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Atmospheric-pressure dielectric barrier discharge generation by a full-bridge flying capacitor multilevel inverter

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Plasma Science and Technology 2017年第7期19卷 40-49页

作者： Rosendo PE?A-EGUILUZ José A LóPEZ-FERNáNdeZ Antonio MERCADO-CABRERA Bethsabet JARAMILLO-SIERRA Régulo LóPEZ-CALLEJAS Benjamín RODRíGUEZ-MéNdeZ Raúl VALENCIA-ALVARADO Allan A FLORES-FUENTES Arturo E MU?OZ-CASTRO Plasma Physics Laboratory Instituto Nacional de Investigaciones Nucleares Tecnológico de estudios superiores de Tianguistenco Universidad Autónoma del Estado de México

A new configuration of a resonant full-bridge flying capacitor multicell inverter has been designed and constructed with the aim of achieving an extended output voltage frequency range with low harmonic distortion and reduced semiconductor commutation losses. This configuration was tested as a power supply for two different coaxial dielectric barrier discharge reactors, one of them employed for electric characterization and the other one for inorganic compound elimination in an aqueous solution. Two different gas mixtures, 90% Ar-10% 02 and 80% Ar-20% 02, were individually supplied during the experiments; the results showed a high- efficiency removal of meta-cresol （m-cresol） to the order of 98%, which was obtained by adding more oxygen to the plasma gas mixture.

关键词： plasma applications water pollution plasma sources power supply circuits electricdischarges

Adsorption of cobalt by using inorganic components of sediment samples from water bodies

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International Journal of Sediment Research 2021年第4期36卷 524-531页

作者： Rocío Montes de Oca-Palma Marcos Solache-Ríos Melania Jiménez-Reyes José Juan García-Sánchez Perla Tatiana Almazán-Sánchez Instituto Nacional de Investigaciones Nucleares Departamento de Química Tecnológico de estudios superiores de Jocotitlán Cátedras CONACyT-Instituto Nacional de Investigaciones Nucleares

The adsorption of cobalt ions was evaluated using sediment samples from water bodies to investigate the adsorption properties of sediment and the behavior of these natural materials in the presence of nuclear and industrial waste. The two sediments(S1 and S2) were treated to eliminate humic and fulvic acids and then they were characterized by several techniques. The minerals found in both the sediments(X-ray diffraction) were quartz and albite; plus, goethite and muscovite in S1, and kaolinite and montmorillonite in S2. Point of zero charge(PZC) of S1 and S2 was 6.00 and 5.22, respectively. The specific area of S1(63.3 m2/g) is higher than S2(1.5 m2/g). Adsorption kinetics data for S1 and S2 were best fitted to the pseudo second-order model. The removal efficiency of S1 for cobalt was 96% with an adsorption capacity(qe) of 0.93 mg/g, and for S2 was 45% with a qeof 0.40 mg/g. The experimental data of the adsorption isotherms were adjusted to Langmuir and Freundlich models for S1 and S2, respectively. The thermodynamic parameters(enthalpy, entropy, and Gibb’s free energy) indicated that the adsorption processes were endothermic, spontaneous, and chemisorption mechanism. The results show that the adsorption capacities of the sediments depend on their composition. These water sediments have important adsorption properties for cobalt, and they can be used in the treatment of nuclear and industrial aqueous wastes.

关键词： Water-body sediment Cobalt ions Adsorption

Precipitation analysis of as-cast HK40 steel after isothermal aging

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1125-1133页

作者： M.L. Saucedo-Munoz A. Ortiz-Mariscal V.M. Lopez-Hirata J.D. Villegas-Cardenas Orlando Soriano-Vargas Erika O. Avila-Davila Instituto Politecnico Nacional (ESIQIE) Apdo. Postal 118-395 Mexico D.F. 07300 Universidad Politecnica Metepec y Tultitlan Edo. Mex. Mexico Tecnológico de estudios superiores de Jocotitlan Jocotitlan Edo. Mex. Mexico

As-cast HK40 steel was aged at 700, 800, or 900℃ for times as long as 2000 h. Microstructural characterization showed that the primary M_7C_3 carbide network contained a substantial content of manganese, in agreement with the microsegregation of manganese calculated by Thermo-Calc using the Scheil–Gulliver module. The dissolution of primary carbides caused the solute supersaturation of austenite and subsequent precipitation of fine M_(23)C_6 carbides in the austenite matrix for aged specimens. During prolonged aging, the carbide size increased with increasing time because of the coarsening process. A time–temperature–precipitation diagram for M_(23)C_6 carbides was calculated using the Thermo-CalcPRISMA software; this diagram showed good agreement with the experimental growth kinetics of precipitation. The fine carbide precipitation caused an increase in hardness; however, the coarsening process of carbides promoted a decrease in hardness. Nanoindentation tests of the austenite matrix indicated an increase in ductility with increasing aging time.

关键词： as-cast HK40 steel carbide precipitation aging precipitation simulation

HVSR analysis of pumice sands for sediment depth characterization:A case study for Guadalajara,Mexico

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 577-591页

作者： Hafid Salgado M. Alejandro Ramírez-Gaytan Adolfo Preciado Christian R.Escudero departamento de Ciencias Exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico departamento de Ciencias Computacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico departamento del Hábitat y desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The horizontal to vertical spectral ratio(HVSR)methodology is used here to characterize pumice soils and to image the three-dimensional surface geometry of Guadalajara,*** to other Latin American cities,Guadalajara is exposed to high seismic risk,with the particularity of being the largest urban settlement in Latin America built on pumice *** has not yet been tested to characterize subsoil depths in pumice *** to the questionable use of traditional geotechnical tests for the analysis of pumice soils,HVSR provides an alternative for its characterization without altering its fragile and porous *** this work,resonance frequency(F0)and peak amplitude(A0)are used to constrain the depth of the major impedance contrast that represents the interface between bedrock and pumice *** were compared with borehole depths and other available geotechnical and geophysical data and show good *** of the profiles estimated on the riverbanks that cross the city,reveals different subsoil thickness that could have an impact on different site responses on riverine areas to an eventual *** and academic efforts are combined in this work to characterize depth sediments,an important parameter that impacts the regulations for construction in the city.

关键词： subsoil of Guadalajara shallow soil thickness bedrock depth pumice soil characterization

Distributed Monitoring of Power System Oscillations Using Multiblock Principal Component Analysis and Higher-order Singular Value decomposition

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 818-828页

作者： Arturo Román-Messina Alejandro Castillo-Tapia David A.Román-García Marcos A.Hernández-Ortega Carlos A.Morales-Rergis Claudia M.Castro-Arvizu Center for Research and Advanced Studies(CINVESTAV)of the National Polytechnic Institute of Mexico GuadalajaraJal.45017Mexico Instituto Tecnológico y de estudios superiores de Monterrey GuadalajaraJal.45070Mexico Autonomous University of Guadalajara GuadalajaraJal.45129Mexico Centro de Enseñanza Técnica Industrial and he is also with UAGGuadalajaraJal.44638Mexico

The primary goal in the analysis of hierarchical distributed monitoring and control architectures is to study the spatiotemporal patterns of the interactions between areas or *** this paper,a novel conceptual framework for distributed monitoring of power system oscillations using multiblock principal component analysis(MB-PCA)and higher-order singular value decomposition(HOSVD)is proposed to understand,characterize,and visualize the global behavior of the power *** proposed framework can be used to evaluate the influence of a given area or utility on the oscillatory behavior,uncover low-dimensional structures from high-dimensional data,and analyze the effects of heterogeneous data on the modal characteristics and interpretation of power *** metrics are then investigated to examine the relationships between the dynamic patterns and participation of individual data blocks in the global behavior of the *** application of these techniques is demonstrated by case studies of two systems:a 14-machine test system and a 5449-bus 635-generator equivalent model of a large power system.

关键词： Distributed monitoring multiblock principal component analysis(MB-PCA) higher-order singular value decomposition(HOSVD) Tucker decomposition

Penrose Transform on Induced <i>D<sub>G/H</sub></i>-Modules and Their Moduli Stacks in the Field Theory

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Advances in Pure Mathematics 2013年第2期3卷 246-253页

作者： Francisco Bulnes department of Research in Mathematics and Engineering Tecnológico de Estudios Superiores de Chalco Chalco Mexico

We consider generalizations of the Radon-Schmid transform on coherent DG/H-Modules, with the intention of obtaining the equivalence between geometric objects (vector bundles) and algebraic objects (D-Modules) characterizing conformal classes in the space-time that determine a space moduli [1] on coherent sheaves for the securing solutions in field theory [2]. In a major context, elements of derived categories like D-branes and heterotic strings are considered, and using the geometric Langlands program, a moduli space is obtained of equivalence between certain geometrical pictures (non-conformal world sheets [3]) and physical stacks (derived sheaves), that establishes equivalence between certain theories of super symmetries of field of a Penrose transform that generalizes the implications given by the Langlands program. With it we obtain extensions of a cohomology of integrals for a major class of field equations to corresponding Hecke category.

关键词： Penrose Transform Coherent G-Quasi-Equivariant D-Modules Hecke Sheaf Moduli Stacks Moduli Spaces

derived Categories in Langlands Geometrical Ramifications: Approaching by Penrose Transforms

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Advances in Pure Mathematics 2014年第6期4卷 253-260页

作者： Francisco Bulnes Research department in Mathematics and Engineering Tecnológico de Estudios Superiores de Chalco Chalco Mexico

Some derived categories and their deformed versions are used to develop a theory of the ramifications of field studied in the geometrical Langlands program to obtain the correspondences between moduli stacks and solution classes represented cohomologically under the study of the kernels of the differential operators studied in their classification of the corresponding field equations. The corresponding D-modules in this case may be viewed as sheaves of conformal blocks (or co-invariants) (images under a version of the Penrose transform) naturally arising in the framework of conformal field theory. Inside the geometrical Langlands correspondence and in their cohomological context of strings can be established a framework of the space-time through the different versions of the Penrose transforms and their relation between them by intertwining operators (integral transforms that are isomorphisms between cohomological spaces of orbital spaces of the space-time), obtaining the functors that give equivalences of their corresponding categories.(For more information,please refer to the PDF version.)

关键词： Geometrical Langlands Correspondence Hecke Categories Moduli Stacks Penrose Transforms Quasi-Coherent Sheaves

Maize seed coatings and seedling sprayings with chitosan and hydrogen peroxide:their influence on some phenological and biochemical behaviors

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第2期14卷 87-96页

作者： Eva-Guadalupe LIZRRAGA-PAULíN Susana-Patricia MIRANDA-CASTRO Ernesto MORENO-MARTíNEZ Alma-Virginia LARA-SAGAHóN Irineo TORRES-PACHECO Laboratorio de Biotecnología Facultad de Estudios Superiores CuautitlánCampo 1Universidad Nacional Autónoma de MéxicoEstado de México 54740México Unidad de Investigación en Granos y Semillas Facultad de Estudios Superiores CuautitlánCentro de Asimilación TecnológicaUniversidad Nacional Autónoma de MéxicoEstado de México 54740México CA Ingeniería de Biosistemas División de Investigación y PosgradoFacultad de IngenieríaUniversidad Autónoma de QuerétaroQuerétaro 76010México

Objective： To evaluate the effect of chitosan （CH） and hydrogen peroxide （H2O） seed coatings and seedling sprinklings on two different maize varieties by measuring their phenology, the H202 presence, the catalase （CAT） activity, and the protein quantity. Methods： Seven groups of ten seeds for each maize variety were treated with CH （2% （20 g/L） and 0.2% （2 g/L）） or H2O2 （8 mmol/L） by coating, sprinkling, or both. Germination and seedling growth were measured. One month after germination, the presence of H202 in seedlings in the coated seed treatments was evaluated. Protein content and CAT activity were determined under all treatments. Results： H2O2 seed coating en- hanced the germination rate and increased seedling and stem length in the quality protein maize （QPM） variety. Seedlings had a higher emergence velocity under this treatment in both varieties. CH and H2O2 sprinklings did not have an effect on seedling phenology. Exogenous application of H2O2 promoted an increase of endogenousH2O2. OH and H2O2seedling sprinkling increased the protein content in both maize varieties, while there was no significant effect on the CAT activity of treated seeds and seedlings. Conclusions： CH and H2O2 enhance some phenological and biochemical features of maize depending on their method of application.

关键词： Zea mays Chitosan Hydrogen peroxide Phenology Catalase Protein

Analysis of Machine Learning Techniques Applied to the Classification of Masses and Microcalcification Clusters in Breast Cancer Computer-Aided detection

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Journal of Cancer Therapy 2012年第6期3卷 1020-1028页

作者： Edén A. Alanís-Reyes José L. Hernández-Cruz Jesús S. Cepeda Camila Castro Hugo Terashima-Marín Santiago E. Conant-Pablos Evolutionary Computation Research Chair Instituto Tecnológico y de Estudios Superiores de Monterrey Monterrey México.

Breast cancer is one of the most common and deadliest types of cancer among women and early detection is of major importance to decrease mortality rates. Microcalcification clusters and masses are two major indicators of malignancy in the early stages of this disease, when mammography is typically used as the screening technology. Computer-Aided Diagnosis (CAD) systems can support the radiologists’ work, by performing a double-reading process, which provides a second opinion that the physician can take into account in the detection process. This paper presents a CAD model based on computer vision procedures for locating suspicious regions that are later analyzed by artificial neural networks, support vector machines and linear discriminant analysis, to classify them into benign or malignant, based on a set of features that are extracted from lesions to characterize their visual content. A genetic algorithm is used to find the subset of features that provide the greatest discriminant power. Our results show that the SVM presented the highest overall accuracy and specificity for classifying microcalcification clusters, while the NN outperformed the rest for mass-classification in the same parameters. Overall accuracy, sensitivity and specificity were measured.

关键词： Computer-Aided Diagnosis Breast Cancer detection Breast Cancer Diagnosis Mass-Segmentation Calcification Segmentation Digital Mammography