Photonic Logic Based on Molecular Reorientation of Nematic Liquid Crystals

A new type of photonic logic, based on the use of nematic liquid crystals is proposed. The system takes advantage of the refractive-index changes induced by laser beams. Examples of AND, OR and NOR functions are presented

Cálculo de las características de transmisión de una fibra de índice gradual mediante el empleo de su matriz ABCD

Se desarrolla, en el presente trabajo, un nuevo método para el cálculo de la dispersión temporal de la radiación óptica que se propaga a través de una fibra de Índice gradual mediante el empleo de la matriz ABCD de dicha fibra. Este método de una mayor simplicidad que los usados habitualmente, proporciona análogos resultados a los ya presentados en la literatura del tema con la ventaja de su mayor facilidad de cálculo

Human Head Natural Protection Against Electromagnetic Fields

In this paper we provide concluding evidence that the human skull acts as a dynamic barrier to electromagnetic fields (EMF) and temperature flow at 1800 MHz. This natural helmet e®ectively and dynamically protects brain tissue against safety-de¯ned threshold temperature increase due to external EMF induction. A half-wavelength dipole antenna has been employed as the EMF source. The human head is modelled by several coronal planes extracted from the Visible Human Project. Results described here have a great importance should thermal e®ects be directly used to derive basic restrictions to EM fields safety limits for human exposure.FUNDACIÓN SENECA. Plan de Ciencia y Tecnología de la Región de Murcia. Código: 05746/PI/07

Your Teammate Just Sent You a New Message! The Effects of Using Telegram on Individual Acquisition of Teamwork Competence

[EN] Students’ acquisition of teamwork competence has become a priority for educational institutions. The development of teamwork competence in education generally relies in project-based learning methodologies and challenges. The assessment of teamwork in project-based learning involves, among others, assessing students’ participation and the interactions between team members. Project-based learning can easily be handled in small-size courses, but course management and teamwork assessment become a burdensome task for instructors as the size of the class increases. Additionally, when project-based learning happens in a virtual space, such as online learning, interactions occur in a less natural way. This study explores the use of instant messaging apps (more precisely, the use of Telegram) as team communication space in project-based learning, using a learning analytics tool to extract and analyze student interactions. Further, the study compares student interactions (e.g., number of messages exchanged) and individual teamwork competence acquisition between traditional asynchronous (e.g., LMS message boards) and synchronous instant messaging communication environments. The results show a preference of students for IM tools and increased participation in the course. However, the analysis does not find significant improvement in the acquisition of individual teamwork competence.S

Lie theory: applications to problems in Mathematical Finance and Economics

This paper is devoted to show and explain some applications of Lie theory to solve some problems in Economics and Mathematical Finance. So we put forward and discuss mathematical aspects and approaches for several economic problems which have been previously considered in the literature. Besides we also show our advances on this topic, mentioning some open problems for future research

The effect of partial loads on the performance of a funnel solar cooker

Several solar cooker designs have been proposed over the last decades. The funnel cooker is a well-known model, representative of the category of panel-type solar cookers. From the empirical experience of real practice, it is known that the use of partial loads has an impact on the performance of the cooker. However, this effect has not yet been investigated rigorously. This work aims to fill this lack. Extensive experimental work was performed to determine the effect of partial loads on a funnel cooker thermal performance. Tests were conducted on two identical funnel cookers, in Malaga, Spain, with low sun elevation. Cookers were tracked only azimuthally. Experimental protocol was based on ASAE 580.1 Standard for better replicability. Results showed that the standardised power drops by about 15% of the original value when the water volumetric load fraction drops by 25%, for both cooker operations, with and without glass enclosure. This important reduction is explained on how the fill level of the cooking vessel affects its function as a thermal radiation receiver. Results from experimental tests were correlated into a simple formula of practical interest. Finally, a new cooking vessel design, that improves performance at partial loads, i.e., a 25.4% increase in cooker power, was proposed and testedFunding for open access charge: Universidad de Málaga / CBU

Un ejercicio de acceso a la información sobre la eficiencia en el combate contra la trata de personas en México1

ResumenUn ejercicio de acceso a la información sobre la eficiencia en el combate a la trata de personas en México contiene tres apartados: Metodología, Acceso a la información, Procuración e impartición de justicia en materia de trata de personas, así como sus respectivas conclusiones. La trata de personas, denominada “la esclavitud del siglo xxi”, es el comercio de seres humanos que reviste distintas modalidades, entre ellas, la explotación sexual, la explotación laboral, la mendicidad forzada, la extracción de órganos, el matrimonio forzoso, trabajo o servicios forzados y la experimentación biomédica ilícita.El Observatorio Nacional Ciudadano de Seguridad, Justicia y Legalidad presenta este texto con el objetivo de describir parte de lo que sucede en la cadena de justicia en la materia, por lo que se generaron bases de datos estadísticos de la información oficial disponible sobre el número de víctimas que de 2010 a 2013 han detectado las procuradurías estatales; el número de detenidos y sentenciados por este delito; el perfil de las víctimas, y cómo y dónde se realiza el delito. Los resultados demuestran que hay un 2% de efectividad en relación con el número de víctimas, en contraste con el de sentencias condenatorias; y en contraste con el incumplimiento de las entidades y la federación, quienes no generan información estadística confiable y de fácil acceso, lo cual es su obligación. Lo anterior pone en evidencia la falta de una política pública contundente para combatir este fenómeno, debido a que no se cuenta con un diagnóstico oficial sobre las dimensiones y gravedad de este problema en nuestro país.AbstractAn exercise of access to information on the efficiency in combating trafficking in persons in Mexico, contains three sections: Methodology, Access to Information, Procurement and delivery of justice in human trafficking, and their respective conclusions. Trafficking known as slavery of the XXI century is the trade in human beings that takes different forms, including sexual exploitation, labor exploitation, organ removal, forced marriage, forced labor or services and illicit biomedical experimentation.Observatorio Nacional Ciudadano presents this text with the aim of describing what happens in the chain of justice in the matter, statistical databases of official information were generated to measure, with the available information, the number of victims from 2010 to 2013 the state prosecutors have detected, the number of detainees and convicted of this crime, the victim profile, how and where the offense is committed. The results show that there is a 2% success rate in relation to the number of victims in contrast to that of convictions; entities and federation fail to meet the obligation to generate reliable statistical information and easily accessible. This highlights the lack of a strong public policy to combat this phenomenon, because there is no official diagnosis of the extent and severity of this problem in our country

Your Teammate Just Sent You a New Message! The Effects of Using Telegram on Individual Acquisition of Teamwork Competence

Students’ acquisition of teamwork competence has become a priority for educational institutions. The development of teamwork competence in education generally relies in project-based learning methodologies and challenges. The assessment of teamwork in project-based learning involves, among others, assessing students’ participation and the interactions between team members. Project-based learning can easily be handled in small-size courses, but course management and teamwork assessment become a burdensome task for instructors as the size of the class increases. Additionally, when project-based learning happens in a virtual space, such as online learning, interactions occur in a less natural way. This study explores the use of instant messaging apps (more precisely, the use of Telegram) as team communication space in project-based learning, using a learning analytics tool to extract and analyze student interactions. Further, the study compares student interactions (e.g., number of messages exchanged) and individual teamwork competence acquisition between traditional asynchronous (e.g., LMS message boards) and synchronous instant messaging communication environments. The results show a preference of students for IM tools and increased participation in the course. However, the analysis does not find significant improvement in the acquisition of individual teamwork competence

The role of polarization diversity for MIMO systems under rayleigh-fading environments

Polarization diversity techniques have not received as much attention as others due to the significant difference in mean signal level between copolarized and cross-polarized branches when one polarization is transmitted. However, multiple- input–multiple-output (MIMO) systems where the multipath fading is only partially correlated could use polarization diversity to provide a high diversity gain. Hence there is a need to fully understand the role of true polarization diversity in such systems. In this letter, progressive (true) polarization diversity performance for 3 3 MIMO systems under Rayleigh-fading environments is evaluated through simulations and measurements. True polarization diversity was found to be as significant as spatial diversity at improving diversity gain, and hence MIMO system capacity.This work was supported in part by Fundación Séneca, the R&D coordinating unit of the Autonomous Region of Murcia (Spain) under project reference 2I05SU0033. The authors wish to thank Bluetest AB for its generous educational discounting