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111.
Hiram Ponce Mario Acevedo Noel Esparza-Duran 《Journal of The Franklin Institute》2019,356(16):9432-9450
Intelligent control systems are able to work well in uncertain nonlinear systems, mainly for: changes in the operating point, presence of environmental noise and disturbances, uncertainty in sensor measurements, miscalibration, uncertain model plant, and others. For instance, fuzzy controllers have been widely studied and applied. Recently, artificial organic controllers (AOC) have been proposed as an ensemble of fuzzy logic and artificial hydrocarbon networks. However, a weakness in AOC is the lack of training methods for tuning parameters for desired output responses in control. In this regard, this paper aims to introduce an evolutionary optimization method, i.e. particle swarm optimization, for tuning artificial organic controllers. Three objectives are proposed for automatic tuning of AOC: overall error, steady-state error and settling time of output response. The proposed methodology is implemented in the well-known cart-pole system. Also, the proposed method is applied on a one-leg unstable mechanism as case study. Results validate that automatic tuning of AOC over simulation systems can achieve suitable output responses with minimal overall error, steady-state error and settling time. 相似文献
112.
This paper presents a North-South technology gap model which combines the Schumpeterian approach to technical and structural change with the Keynesian perspective on effective demand and the Balance-of-Payments (BOP) constraint as drivers of growth. Three are the contributions of the paper. First, it develops a model in which the technology gap, relative productivity and relative wages co-evolve and may generate different paths of convergence or divergence between South and North depending on the parameters of the model. Second, the parameters of the model are associated with different types of policies, which allows for discussing how these policies may change the growth path. Finally, the model is used to discuss the contrasting experiences of Asia and Latin America since 1970. Convergence in Asia and divergence in Latin America have been extensively debated topics in the literature on comparative economic development, which highlights the crucial role of industrial policy. It is argued that the results of the technology gap model are consistent with the findings of this literature and helps understand the forces behind convergence and divergence. 相似文献
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Mario MONZóN 《浙江大学学报(A卷英文版)》2018,19(4):329-330
正Osteoarthritis(OA)is a degenerative joint disease,typified by a loss of quality of cartilage and changes in bone at the interface of a joint,resulting in pain,stiffness,and reduced mobility."According to the World Health Organization,40%of people over the age of 70 have OA.This joint disease affects 相似文献
114.
We investigate whether having an advisor of the same gender is correlated with the productivity of PhD science students and their propensity to stay in academic science. Our analysis is based an original dataset – combined from dissertation abstracts, faculty directories and bibliometric data – covering nearly 20,000 PhD graduates and their advisors from U.S. chemistry departments. We find that students working with advisors of the same gender tend to be more productive during the PhD; and that female students working with female advisors are considerably more likely to become faculty themselves. We suggest that the under-representation of women in science and engineering faculty positions may perpetuate itself through the lower availability of same-gender advisors for female students. 相似文献
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Mario Reguzzoni 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1974,20(1):53-62
Ohne Zusammenfassung
Educational reform in the european community
Reforme En Education Dans La Communaute Europeenne相似文献
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The period of Portuguese authoritarian government, followingupon the heels of economic and social decline which the countrylived through after the installation of the republic in 1910,was bolstered politically, culturally, and economically by theexperience of the country during these 64 years. Economic andcultural changes after 1945, including development of the media,worker migrations, tourism, and the decolonialization movements,gave rise to attitudes and behavior of increasingly wide groupswho rejected authoritarianism and the monolithic political system.Various factors paved the way for the downfall of this regime,among them Oliveira Salazar's physical incapacity and his replacementby the more liberal but less prestigious Marcelo Caetano, theunease in public opinion caused by the sending of troops tothe colonies in Africa, and international and political andcultural pressures. Public opinion was in favor of the new politicalsystem, and, gradually consolidated its hold with the supportof the Western international community, and, in particular,the countries of the EEC. The political parties contributedto the development of the political attitudes of the Portuguesepopulation and ensured that the regime maintained itself withina liberal democratic framework. 相似文献