1,088 research outputs found
Selective monostability in multi-stable systems
We propose a robust method that allows a periodic or a chaotic multi-stable system to be transformed to a monostable system at an orbit with dominant frequency of any of the coexisting attractors. Our approach implies the selection of a particular attractor by periodic external modulation with frequency close to the dominant frequency in the power spectrum of a desired orbit and simultaneous annihilation of all other coexisting states by positive feedback, both applied to one of the system parameters. The method does not require any preliminary knowledge of the system dynamics and the phase space structure. The efficiency of the method is demonstrated in both a non-autonomous multi-stable laser with coexisting periodic orbits and an autonomous Rössler-like oscillator with coexisting chaotic attractors. The experiments with an erbium-doped fibre laser provide evidence for the robustness of the proposed method in making the system monostable at an orbit with dominant frequency of any preselected attractor
Project in Entrepreneurship Tintaya Spirit
The present project evaluates the potential of the business idea; the possibility of creating an Eco-hotel on Lobitos Beach, located in the northern coast of Peru; more precisely in the province of Talara, near to Piura city; ideal place with sandy beaches to practice water sports, mainly surfing. And where, despite the presence of some hotels, there is none that stands out for a differentiation in their accommodation and services. Also analyzes its relationship with current industry, the needs of the target market, the ability of entrepreneurs to establish and manage the business, as well as the financial needs of the project. The development of the business idea we want to combine the passion for share our best with people, nature, culture and activities related to the sea, with our knowledge and experience in the field of business administration. Our goal goes beyond creating a profitable and lasting business over time, we also want to highlight the Peruvian culture related to the region, generate a positive impact on all the stakeholders, especially on the environment and the inhabitants of the area
Variations to the cryptographics algorithms AES and TWOFISH
The cryptographic algorithms AES and Twofish guarantee a high diffusion by the use of fixed 4x4 MDS matrices. In this article variations to the algorithms AES and Twofish are made. They allow that the process of cipher - decipher come true with MDS matrices selected randomly from the set of all MDS matrices with the use of proposed algorithm. A new key schedule with a high diffusion is designed for the algorithm AES. Besides proposed algorithm generate new S - box that depends of the key
Argumentation in problem solving: a strategy for learning the concept of linear function
Este artículo presenta los resultados de una práctica docente desarrollada con 19 estudiantes de la institución educativa Gimnasio Campestre de Florencia, donde se indagó sobre los niveles de argumentación de los estudiantes cuando resuelven problemas que involucran el aprendizaje de la función lineal. Como estrategia metodológica, de intervención en el aula, se diseñó una unidad didáctica (UD), que se estructuró en tres momentos: momento de ubicación, momento de desubicación y momento de reenfoque. Cada momento sirvió como espacio para la comprensión y búsqueda de soluciones a problemas con procesos básicos de argumentación mediante prácticas experimentales estructuradas a través de fases, permitiendo llevar el concepto de función lineal a un contexto cotidiano. El análisis muestra que la calidad de los argumentos mejoró sustancialmente cuando se aplicó la UD, permitiendo pasar de niveles de argumentación mínimos a otros niveles de argumentación más altos, según lo planteado por Osbornen, Erduran & Simon (2004).This article presents the results of a teaching practice developed with 19 students from the educational institution Gimnasio Campestre de Florencia, where the students' levels of argumentation were investigated when solving problems involving the learning of the linear function. As a methodological strategy for intervention in the classroom, a didactic unit (DU) was designed, which was structured in three moments: moment of location, moment of dislocation and moment of refocusing. Each moment served as a space for understanding and searching for solutions to problems with basic argumentation processes through experimental practices structured through phases, allowing the concept of linear function to be brought into a daily context. The analysis shows that the quality of the arguments improved substantially when the UD was applied, allowing to go from minimum levels of argumentation to other higher levels of argumentation, as suggested by Osbornen, Erduran & Simon (2004)
Experimental implementation of a biometric laser synaptic sensor
We fabricate a biometric laser fiber synaptic sensor to transmit information from one neuron cell to the other by an optical way. The optical synapse is constructed on the base of an erbium-doped fiber laser, whose pumped diode current is driven by a pre-synaptic FitzHugh–Nagumo electronic neuron, and the laser output controls a post-synaptic FitzHugh–Nagumo electronic neuron. The implemented laser synapse displays very rich dynamics, including fixed points, periodic orbits with different frequency-locking ratios and chaos. These regimes can be beneficial for efficient biorobotics, where behavioral flexibility subserved by synaptic connectivity is a challenge
Análisis industrial de la reducción del óxido de hierro mediante la inyección de finos de carbón al horno eléctrico de arco
Annotations for Rule-Based Models
The chapter reviews the syntax to store machine-readable annotations and
describes the mapping between rule-based modelling entities (e.g., agents and
rules) and these annotations. In particular, we review an annotation framework
and the associated guidelines for annotating rule-based models of molecular
interactions, encoded in the commonly used Kappa and BioNetGen languages, and
present prototypes that can be used to extract and query the annotations. An
ontology is used to annotate models and facilitate their description
Contenido de compuestos Fenólicos y actividad antioxidante del arazá (Eugenia stipitata Mc Vaugh) en diferentes estados de maduración.
El Arazá(Eugenia stipitataMc Vaugh), despierta gran interés en dif'erentes ámbitos por las cualidades organotépticas dcl fruto y por el índice de producción de la planta. Con el objetivo de evaluar el potencial antioxidante del Arazá cultivado en el Departamento Caquetá. se evaluó la actividad de los extractos acuosos de la pulpa de Arazá en 5 dif'erentes estados de maduración (.A1: Vcrde: 42: Verde madurol A3: Pintón; A4: Maduro y 45: Sobre maduro), empleando las metodologías dc DPPH yABTS. 1, se cuantificó el contenido total dc f'enoles usando el ensayo cle Folin-Ciocalteu acorde con el método desamollado por Velioglu. Los resultados indican que la mayor actividad antioxidante la prcsentan las fnrtas de arazá en estado de maduración 43. con valores TEAC-DPPH de 81,9 ¡rmol trolox/l00 g extracto seco y TEAC- ABTS de 241,8 ¡unol trolox/I00 g extracto seco. En este mismo estado de maduración se encontró el mayor contenido de l'enoles totales (1063,9 rng ácido ascó¡bico/I00 g de extracto seco), por lo tanto, principalmentc a cstos compucstos fenólicos, puede ser atribuida la actividad antioxidante
Transfusion related acute lung injury: a case report
Transfusion Related Acute Lung Injury (TRALI) is one of the most serious complications of blood transfusion. All blood components have been implicated and most often those that contain plasma. The diagnosis is based fundamentally on the integration of clinical, radiological and gasometry elements, once the rest of the possible causes of acute lung injury have been ruled out. The differential diagnosis of a patient who develops a sudden pattern of respiratory failure after a transfusion of blood products must include hemodynamic overload, anaphylactic reaction, bacterial contamination of transfused blood products, haemolytic transfusion reaction and TRALI. Author presented the clinical case of a 33-year-old female patient with grade III hypovolemic shock due to a ruptured ectopic pregnancy, reanimated with crystalloid solutions, globular packages and fresh frozen plasma. The patient developed TRALI for what was managed with ventilatory and hemodynamic support in ICU
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