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Design and Robust Performance Evaluation of a Fractional Order PID Controller Applied to a DC Motor

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IEEE/CAA j.urnal of Automatica Sinica 2017年第2期4卷 304-314页

作者： j.Viola L.angel j.M.Sebastian Universidad Pontificia Bolivariana Universidad Politecnica de Madrid Centre for Automation and Robotics (CAR) UPM-CSIC

This paper proposes a methodology for the quantitative robustness evaluation of PID controllers employed in a DC motor. The robustness analysis is performed employing a 2~3 factorial experimental design for a fractional order proportional integral and derivative controller(FOPID), integer order proportional integral and derivative controller(IOPID)and the Skogestad internal model control controller(SIMC). The factors assumed in experiment are the presence of random noise,external disturbances in the system input and variable load. As output variables, the experimental design employs the system step response and the controller action. Practical implementation of FOPID and IOPID controllers uses the MATLAB stateflow toolbox and a NI data acquisition system. Results of the robustness analysis show that the FOPID controller has a better performance and robust stability against the experiment factors.

关键词： Factorial experimental design fractional-order PID controller robustness analysis SIMC PID controller

Software Proj.ct Effort Estimation Based on Multiple Parametric Models Generated Through Data Clustering

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j.urnal of Computer Science & Technology 2007年第3期22卷 371-378页

作者： j.an j.Cuadrado Gallego Daniel Rodríguez Miguel angel Sicilia Miguel Garre Rubio angel García Crespo Department of Computer Science The University of Alcalá AlcaláSpain Department of Computer Science Carlos Ⅲ University.Madrid Spain

Parametric software effort estimation models usually consists of only a single mathematical relationship. With the advent of software repositories containing data from heterogeneous proj.cts, these types of models suffer from poor adj.stment and predictive accuracy. One possible way to alleviate this problem is the use of a set of mathematical equations obtained through dividing of the historical proj.ct datasets according to different parameters into subdatasets called partitions. In turn, partitions are divided into clusters that serve as a tool for more accurate models. In this paper, we describe the process, tool and results of such approach through a case study using a publicly available repository, ISBSG. Results suggest the adequacy of the technique as an extension of existing single-expression models without making the estimation process much more complex that uses a single estimation model. A tool to support the process is also presented. Keywords software engineering, software measurement, effort estimation, clustering

关键词： software engineering software measurement effort estimation clustering

Optimal control of natural resources in mining industry

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International j.urnal of Mining Science and Technology 2015年第2期25卷 193-198页

作者： Petrov Nikolay Tanev angel Electrical Engineering Electronics and AutomationTechnical University-Sofia Faculty of Mathematics and Informatics Sofia University

The paper focuses on the optimal control of natural resources in mining industry. The purpose is to pro- pose an optimal extraction series of these resources during the lifetime of the Mine＇s maintenance. Fol- lowing the proposed optimal control model, a sensitivity analysis has been performed that includes the interest rate impact on the optimal solution. This study shows that the increasing of the interest rate sti- mulates faster extraction of the resources. The discounting factor induces that the resource has to be extracted faster hut this effect is counterbalanced by the diminishing returns of the annual cash flow. At higher parameters of ＂alpha＂ close to one of the power function about 80% from the whole resource will be extracted during the first 4 years of obj.ct/mine maintenance. An existence of unique positive root with respect to return of investment has been proposed and proved by two ways： by the ＂method of chords＂ and by using specialized software.

关键词： Optimal control Natural resources Interest rate Sensitivity analysis Method of chords

炼钢渣和炭的混合物用于微波辅助甲烷干气重整反应(英文)

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催化学报 2012年第7期33卷 1115-1118页

作者： j.se M. BERMUDEZ Beatriz FIDALGO Ana ARENILLAS j. angel MENENDEZ Instituto Nacional del Carbón CSIC Apartado 73 Oviedo 33080 Spain

The use of steel-making slag as catalysts for microwave-assisted dry reforming of CH4 was studied. Two carbon materials (an activated carbon and a metallurgical coke), mixtures of the carbon materials and Fe-rich slag, and mixtures of the carbon materials and Ni/Al2O3 were tested as catalysts. The mixtures of slag with carbons gave rise to higher and steadier conversions than those achieved over the carbon materials alone. In addition, the use of the metallurgical coke mixed with metal-rich catalysts gave rise to remarkable results. Thus, no CH4 and CO2 conversions were achieved when coke was used alone, whereas high conversions were obtained when it was mixed with the metal-rich catalysts.

关键词： steel-making slag carbon catalyst dry reforming microwave heating

Guest Editorial: Power Systems with Increasing Renewable Penetration: Market, Operations, Planning and Regulation

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j.urnal of Modern Power Systems and Clean Energy 2021年第4期9卷 I0001-I0002页

作者： Antonio j.Conej. j.anhui Wang angel Arcos Vargas Ohio State University ColumbusOhioUSA Southern Methodist University DallasTexasUSA University of Seville SevilleSpain

Our goal in putting together this special section is to contribute to the conversation on control,operations,planning and regulation of power systems with increasing renewable *** a conversation will hopefully involve regulators,operators,producers,consumers,and the research *** hope that this special section will spur innovative ideas that will contribute to ensuring a secure,efficient,and environmentally friendly supply of electrical ener-gy,and to eventually achieve a carbon-free electricity *** special section includes 15 research articles on control,operations,regulation,planning,forecasting,and estimation of power systems with increasing renewable penetration.

关键词： Market operations eventually

First-principle calculations of magnetic properties of Ho_(6)(Fe,Mn)Bi_(2)compounds

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Rare Metals 2024年第11期43卷 6034-6047页

作者： angel j.Garcia-Adeva Estibaliz Apinaniz Aritz Herrero Ivan R.Aseguinolaza Alberto Oleaga Departamento de Fisica Aplicada Escuela de Ingenieria de V itoria-GasteizUniversidad del Pais V asco UPV/EHU01006 V itoria-GasteizSpain Departamento de Fisica Aplicada Escuela de Ingenieria de BilbaoUniversidad del Pais V asco UPV/EHU48013 BilbaoSpain

The magnetic properties of Ho_(6)MnBi_(2)and Ho_(6)FeBi_(2)crystals are investigated by means of density functional *** materials are currently an active subj.ct of research in the context of magnetic refrigeration applications since they exhibit a remarkable magnetocaloric *** this work,the equation of state,density of states and magnetic moments are calculated and compared with previous experimental results for these ***,the Curie temperatures for the paramagnetic to ferromagnetic phase transition observed in these systems are calculated from first *** the calculated quantities are in reasonable agreement with experimental data,which suggests that density functional theory could provide a reliable framework to theoretically investigate the magnetic properties of intermetallic ternary compounds.

关键词： Intermetallic compounds Rare earths Magnetic properties Magnetocaloric effect Density functional theory Heisenberg model

Oryza CLIMtools:A genome–environment association resource reveals adaptive roles for heterotrimeric G proteins in the regulation of rice agronomic traits

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Plant Communications 2024年第4期5卷 145-165页

作者： angel Ferrero-Serrano David Chakravorty Kobie j.Kirven Sarah M.Assmann Biology Department Pennsylvania State University208 Mueller LaboratoryUniversity ParkPA 16802USA Intercollege Graduate Degree Program in Bioinformatics and Genomics Pennsylvania State University208 Mueller LaboratoryUniversity ParkPA 16802USA

Modern crop varieties display a degree of mismatch between their current distributions and the suitability of the local climate for their *** address this issue,we present Oryza CLIMtools(https://***/CLIMtools/oryza_v1.0/),thefirst resource for pan-genome prediction of climate-associated genetic variants in a crop *** CLIMtools consists of interactive web-based databases that enable the user to(1)explore the local environments of traditional rice varieties(landraces)in South-East Asia and(2)investigate the environment by genome associations for 658 Indica and 283 j.ponica rice landrace accessions collected from georeferenced local environments and included in the 3K Rice Ge-nomes *** demonstrate the value of these resources by identifying an interplay betweenflowering time and temperature in the local environment that is facilitated by adaptive natural variation in OsHD2 and disrupted by a natural variant in *** quantitative trait locus analysis has suggested the impor-tance of heterotrimeric G proteins in the control of agronomic ***,we analyzed the climate associations of natural variants in the different heterotrimeric G protein *** identified a coordi-nated role of G proteins in adaptation to the prevailing potential evapotranspiration gradient and revealed their regulation of key agronomic traits,including plant height and seed and panicle *** conclude by highlighting the prospect of targeting heterotrimeric G proteins to produce climate-resilient crops.

关键词： Oryza sativa rice G by E adaptation flowering time GWAS OsHD2 OsSOC1 heterotrimeric G pro-tein OsRGA1 d1 OsGS3 OsDEP1 OsGGC2

Arboviruses emerging in Peru: Need for early detection of febrile syndrome during El Ni?o episodes

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Asian Pacific j.urnal of Tropical Medicine 2016年第8期9卷 796-797页

作者： Derek Tantaléan-Yépez j.sé Sánchez-Carbonel Gabriela Ulloa-Urizar Diego Espinoza- morales Miguel angel Aguilar-Luis Wilmer Silva-Caso María j.Pons j.ana del Valle- Mendoza School of Medicine Health Sciences Faculty Universidad Peruana de Ciencias Aplicadas (UPC) Research Center and Innovation of the Health Sciences Faculty Universidad Peruana de Ciencias Aplicadas (UPC)

The presence of El Ni?o Southern Oscillation(ENSO)implies the presence of fluctuating rains in coastal areas and these changes influence the occurrence of febrile syndromes *** Peru,Aedes aegypti is the vector responsible for various viruses such as the dengue,Zika,chikungunya,which is distributed in 18 Peruvian *** viruses cause similar clinical characteristics in the host and for this reason rapid,sensitive and specific diagnostic tests are needed so that the patient can receive timely treatment.

关键词： Febrile syndrome Dengue Chikungunya Zika

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

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

作者： j.se 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