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This work proposes a design methodology for predictive control applied to the single-phase PWM inverter with an LC filter. In the design, we considered that the PWM inverter has parametric uncertainties in the filter inductance and output load resistance. The control system purpose is to track a sinusoidal signal at the inverter output. The designed control system with an embedded integrator uses the principle of receding horizon control, which underpinned predictive control. The methodology was described by linear matrix inequalities, which can be solved efficiently using convex programming techniques, and the optimal solution is obtained. MATLAB-Simulink and real-time FPGA-in-the-loop simulations illustrate the viability of the proposed control system. The LMI-based MPC reveals an effective performance for tracking of a sinusoidal reference signal and disturbance rejection of input voltage and load perturbations for the inverter subject to uncertainties.

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This paper presents novel current sensorless maximum-power point-tracking (MPPT) algorithms based on compensators/controllers and a single-input voltage sensor. The proposed MPPTs eliminate the expensive and noisy current sensor, which can significantly reduce the system cost and retain the advantages of the widely used MPPT algorithms, such as Incremental Conductance (IC) and Perturb and Observe (P&O) algorithms. Additionally, it is verified that the proposed algorithms, especially the proposed Current Sensorless V based on PI, can reach outstanding tracking factors (TFs) such as the IC and P&O based on PI algorithms. In this sense, the insertion of controllers inside the MPPT gives them adaptive characteristics, and the experimental TFs are in the remarkable range of more than 99%, with an average yield of 99.51% and a peak of 99.80%.

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This paper aims to present the analysis and development of a complete electronic smart meter that is able to perform four-quadrant measurements, act as a three-phase shunt active power filter (APF), and control three-phase induction motors by stator flux estimation. A transmission control protocol together with Internet protocol (TCP/IP) communication protocol for the remote access of measurement data is embedded into the application to securely transmit reliable information. An artificial neural network trained with particle swarm optimization is used for stator flux estimation, and a fuzzy logic controller is adopted to regulate the power converter DC bus voltage. The present work gathers knowledge from multidisciplinary fields, and all applied techniques have not been proposed altogether before. All control functions are embedded into a field-programmable gate array (FPGA) device, using VHSIC Hardware Description Language (VHDL), to enhance efficiency taking advantage of parallelism and high speed. An FPGA-in-the-loop cosimulation technique was first applied to prove the control functions' functionality, and, later, experimental evaluations are conducted to finally prove equipment operation and reliability.

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Mapping utility poles using side-view images acquired with car-mounted cameras is a time-consuming task, mainly in larger areas due to the need for street-by-street surveying. Aerial images cover larger areas and can be feasible alternatives although the detection and mapping of the utility poles in urban environments using top-view images is challenging. Thus, we propose the use of Adaptive Training Sample Selection (ATSS) for detecting utility poles in urban areas since it is a novel method and has not yet investigated in remote sensing applications. Here, we compared ATSS with Faster Region-based Convolutional Neural Networks (Faster R-CNN) and Focal Loss for Dense Object Detection (RetinaNet ), currently used in remote sensing applications, to assess the performance of the proposed methodology. We used 99,473 patches of 256 × 256 pixels with ground sample distance (GSD) of 10 cm. The patches were divided into training, validation and test datasets in approximate proportions of 60%, 20% and 20%, respectively. As the utility pole labels are point coordinates and the object detection methods require a bounding box, we assessed the influence of the bounding box size on the ATSS method by varying the dimensions from 30×30 to 70×70 pixels. For the proposal task, our findings show that ATSS is, on average, 5% more accurate than Faster R-CNN and RetinaNet. For a bounding box size of 40×40, we achieved Average Precision with intersection over union of 50% (AP50) of 0.913 for ATSS, 0.875 for Faster R-CNN and 0.874 for RetinaNet. Regarding the influence of the bounding box size on ATSS, our results indicate that the AP50 is about 6.5% higher for 60×60 compared to 30×30. For AP75, this margin reaches 23.1% in favor of the 60×60 bounding box size. In terms of computational costs, all the methods tested remain at the same level, with an average processing time around of 0.048 s per patch. Our findings show that ATSS outperforms other methodologies and is suitable for developing operation tools that can automatically detect and map utility poles.

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OBJECTIVE: This study aimed to explore the functional connectivity of the default mode network (DMN) in crack-cocaine users, in comparison with that observed in age-matched non-drug-using controls. MATERIALS AND METHODS: Inpatient crack-cocaine users who had been abstinent for at least four weeks and age-matched non-drug-using controls underwent resting state functional magnetic resonance imaging. Images were acquired while the subjects rested with their eyes closed. After data preprocessing, DMNs were defined by spatial independent component analysis and seed-based correlation analysis, by chosen regions of interest centered in the ventral anterior cingulate cortex and in the posterior cingulate cortex. RESULTS: The functional connectivity of the DMN determined by independent component analysis did not differ between the crack-cocaine users and the controls. However, the seed-based correlation analysis seeking a single metric of functional connectivity between specific brain regions showed that the negative connectivity between the ventral anterior cingulate cortex and the left superior parietal lobule was significantly greater in the crack-cocaine users than in the controls. CONCLUSION: The results suggest that selective extrinsic network connectivity of the DMN related to motor and executive function is impaired during crack-cocaine addiction.

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Abstract Objective: This study aimed to explore the functional connectivity of the default mode network (DMN) in crack-cocaine users, in comparison with that observed in age-matched non-drug-using controls. Materials and Methods: Inpatient crack-cocaine users who had been abstinent for at least four weeks and age-matched non-drug-using controls underwent resting state functional magnetic resonance imaging. Images were acquired while the subjects rested with their eyes closed. After data preprocessing, DMNs were defined by spatial independent component analysis and seed-based correlation analysis, by chosen regions of interest centered in the ventral anterior cingulate cortex and in the posterior cingulate cortex. Results: The functional connectivity of the DMN determined by independent component analysis did not differ between the crack-cocaine users and the controls. However, the seed-based correlation analysis seeking a single metric of functional connectivity between specific brain regions showed that the negative connectivity between the ventral anterior cingulate cortex and the left superior parietal lobule was significantly greater in the crack-cocaine users than in the controls. Conclusion: The results suggest that selective extrinsic network connectivity of the DMN related to motor and executive function is impaired during crack-cocaine addiction.

Resumo Objetivo: Este estudo teve como objetivo explorar a conectividade funcional da rede de modo padrão em usuários de crack-cocaína comparando-a a controles não usuários da mesma faixa etária. Materiais e Métodos: Usuários de crack-cocaína internados em abstinência por pelo menos quatro semanas e controles não usuários pareados por idade foram submetidos a ressonância magnética funcional em estado de repouso, enquanto descansavam com os olhos fechados. Depois do pré-processamento de dados, a rede de modo padrão foi definida por análise espacial de componentes independentes e análise de correlação baseada em sementes, por regiões de interesse centradas no córtex cingulado anterior ventral e no córtex cingulado posterior. Resultados: A conectividade funcional analisada por componentes independentes não foi diferente entre os usuários de crack- cocaína e os controles pareados por idade. No entanto, a análise de correlação baseada em sementes à procura de uma conectividade funcional métrica única entre regiões específicas do cérebro mostrou uma negatividade significativamente maior da conectividade entre o córtex cingulado anterior ventral e o lóbulo parietal superior esquerdo, quando comparada a controles pareados por idade. Conclusão: Os resultados sugerem que conectividades extrínsecas seletivas da rede de modo padrão relacionadas a funções motoras e executivas podem estar comprometidas na dependência de crack-cocaína.

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Here, we report some electrophysiologic and imaging effects of the transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (dlPFC) in drug addiction, notably in alcohol and crack-cocaine dependence. The low resolution electromagnetic tomography (LORETA) analysis obtained through event-related potentials (ERPs) under drug-related cues, more specifically in its P3 segment (300-500 ms) in both, alcoholics and crack-cocaine users, showed that the ventral medial prefrontal cortex (vmPFC) was the brain area with the largest change towards increasing activation under drug-related cues in those subjects that kept abstinence during and after the treatment with bilateral tDCS (2 mA, 35 cm(2), cathodal left and anodal right) over dlPFC, applied repetitively (five daily sessions). In an additional study in crack-cocaine, which showed craving decreases after repetitive bilateral tDCS, we examined data originating from diffusion tensor imaging (DTI), and we found increased DTI parameters in the left connection between vmPFC and nucleus accumbens (NAcc), such as the number of voxels, fractional anisotropy (FA) and apparent diffusion coefficient (ADC), in tDCS-treated crack-cocaine users when compared to the sham-tDCS group. This increasing of DTI parameters was significantly correlated with craving decreasing after the repetitive tDCS. The vmPFC relates to the control of drug seeking, possibly by extinguishing this behavior. In our studies, the bilateral dlPFC tDCS reduced relapses and craving to the drug use, and increased the vmPFC activation under drug cues, which may be of a great importance in the control of drug use in drug addiction.

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Uma revisäo de literatura foi realizada para atualizaçäo dos múltiplos aspectos envolvidos na etiopatogenia da lesäo aguda da mucosa gástrica. As pesquisas apontam que o determinante fundamental para o desenvolvimento da lesäo aguda da mucosa gástrica é o acúmulo de íon hidrogênio na lâmina própria da mucosa, em funçäo de duas situaçöes: (a) decorrente do aumento significativo na velocidade de retrodifusäo, o que acontece na vigência de quebra de barreira da mucosa: (b) quando o íon hidrogênio, que normalmente se difunde para o interstício, é impossibilitado de ser carreado pelo fluxo sangüíneo, o que acontece em vigência do estado de má perfusäo gástrica

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Os autores analisam 27 pacientes operados no Hospital dos Plantadores de Cana, com o diagnostico de cancer colorretal, no periodo compreendido entre junho de 1975 e dezembro de 1980. O grupo era composto por 16 pacientes do sexo feminino (59,3 por cento) e 11 do sexo masculino (40,7 por cento). O individuo mais jovem tinha 29 anos e o mais idoso 87, com a media de idades de 55,3 anos. Os tumores estavam distribuidos pelos colons da seguinte maneira: 12 ao nivel do reto (44,45 por cento), sete localizados no segmoide (25,9 por cento), tres no colon esquerdo (11,1 por cento) e cinco no colon direito (18,5 por cento), Em dois pacientes havia tumores sincronicos de colon direito e sigmoide. Usando os criterios de Dukes, os tumores foram assim classificados: Tipo A-2, tipo B-8, tipo C-9 e tipo D-8. Histologicamente 25 pacientes eram portadores de adenocarcinomas e dois apresentavam tumores epidermoides. Em 23 pacientes foram realizadas cirurgias de ressecçao do tubo digestivo incluindo a massa neoplasica. em tres doentes as cirurgias visaram unicamente evitar a obstruçao do tubo gastrointestinal. Em um paciente foi praticada excisao local. Desses pacientes tres faleceram no pos-operatorio imediato, perfazendo um indice de mortalidade de 11,1 por cento, 11 vieram a falecer posteriormente a alta hospitalar, com o minimo de sobrevida de 40 dias e o maximo de 2 anos. Em 01-06-82 13 pacientes (48,1 por cento) estavam vivos, com sobrevida superior a um ano da cirurgia, quatro estao vivos decorridos mais de quatro anos da cirurgia e um apresenta sobrevida superior a cinco anos

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