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Many educational buildings of Colombian public universities urgently require structural reinforcement interventions. However, due to the urban planning considerations of most university campuses, these educational buildings are separated by green areas and access structures. In contrast, the latter is generally characterized by a lack of information on their boundary conditions and material properties, with the aggravating circumstance that, in many cases, they are structurally connected to educational buildings. This article presents a methodology for the structural characterization of an access structure for educational buildings located at the headquarters of the Industrial University of Santander. Ambient vibration field tests allow for studying the influence of boundary conditions. Finally, implementing an algorithm for the optimal location of sensors and numerical tests of forced vibration enables validation of the consistency of the methodology proposed in this article. [ABSTRACT FROM AUTHOR]

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Introduction. Masticatory efficiency (ME) is the individual ability to achieve crushing and grinding, with the help of saliva, through an undetermined number of masticatory cycles. The maximum bite force in kilograms force (MBF/kgf) is the maximum force generated between the teeth of both arches. Objective. To relate MBF/kgf and ME in patients with and without posterior teeth (PT). Methodology. Cross-sectional, observational, and descriptive study. Forty patients who attended in the Masticatory Physiology Laboratory of the Universidad Autónoma Metropolitana-Xochimilco, Ciudad de México, who previously voluntarily they accepted informed consent, were registered; divided into two groups: group A, 20 subjects with complete PT; and group B, 20 with incomplete PT. The ME recording technique consisted of measuring the degree of crushing of silicone tablets by condensation, with a diameter of 20 mm by 5 of thick and 2.03 g, the fragments were collected to perform the sieve (Mesh). The MBF/kgf recordings were made with the T-Scan® EH-2 system, positioning the sensor between the arches, exerting the MBF for 28 sec. Results. Of the 40 subjects, 18 (45%) were female and 22 (55%) males, with a mean age of 23.88 ± 9.6 years. In group A, the MBF/kgf was 35.65 ± 10.30, and the MP was 62.51 ± 21.99. In group B, the MBF/kgf was 20.61 ± 13.45 and the MP was 47.20 ± 25.73. Conclusions. The importance of the relationship between PT in relation to MBM/kgf, and ME was observed, which showed that patients with incomplete dentures present less trituration and grinding, which can directly affect the digestive system, therefore, the need to keep the highest number of PT in the mouth was demonstrated. [ABSTRACT FROM AUTHOR]

Quadrature encoders are the most widely used sensors to measure the position, speed and acceleration of motors. For its proper functioning, it is required the implementation of decoding circuits based on the pulse count and the determination of the direction of rotation of the motor shaft, considering the efficient use of resources and the elimination of errors. Such circuits are usually implemented in microcontrollers-based or microprocessors-based platforms. However, FPGAs have characteristics that make them ideal for this type of application. In this work, a custom IP for the conditioning of four quadrature encoders is presented, which generates count values for each encoder on a time base that can be determined internally or externally and eliminate the errors that occur in the changes of the direction of rotation. The simulation results of the hardware description and its implementation in an FPGAbased mobile robot are presented. [ABSTRACT FROM AUTHOR]