Ultrahigh birefringence index-guiding photonic crystal fiber

Author name used in this publication: Ming-Leung Vincent TseRefereed conference paper2013-2014 > Academic research: refereed > Refereed conference paperVersion of RecordPublishe

Do it for the group: Developing digital competencies with Global Virtual Teams

[EN] The EU established a framework of digital competencies for citizens aimed at improving their skills in a professional environment. Bearing that in mind, this study observes the implementation of some of the competencies within an academic cross-cultural project. Through the organisation of a Global Virtual Team activity, two Higher Education Institutions, one in Spain and the other one in Belgium, carried out a monitored activity with identical learning objectives in which students had to organise a trip to the partner city. Teachers divided the students (n=127; 72 in Spain and 55 in Belgium) in groups and each group was paired with another one in the partner institutions. The purpose was to support each other in the best manner to reach the goal of preparing the trip for their own peers following some clear-cut requirements. The activity proved to be satisfactory in several areas, demonstrating the convenience of organising Global Virtual Teams as part of the study plan of a course. Previous literature has shown the advantages of putting these activities into practice, as they also facilitate learning required skills within a professional context and allow the creation of international projects without leaving their own institution. Likewise, students in both institutions expressed their satisfaction with the results and performance through the many obstacles encountered. At the same time, this study sheds new light on the importance of monitoring carefully the progress of students and strengthening academic and personal links.The authors would like to express their gratitude to the students in both institutions taking part in the project and providing valuable, constant feedback in the process. Similarly, the authors are grateful to the support of Kathleen Galle and Ellen Thielemans, lecturers at Erasmushogeschool Brussel, for their constant support and deep interest in collaborating in this study.Planells-Artigot, E.; Ortigosa Blanch, A. (2021). Do it for the group: Developing digital competencies with Global Virtual Teams. En Proceedings INNODOCT/20. International Conference on Innovation, Documentation and Education. Editorial Universitat Politècnica de València. 195-202. https://doi.org/10.4995/INN2020.2020.11885OCS19520

Peruse this! Use of an educational social platform for a Global Entrepreneurship flipped class

[EN] The COVID-19 pandemic made all of our universities to move to a full-online teaching scheme this March. Online teaching presents different drawbacks compared to classroom teaching, but probably the main one is the difficulty to keep the interactivity with the students throughout the online sessions. This is why a flipped classroom scheme becomes even more relevant in the new normal.A key aspect for a flipped class is that the information transfer, traditionally performed through lectures, is moved out of the classroom to different types of pre-class assignments. Students are expected to fulfill those assignments before the class allowing the instructor to engage in more interactive activities with the students in the classroom. Nevertheless, getting students to read the proposed contents before the class is a very important problem in higher education. In this work, we show the results of the implementation of pre-class reading assignments in a Global Entrepreneurship course through an educational social platform that allows students to discuss the reading online with their classmates: PERUSALL. We use the platform to understand how students are reading and understanding the different materials, their reading behaviors and how the instructor can take advantage of all that information. Considering the type of group (50 students, 65% of them international students from exchange programmes we have also performed a survey to assess the platform and evaluate the perception of the students of their learning process.The authors would like to thank the students enrolled in the Global Entrepreneurship course for their good work during the semester and for answering the questionnaire even though they already knew their final grades. A. Ortigosa-Blanch would like to acknowledge financial support from ESIC Business&Marketing Scholl under project ESIC-V-1-2017 and for the international travel grant to attend the IAP Program, Transforming Higher Education in the Digital Age, that enabled him to meet Prof. Eric Mazur and the Perusall platform.Ortigosa Blanch, A.; Planells-Artigot, E. (2021). Peruse this! Use of an educational social platform for a Global Entrepreneurship flipped class. En Proceedings INNODOCT/20. International Conference on Innovation, Documentation and Education. Editorial Universitat Politècnica de València. 111-119. https://doi.org/10.4995/INN2020.2020.11855OCS11111

Temperature independence of birefringence and group velocity dispersion in photonic crystal fibres

Experimental results are presented for the dependence of the dispersion and the birefringence of a highly birefringent photonic crystal fibre with temperature. It is shown that, unlike conventional optical fibres, where temperature induces stress regions between the different materials present in their structure, photonic crystal fibres exhibit no dependence with temperature of these optical properties owing to the single material nature of their structures

Wavelength-codified fiber laser hydrogen detector

We report a scheme for an optical hydrogen detector that codifies the information in wavelength. The system is based on an erbium-doped fiber laser with two coupled cavities and a Palladium-coated tapered fiber within one of the laser cavities. The tapered fiber acts as the hydrogen-sensing element. When the sensing element is exposed to a hydrogen atmosphere, its attenuation decreases changing the cavity losses. This change leads the system to switch lasing from the wavelength of the auxiliary cavity to the characteristic wavelength of the cavity which contains the sensing element. The detection level can be shifted by adjusting the reflective elements of the cavity containing the sensing element

High-power Soliton-induced Supercontinuum Generation and Tunable Sub-10-fs VUV Pulses from Kagome-lattice HC-PCFs

We theoretically study a novel approach for soliton-induced high-power supercontinuum generation by using kagome lattice HC-PCFs filled with a noble gas. Anomalous dispersion and broad-band low loss of these fibers enable the generation of two-octave broad spectra by fs pulses, with high coherence and high spectral peak power densities up to five orders of magnitude larger than in standard PCFs. In addition, up to 20 percents of the output radiation energy forms a narrow UV/VUV band, which can be tuned by contolling the pressure in the range from 350 nm to 120 nm. In the temporal domain this corresponds to sub-10-fs UV/VUV pulses with pulse energy of few tens of microjoule, caused by the formation of a high-order soliton emitting non-solitonic radiation.Comment: 4 pages, 4 figure

Estudio Ecográfico de la laringe en cantantes niños y adultos

Presentamos un estudio ecográfico realizado en cantantes niños y adultos. Mediante ecografía se ha visualizado y analizado el comportamiento de los pliegues vocales durante la respiración tranquila y durante distintas vocalizaciones. Los resultados obtenidos muestran que la técnica ecográfica presenta mayor resolución en el caso de los niños y niñas que en los adultos. En estos últimos, la visualización es mejor en las mujeres que en los hombres. Dado que la ecografía permite captar procesos dinámicos en tiempo real, se han realizado diversas filmaciones de los pliegues vocales durante la emisión de voz. Se ha pedido a dos cantantes, una soprano y una contralto, que realizaran una nota grave y una aguda. En ambos casos los pliegues vocales tienen un comportamiento análogo, observándose en el caso de las notas agudas una mayor tensión de los pliegues durante la fonación. Creemos que la ecografía es una técnica muy interesante para el estudio de la laringe en cantantes, ya que es una técnica no invasiva y por ello puede ser usada en niños y adultos sin ningún efecto secundario adverso

Patrones musculares en el canto. Un estudio piloto.

En estudios electromiográficos realizados previamente en diferentes cantantes, observamos cómo durante la emisión de la voz se producía la activación de los músculos espiradores y en paralelo se producía la contracción de los músculos intercostales externos, potentes inspiradores. Dadas estas observaciones, hemos realizado un estudio piloto con una cantante analizando el comportamiento conjunto de los músculos antes mencionados y del diafragma. Durante dife - rentes vocalizaciones hemos medido paralelamente la actividad muscular con electromiografía (EMG) y hemos observado el retorno diafragmático mediante ecografía. Los resultados apuntan a que el ascenso del diafragma está directamente relacionado con la nota emitida. Así, en el caso de una nota grave, el diafragma retorna lentamente acompañando el sonido. En el caso de las notas agudas, el diafragma se mantiene casi inmóvil durante la mayor parte de la emisión sonora y sólo al final de la vocalización se produce su ascenso de manera lenta. Se observa que durante la espiración en el canto, los músculos intercostales ex - ternos actúan elevando y fijando las costillas lo que impide el ascenso libre del diafragma, que se mantiene en tensión y se eleva de manera lenta y controlada gracias a la presión ejercida por los músculos del abdome