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Robust Disturbance Rejection Based Control with Extended-state Resonant Observer for sway Reduction in Uncertain Tower-cranes

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International Journal of Automation and computing 2019年第6期16卷 812-827页

作者： Horacio Coral-Enriquez santiago Pulido-Guerrero john cortés-romero Programa de Ingeniería Mecatrónica Facultad de IngenieríaUniversidad de San Buenaventura sede BogotáCra.8H No 172-20 Edif.DBBogotáOf204Colombia Departamento de Ingeniería Eléctrica y Electrónica Facultad de IngenieríaUniversidad Nacional de Colombia sede BogotáCra.30 No 45-03 Edif.453BogotáOf222Colombia

In this paper, the problem of load transportation and robust mitigation of payload oscillations in uncertain tower-cranes is addressed. This problem is tackled through a control scheme based on the philosophy of active-disturbance-rejection. Here, a general disturbance model built with two dominant components: polynomial and harmonic, is stated. Then, a disturbance observer is formulated through state-vector augmentation of the tower-crane model. Thus, better performance of estimations for system states and disturbances is achieved. The control law is then formulated to actively reject the disturbances but also to accommodate the closed-loop system dynamics even under system uncertainty. The proposed control schema is validated via experimentation using a small-scale tower-crane,and compared with other relevant active disturbance rejection control(ADRC)-based techniques. The experimental results show that the proposed control scheme is robust under parametric uncertainty of the system, and provides improved attenuation of payload oscillations even under system uncertainty.

关键词： Active disturbance rejection control(ADRC) extended state observer(EsO) tower-crane control resonant observer disturbance observer linear matrix inequality

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Tuning of active disturbance rejection control for differentially flat systems under an ultimate boundedness analysis: a unified integer-fractional approach

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Control Theory and Technology 2021年第1期19卷 127-141页

作者： Jeisson E.Otero-Leal john cortes-romero Efredy Delgado Aguilera Felipe Galarza-Jimenez Alexander Jimenez-Triana Departamento de Eléctricay Electrónica Facultad de IngeníeraUniversidad Nacional de ColombiaBogotáD.C..Colombia Department of Control Engineering Universidad Distrital Francisco Joséde CaldasBogotáColombia

An adaptation of the active disturbance rejection control(AD RC)approach is applied to a fractional-order system with a flat *** the rather scarce information about the system,the conditions to establish an ultimate bound for a specific configuration of the system are found and compiled in a guideline for the tuning of the observer implemented in the ADRC.

关键词： ADRC Fractional-order system Ultimate bound Final value theorem

Comparison of lipid extraction methods for the microalgae Acutodesmus obliquus

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International Journal of Agricultural and Biological Engineering 2018年第5期11卷 211-217页

作者： Diana Ximena Hurtado Claudia Lorena Garzón-Castro Jhon cortés-romero Edisson Tello Camacho Bioprospecting and CAPsAB Research Groups Faculty of EngineeringUniversidad de La SabanaCundinamarca 53753Colombia Biosciences Doctoral Program Faculty of EngineeringUniversidad de La SabanaCundinamarca 53753Colombia Department of Electrical and Electronic Engineering Universidad Nacional de ColombiaBogotá53753Colombia

Microalgae are widely used in the pharmaceutical and energy industries,therefore the conditions for their cultivation and extraction methods play an important role in the profiling and acquisition of *** efficiency of lipid extraction from microalgae has attracted great interest from industry because of the wide variety of lipids and amounts that can be *** obliquus(scenedesmus obliquus UTEX 393)was used in this *** was cultivated in Bold 3N medium modified with 75%nitrogen at 25℃,pH 6.8,125 r/min and a photoperiod of 18/6 h and illuminated with white light provided by a Light-Emitting Diode surface Mount Device extensions(LED sMD)with an intensity of 1200μE/(m^(2)·s).The cells were stained with the Red Nile(RN)technique to indicate lipid *** extraction methods were compared,classical,microwave(MW),soxhlet,and ultrasound(Us),using the same solvent proportions(hexane:chloroform:methanol=1:2:3).All samples were analyzed with Fourier Transform Infrared spectroscopy(FTIR)and Gas Chromatography coupled to Mass spectrometry(GC-Ms).The results showed:1)lipid production detected by RN was consistent with microalgal growth;2)the MW technique was the best extraction method,according to the statistical analysis through Randomized Complete Block(RCB)design and performance of 4.6%;and 3)the presence of saturated and unsaturated acids was indicated by FTIR ***-Ms was able to identify palmitic and linoleic acids as the likely major constituents of the sample.

关键词： Acutodesmus obliquus lipid extraction trans-esterification Red Nile(RN)

Fully reversible spectral compression of arbitrary pulsed data signals

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Photonics Research 2020年第5期8卷 659-670页

作者： LUIs romero cortés REZA MARAM JOséAZANA Institut National de la Recherche scientifique–énergie Matériaux et Télécommunications(INRS–EMT)H5A 1K6 MontrealQuebecCanada

Data signals consisting of arbitrarily modulated sequences of pulses are extensively used for processing and communication *** spectral extent of such signals is determined by the bandwidth of the individual pulses in the sequence,which imposes a fundamental limit to the maximum amount of information that can be transmitted or processed per time *** this work,we propose and experimentally demonstrate that the frequency spectrum occupied by a data-modulated pulse sequence can be significantly compressed to well below the individual pulse bandwidth while still maintaining the temporal duration of the pulses in the sequence and without losing any of the information carried by the *** proposed method involves fully reversible linear transformations of the data signal along the time and frequency *** demonstrate successful pulse-shapepreserving spectral compression and subsequent full waveform and information recovery of a^10 Gb/s optical pulse sequence,modulated by an arbitrary data pattern,liberating over 60%of its *** findings should prove useful for applications in signal processing,communications,and others.

关键词： spectral preserving pulsed

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Computational algorithms to simulate the steel continuous casting

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 596-607页

作者： A. Ramírez-López G. soto-cortés M. Palomar-Pardavé M.A. romero-Romo R. Aguilar-López Institute Polytechnic National(Mexico) Department of Materials Metropolitan Autonomous University

Computational simulation is a very powerful tool to analyze industrial processes to reduce operating risks and improve profits from equipment. The present work describes the development of some computational algorithms based on the numerical method to create a simulator for the continuous casting process, which is the most popular method to produce steel products for metallurgical industries. The kinematics of industrial processing was computationally reproduced using subroutines logically programmed. The cast steel by each strand was calculated using an iterative method nested in the main loop. The process was repeated at each time step （？t） to calculate the casting time, simultaneously, the steel billets produced were counted and stored. The subroutines were used for creating a computational representation of a continuous casting plant （CCP） and displaying the simulation of the steel displacement through the CCP. These algorithms have been developed to create a simulator using the programming language C＋＋. Algorithms for computer animation of the continuous casting process were created using a graphical user interface （GUI）. Finally, the simulator functionality was shown and validated by comparing with the industrial information of the steel production of three casters.

关键词： continuous casting simulation numerical method computational algorithm

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Expanding the Boundaries of the Chemical space of DNA Methyltransferase 1 Modulators

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Computational Molecular Bioscience 2024年第1期14卷 1-16页

作者： Massyel s. Martínez-cortés Diana L. Prado-romero José L. Medina-Franco DIFACQUIM Research Group Department of Pharmacy School of Chemistry Universidad Nacional Autónoma de México Avenida Universidad 3000 Mexico City México

DNA methyltransferase 1 (DNMT1), one of the main epigenetic targets, is involved in the duplication of the DNA methylation pattern during replication, and it is essential for proper mammalian development. small molecule DNMT1 modulators are attractive for biochemical epigenetic studies and have the potential to become drugs. so far, more than five hundred small molecules have been reported as DNMT1 inhibitors. However, only a limited number of DNMT1 activators have been disclosed because, at least in part, DNMT1 activators are typically regarded as negative data in virtual screening campaigns or optimization projects. This manuscript aims to report the chemical structures and biological activity of small molecules that increase the enzymatic activity of DNMT1. Results of the biochemical experimental assays are discussed. It was found that small molecule activators have a large variety of chemical scaffolds but share pharmacophore features. Visual analysis of the chemical space and multiverse based on molecular fingertips supported that activators are structurally diverse. This is the first report of eight small molecules that increase the enzymatic activity of DNMT1 by more than 400% in an enzymatic-based assay. The outcome warrants further investigation of the epigenetic activity of the compounds in a counter-screen assay, e.g., cell-based and in vivo context.

关键词： Chemical Multiverse Chemoinformatics Epigenetics Pharmacophore Hypothesis small Molecules

Cellular modelling using P systems and process algebra

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Progress in Natural science:Materials International 2007年第4期17卷 375-383页

作者： Francisco J. romero-Campero Marian Gheorghe Gabriel Ciobanu john M. Auld Mario J. Pérez-Jiménez Research Group on Natural Computing Department of Computer Science and Artificial IntelligenceUniversity of SevilleAvda.Reina Mercedes41012 SevillaSpain Department of Computer science The University of Sheffield Regent CourtPortobello StreetSheffield S1 4DPUK Romanian Academy Institute of Computer ScienceBlvd. Carol I nr. 11700505IasiRomania

In this paper various molecular chemical interactions are modelled under different computational paradigms. P systems andπ-calculus are used to describe intra-cellular reactions like protein-protein interactions and ... 详细信息

关键词： cellular modelling P systems process algebra.

Assessing methods for multiple imputation of systematic missing data in marine fisheries time series with a new validation algorithm

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Aquaculture and Fisheries 2023年第5期8卷 587-599页

作者： Ivan F.Benavides Marlon santacruz Jhoana P.romero-Leiton Carlos Barreto john Josephraj selvaraj Instituto de Estudios del Pacífico Universidad Nacional de ColombiaTumaco CampusKilometro 30-31CajapíVía Nacional Tumaco-PastoTumacoNarino522020Colombia Ingeniería en Produccion Acuícola Universidad de NarinoCra.22#30-63Torre 4 apto.703San Juan de PastoNarino520004Colombia Facultad de ingeniería Universidad CesmagPasto520004Colombia Datambiente 520001Colombia Autoridad Nacional de Pesca y Acuicultura(AUNAP) 520001Colombia

Time series from fisheries often contain multiple missing *** is a severe limitation that prevents using the data for research on population dynamics,stock assessment,forecasting,and,hence,decision-making around marine *** methods have been proposed to impute missing data in univariate time ***,their performances depend not only on the amount of missing data but also on the data *** study compares the performance of twelve imputation methods on the time series of marine fishery landings for six species in the Colombian Pacific *** other studies,we validate the precision of the imputations in the same target time series that include missing data,using the Known sub-sequence Algorithm(KssA),a novelty validation approach that simulates missing data in known sub-sequences of the target time *** results showed that the best methods for imputation are seasonal Decomposition with Kalman filters and structural Models with Kalman filters fitted by maximum *** also show that validating the imputation methods with other time series different to the target time series,leads to wrong imputation methods *** is noteworthy that these methods and also the validation framework are mainly suited to time series with non-random distribution of missing data,this is,missing data produced systematically in chunks or clusters with predictable frequency,which are common in marine sciences.

关键词： Data gaps Fish populations Artisanal fishing Time series imputation

Degradation of Indigo Carmine Using Advanced Oxidation Processes: synergy Effects and Toxicological study

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Journal of Environmental Protection 2016年第12期7卷 1693-1706页

作者： Elba Ortiz Violeta Gómez-Chávez Carlos M. cortés-romero Hugo solís Rubén Ruiz-Ramos sandra Loera-serna Department of Basic sciences Universidad Autónoma Metropolitana Azcapotzalco Mexico City Mexico Faculty of Engineering Universidad Autónoma de Querétaro-Campus Aeropuerto Queretaro Mexico Institute of Forensic Medicine Universidad Veracruzana Veracruz Mexico

The physicochemical degradation of Indigo Carmine (IC) dye in aqueous solution was performed using single and combined Advanced Oxidation Processes (AOP’s). Photocatalysis (TiOsub>2sub>-UV), Ozonation (Osub>3sub>) and sonolysis (sN) were tested either in a standalone methodology or by combination of two simultaneous AOP’s. The dye conversion was followed by both measurements: 1) color removal determined by UV-VIs spectrometry and 2) organic and inorganic load determined by the chemical oxygen demand (COD). A complete and quick color disappearance of model water waste has been obtained by using combination of non-irradiated AOP’s, namely, O3sub>/sN, which contrasts to the combination of irradiated photocatalysis with O3sub> or sonolysis. Color removal with simultaneous TiO2sub>-UV/sN reached 77% while TiO2sub>-UV/O3sub> reached 96% at similar reaction time. On the other hand, the standalone O3sub> yielded the highest color removal (94.4%) in 32 minutes whereas sN reached only 39.2% in 4 hours. The standalone light irradiated TiO2sub>-UV reached 93.3% color re-moval in one hour of reaction time. These results indicated that non-irradiated (sN and O3sub>) enhance synergistic effects that provoke structural changes in dye molecule without reaching total degradation. This is evidenced from FTIR of residuals from reaction mixture in which it has been observed the presence of organic molecules such as aromatics, sulfonic and amines refractory compounds that are mechanisti-cally possible to be found during IC degradation. Also, toxicity tests (MicroToxsup>?sup> Technique) were performed using commercially available bacteria culture before and after IC degradation for each AOP and their combination. Reduction of aqueous dye concentration decreased the level of toxicity of the treated water which is the main target of the AOP’s but the presence of the remaining recalcitrant compounds have also toxic effect.

关键词： Photocatalysis Ozonation sonolysis Indigo Carmine synergy Toxicological