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This chapter describe the operation points, i.e., the necessary parameters to excited the surface plasmon for the free electron type metals. Aspects like incident angle range, wavelength range, metal thickness, optical substrate,... more
This chapter describe the operation points, i.e., the necessary parameters to excited the surface plasmon for the free electron type metals. Aspects like incident angle range, wavelength range, metal thickness, optical substrate, nanoparticle size, dynamic range, responsivity, SPR depth intensity and line broadening are present.
This paper presents a control for universal active filters derived from the current-shaping control strategy previously employed for shunt active filters. It operates with a reduced number of sensors, using only two AC and one DC real... more
This paper presents a control for universal active filters derived from the current-shaping control strategy previously employed for shunt active filters. It operates with a reduced number of sensors, using only two AC and one DC real time measurements. The proposed solution has natural mitigation capability for nonlinear loads, which can be further improved with a quasi-resonant scheme. The resulting nonlinear energy flow tracking is designed using a robust control framework, with guaranteed stability and optimal performance for a predefined range of operation. Experimental results are presented using a 1kVA prototype.
Ventricular assist devices are mechanical blood pumps used to provide circulatory support in patients waiting for a heart transplantation. In many cases, when the support lasts for months it may be advantageous to use a pump with a... more
Ventricular assist devices are mechanical blood pumps used to provide circulatory support in patients waiting for a heart transplantation. In many cases, when the support lasts for months it may be advantageous to use a pump with a physiological control system to automatically adjust pump output in response to changes in the cardiovascular system (CVS). In this paper, we present a physiological controller for a pulsatile ventricular assist device (PVAD) that controls the device ejection volume considering the heart beat frequency. A mathematical model of the CVS based on analog electric circuits is used to analyze the cardiovascular response under ventricular assistance. The physiological controller is shown to be able to improve simulated hemodynamic conditions.
This chapter describes the operation points, i.e., the necessary parameters to excite the surface plasmon for the free-electron type metals (Al, Li, and Mg). Aspects like incident angle range, wavelength range, metal thickness, optical... more
This chapter describes the operation points, i.e., the necessary parameters to excite the surface plasmon for the free-electron type metals (Al, Li, and Mg). Aspects like incident angle range, wavelength range, metal thickness, optical substrate, nanoparticle size, dynamic range, responsivity, SPR depth, intensity and line broadening are present.
This chapter describes the operation points, i.e., the necessary parameters to excite the surface plasmon for the classical noble metals (Cu, Au, and Ag). Aspects like incident angle range, wavelength range, metal thickness, optical... more
This chapter describes the operation points, i.e., the necessary parameters to excite the surface plasmon for the classical noble metals (Cu, Au, and Ag). Aspects like incident angle range, wavelength range, metal thickness, optical substrate, nanoparticle size, dynamic range, responsivity, SPR depth, intensity and line broadening are present.
Metal-Insulator multilayer structures (Ag-Al2O3-Ag) that exhibit a manifold of internal interfaces are artificial materials, and also known as meta-materials. Their optical SPR properties are experimentally yet not explored.
This paper proposes a four-port AC/DC-DC/AC converter composed of a half-bridge converter and a full-bridge converter replacing their inductive filters by means of a transformer. The power balance between the ports is achieved through... more
This paper proposes a four-port AC/DC-DC/AC converter composed of a half-bridge converter and a full-bridge converter replacing their inductive filters by means of a transformer. The power balance between the ports is achieved through both duty-cycles and the phase angle between the voltages applied by these bridges. The analysis of the converter was accomplished by using the superposition principle allowing to define different modes of operation. Furthermore, a control strategy is proposed for an application of the converter and in order to corroborate the theoretical analysis, simulation and experimental results are introduced. Finally, the performance of the converter is assessed as a function of the delivered power.
Micromachined flow sensors have appropriate features that allow the use for microfluidic systems in biosensors. Among these flow sensors, those based on the principle of thermal transfer are the most recently investigated. Here, a... more
Micromachined flow sensors have appropriate features that allow the use for microfluidic systems in biosensors. Among these flow sensors, those based on the principle of thermal transfer are the most recently investigated. Here, a miniaturized sensor, which is based on the thermal anemometry, has been used to measure the flow velocity produced by a roller-based peristaltic mini-pump. The detection element consists of a heating element and a temperature monitoring element. Temperature compensation is achieved, and the instantaneous flow velocity is obtained from the sensor output voltage measurement. The sensor has been characterized and positioned in the normal direction to the flow. Eventually, the characteristic curve has been evaluated to provide an adequate control mechanism.
This paper presents an in silico study on the use of graphene and molybdenum disulfide to increase sensor sensitivity. A multilayer structure in the Kretschmann configuration whose optically coupled substrate is a polymeric trapezoidal... more
This paper presents an in silico study on the use of graphene and molybdenum disulfide to increase sensor sensitivity. A multilayer structure in the Kretschmann configuration whose optically coupled substrate is a polymeric trapezoidal prism is used in angular interrogation mode to detect changes in the order of 0.002 in the analyte layer. The graphene monolayers deposition above the metallic film results in a significant increase in the sensitivity, reaching 8452.11 nm/RIU. However, despite being widely used to improve sensor responsiveness in some SPR sensor models, the addition of the molybdenum disulfide layer reduces the improvement resulting from the insertion of the graphene layers.
This paper presents a single-phase four-leg ac-dc-ac converter, with one leg shared by the grid side and the load side. The proposed topology can generate input and output voltages with seven levels, presenting reduced harmonic... more
This paper presents a single-phase four-leg ac-dc-ac converter, with one leg shared by the grid side and the load side. The proposed topology can generate input and output voltages with seven levels, presenting reduced harmonic distortion, in addition to using reduced voltage switches. The space-vector pulsewidth modulation strategy (SV-PWM), the control technique, the system model, and a comparison with a three-leg topology will be presented. As for performance comparison parameters, harmonic distortion in currents and voltages, the average switching frequency, and semiconductor losses will be used. The topology was simulated and assembled in the laboratory to obtain experimental results.
This paper presents some improvements over the previously presented current-shaping control for parallel active filters. The proposed strategy allows the active filter to operate with a reduced number of sensors, and dependently of phase... more
This paper presents some improvements over the previously presented current-shaping control for parallel active filters. The proposed strategy allows the active filter to operate with a reduced number of sensors, and dependently of phase synchronization schemes for references generation. A new realization proposal employs a quasi-resonant system frequency adaptable to implement complex impedances, and have low interaction with harmonic components in the grid. An additional quasi-resonant scheme in a stationary reference frame is proposed to extend the current shaping control in order to achieve great mitigation capability. The energy flow control in this paper deals with further uncertainties, which results in an enhanced robust design methodology. Experimental results are presented using a 1kVA prototype.
This paper presents a nine-leg (9L) multilevel inverter to drive a six-phase induction machine in an open-end winding (OEW) configuration. The system is based on three conventional two-level three-phase voltage source inverters (VSIs) and... more
This paper presents a nine-leg (9L) multilevel inverter to drive a six-phase induction machine in an open-end winding (OEW) configuration. The system is based on three conventional two-level three-phase voltage source inverters (VSIs) and three, two, or one isolated dc links. A machine with two sets of 30 degrees shifted three-phase stator windings is considered. The inverter operating principles are discussed and a simple space-vector pulse-width modulation (SV-PWM) is proposed. The 9L-OEW system is compared with two conventional drives: the six-leg two-level (6L), and the 12-leg OEW (12L-OEW) systems. The number of components, the required dc-link voltage, voltage and current harmonic distortions, torque ripple, and semiconductor losses are considered as figures of merit. Simulations and experiments were also performed, showing steady-state results for a 1 HP machine operating at constant torque.
A numerical simulation tool is reported for nanometer thin and inhomogeneous immobilized protein films on gold in aqueous solution. It allows for the first time, to the best of our knowledge, the simultaneous assessment of refractive... more
A numerical simulation tool is reported for nanometer thin and inhomogeneous immobilized protein films on gold in aqueous solution. It allows for the first time, to the best of our knowledge, the simultaneous assessment of refractive index, film thickness, and surface coverage. The model relies on and combines the convective diffusion equation, the Langmuir adsorption isotherm, and the Helmholtz equation, with appropriate boundary conditions. These three differential equations were jointly solved using a multiphysics software. The physical film parameters were extracted employing an optimization procedure for immobilized bovine serum albumin, hemoglobin, and neutravidin films. The relatively good agreement between the extracted values for the refractive index, film thickness, and surface coverage and the corresponding values reported in the open literature show the correctness of the proposed methodology.
The two sensing modes under consideration, the angular (AIM) and spectral (WIM) modes, exhibit advantages and disadvantages in terms of technical complexity, data processing and operating conditions. Schematics of the AIM and WIM optical... more
The two sensing modes under consideration, the angular (AIM) and spectral (WIM) modes, exhibit advantages and disadvantages in terms of technical complexity, data processing and operating conditions. Schematics of the AIM and WIM optical set-up are shown in Fig. 3.1a, b, respectively. Each setup comprises a flat dove type prism chip. The design route allows the construction of compact instruments and avoids implementation of a bulky optical prism. The optical function of SPR prism chip is similar to a waveguide. In the AIM, incident radiation is a spectrally narrow band, while the angle range is wide and the resonance angle is recorded. In the WIM, the incident radiation is spectrally broadband, the incident angle range is narrow, comprising a collimated light beam, and a spectrometer tracks the resonance wavelength. A third-less popular-hybrid sensor configuration is the Intensity Mode (IM), as shown in Fig. 3.1c, where a collimated beam at a fixed (resonance) angle and wavelength is employed. The temperature coefficient of the refractive index of water at ambient T, with \(-1.2\times 10^{-4}\) RIU/\({^\circ }\)C, is quite high and exceeds those of the optical components, typically used in the optics design. Hence, it should be recalled that SPR sensors are particularly sensitive to temperature fluctuations. They are also sensitive to mechanical vibrations or thermal distortions in the optical path, down to the micrometer or even sub-micrometer levels. A rigid mechanical design is therefore beneficial. Surface conditions, preparation and functionalization, as well as long term temporal stability and signal drift effects are further important issues, since recordings may last for several hours.
This chapter describes the operation points, i.e., the necessary parameters to excite the surface plasmon for other common metals (In, Sn, Zn, Pb, and Bi). Aspects like incident angle range, wavelength range, metal thickness, optical... more
This chapter describes the operation points, i.e., the necessary parameters to excite the surface plasmon for other common metals (In, Sn, Zn, Pb, and Bi). Aspects like incident angle range, wavelength range, metal thickness, optical substrate, nanoparticle size, dynamic range, responsivity, SPR depth, intensity and line broadening are present.
This chapter describes the operation points, i.e., the necessary parameters to excite the surface plasmon for active metal-type compounds (ITO and TiN). Aspects like incident angle range, wavelength range, metal thickness, optical... more
This chapter describes the operation points, i.e., the necessary parameters to excite the surface plasmon for active metal-type compounds (ITO and TiN). Aspects like incident angle range, wavelength range, metal thickness, optical substrate, nanoparticle size, dynamic range, responsivity, SPR depth, intensity and line broadening are present.
Page 1. Studies of power electronics using formal methods Márcia Verônica Costa Miranda 1 , Antônio Marcus Nogueira Lima 2 1 Fundamental and Social Science Departament, CCA, UFPB, Paraiba, Brazil, e-mail : miranda ...
Stereotypic behaviours are present in both human and nonhuman primates. Usually, these behaviours are a welfare indicator. However, the stereotypic behaviours may be also a symptom of some mental disorder in the humans. A specific case is... more
Stereotypic behaviours are present in both human and nonhuman primates. Usually, these behaviours are a welfare indicator. However, the stereotypic behaviours may be also a symptom of some mental disorder in the humans. A specific case is Autism Spectrum Disorder (ASD). The individuals with ASD may exhibit stereotypic behaviours through some gestures. The classic stereotyped gestures of autism are: (i) Body Rocking; (ii) Hand Flapping; and (iii) Top Spinning. This paper study the performance between two machine learning algorithms to recognition the stereotyped gestures typical of autism: (i) Hidden Markov Model [HMM]; and (ii) Support Vector Machine [SVM]. Sequence of orientations data from some joints obtained through a RGB-D (Red Green Blue - Depth) camera [Kinect®] are used for analysis. The results of these two machine learning algorithms are compared with state-of-the-art. The HMM approach proposed in this paper have shown 98.89% average recognition rate and 98.9% recall. This value is higher compared to the SVM approach and the others of art method presented.
The characterization of a surface plasmon resonance sensor operating in the grating mode has been explored theoretically and experimentally. Wavelength interrogation mode was exploited at specular reflection in the gas phase for thin gold... more
The characterization of a surface plasmon resonance sensor operating in the grating mode has been explored theoretically and experimentally. Wavelength interrogation mode was exploited at specular reflection in the gas phase for thin gold films, deposited onto a corrugated polymer substrate by sputtering. Some tests using water vapor were performed and the achievable responsivity at specular reflection was determined experimentally to be 87 nm/RIU and the limit of detection of 13.2×10−3 RIU was calculated. The good agreement between experimental and theoretical results confirms the correctness of the methodology and the feasibility of the proposed sensing system.
This work presents a theoretical and experimental results obtained with surface resonance sensors operating in the periodic grating mode. The spatial periodicity of the corrugated surface of the manufactured devices was set to 478 nm. Two... more
This work presents a theoretical and experimental results obtained with surface resonance sensors operating in the periodic grating mode. The spatial periodicity of the corrugated surface of the manufactured devices was set to 478 nm. Two types of metallic layers have been tested, one of 50 nm of gold and another of 100 nm of copper. The wavelength interrogation mode has been used and the beam of incident light was shined directly onto the metal layer. The characteristics of the transducer manufactured with the two corrugated surfaces have been explored in the Kretschmann configuration to determine the sensors responsivities. The obtained results confirmed the correctness of the proposed methodology and the feasibility of the proposed transducer designs. The sensor system was tested for situations where a change in the refractive index of the gas occurs due to the insertion of condensed water vapor. Both transducers are tested and results as sensibility and detection limit are presented and compared.
Battery mathematical models can be employed to predict its behavior under various charging and discharging conditions, and in some applications, they are key elements for the successes of the design. In this paper, it is analyzed a... more
Battery mathematical models can be employed to predict its behavior under various charging and discharging conditions, and in some applications, they are key elements for the successes of the design. In this paper, it is analyzed a lead-acid battery model for voltage and lifetime estimation. The chosen model synthesis is based on an electrical equivalent circuit, and has the features that allow it to be used in the calculation of the remaining capacity. The lifetime model employs an adaptive update mechanism during the simulation such that the battery performance is reduced depending on the operating conditions. This paper objective is to generalize the analyzed mathematical system to be used in any lead-acid battery. Both the model and the estimation algorithm are evaluated with two batteries with same voltage and nominal capacity. The generalization of equation is made by the addition of three new parameters to minimize an objective function based on the least squares error. The study is based on a specific scenario that makes the battery reached the end of its lifetime. With the addition of new parameters, the RMS error between real capacity and calculated capacity are evaluated.
... Gutemberg GS Junior, Mateus AM Lima, Walter 0. G. Filho, Angelo Perkusich, Member, IEEE Marcos RA Morais, and Antonio Marcus N. Lima, Senior Member, IEEE Abstract--Huffman coding is an efficient coding technique that is largely used... more
... Gutemberg GS Junior, Mateus AM Lima, Walter 0. G. Filho, Angelo Perkusich, Member, IEEE Marcos RA Morais, and Antonio Marcus N. Lima, Senior Member, IEEE Abstract--Huffman coding is an efficient coding technique that is largely used in applications that need a lossless ...
Control of wheeled mobile robots (WMRs) on trajectory tracking problems has given rise to an abundant proposals at recent years. Normally, WMRs are subject to phenomena like sliding, deformability or flexibility, which are strongly... more
Control of wheeled mobile robots (WMRs) on trajectory tracking problems has given rise to an abundant proposals at recent years. Normally, WMRs are subject to phenomena like sliding, deformability or flexibility, which are strongly associated with violation of velocity constraints. Here, we propose a method to reduce the effects of slipping and skidding in WMRs by using an auxiliary control law whose robustness is based on slipping and skidding variations. It is considered the control law based on state-feedback linearization whose robustness with respect to the deformability of wheel will be based on singular perturbation methods. The tracking problem is studied by using the auxiliary control law proposed in a feedforward loop. The results show that the law proposed is robust to slipping and skidding and that tracking error converges toward zero.
In this paper batteries' models and state of charge monitoring procedures are evaluated. Modeling of batteries are intended to assist designing of power electronics devices, while monitoring procedures are intended for a more... more
In this paper batteries' models and state of charge monitoring procedures are evaluated. Modeling of batteries are intended to assist designing of power electronics devices, while monitoring procedures are intended for a more effective State Of Charge (SOC) computing. It is worth noting that this still a hard task when working with lead acid batteries. Two models and three procedures
This paper presents a reduced switch count AC drive system using the single-phase to three-phase four-leg converter. The configuration was conceived to operate with a three-phase machine. A control strategy is proposed to obtain the same... more
This paper presents a reduced switch count AC drive system using the single-phase to three-phase four-leg converter. The configuration was conceived to operate with a three-phase machine. A control strategy is proposed to obtain the same voltage rating of the five-leg converter. The system can be used for applications in which the machine operates with frequency and amplitude constants at high speed and with amplitude and frequency variables at low speed. Simulation and experimental results are presented
... 1: 244-248 [6] Melendez J., Carr R., Bartholomew DU, Kukanskis K., Elkind J., Yee S., Furlong C., Woodbury R. (1996) A commercial solution for surface plasmon sensing; Sens. Actuators B35: 212-216 [7] Neff H., Zong W., Lima AMN, Borre... more
... 1: 244-248 [6] Melendez J., Carr R., Bartholomew DU, Kukanskis K., Elkind J., Yee S., Furlong C., Woodbury R. (1996) A commercial solution for surface plasmon sensing; Sens. Actuators B35: 212-216 [7] Neff H., Zong W., Lima AMN, Borre M., Holzhueter G., (2006) Optical ...
ABSTRACT
This paper studies analytically and quantitatively the influence of the power source on the dynamic performance of the altitude control system of a quadrotor powered by an electrochemical battery. This paper also proposes the formulation... more
This paper studies analytically and quantitatively the influence of the power source on the dynamic performance of the altitude control system of a quadrotor powered by an electrochemical battery. This paper also proposes the formulation of the altitude as a constrained optimization problem in which the drone, actuators, control law, and electrochemical battery models are considered, to define a trade-off between the power consumption rate and the closed-loop dynamic performance loss. An analytical representation of the effect of the battery discharge over the altitude dynamics is obtained through a linear approximation, enabling an analysis of the system poles. The problem of designing an altitude controller is then posed as a constrained optimization problem that can include the battery as a factor. A comparison of the error dynamics between the cases of the battery-unaware controller design and the battery-aware controller design is performed in simulations and experimental fligh...
The power balance and conditions of co-existing radiative and non-radiative surface plasmon resonance modes have been exploited at the metal film-water interface. Angular (AIM) and wavelength (WIM) interrogation sensing conditions were... more
The power balance and conditions of co-existing radiative and non-radiative surface plasmon resonance modes have been exploited at the metal film-water interface. Angular (AIM) and wavelength (WIM) interrogation sensing conditions were applied. Polycrystalline, void-free metal layers were sputter deposited, composed of nm-sized crystalline grains. Radiative decay of propagating SPs, with emission into the upper half-space, has been observed for 50-nm thin Au and Ag-layers on BK7 glass and polymeric substrates in the AIM. The associated thermo-optical power budget has been quantified by calorimetric heat flow recordings, comprising a micro-fluidic set-up. For the Au-water interface, at least 88 ± 4 % of the SP-absorbed optical power dissipates by phonon excitation, followed by heat transfer from the metal film into the adjacent liquid phase. Only a small fraction of 2.4 ± 0.6 % dissipates through radiative emission. In presence of a rough interface and WIM conditions, radiative SP-decay persists by emission into the lower half-space. The luminescence type feature most likely originates from radiative excitation and decay of localized SPs, coupled to propagating SPs within the film volume. The spectral characteristic is in accord with earlier reported experimental observations by others and numerical simulations.
Page 1. Four Leg Voltage Source Converter Based Dynamic Voltage Restorer BAPriyanka and K.Vijayakumar Electrical and Electronics Department, SRM University, Kattankulathur, Kancheepuram District, Tamil Nadu-601302 ...
Research Interests:
This paper presents trajectory controllers for differentialdrive, wheeled mobile robots. Three control strategies based on output feedback are presented: a proportional, a non-linear and a fuzzy controller. The control design relies on... more
This paper presents trajectory controllers for differentialdrive, wheeled mobile robots. Three control strategies based on output feedback are presented: a proportional, a non-linear and a fuzzy controller. The control design relies on the kinematic model of differential-drive robots. Since dynamic model changes with robot payload, dynamic controllers are not treated. Indeed, effets due to robot dynamics are considered as disturbance and shall be corrected by the controller. Two independent velocity controllers based on the model reference strategy are employed and the wheels reference velocities are provided by the trajectory controller. Simulations illustrate the performance and limitations of each controller considering a robot model including robot dynamics, actuators saturation and noise in the trajectory error variables.
ABSTRACT In this article a visual feedback control system implementation is presented. The proposed system integrates a trajectory planning method into the controller of a five-degree-of-freedom manipulator aiming to simplify object... more
ABSTRACT In this article a visual feedback control system implementation is presented. The proposed system integrates a trajectory planning method into the controller of a five-degree-of-freedom manipulator aiming to simplify object handling and obstacle avoidance. The system aims the intelligent handling of several parts, generating obstacle free paths whenever possible. The workspace information is provided by a redundant vision system: a RGB camera placed over the handler actuator and a fixed RGB-D camera.
ABSTRACT A calorimetric flow meter have been proposed here, where a finite element-based software is used to model and design it. Some parameters have been investigated and the results are also shown. Finally, an experimental setup has... more
ABSTRACT A calorimetric flow meter have been proposed here, where a finite element-based software is used to model and design it. Some parameters have been investigated and the results are also shown. Finally, an experimental setup has been presented to check the theoretical design.
ABSTRACT This paper presents a surface plasmon resonance system based on a polymer prism chip. The device allows operation in both the angular and wavelength interrogation modes. The biochip design is discussed emphasizing the effect of... more
ABSTRACT This paper presents a surface plasmon resonance system based on a polymer prism chip. The device allows operation in both the angular and wavelength interrogation modes. The biochip design is discussed emphasizing the effect of the ambient temperature over the optical behavior. Birefringence effect, biochip polishing, and responsivity are also reported. The basic mathematical formulation for both operating modes is discussed, and morphological parameters are considered in the data analysis. Experimental sensorgrams obtained at both interrogation modes with the same polymer prism chip are presented and compared. The experimental sensorgrams obtained with assays providing reversible (phosphate buffered saline and hypochlorite solutions) and irreversible (neutravindin solution) bindings demonstrate the feasibility of the proposed design.
Abstract: This paper presents a novel methodology for the trajectory tracking control of nonholonomic wheeled mobile robots using multiple identification models. The overall control system includes two stages. In the first stage, a... more
Abstract: This paper presents a novel methodology for the trajectory tracking control of nonholonomic wheeled mobile robots using multiple identification models. The overall control system includes two stages. In the first stage, a kinematic controller developed by ...

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