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Este artículo desarrolla procedimientos de diseño de Servosistemas tipo Proporcional Integral (SS abreviado) para controlar una planta no lineal de doble propósito: el Péndulo Invertido y Grúa ( Pl&G ). Dicha planta se puede describir mediante ecuaciones diferenciales no lineales, donde los términos no lineales complican los aspectos de modelado y de diseño del controlador. Sin embargo, basado en el modelo lineal de la planta, nosotros podemos configurar SSs discretos combinando controladores con observadores no lineales. Resultados experimentales demuestran que cada SS es capaz de estabilizar el PI (o Grúa) montado sobre un carro movido por un servomotor. Tres configuraciones de SSs se presentan y discuten: un Controlador Óptimo Cuadrático de Estado Estable (COCEE) con un Observador de estado Óptimo Cuadrático (OEOC), un Controlador por Ubicación de Polos (CUP) con un Obser...

This article develops design procedures for Proportional Integral Servosystems (abbreviated SS) to control a dual-purpose nonlinear plant: the Inverted Pendulum and Crane (PI&G). Said plant can be described by nonlinear differential equations,where nonlinear terms complicate the modeling and design aspects of the controller.However, based on the linear model of the plant, we can configure discrete SSs by combining controllers with nonlinear observers. Experimental results demonstrate that each SS is capable of stabilizing the PI (or Crane) mounted on a carriage moved by a servomotor. Three configurations of SSs are presented and discussed: an Optimal ControllerSteady State Quadratic (COCEE) with a Quadratic Optimal State Observer (OEOC), a Pole Location Controller (CUP) with a Complete Order State Observer (OEOC), and a CUP with a Minimum Order State Observer (OEOM).

Sabancaya is the most active volcano of the Ampato-Sabancaya Volcanic Complex (ASVC) in southern Perú and has been erupting since 2016. The analysis of ascending and descending Sentinel-1 orbits (DInSAR) and Global Navigation Satellite System (GNSS) datasets from 2014 to 2019 imaged a radially symmetric inflating area, uplifting at a rate of 35 to 50 mm/yr and centered 5 km north of Sabancaya. The DInSAR and GNSS data were modeled independently. We inverted the DInSAR data to infer the location, depth, and volume change of the deformation source. Then, we verified the DInSAR deformation model against the results from the inversion of the GNSS data. Our modelling results suggest that the imaged inflation pattern can be explained by a source 12 to 15 km deep, with a volume change rate between 26 × 106 m3/yr and 46 × 106 m3/yr, located between the Sabancaya and Hualca Hualca volcano. The...

Objective. To evaluate the predictive ability of traditional risk scores and frailty assessment for 30-day mortality in elderly patients undergoing cardiac surgery. Materials and Methods. A single-center retrospective cohort study was conducted, including elderly patients (≥75 years old) who underwent cardiac surgery between January 2005 and December 2015. EuroSCORE II, STS (Society of Thoracic Surgeons) score, Charlson Comorbidity Index, and Electronic Frailty Index scores were calculated to assess their predictive ability for 30-day mortality using receiver operating characteristic (ROC) curves and corresponding areas under the curve (AUC). Results. A total of 203 patients were included during the study period, of whom 33% underwent isolated coronary bypass surgery. The overall 30- day mortality rate was 17.6%. Patients who died within the first 30 days exhibited higher scores on Eur...

Gastric cancer (GC) is the second most common cancer and first leading cause of cancer-related deaths in Peru. Infection by Helicobacter pylori (HP) and Epstein-Barr virus (EBV) are accepted carcinogenic and infection is widely spread in the Peruvian population. The aims of this study were to evaluate HP and EBV-associated GC (EBVaCG), to assess the prevalence rate and to define the characteristics of Peruvian patients. GC samples were prospectively collected from patients who underwent gastroscopy or surgical resection with no preoperative treatment at INEN between 2015 and 2017. Tumor tissue (T), proximal healthy tissue (P) and distal healthy tissue (D) samples were assessed for HP and EBV by quantitative PCR (qPCR) using specific primers. HP and EBV status were analyzed along with clinicopathologic parameters of the tumor. Kaplan-Meier estimation curves overall survival (OS) was appli...