, from 1 to 2008 AD, a projection was obtained that along the next few decades the world should experience a new economic boom phase with the world GDP peaking around the year 2020 and proceeding from then on towards a saturation value of about 142 trillion international dollars, while the world population should reach 8.9 billion people by 2050. These results were then used to forecast the behavior of the supply and consumption of energy and food, two of the main commodities that drive the world system. Our findings suggest that unless the currently prevailing focus on economic growth is changed into that of sustainable prosperity, human society may run into a period of serious economical and social struggles with unpredictable political consequences. 相似文献
83.
Clive-Steven CurranAuthor Vitae Jens LekerAuthor Vitae 《Technological Forecasting and Social Change》2011,78(2):256-273
The blurring of boundaries between hitherto distinct scientific disciplines, technologies or markets is a common and powerful phenomenon. Concentrating on monitoring convergence through patent indicators, we discuss convergence with examples from the area of Nutraceuticals and Functional Foods (NFF)/Cosmeceuticals as well as information technologies, consumer electronics, and telecommunications (ICT). We analyze 7455 scientific and patent references on phytosterols with the aid of SciFinder Scholar and 3836 documents employing STN AnaVist. Furthermore, we test an IPC co-classification based approach on 859,469 ICT-related and 341,846 NFF-related patents. Our results show clear indications for convergence and a proof of principle for our monitoring concept. Academics may better evaluate environmental parameters, like cases of convergence, influencing companies' actions. Implications for practitioners are based on a more reliable assessment prior to the forming of strategic alliances or mergers and acquisitions. This could help avoid costly adventures such as the mergers and acquisitions seen in ICT. 相似文献
84.
Forecasting of electricity costs based on an enhanced gray-based learning model: A case study of renewable energy in Taiwan 总被引:1,自引:0,他引:1
Shun-Chung LeeAuthor Vitae Li-Hsing Shih Author Vitae 《Technological Forecasting and Social Change》2011,78(7):1242-1253
This work presents a novel gray-based cost efficiency (GCE) model that integrates the gray forecasting model into a two-factor cost efficiency curve model for renewable energy (RE) technologies and identifies the optimal forecasting model for power generation cost of RE technologies. The analytical framework of proposed GCE model improves short-term prediction of power generation cost, and can be applied during the early developmental stages for RE technologies. Empirical analysis is based on wind power data for Taiwan. Time lag of knowledge stock was simulated to represent the actual relationship between R&D expenditures and cost reductions in power generation by knowledge stock. Analytical results demonstrate the GCE model is a useful tool to quantify the influences of cost reductions in power generation. The implications of analytical results are that institutional policy instruments play an important role in RE technologies achieving cost reductions and market adoption. The proposed GCE model can be applied to all high-technology cases, and particularly to RE technologies. The study concludes by outlining the limitations of the proposed GCE model and directions for further research. 相似文献
85.
基于案例推理的非常规突发事件资源需求预测 总被引:2,自引:0,他引:2
近年来非常规突发事件频繁发生,严重危害了人民的生命财产安全,而如何及时预测灾害发生后的资源需求成为一个重要课题。文章提出了一种精确的预测方法,将模糊集理论,神经网络Hebb学习规则和多元线性回归与案例推理法相结合。这种方法很好地解决了非常规突发事件资源需求预测这类信息不完备、不精确问题,能够比较准确的作出资源的需求预测。该模型对灾害资源需求预测具有一定的参考价值。 相似文献
86.
混合门限自回归模型在长期水文预报中的应用 总被引:5,自引:0,他引:5
在长期水文预报中主要应用两类方法,它们是多元分析法和时间序列分析法,这两种方法各有其局限性;应用混合门限自回归模型模拟水文时间序列可以考虑诸多因素,能避免以上两方法的局限性,并在实践中得到检验. 相似文献
87.
基于灰色理论的中国人口空间分布模式预测 总被引:1,自引:0,他引:1
运用灰色理论对我国各个省市未来人口总量进行预测,并应用GIS的空间自相关理论和方法对未来人口空间分布模式做出预测。研究认为,从2005年到2020年中:北京、天津、江苏、上海、浙江等省市始终保持与周围省市人口密度的高高关联关系,围绕这些省市的省份区域形成了相对人口聚集区域,西部许多省份及东北几省与周围的省份人口密度是维持着低低关联模式。广东省始终保持与周围省市人口密度的高高关联关系,即本省只是单独形成了一个聚集点。2014年是我国人口空间分布格局变动较大的时期。 相似文献
88.
《International Journal of Forecasting》2020,36(4):1517-1530
This paper develops indicators of unstructured press information by exploiting word vector representations. A model is trained using a corpus covering 90 years of Wall Street Journal content. The information content of the indicators is assessed through business cycle forecast exercises. The vector representations can learn meaningful word associations that are exploited to construct indicators of uncertainty. In-sample and out-of-sample forecast exercises show that the indicators contain valuable information regarding future economic activity. The combination of indices associated with different subjective states (e.g., uncertainty, fear, pessimism) results in further gains in information content. The documented performance is unmatched by previous dictionary-based word counting techniques proposed in the literature. 相似文献
89.
90.
《International Journal of Forecasting》2020,36(2):684-694
This paper introduces a combination of asymmetry and extreme volatility effects in order to build superior extensions of the GARCH-MIDAS model for modeling and forecasting the stock volatility. Our in-sample results clearly verify that extreme shocks have a significant impact on the stock volatility and that the volatility can be influenced more by the asymmetry effect than by the extreme volatility effect in both the long and short term. Out-of-sample results with several robustness checks demonstrate that our proposed models can achieve better performances in forecasting the volatility. Furthermore, the improvement in predictive ability is attributed more strongly to the introduction of asymmetry and extreme volatility effects for the short-term volatility component. 相似文献