The Brazilian experience with agroecological extension: a critical analysis of reform in a pluralistic extension system     

Vivien Diesel  Marcelo Miná Dias 《The Journal of Agricultural Education and Extension》2016,22(5):415-433

ABSTRACT

Purpose: To analyze the Brazilian experience in designing and implementing a recent extension policy reform based on agroecology, and reflect on its wider theoretical implications for extension reform literature. Design/methodology/approach: Using a critical public analysis we characterize the evolution of Brazilian federal extension policy between 2004 and 2015, using political and legal documents as well as recent academic studies for policy frame characterization and implementation analysis. Findings: The case reveals the difficulty of implementing an agroecological extension approach as part of the endogenous development proposal expressed in 2004 PNATER. The agroecological proposal tended to be impaired by a more general demand for diverse public policy programs implementation, facing a series of institutional constraints. A policy reframing process led to a search for alternatives to make it compatible with a federal centralization trend and public administration rules, resulting in a contracting out emphasis. Theoretical implications: The study shows the political economy aspects of extension reform, and how original plans are influenced by path dependence and different and contrasting demands. Practical implications: The study points to the importance of considering political and institutional environments in extension reforms, and indicates a necessity for additional reflection about strategies for scaling up proposals for agroecological and sustainability oriented extension. Originality/value: Few studies are dedicated to understanding the political economy of extension reform, and reform of Brazilian rural extension systems.  相似文献   

Design of a fast real-time LPV model predictive control system for semi-active suspension control of a full vehicle     

Marcelo Menezes Morato  Manh Quan Nguyen  Olivier Sename  Luc Dugard 《Journal of The Franklin Institute》2019,356(3):1196-1224

This article is concerned with the control of a Semi-Active suspension system of a 7DOF Full Vehicle model, equipped with four Electro Rheological (ER) dampers, taking into account their incipient dissipativity constraints. Herein, a real-time, fast, advanced control structure is presented within the Model Predictive Control framework for Linear Parameter Varying (LPV) systems. The control algorithm is developed to provide a suitable trade-off between comfort and handling performances of the vehicle in a very limited sampling period ($T_s=5\text{ms}$), in view of a possible realtime implementation on a real vehicle. The control structure is tested and compared to other standard fast control approaches. Full nonlinear realistic simulation results illustrate the overall good operation and behaviour of the proposed control approach.  相似文献   

Quality flaw prediction in Spanish Wikipedia: A case of study with verifiability flaws     

Edgardo Ferretti  Leticia Cagnina  Viviana Paiz  Sebastián Delle Donne  Rodrigo Zacagnini  Marcelo Errecalde 《Information processing & management》2018,54(6):1169-1181

In this work, we present the first quality flaw prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove). Based on the underlying characteristics of each flaw, different state-of-the-art approaches were evaluated. For articles not citing any references, a well-established rule-based approach was evaluated and interesting findings show that some of them suffer from Refimprove flaw instead. Likewise, for articles that need additional citations for verification, the well-known PU learning and one-class classification approaches were evaluated. Besides, new methods were compared and a new feature was also proposed to model this latter flaw. The results showed that new methods such as under-bagged decision trees with sum or majority voting rules, biased-SVM, and centroid-based balanced SVM, perform best in comparison with the ones previously published.  相似文献   

Effects of audiovisual stimuli on psychological and psychophysiological responses during exercise in adults with obesity     

Marcelo Bigliassi  João P. A. Greca  Vinícius Barreto-Silva  Priscila Chierotti  Arli R. de Oliveira  Leandro R. Altimari 《Journal of sports sciences》2019,37(5):525-536

The present experiment sought to further understanding of the effects of personalised audiovisual stimuli on psychological and psychophysiological responses during exercise in adults with obesity. Twenty-four participants (M_age = 28.3, SD = 5.5 years; M_BMI = 32.2, SD = 2.4) engaged in self-paced exercises on a recumbent cycle ergometer and three conditions (sensory stimulation [ST], sensory deprivation [DE], and control [CO]) were administered. Perceptual (attentional focus and perceived exertion), affective (affective state and perceived activation), and psychophysiological (heart rate variability) parameters were monitored throughout the exercise bouts. A one-way repeated measures analysis of variance was used to compare self-reported and psychophysiological variables (main and interaction effects [5 Timepoints × 3 Conditions]). The results indicate that ST increased the use of dissociative thoughts throughout the exercise session (η_p² = .19), ameliorated fatigue-related symptoms (η_p² = .15) and elicited more positive affective responses (η_p² = .12) than CO and DE. Accordingly, personally-compiled videos are highly effective in ameliorating exertional responses and enhancing affective valence during self-paced exercise in adults with obesity. Audiovisual stimuli could be used during the most critical periods of the exercise regimen (e.g., first training sessions) when individuals with obesity are more likely to focus on fatigue-related sensations.  相似文献   

Analysis of integrated STATCOM-SMES based on three-phase three-level multi-pulse voltage source inverter for high power utility applications     

Marcelo G. Molina  Pedro E. Mercado 《Journal of The Franklin Institute》2011,348(9):2350-2377

This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller.  相似文献   

The effects of accountability on higher education     

Marcelo Rezende 《Economics of Education Review》2010

This paper analyzes the effects of a higher education accountability system in Brazil. For each discipline, colleges were assigned a grade that depended on the scores of their students on the ENC, an annual mandatory exam. These grades were then disclosed to the public and colleges were rewarded or penalized based on them. I find that the ENC had a positive effect on the education and the proportion of full-time faculty and that it increased the number of vacancies offered, applicants and enrollments. Colleges were affected differently depending on grades, ownership and academic organization, changing the distribution of students among them.  相似文献   

Within,between, above,and beyond: (Pre)positions for a history of the internationalisation of educational practices and knowledge     

Marcelo Caruso 《Paedagogica Historica: International Journal of the History of Education》2014,50(1-2):10-26

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Finding and tracing the effects of governance processes in the New Opportunities Initiative: an outline     

Marcelo Marques 《International Journal of Lifelong Education》2014,33(3):290-308

Based on a Globally Structured Agenda for Education, this article presents the construction of the New Opportunities Initiative in Portugal. Thus, it analyses the relationship between the European Union and the Portuguese State with regard to the construction of this programme, identifying for this purpose the effects of governance processes. Through an analysis of Education and Training 2010 Program and New Opportunities Initiative documents, issued between 2000 and 2010, the strengthening of the discursive rhetoric based on a utilitarian and instrumental perspective of adult education and the incorporation of the principles of new public management in the field of education can be shown. In Portugal, the New Opportunities Initiative not only reflects these trends but also gives rise to a new way of constructing policies in the field of adult education.  相似文献   

More than Bags of Words: Sentiment Analysis with Word Embeddings     

Elena Rudkowsky  Martin Haselmayer  Matthias Wastian  Marcelo Jenny  Štefan Emrich  Michael Sedlmair 《Communication methods and measures》2018,12(2-3):140-157

ABSTRACT

Moving beyond the dominant bag-of-words approach to sentiment analysis we introduce an alternative procedure based on distributed word embeddings. The strength of word embeddings is the ability to capture similarities in word meaning. We use word embeddings as part of a supervised machine learning procedure which estimates levels of negativity in parliamentary speeches. The procedure’s accuracy is evaluated with crowdcoded training sentences; its external validity through a study of patterns of negativity in Austrian parliamentary speeches. The results show the potential of the word embeddings approach for sentiment analysis in the social sciences.  相似文献