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Evaluation of the Minimum Size of a Window for Harmonics Signals

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Journal of Signal and Information Processing 2016年第4期7卷 175-191页

作者： josé Manuel Alvarado reyes Catalina Elizabeth Stern Forgach ) Mexico City Mexico

Windowing applied to a given signal is a technique commonly used in signal processing in order to reduce spectral leakage in a signal with many data. Several windows are well known: hamming, hanning, beartlett, etc. The selection of a window is based on its spectral characteristics. Several papers that analyze the amplitude and width of the lobes that appear in the spectrum of various types of window have been published. This is very important because the lobes can hide information on the frequency components of the original signal, in particular when frequency components are very close to each other. In this paper it is shown that the size of the window can also have an impact in the spectral information. Until today, the size of a window has been chosen in a subjective way. As far as we know, there are no publications that show how to determine the minimum size of a window. In this work the frequency interval between two consecutive values of a Fourier Transform is considered. This interval determines if the sampling frequency and the number of samples are adequate to differentiate between two frequency components that are very close. From the analysis of this interval, a mathematical inequality is obtained, that determines in an objective way, the minimum size of a window. Two examples of the use of this criterion are presented. The results show that the hiding of information of a signal is due mainly to the wrong choice of the size of the window, but also to the relative amplitude of the frequency components and the type of window. Windowing is the main tool used in spectral analysis with nonparametric periodograms. Until now, optimization was based on the type of window. In this paper we show that the right choice of the size of a window assures on one hand that the number of data is enough to resolve the frequencies involved in the signal, and on the other, reduces the number of required data, and thus the processing time, when very long files are being analyz

关键词： Minimum Size of a Window Windowing Spectral Resolution

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

Primary maxillary chondrosarcoma: A case report

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World Journal of Clinical Cases 2020年第1期8卷 126-132页

作者： Juan Carlos Cuevas-González Jesús Oscar reyes-Escalera joséLuis González Celeste Sánchez-Romero León Francisco Espinosa-Cristóbal Simón Yobanny reyes-López Karla Lizette Tovar Carrillo Alejandro Donohue Cornejo Stomatology Department Biomedical Sciences InstituteAutonomous University of Ciudad JuárezCiudad Juárez 32310Mexico Maxillofacial Surgery Department Faculty of DentistryJuarez University of the State of DurangoDurango 34000Mexico Madero Pathology Laboratory Durango 34000Mexico Molecular Pathology Area Faculty of DentistryUniversity of the RepublicMontevideo 10000Uruguay

BACKGROUND Sarcomas of the head and neck region are rare tumors,constituting less than 1%of malignant neoplasms in this area,of which few cases(20%)originate from bone or *** is a malignant neoplasm that develops in bone,with a predilection for the pelvis,chest wall,and scapula,and is uncommon in the maxilla and *** this type of lesion has locally aggressive behavior,destroying the affected bone,it can metastasize when it is not diagnosed early and compromise the patient's *** SUMMARY On intraoral examination of a 32-year-old female with a tumor in the middle third of the face,a well-defined rise in volume of approximately 3 cm in diameter was *** tomography with 3-dimensional reconstruction was performed,and we observed that the osteolytic lesion affected the vestibular cortex as the palatal *** and eosin staining revealed an appearance that was similar to mature hyaline cartilage,hypercellularity,nuclear and cellular pleomorphism,and multinucleated cells,with significant *** Determination of the clinical and histopathological characteristics of rare neoplasms in the maxillofacial region,such as chondrosarcomas,allows the pathologist and surgeon to make the appropriate therapeutic decisions,optimizing the patient’s prognosis.

关键词： Chondrosarcoma Rare neoplasms Maxillofacial region Case report

Optimization of Parametric Periodograms for the Study of Density Fluctuations in a Supersonic Jet

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Journal of Signal and Information Processing 2013年第4期4卷 439-444页

作者： Catalina Elizabeth Stern Forgach josé Manuel Alvarado reyes Facultad de Ciencias Universidad Nacional Autónoma de México México City México

In our research on the density fluctuations of a supersonic jet we were confronted with a quite difficult problem. In the power spectrum obtained either with a spectrum analyzer, the peaks of the two of the modes that we wanted to identify overlapped. We needed to find a signal processing method that would resolve the two main frequencies. We made a thorough investigation of several methods and thought that parametric periodograms were the appropriate tool. The use of parametric periodograms in signal processing requires constant training. The proper application of this tool depends on the determination of the number of parameters that has to be used to best model a real signal. The methods generally used to determine this number are subjective, depending on trial and error and on the experience of the user. Some of these methods rely on the minimization of the estimated variance of the linear prediction error , as a function of the number of parameters n. In many cases, the graph vs n doesn’t have a minimum, and the methods cannot be used. In this paper, we show that there is a strong relationship between and the frequency resolution . That is, as we modify , we obtain graphs of vs n that present at least one minimum. The spectrum obtained with this optimal number of parameters, always reproduces the frequency information of the original signal. In this paper, we present basically the signal processing of the data obtained in a Rayleigh scattering experiment on a supersonic jet that has also been designed by the authors.

关键词： Parametric Periodograms Density Fluctuations Supersonic Jet

Effect of a bacterial inoculum and additive on dry matter in situ degradability of sugarcane silage

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Journal of Integrative Agriculture 2015年第3期14卷 497-502页

作者： josé A reyes-Gutiérrez Oziel D Montaez-Valdez Ramón Rodríguez-Macias Mario Ruíz-López Eduardo Salcedo-Pérez Cándido E Guerra-Medina South University Center University of Guadalajara University Center for Biological and Agricultural Science University of Guadalajara South Coast University Center University of Guadalajara

The objective of this study was to evaluate the effect of adding a bacterial inoculum and a handmade additive to sugarcane silage（SCS） on the in situ digestibility of dry matter（DM）. The treatments were： T1） sugarcane silage（SCS） and T2） sugarcane silage with 1% inoculum and 1% additive（SCS＋）. The bacterial inoculum consisted of 10.0% molasses, 1.0% yogurt, 5.0% chicken manure, 0.5% urea, and 83.0% water, and the additive was formulated with 1.0% urea, 0.1% ammonium sulfate, and 0.25% phosphorus. In situ dry matter digestibility（DMD） was determined using the nylon bag technique with four cows equipped with ruminal fistulas. Cows were fed with ensiled sugarcane supplemented with 1 kg of commercial concentrate. 5 g of ground sample for each sugarcane treatment were weighted in nylon bags and incubated for 4, 8, 12, 24, 48, and 72 h in a completely randomized design with six replicates. The DMD（%） was higher（P〈0.05） for SCS＋ for all incubation times when compared with SCS. There were no differences in ruminal p H between the treatments for all the incubation times. The data suggested that the sugarcane silage with bacterial inoculum and additive could be an alternative for providing forage for ruminants during the season of low growth and quality grass.

关键词： sugarcane silage degradability bacterial cows

Dehydration of Agro Products in a Hybrid Solar Dryer Controlled through a Fuzzy Logic System

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International Journal of Modern Nonlinear Theory and Application 2014年第3期3卷 66-76页

作者： Alejandro reyes Francisco Cubillos Andrea Mahn josé Vásquez Departamento de Ingeniería Química Universidad de Santiago de Chile Santiago Chile

Drying is one of the most energy-intensive processes in agro-products industry. For this reason, using solar energy appears as an attractive not polluting alternative to be used in drying processes. However, the daily and seasonal fluctuations in the radiation level require using energy accumulators with phase change materials (paraffin wax), to have a continuous drying processes. In hybrid solar dryers with energy accumulation system, a control system is essential to coordinate the control valves that allow the income of air that comes from the solar panel or from the energy accumulator. In this work, we implemented an advances multivariable control system that uses fuzzy logic in the hybrid solar dryer. The dryer includes an energy accumulator panel with paraffin wax as phase change material. The input variables were ambient temperature and solar radiation, both not controllable. The controlled variables were the opening level of the solar panel and accumulator energy valves. The control program consisted in an algorithm implemented with the “Fuzzy” toolbox in Matlab. Data were acquired with OPTO 22. The control system performed adequately when used to dehydrate mushroom slices and plums. Closing or opening the respective valves as a response to the variations of solar radiation and ambient air temperature allowed optimizing the use of solar energy.

关键词： Hybrid Solar Dryer Fuzzy Logic Control System Mushroom Plums

A Transactive Energy Model for Smart Metering Systems Using Blockchain

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CSEE Journal of Power and Energy Systems 2021年第5期7卷 943-953页

作者： Juan C.Olivares-Rojas Enrique reyes-Archundia jose A.Gutierrez-Gnecchi Ismael Molina-Moreno Jaime Cerda-Jacobo Arturo Mendez-Patino National Technological Institute of Mexico/Technological Institute of Morelia-Division of Graduate Studies and Research MoreliaMichoacan 58120Mexico. School of Electrical Engineering Michoacan University of San Nicolas de HidalgoMorelia 58030.Mexico

The lowering cost of electricity generation technologies by renewable means has caused the role of end-users to change from being a simple consumer to a producer of their *** new role has been called a prosumer and has contributed to modifying electricity markets,by allowing prosumers to merchandize the energy surplus to electricity companies and other *** fundamental key to any economic transaction is trust between the ***,new technologies,such as blockchain,are transforming transaction security,and allowing decentralization of the smart power *** study presents the development of a transactional model of electrical energy using the infrastructure of smart metering and blockchain systems to allow the commercialization of electrical energy by *** results show that for the Mexican electricity market,they can he good alternatives hy reducing subsidies and being more profitable than current rates.

关键词： Data visualization fault diagnosis IoT network photovoltaic system wireless remote monitoring

Optimized combinations of statins and azoles against Acanthamoeba trophozoites and cysts in vitro

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Asian Pacific Journal of Tropical Medicine 2019年第6期12卷 283-287页

作者： Ines Sifaoui Carmen M Martín-Navarro Atteneri López-Arencibia María reyes-Batlle Basilio Valladares joséE.Pinero Sutherland K Maciver Jacob Lorenzo-Morales University Institute of Tropical Diseases and Public Health of the Canary Islands University of La LagunaCanary IslandsSpain Centre for Integrative Physiology Biomedical SciencesEdinburgh Medical SchoolUniversity of EdinburghScotlandUK

Objective: To evaluate the combination of several statins(atorvastatin, fluvastatin and simvastatin) and azoles(voriconazole, posaconazole and itraconazole) against Acanthamoeba spp. Methods: The efficiency of the different drug combinations against the trophozoite stage of different Acanthamoeba strains were evaluated by Alamar Blue assay. Effect on the cyst stage was observed by inverted microscope. Cytotoxicity of combinations of azoles and statins was evaluated by measuring the release of lactate dehydrogenase from a murine macrophage cell line. Results: Combinations of any of the tested statins and voriconazole or posaconazole were more efficient in inhibiting Acanthamoeba compared to statins or azoles individually. The drug combinations at the combined inhibitory concentrations 50% showed lower toxicity compared to that of the compounds ***: The combinations of statins together with voriconazole and posaconazole are more efficient than these drugs alone, and these combinations have lower cytotoxicity in mammalian cell lines.

关键词： Keratitis Voriconazole Posaconazole Atorvastatin Fluvastatin Simvastatin

A novel motion tracking system for evaluation of functional rehabilitation of the upper limbs

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Neural Regeneration Research 2013年第19期8卷 1773-1782页

作者： ngel Gil-Agudo Ana de los reyes-Guzmán Iris Dimbwadyo-Terrer Benito Peasco-Martín Alberto Bernal-Sahún Patricia López-Monteagudo Antonio del Ama-Espinosa josé Luis Pons Department of Biomechanics and Technical Aids National Hospital for Spinal Cord Injury Health Department Indra SystemsAlcobendas Madrid Spain Bioengineering Group Spanish National Research Council (CSIC) Arganda del ReyMadrid Spain

Upper limb function impairment is one of the most common sequelae of central nervous system in jury, especially in stroke patients and when spinal cord injury produces tetraplegia. Conventional assessment methods cannot provide objective evaluation of patient performance and the effec tiveness of therapies. The most common assessment tools are based on rating scales, which are inefficient when measuring small changes and can yield subjective bias. In this study, we designed an inertial sensorbased monitoring system composed of five sensors to measure and analyze the complex movements of the upper limbs, which are common in activities of daily living. We devel oped a kinematic model with nine degrees of freedom to analyze upper limb and head movements in three dimensions. This system was then validated using a commercial optoelectronic system. These findings suggest that an inertial sensorbased motion tracking system can be used in patients who have upper limb impairment through data integration with a virtual realitybased neurorehabili tation system.

关键词： neural regenerationtion tracking upperroregenerationbrain injury spinal cordmb: neurorehabilitationnjury kinematic analysis inertial measurement mo-virtual reality sensors grants-supported paper neu-