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51.
This paper uses monthly survey data for the G7 countries for the time period 1989–2007 to explore the link between expectations on nominal wages, prices and unemployment rates as suggested by the wage and price Phillips curves. Four major findings stand out. First, we find that survey participants trust in both types of Phillips curve relationships. Second, we find evidence in favor of nonlinearities in the price Phillips curve. Third, we take into account a kink in the price Phillips curve to indicate that the slope of the Phillips curve differs during the business cycle. We find strong evidence of this feature in the data which confirms recent theoretical discussions. Fourth, we employ our data to the expectations‐augmented Phillips curve model. The results suggest that professional forecasters adopt this model when forecasting macroeconomic variables. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
52.
Wang ZongjunInstitute of Systems Engineering. Huazhong University of Science Technology. Wuhan P. R. China 《系统工程与电子技术(英文版)》1993,(1)
There has been an increasing interest in integrating decision support systems (DSS) and expert systems (ES) to provide decision makers a more accessible, productive and domain-independent information and computing environment. This paper is aimed at designing a multiple expert systems integrated decision support system (MESIDSS) to enhance decision makers' ability in more complex cases. The basic framework, management system of multiple ESs, and functions of MESIDSS are presented. The applications of MESIDSS in large-scale decision making processes are discussed from the following aspects of problem decomposing, dynamic combination of multiple ESs, link of multiple bases and decision coordinating. Finally, a summary and some ideas for the future are presented. 相似文献
53.
He XinguiBeijing Institute of System Engineering. P.O. Box - Beijing P.R.China 《系统工程与电子技术(英文版)》1993,(4)
Fuzzy technology is a newly developed discipline based on fuzzy mathematics. In the recent years, it has been successfully applied into many areas, such as process control, diagnosis,evaluation, decision making and scheduling, especially in simulation where accurate mathematical models can not or very hard be established. In this paper, to meet the demands of fuzzy simulation, two fuzzy nets will first be presented, which are quite suitable for modeling the parallel or concurrent systems with fuzzy behavior. Then, a concept of active simulation will be introduced, in which the simulation model not only can show its fuzzy behavior, but also has a certain ability which can actively perform many very useful actions, such as automatic warning, realtime monitoring, simulation re-sult checking, simulation model self-adapting, error recovery, simulating path tracing, system states inspecting and exception handling, by a unified approach while some specified events occur. The simulation model described by this 相似文献
54.
Zhou XianminShanghai Research & Development Centre Guil in Road Shanghai P.R.China 《系统工程与电子技术(英文版)》1993,(4)
Computer simulation models may by used to gain further information about missile performance variability. Model validation is an important aspect of the test program for a missile system. Validation provides a basis for confidence in the model's results and is a necessary step if the model is to be used to draw inference about the behavior of the real missile. This paper is a review of methods useful for validation of computer simulation models of missile systems and provides a new method with high degree of confidence for validation of computer simulation models of missile systems. Some examples of the use of the new method in validating computer simulation models are given. 相似文献
55.
The paper studies some important issues concerning the classification of industrialregions at the county-level by using methods of correlation-principal component analysis and fuzzycluster technique.According to reality it also gives a case study in which the connty-level industrialregional classification is simulated. 相似文献
56.
57.
金属硫化物矿山开发引发的重金属污染已成为当前急需解决的环境问题. 以南京栖霞山铅锌矿采矿巷道壁上的现代钙华为研究对象, 利用电子探针、扫描电子显微镜和X射线粉末衍射分析等矿物学手段, 分析了钙华中的矿物组成及其重金属元素的赋存形态和分布状况. 结果表明钙华的主要矿物成分为方解石. 尽管地层水的重金属含量较低, 但是钙华中碳酸盐矿物的微量元素含量却较高, 最高含量分别为: Mn 23.65%, Zn 9.60%, Mg 0.76%, Fe 4.44%和Pb 0.66%. 钙华在电子探针背散射电子像中呈现出复杂的韵律壳层构造, 成分分析表明这种韵律壳层构造与重金属的分布有关. 另外, 在钙华中见有螺旋状及团絮状物质可能表明微生物参与了钙华的形成过程, 并与重金属的富集存在关联. 所报道的高度富锌-锰方解石对矿山环境中的重金属污染治理具有可借鉴意义. 相似文献
58.
One of the most important issues to resolve in parts manufactured from rapid manufacturing (RM) technologies is to know their behavior working under real conditions. Total quality manufacturing (TQM) is only possible if mechanical properties are well known in the design stage depending on the processing parameters. This work is mainly focused on testing of several samples made with different selective laser sintering (SLS) parameters and technologies. This procedure is the starting point to establish a basis for designing for RM and the standardization of RM testing. The experiments and the analysis of variance (ANOVA) analyzed the effects of several factors on mechanical properties. The SLS technologies were 3DSystem and EOS. The results show which factor has a large effect on the variables and the interaction between them. The conclusions are very useful for developing rules for designing (designing for RM) and creating new standard rules (ISO, AISI, and DIN) for RM materials and parts testing. The ANOVA gives a better knowledge of the effects of these factors and eliminates unimportant parameters. 相似文献
59.
60.
Luís Campos Ribeiro 《Annals of science》2020,77(1):50-70
ABSTRACTThis paper explores the rules for the expurgation of texts of astrology in the Iberian Indices of forbidden books. It addresses the prohibitions put forward in Rule IX of the Index of Trent and the bull Coeli et terrae of Sixtus V, and studies its impact on the rules and their interpretation in the Spanish and Portuguese Indices, in particular, those published in the first decades of the seventeenth century: the Spanish Index librorum prohibitorum et expurgatorum of 1612 and the Portuguese Index auctorum damnatae memoriae of 1624. It shows how these indices offer a more meticulous examination of the prohibitions providing not only more detail regarding the different practices of astrology, but also explicitly accept the doctrine of inclinations of Thomas Aquinas as a central rule to deal with astrological judgments on human behaviour. It also highlights some specific details of the practice of censorship of astrological books by examining case studies of censored Portuguese and Spanish astrological publications. These provide new dimensions and highlight significant differences between the theoretical rules, practical guidelines, and actual restriction of astrological content. 相似文献