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Two-stage Transient-stability-constrained Optimal Power Flow for Preventive Control of Rotor Angle Stability and Voltage Sags

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Journal of Modern Power Systems and Clean Energy 2024年第5期12卷 1357-1369页

作者： Jorge Uriel Sevilla-Romero Alejandro Pizano-Martínez Claudio Rubén Fuerte-Esquivel Reymundo Ramírez-Betancour the Faculty of Electrical Engineering Universidad Michoacana de San Nicolás de Hidalgo58030 MoreliaMéxico the department of Electrical Engineering Universidad of Guanajuato36787 SalamancaMéxico the department of Electrical and Electronic Engineering Universidad Juárez Autónoma de Tabasco86040 VillahermosaMéxico

In practice,an equilibrium point of the power system is considered transiently secure if it can withstand a specified contingency by maintaining transient evolution of rotor angles and voltage magnitudes within set bounds.A novel sequential approach is proposed to obtain transiently stable equilibrium points through the preventive control of transient stability and transient voltage sag(TVS)problems caused by a severe *** proposed approach conducts a sequence of non-heuristic optimal active power re-dispatch of the generators to steer the system toward a transiently secure operating point by sequentially solving the transient-stability-constrained optimal power flow(TSC-OPF)*** the proposed approach,there are two sequential projection stages,with the first stage ensuring the rotor angle stability and the second stage removing TVS in voltage *** both projection stages,the projection operation corresponds to the TSC-OPF,with its formulation directly derived by adding only two steady-state variable-based transient constraints to the conventional OPF *** effectiveness of this approach is numerically demonstrated in terms of its accuracy and computational performance by using the Western System Coordinated Council(WSCC)3-machine 9-bus system and an equivalent model of the Mexican 46-machine 190-bus system.

关键词： Dynamic security assessment transient stability transient voltage sag(TVS) optimal power flow(OPF)

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Interlayer distance effects on absorption coefficient and refraction index change in p-type double-δ-doped GaAs quantum wells

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Chinese Physics B 2019年第12期28卷 186-190页

作者： H Noverola-Gamas L M Gaggero-Sager O Oubram Instituto de Investigaciones en Ciencias Básicas y Aplicadas Universidad Autónoma del Estado de Morelos MorelosCuernavaca 62209Mexico Division Academica de Ingeniería y Arquitectura Universidad Juárez Autonoma de TabascoCunduacan 8660Mexico Centro de Investigación en Ingeniería y Ciencias Aplicadas Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico

In the framework of the Thomas–Fermi(TF) approach, a model for the p-type double-δ-doped(DDD) system in Ga As is presented. This model, unlike other works in the literature, takes into account that the Poisson equation associated with the system is nonlinear. The electronic structure is calculated for heavy and light holes. The changes in the electronic structure result of the distance d between the doped layers are studied. In particular, the relative absorption coefficient as well as the relative refractive index change is calculated as a function of the incident photon energy for heavy holes. The effect of the interlayer distance exhibits, in the absorption coefficient, a red shift of the peak position and a decrease in amplitude when the distance increases. In addition, the relative refractive index change node has a red shift as well as the interlayer distance increases. The calculations show that the effect of the separation between layers has a greater influence on the linear terms. These results are very important for theoretical calculations and engineering of optical and electronic devices based in δ-doped Ga As.

关键词： double delta-doping p-type GaAs layers electronic structure Thomas–Fermi approach nonlinear optical properties

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Numerical Study of the Distribution of Temperatures and Relative Humidity in a Ventilated Room Located in Warm Weather

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Computer Modeling in Engineering & Sciences 2020年第5期123卷 571-602页

作者： J.Serrano-Arellano J.M.Belman-Flores I.Hernández-Pérez K.M.Aguilar-Castro E.V.Macías-Melo F.Elizalde-Blancas J.M.Riesco-Ávila F.J.García-Rodríguez Instituto Tecnológico Superior de Huichapan El SaucilloHuichapan42411México universidad de Guanajuato Palo BlancoSalamanca36885México universidad juárez autónoma de tabasco CunduacánTabasco86690México Instituto Tecnológico de Celaya Col.FovisssteCelaya38010México

In the present study,an analysis of the heat and mass transfer in a ventilated cavity in a warm climate zone was carried out to analyze,among others,the temperatures and percentage of relative humidity(RH).The governing equations of the mathematical model were solved through the finite volume *** used the k-εturbulence mode to find the results of the variables of interest in seven climate records on a given *** velocity of the inlet flow of the air-H2O mixture was varied through the Reynolds number(Re)from 500 to *** outdoor weather conditions considered were solar radiation,ambient temperature,and *** was found that at low velocities,flow recirculation was formed inside the cavity which increased the temperature and concentration of *** Re=5000 the flow is predominantly forced,which tends to set the values of temperature and RH as 20°C and 20%*** values of the RH increase in the afternoon hours when the solar radiation decreases to the value of ***,the mass transfer through the values of Sh is maintained with similar values in the seven weather *** was concluded that when air conditioning supplies air at speeds higher than 0.26 m/s at low temperatures it produces cooling with low RH,this causes discomfort,illness and/or discomfort to the users.

关键词： Heat transfer mass transfer solar radiation turbulence

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Numerical Simulation of Bed Load and Suspended Load Sediment Transport Using Well-Balanced Numerical Schemes

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Communications on Applied Mathematics and Computation 2023年第2期5卷 885-922页

作者： J.C.González-Aguirre J.A.González-Vázquez J.Alavez-Ramírez R.Silva M.E.Vázquez-Cendón División Acádemica de Ciencias Básicas Universidad Juárez Autónoma de TabascoCarr.Cunduacán-Jalpa de Mendéz KM.1CP 86690CunduacánTabascoMexico universidad autónoma Metropolitana-Unidad Iztapalapa Av.San Rafael Atlixco no.186Mexico CityMexico Instituto de Ingeniería Universidad Nacional Autónoma de México04510 Mexico CityMexico departamento de Matemática Aplicada Universidade de Santiago de Compostela15706 Santiago de CompostelaSpain

Sediment transport can be modelled using hydrodynamic models based on shallow water equations coupled with the sediment concentration conservation equation and the bed con-servation *** complete system of equations is made up of the energy balance law and the Exner *** numerical solution for this complete system is done in a seg-regated ***,the hyperbolic part of the system of balance laws is solved using a finite volume *** ways to compute the numerical flux have been considered,the Q-scheme of van Leer,the HLLCS approximate Riemann solver,and the last one takes into account the presence of non-conservative products in the *** discretisation of the source terms is carried out according to the numerical flux *** the second stage,the bed conservation equation is solved by using the approximation computed for the system of balance *** numerical schemes have been validated making comparisons between the obtained numerical results and the experimental data for some physical *** numerical results show a good agreement with the experimental data.

关键词： Sediment transport Suspended load Bed load Finite volume method Numerical simulation Well-balanced schemes

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Level of Treatment Adherence in Patients with Type 2 Diabetes in Primary Care

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Journal of Biosciences and Medicines 2021年第10期9卷 146-155页

作者： Muñoz-Sol Mario Enrique Guzmán-Priego Crystell Guadalupe Albarrán-Melzer Jorda Aleiria Laboratory of Cardiometabolism Universidad Juárez Autónoma de Tabasco División Académica de Cienicas de la Salud Tabasco México

Introduction: The glycemic control of type 2 diabetes is a very important challenge that requires a multidisciplinary group of specialists, an adequate psychosocial environment and family support and searching for better measures for the control and prevention of complications, which encourages the patient to improve his lifestyle. Method: The analysis was made with two primary care medical units, the Mutual Aid Group (GAM) from the Los Pinos Medical center, and the Chronic disease Specialized Medical Unit (UNEME EC), which provided integral care in the municipality of San Cristóbal de Las Casas, Chiapas. A sample of 138 patients was obtained through a random sampling with 95% confidence and a margin of error of ±5. The recollection of data was made with the application of the questionnaire “Lifestyle and adherence to pharmacological treatment in patients with type 2 diabetes, which consists of four sections that evaluate 1) socio-demographic data;2) anthropometric and clinical;Pharmacological adherence with Morisky’s 8-item questionnaire (MMSA-8);3) Lifestyle: with the instrument to Measure Lifestyle in Diabetics (IMEVID). Results: 37.6% had an HbA1c lesser than 7%, A prevalence of 50.7% was obtained in patients adhering to the pharmacological treatment, and 39.8% patients with a favorable lifestyle. The association of the patients’ results with an adequate glycemic control demonstrated by an HbA1C lesser than 7% was obtained through Student’s T test in which these patients are related with a better score on questionnaires by IMEVID and MMAS-8. Conclusions: The units with integral care and multidisciplinary treatment are fundamental in the care of patients with type 2 diabetes;the use of questionnaires such as IMEVID or MMAS-8 is useful in the daily clinical practice.

关键词： Diabetes Pharmacological Adherence Lifestyle Glycemic Control Multidisciplinary Care

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Preparation of Rod-like Aluminum Doped Zinc Oxide Powders by Sol-gel Technique Using Metal Chlorides and Acetylacetone Precursors

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Journal of Wuhan University of Technology(Materials Science) 2018年第6期33卷 1293-1297页

作者： KESHTKAR Javad VARGAS GARCIA Jorge Roberto GALAVIZ PErez Jorge MARTINEZ TRINIDAD José Escuela Superior de Ingenieria Mecánica y Eléctrica Instituto Politécnico NacionalMéxico07738CDMXMéxico Escuela Superior de Ingenieria Quimica e Industrias Extractivas Instituto Politécnico NacionalMéxico07738CDMXMéxico universidad juárez autònoma de tabasco DivisiònAcadémica Multidisciplinaria de Jalpa de MéndezRibera AltaJalpa de MéndezTabasco86205México

Al-doped ZnO(AZO) powders were prepared by using metal chloride precursors and the sol-gel technique. IR peaks observed at 1590 cm-1 and 1620 cm-1indicated the formation of metal chelate as a consequence of the addition of acetylacetone to the metal chloride solution. TG-DSC analysis of the AZO gels confirmed the formation of metal chelate as evidenced by the development of several weight loss peaks accompanied by the introduction of new endothermic peaks. The resulting AZO gels were annealed at 500, 600, and 800 ℃ to study the effect of annealing temperature. XRD and SEM results showed that crystallization of AZO gels takes place around 600 ℃. Hexagonal wurtzite structure was identified as the main phase for all the samples. In addition, small shift of the XRD(002) peak coupled with XPS results from the AZO powders confirmed the successful doping of the ZnO powders. Micron sized rod-like AZO powders were uniform in dimension and morphology and remained stable even at 800 ℃.

关键词： aluminum doped ZnO rod-like metal chloride sol gel acetylacetone

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Rainfall Trend Analysis in the City of Villahermosa, Mexico

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Journal of Geological Resource and Engineering 2019年第1期7卷 9-16页

作者： Ana Victoria Gómez Alejandro Heliodoro Daniel Cruz Suárez División Académica de Ciencias Básicas Universidad Juárez Autónoma de Tabasco Cunduacán 86690 México

In this paper, a study by means of linear regression of rainfall in Villahermosa is proposed, within the study area 5 meteorological stations distributed in the city were analyzed because it is one of the most populated areas of the state, once estimated the data, the non-parametric Mann-Kendall test was used to determine increasing or decreasing linear trends in precipitation. To determine the usefulness of statistical inference, the linear correlation coefficient (r) was calculated, which was 0.86 on average. Statistical efficiency (E) was also calculated, which in all the cases analyzed suggests the viability of statistical inference. As a result of this analysis, a complete rainfall database is presented and evaluated for increasing or decreasing trends for the 1980-2010 period.

关键词： Rainfall linear regression Mann Kendall trend analysis.

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Abundance of White-fronted Parrots and diet of an urban parrot assemblage(Aves:Psittaciformes)in a green Neotropical city

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Avian Research 2022年第1期13卷 36-42页

作者： CristelAlvarez-Castillo Ian MacGregor-Fors Stefan LArriaga-Weiss Claudio Mota-Vargas Diego Santiago-Alarcon Biología y Conservación de Vertebrados Instituto de EcologíaA.C.-CONACYTXalapaMexico Biological and Environmental Sciences University of HelsinkiLahtiFinland División Académica de Ciencias Biológicas Universidad Juárez Autónoma de TabascoVillahermosaMexico Biología Evolutiva Instituto de EcologíaA.C.-CONACYTXalapaMexico department of Integrative Biology University of South FloridaTampaUSA

Urban ecosystems are evolutionarily recent novel environments acting as biodiversity *** birds are considered successful urban adapters mainly due to their generalist feeding and opportunistic behavior,allowing them to occupy environments from cold temperate to dry xeric ***,it is important to understand how these species interact in the urban *** studied the interannual(2013–2016)abundance of the White-fronted Parrot(Amazona albifrons)in the Neotropical cities of Xalapa and Coatepec,in Central Veracruz,Mé***,we studied the feeding ecology during 13 months of 6 parrot species detected in the city of *** abundance of the White-fronted Parrot was significantly higher in Xalapa than in Coatepec,and it was homogeneous across ***-native plants represented 30–41%of Psittacidae diets in Xalapa,where seeds were the most commonly consumed *** recorded the highest Psittacidae species richness and highest diet overlap among species by the end of the dry season(April–May).The White-fronted Parrot had the highest plant richness in its diet,followed by the Monk Parakeet(Myiopsitta monachus)and the Green Parakeet(Psittacara holochlorus);yet,the White-fronted Parrot had a specialized diet dominated by two plant species(Grevillea robusta and Ficus aurea).The diet overlap among the three above-mentioned parrot species was not significantly different to a null model,where the White-fronted Parrot and the Monk Parakeet overlapped during the months of February,April,june,and *** White-fronted Parrot is an urban adapter that has successfully expanded its geographic range via natural means and by human *** invasive Monk Parakeet is currently restricted to one park in Xalapa,and it has remained in that stage for many years(i.e.,pre-expansion phase).Exotic plant species in Xalapa represent∼55%of the woody vegetation,some of which have longer flowering and fruiting periods that may have aided the s

关键词： Biological invasions Feeding ecology Population biology Psittacidae Urban ecology

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A charged star with geometric Karmarkar condition

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Communications in Theoretical Physics 2023年第8期75卷 139-149页

作者： Gabino Estevez-delgado Joaquin Estevez-delgado Rafael Soto-Espitia Antonio Rendón Romero Jorge Mauricio Paulin-Fuentes Facultad de Químico Farmacobiología de la universidad Michoacana de San Nicolás de Hidalgo Facultad de Ciencias Físico Matemáticas de la universidad Michoacana de San Nicolás de Hidalgo Edificio BCiudad Universitaria Facultad de Ingeniería Civil de la universidad Michoacana de San Nicolás de Hidalgo Edificio A Ciudad Universitaria Facultad de Ingeniería Mecánica de la universidad Michoacana de San Nicolás de Hidalgo Edificio W Ciudad Universitaria División Académica de Ciencias Básicas de la universidad juárez autónoma de tabasco

In this paper,we analyse an analytical solution of the Einstein–Maxwell field equations that considers matter with anisotropic pressures in a static and spherically symmetric *** report the manner in which we obtained the solution,which is by means of the Karmarkar *** the model,we assume a state equation that describes the interaction of matter from quarks P=(c^(2)ρ-4B_(g))/3 and we consider the presence of electric charge,which can generate that the radial and tangential pressures are not *** a graphic manner,we analyse the physical properties of the model,taking as the observational data those of mass 1M⊙and radius7.69 km which were reported for the star Her *** charge values are found between 5.57×10^(18)C≤Q≤1.31×10^(20)C and the interval of the Bag constant Bg∈[118.7,122.13]MeV/fm^(3).Also,we show the stability of the configuration by means of the static stability criteria of Harrison–Zeldovich–Novikov((?M)/?ρc>0),as well as in regards to infinitesimal radial adiabatic perturbation,since the adiabatic indexγ>3.3 which guarantees the stability of the solution.

关键词： general relativity exact solutions anisotropic fluid Karmarkar condition

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Recent trends and technical advancements in biosensors and their emerging applications in food and bioscience

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Food Bioscience 2022年第3期47卷 1023-1050页

作者： Oluwatosin E.Bankole deepak Kumar Verma Mónica L.Chávez González juan Guzmán Ceferino JoséSandoval-Cortés Cristóbal N.Aguilar department of Chemical Sciences Faculty of Science and Science EducationAnchor UniversityLagos StateNigeria Agricultural and Food Engineering department Indian Institute of Technology KharagpurKharagpur721302West BengalIndia Bioprocesses Research Group Food Research DepartmentSchool of ChemistryUniversidad Autonoma de CoahuilaUnidad Saltillo25280CoahuilaMexico Los Ríos Multidisciplinary Academic Division Universidad Juárez Autónoma de TabascoTabascoMexico department of Analytical Chemistry School of ChemistryUniversidad Autonoma de CoahuilaUnidad Saltillo25280CoahuilaMexico

Biosensor development has recently advanced as a result of their strong and indisputable uses as analytical methods in a variety of sectors,including medicine,food industry,environmental monitoring,metabolism,agriculture,military,and *** popularity of biosensors as devices for a variety of applications may be ascribed to their distinct advantages of fast or rapid analysis,high sensitivity,minimal sample demand and preparation,and no need for the specific skill of operation that traditional analytical procedures *** attempted to update earlier studies in this study by incorporating other materials that have been in use but have received less attention,such as carbon nano-onions(CNOs),metal-organic frameworks(MOFs),and biopolymers for biosensor manufacturing and design based on their unique *** assessment also took into account applicable applications in many *** considerable progress has been made in the application of biosensors,there is still a need for research development and enhancement,particularly in transforming most of the laboratory experiments that have already been published into portable on-site and implementable in the public domains.

关键词： Biosensors Nanotechnology Nano-materials Food quality and safety Food snd biomedical industry Industrial application

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