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Robust flat filtering DSP based control of the boost converter

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Control Theory and Technology 2016年第3期14卷 224-236页

作者： Hebertt SIRA-ramirez Arturo HERNANDEZ-mendez Jesus LINARES-FLORES Alberto LUVIANO-JUAREZ Department of Hectrical Engineering Mechatronics Section ClNVESTAV-IPN Av. IPN No. 2508 Col. San Pedro Zacatenco 07360 D.F. Mexico Mexico Universidad Tecnologica de la Mixteca Carretera a Acatlima Kin. 2.5 Huajuapan de Leon Oaxaca Mexico UPIITA-IPN D.F. Mexico Mexico

The article deals with the design and implementation of a flat filter tracking digital controller for a boost DC-DC power converter. A highly perturbed switched boost converter circuit is shown to be efficiently controlled, in a trajectory tracking task for its non-minimum phase output, by means of a suitable linear filter, here addressed as a flat filter. Flat filtering is a natural robust version of generalized proportional integral control （GPIC） by which the effects of arbitrary time varying exogenous disturbances, unknown endogenous nonlinearities and un-modeled dynamics can be jointly attenuated in a conceptually similar fashion to observer-based active disturbance rejection control （ADRC） and algebraic identification based model free control （MFC） but： a） without using extended state observers and b） respecting the original system order in a time-varying simplified model while avoiding algebraic estimation techniques. The proposed control technique based on the TMS320F28335 digital signal processor chip is tested by means of realistic simulations and experimental setup.

关键词： Flat filter DSP-implementation boost converter

Experimental determination and modeling of equilibrium moisture content from the sapwood of Mexican pine (Pinus pseudostrobus Lindl.)

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Forestry Studies in China 2011年第4期13卷 285-289页

作者： Juan RODRIGUEZ-ramirez Sadoth SANDOVAL-TORRES Lilia mendez-LAGUNAS Artemio Carrillo PARRA Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional (CIIDIR) Oaxaca Instituto Politécnico Nacional Oaxaca 71230 Mexico Facultad de Ciencias Forestales Universidad Autónoma de Nuevo León Linares Nuevo León 67700 Mexico

A desorption isotherm is a very important basis in the understanding of drying process. In this study, the desorption isotherms from the sapwood of Mexican pine （Pinus pseudostrobus Lindl.） were determined by the gravimetric method （discontinuous control of sample weight） at 30℃ and 50℃. The salt method was used in the range of water activities from 0.11 to 0.89. The results show that the desorption ability of Mexican pine sapwood increased with temperature at a given relative humidity. The experimental data was further simulated with the models, i.e., BET, GAB, Oswin and Henderson models. The GAB, Oswin and Henderson models allow the representation of the entire desorption isotherms. The BET model showed a better fit for water activity lower than 0.35, with a mean relative deviation of 0.0286 at 30℃ and 0.0167 at 50℃. Simultaneously, the BET model gave a better representation of moisture content in the monolayer saturation region. Overall, the GAB model ensured the best simulation of the entire isotherm, while the Henderson model displayed the worst simulation.

关键词： modeling isotherms Mexican pine sapwood

A System Identification-based Modeling Framework of Bidirectional DC-DC Converters for Power Grids

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Journal of Modern Power Systems and Clean Energy 2022年第3期10卷 788-799页

作者： Gabriel E.Mejia-Ruiz Mario R.A.Paternina Juan R.Rodriguez R. Juan M.ramirez Alejandro Zamora-mendez Guillermo Bolivar-O. Department of Electrical Engineering National Autonomous University of Mexico(UNAM)Mexico CityMexico Department of Electrical Engineering Center for Research and Advanced Studies(CINVESTAV)GuadalajaraMexico Electrical Engineering Faculty Michoacan University of Saint Nicholas of Hidalgo(UMSNH)MoreliaMexico Engineering Faculty Corporacion Universitaria Minuto de Dios-UNIMINUTOBelloColombia

This paper proposes a system identification framework based on eigensystem realization to accurately model power electronic *** proposed framework affords an energy-based optimal reduction method to precisely identify the dynamics of power electronic converters from simulated or actual raw data measured at the converter’s *** method does not require any prior knowledge of the topology or internal parameters of the converter to derive the system modal *** accuracy and feasibility of the proposed method are exhaustively evaluated via simulations and practical tests on a software-simulated and hardware-implemented dual active bridge(DAB)converter under steady-state and transient *** various comparisons with the Fourier series-based generalized average model,switching model,and experimental measurements,the proposed method attains a root mean square error(RMSE)of less than 1%with respect to the actual raw ***,the computational effort is reduced to 1/8.6 of the Fourier series-based model.

关键词： Dual active bridge eigensystem realization algorithm generalized average model power electronic converter identification

From flatness, GPI observers, GPI control and flat filters to observer-based ADRC

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Control Theory and Technology 2018年第4期16卷 249-260页

作者： Hebertt SIRA-ramirez CINVESTAV-IPN Department of Electrical Engineering Mechatronics Section Avenida IPN No. 2508 Col. San Pedro Zacatenco CP 07360 CDMX Mexico

In this article, we establish the route taken by the author, and his research group, to bring differential flatness to the realm of active disturbance rejection control （ADRC）. This avenue entitled： 1） generalized proportional integral observers （GPIO）, as natural state and disturbance observers for fiat systems, 2） generalized proportional integral （GPI） control, provided with extra integrations, to produce a modular controller known as flat filters （FF＇s） and, finally, 3） the establishing of an equivalence of observer based ADRC with FF＇s. The context is that of pure integration systems. The obtained controllers depend only on the order of the flat system and they are to be directly used on the basis of the available flat output signal in a universal, modular, fashion. The map is complemented with the relevant references where the intermediate techniques were illustrated and developed, over the years, in connection with laboratory experimental implementations.

关键词： Flatness GPI observers GPI control reduced order GPI observers fiat filters

Air Pollution, Government Pollution Regulation, and Industrial Production in China

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Journal of Systems Science & Complexity 2020年第4期33卷 1064-1079页

作者： CAO Dong ramirez Carlos D. School of Economics and Management Xidian UniversityXi’an 710071China Department of Economics George Mason UniversityFairfaxVAUnited States

Over the last four decades,a severe deterioration in air quality has accompanied China’s rapid *** a result,the Chinese government has implemented stricter policies and regulation to control air *** this paper,the authors create a measure of government policies on air pollution by tracking all pollution-related government announcements in Chinese *** authors then use this variable,along with measures of actual pollution,to investigate how air pollution,industrial production,and government policies on air pollution are *** authors conduct this investigation nationwide,as well as in five large cities in China.A vector autoregression model suggests that,nationwide,government policies seem to decrease air pollution without significantly affecting industrial ***,the effect appears to be short-lived,dissipating after a few *** addition,the authors find that the dynamic relationship among these variables differs by *** instance,following an adverse air quality shock in Beijing,government efforts to control pollution seem to have an ameliorating city-wide effect,decreasing local air pollution in subsequent *** Shanghai and Guangzhou,while the local government reacts to adverse air pollution shocks,the ameliorating effects are not statistically *** Chengdu and Shenyang,the authors detect no significant local government reaction to adverse air pollution ***,in these cities,local government policies do not impart a statistically measurable effect on air pollution.

关键词： pollution. pollution nationwide

Synthesis identification analysis for closed loop system

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Journal of Systems Engineering and Electronics 2021年第4期32卷 939-946页

作者： WANG Jianhong RICARDO A.ramirez-Mendoza School of Electronic Engineering and Automation Jiangxi University of Science and TechnologyGanzhou 343100China School of Engineering and Sciences Tecnologico de MonterreyMonterrey 64849Mexico

The existing theories for closed loop identification with the linear feedback controller are very *** apply the existed theories directly in the control field,we propose a new idea about replacing the original unknown and nonlinear feedback controller with one approximated linear controller,while guaranteeing the equivalent property for the obtained closed loop *** on some statistical correlation functions,one condition is derived to show the equivalent property between the approximated linear controller and the original nonlinear *** detailed explicit form,corresponding to the approximated linear controller,is also ***,to give a complete analysis for closed loop identification,the cost function is rewritten as one extended expression,being convenient to *** spectral estimation is introduced to identify the unknown plant in the closed loop ***,the proposed theories are verified by one simulation example.

关键词： synthesis analysis closed loop system simplified function equivalent controller

Current status and trends of carbon-based electrodes for fully solution-processed perovskite solar cells

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Journal of Energy Chemistry 2022年第5期31卷 222-246页

作者： Laura MGonzález Daniel ramirez Franklin Jaramillo Centro de Investigación Innovacióny Desarrollo de MaterialesCIDEMATFacultad de IngenieríaUniversidad de Antioquia UdeACalle 70 No.52-21Medellín 050010Colombia

Perovskite solar cells(PSCs) have revolutionized photovoltaic research. As a result, a certified power conversion efficiency(PCE) of 25.5% was recorded in late 2020. Although this efficiency is comparable with silicon solar cells;some issues remain partially unsolved, such as lead toxicity, instability of perovskite materials under continuous illumination, moisture and oxygen, and degradation of the metallic counter electrodes. As an alternative to tackle this last concern, carbon materials have been recently used, due to their good electrical and thermal conductivity, and chemical stability, which makes them one of the most promising materials to replace metallic counter electrodes in the fabrication of PSCs. This review highlights the recent advances of carbon-based PSCs, where the carbon electrode(CE) is the main *** have become very promising candidates for PSCs;they are mainly fabricated using a simple combination of graphite and carbon black powders embedded in a binder matrix, giving a paste that is then solution-processable, resulting in devices with improved quality stability, when compared to metallic electrodes. In this review, CE’s composition is emphasized, since it can give both, high and lowtemperature processed electrodes, compatible with different device configurations. Finally, the tendencies and opportunities to use CE in PSCs devices are presented.

关键词： Perovskite solar cells Carbon electrodes Scaling up Stability Solution processing

Improved frost forecast using machine learning methods

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Artificial Intelligence in Geosciences 2023年第1期4卷 164-181页

作者： Jos´e Roberto Rozante Enver ramirez Diego ramirez Gabriela Rozante Center for Weather Forecast and Climate Studies National Institute for Space ResearchCachoeira PaulistaSPBrazil University of Sao Paulo(EEL/USP) LorenaSPBrazil Sao Paulo State University(UNESP) BauruSPBrazil

Frosts are one of the atmospheric phenomena with one of the larger negative effects on the agricultural sector in the southern region of Brazil,therefore,an earlier forecast can minimize their *** the present work,artificial neural networks(ANNs)techniques were applied in order to improve the predicting capabilities of frost events in southern *** the study,two multilayer perceptron(MLP)ANNs were built,one with ADAM optimizer and the other with *** input parameters MLP-ANNs were numerical predictions of the Eta *** ANNs were trained using four years(2012-2015),while validation and testing were performed using 2016 and 2017,*** episode of frost that occurred on May 21st,2018,related to an intense cold air mass,was also utilized to evaluate the performance of the *** best configurations(topologies and hyperparameters)of the ANNs were identified through experiments,using the highest accuracy obtained during the validation period as a *** results of the ANNs with ADAM and SGD optimizers were compared with the predictions of the Eta *** the case study,an additional comparison against the operational frost index(IG)from the National Institute for Space Research(INPE)was also *** performance of both ANNs(properly configured)with ADAM and SGD optimizers are comparable one to the *** both are significantly better compared to the Eta *** ANNs were able to drastically reduce the underestimation trends of frost events caused by the warm bias of the Eta *** ANNs also indicated more satisfactory performances when compared to the INPE *** general,the ANNs were able to identify deficiencies in Eta predictions,and consequently improve their *** this sense,the use of ANNs to predict frost events can be a very useful tool in an operational environment.

关键词： Frost Artificial neural networks Multilayer perceptron frost index Deep learning

Landscape genetics reveals inbreeding and genetic bottlenecks in the extremely rare short-globose cacti Mammillaria pectinifera (Cactaceae) as a result of habitat fragmentation

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Plant Diversity 2017年第1期39卷 13-19页

作者： Reyna Maya-Garcia Santiago Arizaga Pablo Cuevas-Reyes Juan Manuel Penaloza-ramirez Victor Rocha ramirez Ken Oyama Facultad de Biologia Universidad Michoacana de San Nicolas de Hidalgo Mexico Escuela Nacional-de Estudios Superiores Unidad Morelia UNAM Antigua Carretera a Pdtzcuaro 8701 Colonia Ex-Hacienda de SanJose de la Huerta58190 Morelia Michoacan Mexico

Mammillaria pectinifera is an endemic, short-globose cactus species, included in the IUCN list as a threatened species with only 18 remaining populations in the Tehuacfin-Cuicatlan Valley in central Mexico. We evaluated the population genetic diversity and structure, connectivity, recent bottlenecks and population size, using nuclear microsatellites. M. pectinifera showed high genetic diversity but some evidence of heterozygote deficiency （F15）, recent bottlenecks in some populations and reductions in population size. Also, we found low population genetic differentiation and high values of connectivity for M. pectinifera, as the result of historical events of gene flow through pollen and seed dispersal. M. pectinifera occurs in sites with some degree of disturbance leading to the isolation of its populations and decreasing the levels of gene flow among them. Excessive deforestation also changes the original vegetation damaging the natural habitats. This species will become extinct if it is not properly preserved. Furthermore, this species has some ecological features that make them more vulnerable to disturbance such as a very low growth rates and long life cycles. We suggest in situ conservation to prevent the decrease of population sizes and loss of genetic diversity in the natural protected areas such as the Tehuacan-Cuicatlan Biosphere Reserve. In addition, a long-term ex situ conservation program is need to construct seed banks, and optimize seed germination and plant establishment protocols that restore disturbed habitats. Furthermore, creating a supply of living plants for trade is critical to avoid further extraction of plants from nature.

关键词： MammiUaria pectiniferaNuclear SSRGenetic diversityRecent bottlenecksEffective population size