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Evaluate More General Integrals Involving Universal Associated Legendre Polynomials via Taylor's Theorem

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Communications in Theoretical Physics 2017年第8期67卷 177-180页

作者： G.Yaez-Navarro 孙国华孙东升陈昌远董世海 ESFM Instituto Politécnico Nacional Edificio 9 Unidad Profesional ALM Catedrtica CONACyT CIC Instituto Politécnico NacionalUPALM New Energy and Electronic Engineering Yancheng Teachers University Laboratorio de Información Cuntica CIDETEC Instituto Politécnico Nacional Unidad Profesional ALM

A few important integrals involving the product of two universal associated Legendre polynomials P_(l′)^(m′)(x),P_k^n′~′(x)and x^(2a)(1-x^2)^(-p-1),x^b(1±x)^(-p-1)and x^c(1-x^2)^(-p-1)(1±x)are evaluated using the operator form of Taylor’s theorem and an integral over a single universal associated Legendre polynomial.These integrals are more general since the quantum numbers are unequal,i.e.l~′≠k~′and m~′≠n~′.Their selection rules are also given.We also verify the correctness of those integral formulas numerically.

关键词：数值积分公式勒让德多项式泰勒定理估计选择规则量子数伴随

Exponential Continuous Non-Parametric Neural Identifier With Predefined Convergence Velocity

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IEEE/CAA Journal of Automatica Sinica 2022年第6期9卷 1049-1060页

作者： Mariana Ballesteros Rita Q.Fuentes-Aguilar Isaac Chairez Instituto Politécnico Nacional Centro de Innovación y Desarrollo Tecnológico en Cómputo Unidad Profesional Interdisciplinaria de Biotecnología 07340Mexico CityMexico Tecnológico de Monterrey School of Engineering and SciencesZapopanJalisco 45138Mexico Department of Bioprocesses UPIBIInstituto Politécnico Nacional07340Mexico City

This paper addresses the design of an exponential function-based learning law for artificial neural networks(ANNs)with continuous dynamics.The ANN structure is used to obtain a non-parametric model of systems with uncertainties,which are described by a set of nonlinear ordinary differential equations.Two novel adaptive algorithms with predefined exponential convergence rate adjust the weights of the ANN.The first algorithm includes an adaptive gain depending on the identification error which accelerated the convergence of the weights and promotes a faster convergence between the states of the uncertain system and the trajectories of the neural identifier.The second approach uses a time-dependent sigmoidal gain that forces the convergence of the identification error to an invariant set characterized by an ellipsoid.The generalized volume of this ellipsoid depends on the upper bounds of uncertainties,perturbations and modeling errors.The application of the invariant ellipsoid method yields to obtain an algorithm to reduce the volume of the convergence region for the identification error.Both adaptive algorithms are derived from the application of a non-standard exponential dependent function and an associated controlled Lyapunov function.Numerical examples demonstrate the improvements enforced by the algorithms introduced in this study by comparing the convergence settings concerning classical schemes with non-exponential continuous learning methods.The proposed identifiers overcome the results of the classical identifier achieving a faster convergence to an invariant set of smaller dimensions.

关键词： Exponential Lyapunov functions learning laws non-parametric identifier predefined convergence rate

Precipitation kinetics of carbides during cyclical and isothermal aging of 2.25Cr–1Mo steel and its effect on mechanical properties

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Journal of Iron and Steel Research(International) 2021年第10期28卷 1282-1290页

作者： Maribel Leticia Saucedo-Muñoz ESIQIE Instituto Politécnico NacionalMexico07300Mexico

The carbide precipitation was analyzed during aging of 2.25Cr–1Mo steel at 550℃.The as-received steel was aged in two different manners:the first treatment was an isothermal aging at 550℃ for time up to 1000 h,and the second one was carried out by a cyclical aging,which consisted of aging at 550℃ for 1 h,water quenching at room temperature and then newly heating at 550℃.This procedure was repeated up to 300 times.The M_(23)C_(6) and M6C carbide precipitation took place intragranularly and intergranularly for both aging treatments.The carbide coarsening was detected to occur with the increasing aging time.Nevertheless,the growth kinetics of precipitation occurred more rapidly in the case of cyclical aging.The specimen hardness decreased with the aging time in both cases;however,it occurred in shorter aging time for the cyclical aging.Nanoindentation testing indicated the increase in ductility with the aging time,and the cyclically aged specimens showed larger ductility than the isothermally aged specimens.

关键词： 2.25Cr-1Mo steel Precipitation Isothermal heating Cyclical heating Mechanical property

A graph-based representation of knowledge for managing land administration data from distributed agencies–A case study of Colombia

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Geo-Spatial Information Science 2022年第2期25卷 259-277页

作者： Luis M.Vilches-Blázquez Jhonny Saavedra Investigación en Computación Instituto Politécnico NacionalMexico CityMexico School of Land Surveying Geodesy and Mapping EngineeringUniversidad Politécnica de MadridMadridSpain

Multiple efforts have been performed worldwide around diverse aspects of land administra-tion.However,land administration data and systems’notorious heterogeneity remains a longstanding challenge to develop a harmonized vision.In this sense,the traditional Spatial Data Infrastructures adoption is not enough to overcome this challenge since data sources’heterogeneity implies needs related to harmonization interoperability,sharing,and integration in land administration development.This paper proposes a graph-based represen-tation of knowledge for integrating multiple and heterogeneous data sources(tables,shape-files,geodatabases,and WFS services)belonging to two Colombian agencies within a decentralized land administration scenario.These knowledge graphs are developed on an ontology-based knowledge representation using national and international standards for land administration.Our approach aims to prevent data isolation,enable cross-datasets integration,accomplish machine-processable data,and facilitate the reuse and exploitation of multi-jurisdictional datasets in a single approach.A real case study demonstrates the applicability of the land administration data cycle deployed.

关键词： Land administration knowledge graph ontology heterogeneity data integration

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船舶管路系统中与压力有关的模型研究

Journal of Marine Science and Application 2020年第2期19卷 266-274页

作者： Daniel Molina Pérez Lemuel C.Ramos-Arzola Amadelis Quesada Torres Departamento de Manufactura ESIME Unidad AzcapotzalcoInstituto Politécnico NacionalDF 02250 México CityMexico Departamento de Termofluidos ESIME Unidad AzcapotzalcoInstituto Politécnico NacionalDF 02250 México CityMexico

This paper aims to evaluate the feasibility of pressure-dependent models in the design of ship piping systems.For this purpose,a complex ship piping system is designed to operate in firefighting and bilge services through jet pumps.The system is solved as pressure-dependent model by the piping system analysis software EPANET and by a mathematical approach involving a piping network model.This results in a functional system that guarantees the recommendable ranges of hydraulic state variables(flow and pressure)and compliance with the rules of ship classification societies.Through this research,the suitability and viability of pressure-dependent models in the simulation of a ship piping system are proven.

关键词： Pressure-dependent models Ship piping systems Bilge systems Firefighting systems Piping network models

Morphological and biochemical effects of weekend alcohol consumption in rats: Role of concentration and gender

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World Journal of Hepatology 2018年第2期10卷 297-307页

作者： José A Morales-González María de Lourdes Sernas-Morales ángel Morales-González Laura Ligía González-López Eduardo Osiris Madrigal-Santillán Nancy Vargas-Mendoza Tomás Alejandro Fregoso-Aguilar Liliana Anguiano-Robledo Eduardo Madrigal-Bujaidar Isela álvarez-González Germán Chamorro-Cevallos Laboratorio de Medicina de Conservación Escuela Superior de Medicina Instituto Politécnico Nacional Escuela Superior de Cómputo Instituto Politécnico Nacional área Académica de Nutrición ICSa Universidad Autónoma del Estado de Hidalgo Depto. de Fisiología Laboratorio de Hormonas y Conducta ENCB campus Zacatenco Instituto Politécnico Nacional Laboratorio de Farmacología Molecular Sección de Estudios de Posgrado e Investigación Escuela Superior de Medicina-Instituto Politécnico Nacional Laboratorio de Genética Escuela Nacional de Ciencias Biológicas IPN Departamento de Farmacia Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional

AIM To examine the association between weekend alcohol consumption and the biochemical and histological alterations at two different concentrations of alcohol in both genders in rats.METHODS Wistar rats weighing 170-200 g were divided into groups as follows:(1) Control groups; and(2) weekend alcohol-consumption group: 2 d/weekly per 12 wk, at two different concentrations:(1) Group of males or females with a consumption of a solution of alcohol at 40%; and(2) group of males or females with a consumption of a solution of alcohol at 5%. At the end of the experiment, serum and liver samples were obtained. The following enzymes and metabolites were determined in serum: Alanine Aminotransferase(ALT), Aspartate Aminotransferase(AST), Lactate Dehydrogenase, and Gamma-Glutamyltransferase, and glucose, triglycerides, cholesterol, bilirubin, and albumin. Liver samples from each group were employed to analyze morphological abnormalities by light microscopy.RESULTS In all of the weekend alcohol-consumption groups, AST activity presented a significant, 10-fold rise. Regarding ALT activity, the groups with weekend alcohol consumption presented a significant increase that was six times greater. Bilirubin levels increased significantly in both groups of females. We observed a significant increase in the parameters of fatty change and inflammation due to weekend alcohol consumption. Only the group of females that consumed alcohol at 40% presented slight hepatocel ular disorganization CONCLUSION The results obtained herein provide solid evidence that weekend alcohol consumption gives rise to liver damage, demonstrated by biochemical and histological alterations, first manifested acutely, and prolonged weekend alcohol consumption can cause greater, irreversible damage.

关键词： Weekend alcohol consumption Liver morphology Transaminases Damage

Boron-containing compounds as labels,drugs,and theranostic agents for diabetes and its complications

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World Journal of Diabetes 2024年第6期15卷 1060-1069页

作者： Marvin A Soriano-Ursúa R Ivan Cordova-Chávez Eunice D Farfan-García George Kabalka Department of Physiology Escuela Superior de MedicinaInstituto Politécnico NacionalCiudad de México 11340Mexico Department of Physiology Instituto Politécnico NacionalMexico City 11340Mexico Department of Biochemistry Instituto Politécnico NacionalMexico City 11340Mexico Department of Chemistry The University of TennesseeKnoxvilleTN 37996United States

Diabetes is a disease with a high global burden.Current strategies have failed to limit the advancement and impact of the disease.Successful early diagnosis and treatment will require the development of new agents.In this sense,boroncontaining compounds have been reported as agents with the ability to reduce glycemia and lipidemia.They have also been used for labeling and measuring carbohydrates and other molecules linked to the initial stages of diabetes and its progression.In addition,certain boron compounds bind to molecules related to diabetes development and their biological activity in the regulation of elevated glycemia.Finally,it should be noted that some boron compounds appear to exert beneficial effects on diabetes complications such as accelerating wound healing while ameliorating pain in diabetic patients.

关键词： Boron Carbohydrates Metabolism Diabetes Boronodipyrromethene

Understanding root-zone soil moisture in agricultural regions of Central Mexico using the ensemble Kalman filter,satellite-derived information,and the THEXMEX-18 dataset

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International Journal of Digital Earth 2022年第1期15卷 52-78页

作者： Héctor Ernesto Huerta-Bátiz Daniel Enrique Constantino-Recillas Alejandro Monsiváis-Huertero Juan Carlos Hernández-Sánchez Jasmeet Judge Ramón Sidonio Aparicio-García Escuela Superior de Ingeniería Mecánica y Eléctrica Unidad Ticomán Instituto Politécnico NacionalMexico CityMexico Escuela Superior de Ingeniería Mecánica y Eléctrica Unidad Zacatenco Instituto Politécnico NacionalMexico CityMexico Tecnológico nacional de México-TESE EcatepecMexico Department of Agricultural and Biological Engineering University of FloridaGainesvilleFLUSA

An Ensemble Kalman Filter(EnKF)-based assimilation algorithm was implemented to estimate root-zone soil moisture(RZSM)using a Soil-Vegetation-Atmosphere Transfer(SVAT)model during a complete growing season of corn in Central Mexico.Synthetic and field soil moisture(SM)observations and NASA SMAP SM retrievals were used to understand the effect of vertically spatial updates and uncertainties in meteorological forcings on RZSM estimates.Assimilation of RZSM every 3 days using SM observations at 4 depths lowered the averaged standard deviation(ASD)and the root mean square error(RMSE)by 60%and 50%,respectively,compared to the open-loop ASD.The assimilation of synthetic SM at the top 0-5 cm obtained RZSM closer to observations compared to THEXMEX-18 SM measurements and SMAP SM retrievals.Differences between EnKF estimates and SM observations and SMAP SM retrievals are mainly due to misrepresentation of vegetation conditions.The results improved SM estimates up to 10-cm depth using SMAP SM retrievals;however,additional studies are needed to improve SM at deeper layers.The implemented methodology can estimate SM at the top 10 cm of the soil every 3 days to mitigate the impact of the climate change on agricultural production over rainfed areas,particularly in developing countries.

关键词： Root-zone soil moisture SVAT model ensemble kalman filter soil moisture active-Passive(SMAP)mission agricultural region THEXMEX-18 central Mexico

Universal Associated Legendre Polynomials and Some Useful Definite Integrals

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Communications in Theoretical Physics 2016年第8期66卷 158-162页

作者：陈昌远尤源陆法林孙东升董世海 School of Physics and Electronics Yancheng Teachers University CIDETEC Instituto Politécnico NacionalUnidad Profesional ALM

We first introduce the universal associated Legendre polynomials, which are occurred in studying the noncentral fields such as the single ring-shaped potential and then present definite integrals I;（a, τ） =∫;x;[P;（x）];/（1±x）;dx,a= 0, 1, 2, 3, 4, 5, 6, τ = 1, 2, 3, I;（b, σ） =∫;x;[P;（x）];/（1-x;）;dx,b = 0, 2, 4, 6, 8, σ = 1, 2, 3, and I;（c, κ）=∫;x;[P;（x）];/[（1-x;）;（1 ± x）]dx,c = 0, 1, 2, 3, 4, 5, 6, 7, 8, κ = 1, 2. The superindices "±" in I;（a, τ） and I;（c, κ） correspond to those of the factor（1 ± x） involved in weight functions. The formulas obtained in this work and also those for integer quantum numbers l′ and m’ are very useful and unavailable in classic handbooks.

关键词： universal associated-Legendre polynomials definite integral partial fraction expansion parity