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Spin Number Coherent States and the Problem of Two Coupled Oscillators

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Communications in Theoretical Physics 2015年第7期64卷 34-38页

作者： D.Ojeda-Guillén R.D.Mota V.D.Granados Escuela Superior de Fisica y Matemáticas Instituto Politécnico Nacional Ed. 9 Unidad Profesional Adolfo López Mateos Escuela Superior de Ingenieria Mecánica y Eléctrica Unidad Culhuacán Instituto Politécnico Nacional

From the definition of the standard Perelomov coherent states we introduce the Perelomov number coherent states for any su(2) Lie algebra. With the displacement operator we apply a similarity transformation to the su(2)generators and construct a new set of operators which also close the su(2) Lie algebra, being the Perelomov number coherent states the new basis for its unitary irreducible representation. We apply our results to obtain the energy spectrum, the eigenstates and the partition function of two coupled oscillators. We show that the eigenstates of two coupled oscillators are the SU(2) Perelomov number coherent states of the two-dimensional harmonic oscillator with an appropriate choice of the coherent state parameters.

关键词： coherent states Lie algebras coupled oscillators

Near shore seismic movements induced by seaquakes using the boundary element method

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 571-585页

作者： Alejandro Rodríguez-Castellanos Manuel Carbajal-Romero Norberto Flores-Guzmán J.Efraín Rodríguez-Sánchez Andriy Kryvko instituto mexicano del petróleo eje central lázaro cárdenas 152Gustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalupalmEdif.5Av.Instituto Politécnico Nacional S/NCol.LindavistaGustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalunidad profesional azcapotzalcoDistrito FederalMéxico centro de investigación en matemáticas jalisco s/nmineral de valencianaguanajuatoMéxico

This study quantifies seismic amplifications in near-shore arising from seaquakes. Within the Boundary Element Method, boundary elements are used to irradiate waves and force densities obtained for each element. Huygens′ Principle is implemented since the diffracted waves are constructed at the boundary from which they are radiated, which is equivalent to Somigliana′s theorem. Application of boundary conditions leads to a system of integral equations of the Fredholm type of second kind and zero order. Several numerical configurations are analyzed： The first is used to verify the present formulation with ideal sea floor configurations to estimate seismic amplifications. With the formulation verified, simple slope configurations are studied to estimate spectra of seismic motions. It is found that P-waves can produce seismic amplifications from 1.2 to 3.9 times the amplitude of the incident wave. SV-waves can generate seismic amplifications up to 4.5 times the incident wave. Another relevant finding is that the highest amplifications are at the shore compared to the ones at the sea floor.

关键词： seismic amplifications seaquake earthquake elastic waves boundary element method near shore cities

Growing arugula plants using aeroponic culture with an automated irrigation system

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International Journal of Agricultural and Biological Engineering 2020年第3期13卷 52-56页

作者： Jhon D.Ríos Salazar John E.Candelo-Becerra Fredy E.Hoyos Velasco Escuela de Física Facultad de CienciasUniversidad Nacional de ColombiaSede MedellínColombia Departamento de Energía Eléctrica y Automática Facultad de MinasUniversidad Nacional de ColombiaSede MedellínColombia

The paper presents an efficient form of growing arugula plants by means of automatic control of an aeroponic culture irrigation *** system considers a reprogrammable electronic circuit that uses software to generate different irrigation cycles to obtain an adequate growth of arugula *** show how different samples grown in a greenhouse had the same growth behavior as field-grown samples during the test *** was possible to obtain a more efficient and sustained five-week production to supply consumers by having a continuous cycle irrigation system,which was operated for 35 *** growth and number of leaves were maintained in a similar way for different plants *** grow similarly,but some of them showed size differences during the five weeks.

关键词： aeroponic culture arugula plants food production irrigation systems smart system

Power Grounding Optimization

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American Journal of Computational Mathematics 2015年第3期5卷 243-252页

作者： Eduardo A. Cano-Plata Oscar J. Soto-Marín Guillermo Jiménez-Lozano Jorge H. Estrada-Estrada Departamento de Ingenierí a Elé ctrica Electr&oacute nica y Computació n Universidad Nacional de Colombia Manizales Colombia

In this paper we discuss the finite element models (FEM) using electromagnetic theory—Maxwell’s equations. Next we developed a new procedure for optimization with the idea to be implemented in the standard IEEE-80 (... 详细信息

关键词： Finite Element Method Grounding Systems Circuit Model ETAP Model Engineering Design

Fuzzy Voice Coding with Significant Impulses Modeling and Redundant Waveform Recycling

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Communications and Network 2013年第1期5卷 50-56页

作者： Ismael Rosas Arriaga Juan C. García Infante J. Carlos Sánchez García Microelectronics Department Escuela Superior de Ingeniería Mecánica y Eléctrica Culhuacán Ciudad de México México

This paper proposes a voice codification based on two algorithms that make the wave form codification in time domain. The first uses the significant impulse model (SIM), which has as a goal to operate as an endpoint detector and as a dawn sampling, through the detection and selection of the significant valleys and crests;the second algorithm, is a redundant wave-form recycler (RWR) that uses an architecture based on fuzzy logic with an accumulative memory. The fuzzy algorithm obtains the similitude grade between the redundant wave forms, this with the objective of save into an knowledge base the patterns, based on the no supervised learning and when there are into memory, automatically there will be used to identified their arrive respect to the input signal, substituting the input block by the correspondent pattern into memory. This decoding process is using the SIM interpolation with a memory in accordance to the RWR.

关键词： Coding Signal Processing Fuzzy Logic Algorithms Pattern Recognition

Itinerary-Dependent Degradation Analysis of a Lithium-Ion Battery Cell for E-Bike Applications in Rwanda

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Energy Engineering 2024年第11期121卷 3121-3131页

作者： Aimable Ngendahayo AdriàJunyent-Ferré JoanMarc Rodriguez Bernuz Etienne Ntagwirumugara African Center of Excellence in Energy for Sustainable Development College of Science and TechnologyUniversity of RwandaKigaliP.O.Box 3900Rwanda Department of Electrical and Electronic Engineering Imperial College LondonLondonSW72BXUK Departament d’Enginyeria Elèctrica Universitat Politècnica de CatalunyaBarcelona08034Spain

There are obstacles to the widespread use of small electric vehicles(EVs)in Rwanda,including concerns regarding the battery range and ***-ion batteries(LIBs)play an important role in ***,their performance declines over time because of several *** optimize battery management systems and extend the range of EVs in Rwanda,it is essential to understand the influence of the driving profiles on lithium-ion battery *** study analyzed the degradation patterns of a lithium-ion battery cell that propels an E-bike using various real-world E-bike driving cycles that represent Rwandan driving conditions under deep discharge(>80%).By being aware of these variables,battery failure can be slowed and improved battery performance can be achieved to promote the transition to cleaner transportation in Rwanda for the productive use of *** analyzed parameters that affect battery performance are temperature,driving cycles,and state of *** was found that the higher the temperature,the higher was the rate of *** the other hand,the EVs that operate in the region with higher elevation(hilly region)combined with a flat surface where the riders use their physical forces to propel the E-bike and their batteries lose their capacity rapidly compared to those operating in regions where the energy from the lithium-ion battery assists for the entire *** draining the battery to 10%and charging it to 90%of its initial capacity,the capacity fading decreased by 5%.

关键词： Degradation driving cycle E-bike state of charge lithium manganese oxide

Erosion problem in tool steel using cold box core-making process

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China Foundry 2019年第3期16卷 204-210页

作者： Eduardo Rodríguez Alberto Pérez Rafael David Mercado-Solis Velasco-Téllez Abraham Omar Jimenez Martin Flores Marco Aurelio Gonzalez Jesus Ibarra Universidad de Guadalajara Departamento de Ingeniería de Proyectos/CUCEI CONACyT México Facultad de Ingeniería Mecánica y Eléctrica UANL México Nemak México S.A. García México Instituto Tecnológico José Mario Molina Pasquel y Henríquez Unidad Zapopan México

This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens were heat treated to obtain hardness of 294, 445 and 595 HV200 (29, 45 and 55 HRC). Erosion tests were carried out at impingement angles from 20° to 90° and air drag pressures of 1.38, 2.07 and 2.76 bar (20, 30 and 40 psi). The main results are summarized as follows:(i) The harder material, the lower erosion;(ii) the maximum erosion rate is at 30°;(iii) Little difference in erosion rate at impact angle of 60° and 90° for a constant pressure tested regardless of the hardness level;(iv) As the pressure increases, so does the erosion rate, being more sensitive for low impact angles. Finally, a differential form of the general erosion equation is applied on a practical core-making case to evaluate the erosion rate of the H13 steel at 30° and 90° impingement angles.

关键词： erosion cold box core-making H13 tool steel resin coated silica sand

Stabilization and control of unstable first order linear delay systems

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Stabilization and control of unstable first order linear del...

Fabrication of paper-based devices for in vitro tissue modeling

2008建模、辨识与控制国际会议

作者： B.del-Muro-Cuellar J.F.Mrquez-Rubio M.Velasco-Villa J.lvarez-Ramirez Hector Puebla Escuela Superior de Ingenieria Mecnica y Eléctrica Unidad Culhuacan Instituto Politécnico Nacional Universidad Autopnoma Metropolitana

This work considers the problem of stabilization and control of first order linear systems subject to input delay. As it is known, the stability analysis of this type of systems becomes difficult due to the term dead time considered. To solve the stabilization problem as a first step are presented the conditions that assures the stability of the systems in closed loop with a proportional feedback, these condition are derived with a novel methodology based on a discrete time approach. The stability conditions are used to design an observer (predicting) scheme that provides adequate convergent error. The proposed scheme results similar to the traditional Smith Predictor that can be used on the case of stable systems. The observer scheme is complemented by the use of a PI compensator to follows step reference signals.

关键词： Time delay, stabilization, Smith predictor

来源： cnki会议评论

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Bio-Design and Manufacturing 2020年第3期3卷 252-265页

作者： Hongbin Li Feng Cheng Juan A.Robledo-Lara Junlong Liao Zixuan Wang Yu Shrike Zhang Division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolCambridgeMA 02139USA College of Light Industry and Textile Qiqihar UniversityQiqihar 161000HeilongjiangPeople’s Republic of China Departamento de Ingeniería Mecatrónica y Eléctrica Escuela de Ingeniería y CienciasTecnológico de MonterreyCP 78211 San Luis PotosíSan Luis PotosíMexico

Paper devices have recently attracted considerable attention as a class of cost-effective cell culture substrates for various biomedical *** paper biomaterial can be used to partially mimic the in vivo cell microenvironments mainly due to its natural three-dimensional *** paper-based devices provide precise control over their structures as well as cell distributions,allowing recapitulation of certain interactions between the cells and the extracellular *** features have shown great potential for the development of normal and diseased human tissue *** this review,we discuss the fabrication of paper-based devices for in vitro tissue modeling,as well as the applications of these devices toward drug screening and personalized *** is believed that paper as a biomaterial will play an essential role in the field of tissue model engineering due to its unique performances,such as good biocompatibility,eco-friendliness,cost-effectiveness,and amenability to various biodesign and manufacturing needs.

关键词： Paper-based devices In vitro Tissue modeling Disease modeling Drug screening Personalized medicine