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Fuzzy C-means Rule Generation for Fuzzy Entry Temperature Prediction in a Hot Strip Mill

Journal of Iron and Steel Research International 2016年第2期23卷 116-123页

作者： Jose Angel BARRIOS Cesar VILLANUEVA Alberto CAVAZOS rafael colas Mechanical and Electrical Engineering Faculty Autonomous University of Nuevo LeonSan Nicolas de los Garza 66451Nuevo LeonMexico Hot Rolling Department Ternium ChurubuscoMonterrey 64000Nuevo LeonMexico

Variable estimation for finishing mill set-up in hot rolling is greatly affected by measurement uncertainties, variations in the incoming bar conditions and product changes. The fuzzy C-means algorithm was evaluated for rule base generation for fuzzy and fuzzy grey-box temperature estimation. Experimental data were collected from a real- life mill and three different sets were randomly drawn. The first set was used for rule-generation, the second set was used for training those systems with learning capabilities, while the third one was used for validation. The perform- ance of the developed systems was evaluated by five performance measures applied over the prediction error with the validation set and was compared with that of the empirical rule-base fuzzy systems and the physical model used in plant. The results show that the fuzzy C-means generated rule-bases improve temperature estimation; however, the best results are obtained when fuzzy C-means algorithm, grey-box modeling and learning functions are combined. Application of fuzzy C-means rule generation brings improvement on performance of up to 72%.

关键词： gray-box modeling ANFIS hot rolling temperature estimation fuzzy C-means rule base generation

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Conifer establishment after the eruption of the Paricutin volcano in central Mexico

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Forest Ecosystems 2022年第1期9卷 71-82页

作者： Jesús Eduardo Sáenz-Ceja Blanca Lizeth Sáenz-Ceja J.Trinidad Sáenz-Reyes Diego rafael Pérez-Salicrup Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autéonoma de MéxicoAntigua Carretera a Patzcuaro 8701 Col.Ex hacienda San Joséde la Huerta58190MoreliaMexico Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de MéxicoAntigua Carretera a Patzcuaro 8701 Col.Ex hacienda San Joséde la Huerta58190MoreliaMexico Instituto Nacional de Investigaciones Forestales Agrícolas y PecuariasCampo Experimental UruapanAv.Latinoamericana 1101Col.Revolución60500UruapanMexico

Background:Volcanic eruptions have large effects on forest ecosystems and create new substrates,triggering primary succession *** Paricutín volcano,born in central-western Mexico,erupted between 1943 and *** the cessation of the eruptive activity,plant colonization began on the lava flows and tephra deposits,including the conifer species that dominate the surrounding mature *** study aims to reconstruct the history of the establishment of conifer trees on the substrates created by the Paricutín ***:16 sampling plots were established along three transects with northern,southern,and south-western aspects,located every 250 m from the preserved forest to the volcanic *** cores from 400 conifer trees were extracted and their age was determined by cross-dating annual tree *** order of the species colonization and the tree establishment,abundance,and dominance patterns were ***,the influence of the distance from the mature forests and the inter-annual climatic conditions on the temporal tree establishment pattern was ***:Eight pine and one fir species have been established since 1970,only 18 years after the end of the eruptive ***,tree establishment increased by 12.9%annually after 1995,with the youngest tree in our sample getting established in *** did not find a well-defined temporal and spatial pattern of species arrival,which suggests that colonization occurred randomly,although the four pine species that were established early became the most abundant and *** establishment was not influenced by the distance from the mature forest,and wet inter-annual conditions did not enhance pulses of tree recruitment,exhibiting a continuous tree establishment ***:Conifer species have shown a great capacity for colonizing volcanic substrates created by the Paricutín eruption,which suggests that tropical montane conifers can regenerate rapidly under high-magni

关键词： Age structure Dendrochronology Lava flow Primary succession Tropical montane forest

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Land cover changes and fragmentation in mountain neotropical ecosystems of Oaxaca, Mexico under community forest management

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Journal of Forestry Research 2019年第1期30卷 143-155页

作者： rafael M~a Navarro Cerrillo Dennis J.Esteves Vieira Susana Ochoa-Gaona Bernardus H.J.de Jong M~a del Mar Delgado Serrano Depto. Ingeniería Forestal Laboratorio de SelviculturaDendrocronología y Cambio Climático.Dendrodat Lab-ERSAF Universidad de Córdoba Depto. de Engenharia Florestal Faculdade de Engenharia Florestal Laboratório de Sensoriamento Remoto e Geotecnologia Universidade Federal de Mato Grosso Departamento de Ciencias de la Sustentabilidad El Colegio de la Frontera Sur-Unidad Campeche Depto. Economía Sociología y Política Agrarias Grupo de Evaluación y Restauración de Sistemas Agrícolas y Forestales-ERSAF Universidad de Córdoba

Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat images and OBIA methodology. Additionally, landscape analyses using FRAGSTAT were conducted. In 2014, Sierra de Juarez–Oaxaca was covered by approximately 84% of forests, mainly pine-oak and cloud forests. After extensive deforestation until 2001, this trend was reversed and the forest cover surface area in 2014 was slightly higher than in 1979. The comparison of the landscape structure of the forested and agricultural lands suggests an increase in habitat heterogeneity. However, interspersion and juxtaposition indices, showing the patch shape by patch area and perimeter, were similar throughout the study period(1979–2014). Social and economic drivers can explain this situation: namely, community organization, forest enterprises, payment for ecosystem services programs, and changes of agricultural activity. Communities in the Sierra of Oaxaca have reforested degraded lands, created community forest enterprises, and preserved the forest under conservation schemes like those proposed by the Mexican payment for ecosystem services programs. However, their sustainable management faces internal challenges and has become highly dependent on political and institutional decisions beyond their control.

关键词： Tropical and temperate forests Social forestry Land uses segmentation OBIA FRAGSTAT

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