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81.
This paper estimates a forecasting equation for the hourly peak electricity demand one day in the future. The models incorporate deterministic influences such as holidays, stochastic influences such as average loads by building bivariate models, and exogenous influences such as the weather which is given a careful non-linear formulation. Out-of-sample comparisons are made using an additional year of data. 相似文献
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General systems formalizations of expert knowledge play a foundational role in the process of knowledge engineering of intelligent systems. Canonical definitions of systems (knowledge structures) which have been arrived at by a crossdisciplinary inductive modeling process are shown to be the basis for the modeling of certain generic categories of expert reasoning processes which are of current interest in knowledge engineering. The methodology for transforming the representation of knowledge expressed in general systems formalizations to the representation of that knowledge in expert systems is also developed. In particular, transformations from general systems formalizations into frames are presented. 相似文献
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C Bottex D Robert R Fontanges 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,284(19):1943-1946
An intranasal immunization with a A/PR8/34-isolated NA, protected mice as well as the whole virus and A/Hong Kong/1/68 virus against a subsequent infection with mice-adaptated A/PR8/34 strain. 相似文献
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Clements and Hendry (1993) proposed the Generalized Forecast Error Second Moment (GFESM) as an improvement to the Mean Square Error in comparing forecasting performance across data series. They based their conclusion on the fact that rankings based on GFESM remain unaltered if the series are linearly transformed. In this paper, we argue that this evaluation ignores other important criteria. Also, their conclusions were illustrated by a simulation study whose relationship to real data was not obvious. Thirdly, prior empirical studies show that the mean square error is an inappropriate measure to serve as a basis for comparison. This undermines the claims made for the GFESM. 相似文献
88.
L. Robert 《Cellular and molecular life sciences : CMLS》1981,37(10):1055-1058
Conclusion The brief summary of our present knowledge on the aging of intercellular matrix macromolecules shows the progress which has been made since the original important discovery of Verzár, but it also points out the very considerable gaps which still have to be filled by continued research efforts in this theoretically and practically important area. It is no secret to anyone that most of the disabling and killing diseases of advanced societies concern connective tissues: arteriosclerosis, diabetes, pulmonary obstructive lung diseases, osteoarticular diseases and cancer itself are all age-dependent, so-called aging diseases. The interaction between intercellular matrix and cancer cells plays an important role in the spreading of the tumors. For these other major diseases, the direct involvement of intercellular matrix is well documented. It is therefore hoped that a better grasp of the basic mechanisms involved in these diseases will help us to understand the difference between pathology and aging per se. 相似文献
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Biogenesis, maturation and aging of elastic tissue 总被引:1,自引:0,他引:1