Revista Cubana de Física

In this paper, we present an architectural and electrical design of an integrated A/D converter configuration, based on ΔΣ modulation, for data acquisition from an ISFET (Ion Sensitive Field Effect Transistor) microsensor, applied to the development of a Smart ISFET. This A/D architecture in continuous-time, incorporates the microsensor as a component of the integrated circuit, together the required electronics for the automatic correction of the ISFET´s offset fulfilling the necessary requirements for the development of a portable device.

The rapid development of technology has enabled many types of technology to be used frequently by educators in learning and teaching activities. One of these frequently used educational technologies is Arduino. Arduino is one of the technological tools used in physics teaching. This study aims to determine how resistance changes depending on the cross-sectional area, length, and resistivity of the conductor using Arduino. In order to determine the factors affecting the resistance in the Arduino-based experiment, the experiment utilized the graphite leads that students use in their daily lives. An inexpensive and high mobility experiment system has been developed. The data obtained by the experimental setup complies with theoretical laws. This experiment, along with the use of Arduino, will enable students to experience Ohm's law and enable them to better understand the concepts of potential, current, and resistance in a series circuit. In addition, it is thought that the experiment will attract more attention from students by offering a technology-supported learning opportunity. The fact that the materials in the experiment are materials used by students in their daily life can improve students' science process skills. Researchers and teachers can turn this experiment into a STEM activity by integrating it into a problem situation.

The search for binary sequences with low auto-correlations (LABS) is a computationally hard discrete combinatorial optimization problem. We explore two physically inspired algorithms to explore the low energy space of this model. The greedy, T = 0, Monte Carlo (MC) method gets trapped in the exponentially many 1-Spin-Flip stable configurations, that are typically low in energy, but still far from the global optimum. The more elaborated Warning Propagation (WP) algorithm also gets trapped in local minima. However, these local minima, are more stable to spin flips than the ones obtained by the greedy MC. We also compare the behavior of both algorithms in randomized versions of LABS, showing that the low energy space of the 4-Spin model is easier to explore than the one of LABS.

An alternative analysis of the physical interpretation of the NUT solution is carried out, using the bar structure method of axial-symmetric solutions in Weyl coordinates. Obtaining that the NUT solution can be interpreted as two counter-rotating bars of infinite rotation and with identical masses and a central static bar of different mass.

In this work, an educational tool for teaching numerical bisection and secant methods through its hardware implementation with an Arduino Due based card is presented. It is an accessible practice for the university level in which students who are not familiar with the programming languages ​​can learn both numerical methods and the Arduino programming language due to its accessibility and simplicity. To verify results and as a means of debugging programs in the Arduino language, a spreadsheet is also used. As a case study, the classic problem of the 4-bar mechanism is revisited from a technological perspective, using a 32-bit microcontroller as a calculation tool. It is expected that development of traditional practices which are reviewed from a technological approach applied to real case studies, will encourage students to develop new prototypes and tangible technological developments by using the software and hardware tools to implement algorithms of numerical methods that solve complex engineering and physics problems.