Demo 21. Cuerpos cargados y el electroscopio

Objetivo: Mostrar la carga de objetos por fricción, mediante el uso de un instrumento clásico como el electroscopio, en el que se pone de manifiesto la fuerza electrostática y la conservación de la carga

Demo 48. Histéresis magnética

Objetivo: Mostrar la presencia de dominios magnéticos en un medio ferromagnético, su evolución en presencia de un campo magnético externo, visualizando el fenómeno de histéresis

Demo 100. Atracción electrostática con vidrio y plástico

Objetivo: Mostrar la atracción o repulsión entre cargas eléctricas

Demo 32. Ley de Ampère: fuerza entre corrientes

Objetivo: Mostrar en un sencillo experimento una de las bases fenomenológicas más importantes del Electromagnetismo, como es la ley de Ampère, poniendo de manifiesto la fuerza de atracción o repulsión entre dos bobinas recorridas por una corriente

Fuzzy logic-based assessment adjust of multiple choice questionnaires

In University environment, it is common to use multiple-choice objective tests with three or four possible answers, of which only one is correct and the rest are erroneous. In this type of tests, usually the wrong answers are penalized in order to avoid the effect of the random answers. However, there are questions that hardly students answer since their difficulty is high. On the other hand, there are also questions that answer virtually all students since their difficulty is simple. While sometimes the course professor chooses to suppress these questions, it is also common to leave them as part of the calculation of the overall score. This communication proposes a way of, without suppressing any question, making a readjustment of the grades based on fuzzy logic techniques. To do this, it is considered, on the one hand, the initial grade obtained by each student and, on the other, the total difficulty index of the test. With these two variables, an approximation can be made to a system of linguistic variables that allows correcting the final grades of each student based on the objective difficulty of the test and a set of rules established by the professor. This will revert to greater “justice” in students’ mark system, since it will be a function of the difficulty of the test.Postprint (published version

Demo 33. Inducción electromagnética y el transformador

Objetivo: 1.- Observar fenómenos de inducción mediante elementos móviles. 2.- Observar fenómenos de inducción mediante corrientes variables con el tiempo. 3.- Establecer la estructura de un transformador de eléctrico

A contribution to students' assessment adjusts of multiple choice questionnaires with fuzzy logic

In University environment, it is common to use multiple-choice objective tests with three or four possible answers, of which only one is correct and the rest are erroneous. In this type of tests, usually the wrong answers are penalized in order to avoid the effect of the random answers. However, there are questions that hardly students answer since their difficulty is high. On the other hand, there are also questions that answer virtually all students since their difficulty is simple. While sometimes the course professor chooses to suppress these questions, it is also common to leave them as part of the calculation of the overall score. This communication proposes a way of, without suppressing any question, making a readjustment of the grades based on fuzzy logic techniques. To do this, it is considered, on the one hand, the initial grade obtained by each student and, on the other, the total difficulty index of the test. With these two variables, an approximation can be made to a system of linguistic variables that allows correcting the final grades of each student based on the objective difficulty of the test and a set of rules established by the professor. This will revert to greater “justice” in students’ mark system, since it will be a function of the difficulty of the test.Postprint (published version

The relationship between knowledge management and innovation level in Mexican SMEs: Empirical evidence

The transformation of the current society from an industry-based economy to a knowledge management and innovation-based economy is changing the design and implementation of business strategies and the nature of the competition among the organizations which are mainly small and medium-size enterprises (SMEs). They struggle to survive in a market which is more demanding and competitive, so they seeknowledge management as one of the most effective strategies that may help to enable the innovation activities into the businesses. For these reasons, this research paper has as a main goal to analyze the relationship between knowledge management and innovation in Mexican SMEs. The empirical analysis used 125 manufacturing SMEs (each SME having from 20 to 250 employees) as a sample to be carried out. The obtained results indicate that knowledge management has a positive impact in products, process, and management systems innovation