Design of highly focused fields that remain unpolarized on axis

Research on the properties of highly focused fields mainly involved fully polarized light, whereas partially polarized waves received less attention. The aim of this Letter is to provide an appropriate framework, for designing some features of the focused field, when dealing with incoming partially polarized beams. In particular, in this Letter, we describe how to get an unpolarized field on the axis of a high numerical aperture objective lens. Some numerical results that corroborate theoretical predictions are provided.

Exploring new criteria to design materials for online education

Peer-reviewed

User-Centered Design Gymkhana

The User-centered design (UCD) Gymkhana is a tool for human-computer interaction practitioners to demonstrate through a game the key user-centered design methods and how they interrelate in the design process.The target audiences are other organizational departments unfamiliar with UCD but whose work is related to the definition, cretaion, and update of a product service.

Creating a research network for a successful e-portfolio design and implementation

The presence of e-portfolios in educational centres, companies and administrations has emergedstrongly during the last years by creating very different practices coming from different objectives and purposes. This situation has led researchers and practitioners to design and implement e-portfolios with little reference to previous knowledge of them; consequently, developments are disparate with many of the processes and dimensions used both in development and use being unnecessary complex. In order to minimize the inconveniences, unify these developmental processes and improve the resultsof implementation and use of e-portfolios, it seemed necessary to create a network of researchers, teachers and trainers coming from different universities and institutions of different kinds who are interested in the investigation and the practice of e-portfolios in Spain. Therefore, The Network on e-portfoliowas created in 2006, funded by the Spanish Ministry of Education and led by the UniversitatOberta de Catalunya. Besides the goals associatedwith the creation of this network and which wewanted to share with other European researchers and experts of other continents, we will also present in this paper some data concerned with the first study carried out on the use of e-portfolios in our country that shows where we are and which trends are the most important for the near future.

Liderazgo y dirección de empresas en el s. XXI

Peer-reviewed

Mechanical Design of Hydraulic Vise

The general task of clamping devise is to connect the parts to the machining centers so that the work piece could be fixed on its position during the whole machining process. Additionally, the work piece should be clamped easily and rapidly by the machine users. The purpose of this Master’s thesis project was to develop a product design and find out the dimensioning of a hydraulic vise system for Astex Engineering OY, which was taking care of the general principles of product design and development during the design process. Throughout the process, the needs of manufacturing and assembling were taken into consideration for the machinability and minimization of the cost of manufacturing. The most critical component of the clamping devise was modeled by FEM for the issue of strength requirements. This 3D model was created with Solidworks and FEM-analysis was done with Cosmos software. As the result of this design work, a prototype of the hydraulic vise was manufactured for Astex Engineering OY and the practical test.

DFM(A)- aspects for a fixed electrical attenuator design

The goal of this paper is to describe a complete and extensive prototype design of a fixed electrical attenuator. The paper starts by describing the function and by giving some basic information about the attenuators. After a comprehensive description of the component, the facts of reverse engineering are discussed. The method itself is applied to ease manufacturing and design stages of this component. Information about materials and applied manufacturing technologies are also included in this report. By applying some specified DFMA-aspects the final design turned out to be a potential prototype device to be manufactured and for further analyse.

DFM(A)- aspects for a microwave waveguide ring resonator design

In this research manufacturability analysis is made for an E-plane waveguide ring resonator. About the electrical characteristics of the waveguide ring resonator is discussed. Possibilities to utilize concurrent engineering method both for designing and making manufacturability analysis for MW- and RF-components are discussed. For helping to establish the necessary guidelines for easy manufacturing and assembly of the waveguide ring resonator a specialised DFM(A)-questionnaire is generated. The questionnaire gives also new information for collaborative designing approach in MW-/RF- engineering. The advantages and disadvantages of the concurrent engineering design method are evaluated in the research.

DFM(A)- aspects for a horn antenna design

In this paper aspects of design for manufacturability and assembly (DFMA) are applied to the design of coaxially fed standard gain horn antenna for 1.70 - 2.60 GHz. Possibilities to utilize cross-technological approach method is examined. Methods of DFMA for laser processing are covered and practical design guides and methods are developed. Antenna construction for easy manufacturing and specialized performance is shown. Required dimensions and tolerances are discussed and suitable materials for laser processing are selected.

DFM(A)- aspects for an sma connector design

In this research, manufacturability analysis is made for an SMA connector. Analysis and aspects of applying virtual prototyping for an SMA connector design and manufacturing are also investigated. Special questionnaires for the component and machining are made in order to enable necessary information to ensure DFM(A) –aspects of products. The aspects of easy manufacturing for machining the SMA connector are collected. Material selection is discussed, and manufacturing stages of prototype manufacturing are presented. The main focus of this research is on prototype manufacturing, but also aspects considering volume production are discussed. A special purpose SMA connector is designed for printed circuit board edge mounting.

DFM/DFMA(A) – analysis and aspects of applying systematic engineering for a microwave testfixture design

In this paper, manufacturability analysis and collection of design aspects is made for a microwave test-fixture. Aspects of applying systematic design for a microwave test-fixture design and manufacturing are also analysed. Special questionnaires for the component and machining are made in order to enable necessary information to ensure DFM(A) – aspects of the component. The aspects of easy manufacturing for machining the microwave test-fixture are collected. Material selection is discussed and manufacturing stages of prototype manufacturing are presented.

Design and evaluation of learning algorithms for dynamic resource management in virtual networks

Network virtualisation is considerably gaining attentionas a solution to ossification of the Internet. However, thesuccess of network virtualisation will depend in part on how efficientlythe virtual networks utilise substrate network resources.In this paper, we propose a machine learning-based approachto virtual network resource management. We propose to modelthe substrate network as a decentralised system and introducea learning algorithm in each substrate node and substrate link,providing self-organization capabilities. We propose a multiagentlearning algorithm that carries out the substrate network resourcemanagement in a coordinated and decentralised way. The taskof these agents is to use evaluative feedback to learn an optimalpolicy so as to dynamically allocate network resources to virtualnodes and links. The agents ensure that while the virtual networkshave the resources they need at any given time, only the requiredresources are reserved for this purpose. Simulations show thatour dynamic approach significantly improves the virtual networkacceptance ratio and the maximum number of accepted virtualnetwork requests at any time while ensuring that virtual networkquality of service requirements such as packet drop rate andvirtual link delay are not affected.

Museos y periodistas. Análisis de la sala de prensa virtual como espacio de relaciones públicas

Las rutinas de producción periodística se vieron alteradas con la aparición de Internet y la evolución de las fuentes 2.0. Se han extendido los espacios virtuales corporativos para los medios de comunicación, entendidos como herramienta básica de Relaciones Públicas. Los responsables de las organizaciones museísticas han entendido la necesidad de establecer un vínculo relacional con los periodistas en la red, a través de los sitios web oficiales de los museos. No obstante, concluimos que no facilitan los contenidos necesarios para transmitirlos de forma apropiada.

Recerca avaluativa sobre el programa “LÍMITS”

Des de la comunitat científica s’ha posat de manifest la necessitat d’avaluar els programes d’intervenció per a la millora de la parentalitat, especialment en el context de la infància i adolescència en risc. En aquesta recerca es presenten els resultats de l’avaluació del programa Límits aportant evidències d’eficàcia i efectivitat, que permeten identificar i descriure les seves fortaleses, així com també aquells elements que poden ser objecte de millora. El programa Límits és una proposta estructurada d’intervenció preventiva de caire selectiu amb grups de famílies de joves d’entre 14 i 18 anys que passen pel circuit de la justícia juvenil. El programa ha estat funcionant des del 2007, en diverses edicions, a tot el territori català aplegant una experiència i trajectòria remarcable que ha incidit en 351 persones i 245 famílies. El programa consta de vuit sessions en grup d’entre dotze i quinze participants, dinamitzat per dos monitors, en les que es treballen diferents estratègies a partir de l’abordatge de continguts relacionats amb les relacions i els lligams, la comunicació, els conflictes, l’establiment de normes i la disciplina. Per dur a terme l’avaluació del programa Límits s’ha partit d’un disseny quasi-experimental, pretest–postest aplicat a un grup programa (GP) i a grup col·laborador (GC) i de manera diferida (dos mesos després de la seva finalització) només al GP per constatar si s’han assolit els resultats previstos. Quan s’analitza l’evolució del GP s’observen millores en les habilitats d’autocontrol de les emocions, el reforç positiu i les relacions familiars. Tanmateix, des del punt de vista de les famílies no s’han observat canvis significatius en la millora de la percepció d’auto eficàcia del rol parental respecte el GC abans i després del programa. La percepció majoritària és que els objectius que planteja el programa són excessivament ambiciosos i en conseqüència, difícilment assolibles. Els responsables consideren que, en alguns casos, el perfil de famílies derivades al programa no és el més adequat perquè presenten problemàtiques molt més agudes a les desitjables per aquest tipus d’intervenció. Com a punts forts, es destaca que el programa és útil als ulls dels responsables i tècnics perquè genera una presa de consciència del problema i de la necessitat de canvi per part de les famílies. Els participants diuen transferir a la vida real algunes habilitats apreses especialment la comunicació i millora de les relacions familiars. Els tècnics aplicadors coincideixen amb la percepció de les famílies tot i declarar percentatges lleugerament inferiors. També és vist com un complement professional a la seva tasca que ajuda a fer un millor seguiment dels casos, i permet seguir treballant amb posterioritat amb les famílies.

Investigación evaluativa sobre el programa "LÍMITES"

Desde la comunidad científica se ha puesto de manifiesto la necesidad de evaluar los programas de intervención para la mejora de la parentalidad, especialmente en el contexto de la infancia y la adolescencia en riesgo. En esta investigación se presentan los resultados de la evaluación del programa Límites aportando evidencias de eficacia y efectividad, que permiten identificar y describir sus fortalezas, así como también aquellos elementos que pueden ser objeto de mejora. El programa Límites es una propuesta estructurada de intervención preventiva de carácter selectivo, con grupos de familias de jóvenes de entre 14 y 18 años que pasan por el circuito de la justicia juvenil. El programa ha estado funcionando desde 2007 en todo el territorio catalán, y ha incidido en un total de 351 personas y 245 familias. El programa consta de ocho sesiones en grupo en las que se trabajan contenidos relacionados con las relaciones y los vínculos, la comunicación, los conflictos, el establecimiento de normas y la disciplina. Para llevar a cabo la evaluación del programa Límites se ha partido de un diseño cuasi-experimental, pretest-postest aplicado a un grupo programa (GP) y grupo colaborador (GC) y de manera diferida (dos meses después de su finalización) sólo en el GP, para constatar si se han alcanzado los resultados previstos. Cuando se analiza la evolución del GP se observan mejoras en las habilidades de autocontrol de las emociones, el refuerzo positivo y las relaciones familiares. Sin embargo, desde el punto de vista de las familias no se han observado cambios significativos en la mejora de la percepción de auto eficacia del rol parental respecto al GC antes y después del programa. La percepción mayoritaria es que los objetivos que plantea el programa son excesivamente ambiciosos y en consecuencia, difícilmente alcanzables. Los responsables consideran que, en algunos casos, el perfil de familias derivadas al programa no es el más adecuado puesto que presenten problemáticas mucho más agudas a las deseables para este tipo de intervención. Como puntos fuertes, se destaca que el programa es útil a los ojos de los responsables y técnicos porque genera una toma de conciencia del problema y de la necesidad de cambio por parte de las familias. Los participantes dicen transferir a la vida real algunas habilidades aprendidas, especialmente la comunicación y mejora de las relaciones familiares. Los técnicos aplicadores coinciden con la percepción de las familias, a pesar de declarar porcentajes ligeramente inferiores. También es visto como un complemento profesional a su tarea que ayuda a hacer un mejor seguimiento de los casos, y permite seguir trabajando con posterioridad con las familias.