La Història de les matemàtiques dins dels nous currículums de secundària

The new Catalan curriculum of mathematics to Secondary Compulsory Education contents some suggestions to use history of mathematics to teach mathematics. In this paper we present a proposal for training history context in mathematical lessons and we also illustrate it with an example concerning to 3rd year in the official curriculum: solving equations in Arabian World

Aggressor or protector? Experiences and perceptions of violence predict preferences for masculinity

This work was funded by Colciencias (Call 646) and St Leonard's College, University of St Andrews, Scotland.Women’s preferences for masculine male partners have been explained in terms of heritable health. The evidence between masculinity and health, however, is controversial and therefore, alternative explanations for masculinity preferences reflecting income inequality and protection from violence have been proposed. This study thus aimed to test the effect of exposure to violence (i.e., experiences of robberies and perceptions of danger) on the individual masculinity preferences of women and men from the capital city of Colombia, Bogota, and surrounding small towns. One hundred and fifty three adult participants (mean age ± S.D.= 31.3 ± 9.4), all heterosexual, were surveyed in reference to indicators related to health (e.g., drinking water access, frequency of illnesses), access to media (e.g., television and internet access), education (e.g., graduating from high school, attending university) and exposure to violence (e.g., frequency of robberies/attacks, feelings of danger from violence). Participants made two alternative, preference forced-choice for masculinized and feminized versions of both rural Salvadoran and European male faces. We found that men and women exposed to higher levels of violence preferred less masculine male faces, although this effect was only significant for women. Additionally, the effect of violence exposure was more relevant for the Salvadoran stimuli. Violence contributed significantly to explaining masculinity preferences after controlling for participant age, education, access to media, and health-related factors. These preferences may reflect women’s strategy to avoid male violence demonstrating that exposure to violence matters in interpersonal attraction.PostprintPeer reviewe

Genetic algorithm for flexible job shop scheduling problem - A case study

This paper proposes the impact assessment of the workers in the optimal time of operations in a Flexible Job Shop Scheduling Problem. In this work, a real enterprise was studied. The problem consists in finding the workers operations schedule, taking into account the precedence constraints. The main objective is to minimize the finish time of the last task completed in the schedule. The genetic algorithm was used to solve the optimization problem and some numerical results are presented.The research leading to these results has received funding from the European Union Seventh Framework Programme FP7/2007- 2013 under grant agreement n° 314056.info:eu-repo/semantics/publishedVersio

Sufficient Conditions for Fast Switching Synchronization in Time Varying Network Topologies

In previous work, empirical evidence indicated that a time-varying network could propagate sufficient information to allow synchronization of the sometimes coupled oscillators, despite an instantaneously disconnected topology. We prove here that if the network of oscillators synchronizes for the static time-average of the topology, then the network will synchronize with the time-varying topology if the time-average is achieved sufficiently fast. Fast switching, fast on the time-scale of the coupled oscillators, overcomes the descychnronizing decoherence suggested by disconnected instantaneous networks. This result agrees in spirit with that of where empirical evidence suggested that a moving averaged graph Laplacian could be used in the master-stability function analysis. A new fast switching stability criterion here-in gives sufficiency of a fast-switching network leading to synchronization. Although this sufficient condition appears to be very conservative, it provides new insights about the requirements for synchronization when the network topology is time-varying. In particular, it can be shown that networks of oscillators can synchronize even if at every point in time the frozen-time network topology is insufficiently connected to achieve synchronization.Comment: Submitted to SIAD

Wireless Sensor Networks and Real-Time Locating Systems to Fight against Maritime Piracy

There is a wide range of military and civil applications where Wireless Sensor Networks (WSNs) and Multi-Agent Systems (MASs) can be used for providing context-awareness for troops and special corps. On the one hand, WSNs comprise an ideal technology to develop Real-Time Locating Systems (RTLSs) aimed at indoor environments, where existing global navigation satellite systems do not work properly. On the other hand, agent-based architectures allow building autonomous and robust systems that are capable of working on highly dynamic scenarios. This paper presents two piracy scenarios where the n-Core platform can be applied. n-Core is a hardware and software platform intended for developing and deploying easily and quickly a wide variety of WSNs applications based on the ZigBee standard. In the first scenario a RTLS is deployed to support boarding and rescue operations. In the second scenario a multi-agent system is proposed to detect the unloading of illegal traffic of merchandise at ports

La Trigonometria en els inicis de la matemàtica xinesa : algunes idees per treballar a l'aula

The Nine Chapters is the most important old Chinese mathematical text. It contains a chapter devoted to solving problems of triangles (chapter 9). The analysis of the method for solving problems—using the «base and height procedure» or «Gougu » procedure— together with the comprehension of later contributions of commentators led us to use old Chinese conceptions for training the XXI century students

Infrared glucose portable device

There are quite a few persons worldwide with severe issues to control the glucose level on its blood. Only in Mexico, there are about 10 million persons with this disease and well over 13 deaths in 100 in this country are due to diabetes. In order to help to control this health issue, we are proposing a device to measure in a swift, simple and efficient way abnormality glucose levels in blood by using infrared sensors. Glucose shows a high absorbance to infrared wavelength. By using such characteristic, it is possible to develop a mobile, low-cost electronic device capable to analyse a blood sample by measuring the absorbance in it. The process is performed by using an array of infrared diodes controlled by a low-power consumption microcontroller as well as by several algorithms within a case. A blood sample is put in a substrate within the case. Once analysed, the glucose level of such sample is analysed and displayed on a scree