Análisis del entorno colaborativo creado para una experiencia de mobile learning

Se presentan los resultados de una investigación sobre las concepciones y usos de dispositivos móviles de un grupo de estudiantes que trabajaron en un entorno de aprendizaje colaborativo como parte un proceso de e-learning. Se emplearon dos métodos de investigación, en primer lugar el análisis del contenido de los mensajes de un foro de discusión enviados durante todo el curso, para recoger datos acerca del uso y la valoración que hacían del proceso de mobile learning. Posteriormente, mediante las entrevistas en profundidad, se analizó la percepción de mobile learning y los cambios producido durante el curso en el entorno colaborativo de aprendizaje. Los resultados indican que el entorno de intercambio creado amplifica la participación y colaboración entre los alumnos en el proceso de mobile learning, favoreciendo un mayor protagonismo de los estudiantes en una experiencia de aprendizaje online.

CHARACTERISING THE EOS SLOT-SCANNING SYSTEM WITH THE EFFECTIVE DETECTIVE QUANTUM EFFICIENCY.

NlmCategory="UNASSIGNED">As opposed to the standard detective quantum efficiency (DQE), effective DQE (eDQE) is a figure of merit that allows comparing the performances of imaging systems in the presence of scatter rejection devices. The geometry of the EOS™ slot-scanning system is such that the detector is self-collimated and rejects scattered radiation. In this study, the EOS system was characterised using the eDQE in imaging conditions similar to those used in clinical practice: with phantoms of different widths placed in the X-ray beam, for various incident air kerma and tube voltages corresponding to the phantom thickness. Scatter fractions in EOS images were extremely low, around 2 % for all configurations. Maximum eDQE values spanned 9-14.8 % for a large range of air kerma at the detector plane from 0.01 to 1.34 µGy. These figures were obtained with non-optimised EOS setting but still over-performed most of the maximum eDQEs recently assessed for various computed radiology and digital radiology systems with antiscatter grids.

Nota tècnica 1: projecte SETRAM

Un dels aspectes més crítics per assolir una definició avançada i realista del sistema SETRAM és la identificació de les tecnologies més adequades per a la localització d’usuaris mòbils, des de les ja existents (aplicables tant a la localització individual com agregada) fins a les més el.laborades per a la seva aplicació específica i exclusiva en aquest sistema.

An energy efficient vertical handover decision algorithm

As wireless communications evolve towards heterogeneousnetworks, mobile terminals have been enabled tohandover seamlessly from one network to another. At the sametime, the continuous increase in the terminal power consumptionhas resulted in an ever-decreasing battery lifetime. To that end,the network selection is expected to play a key role on howto minimize the energy consumption, and thus to extend theterminal lifetime. Hitherto, terminals select the network thatprovides the highest received power. However, it has been provedthat this solution does not provide the highest energy efficiency.Thus, this paper proposes an energy efficient vertical handoveralgorithm that selects the most energy efficient network thatminimizes the uplink power consumption. The performance of theproposed algorithm is evaluated through extensive simulationsand it is shown to achieve high energy efficiency gains comparedto the conventional approach.

Viestitaktiikan kehittyminen yhtymän viestijärjestelmän käyttöönoton jälkeen

Tutkimus käynnistyi Maanpuolustuskorkeakoulun taktiikan laitoksen esittäessä aihepiiriä tutkittavaksi. Tutkimuksen tavoitteena on ollut lisätä tietämystä viestitaktiikan kehittymisestä yhtymän viestijärjestelmän käyttöönoton jälkeen 1980 – 2000-luvuilla osana operatiivistaktisten toimintaperiaatteiden ja -tapojen kehittymistä. Tutkimuksella on pyritty syventämään tietämystä taktisten periaatteiden muutoksista viestitaktiikan näkökulmasta. Tutkimuksessa tarkasteltiin maavoimien YVI-järjestelmillä varustettujen yhtymien viestitaktiikkaa sekä niissä tapahtuneita muutoksia. Muutoksia tarkasteltaessa tutkimuksessa keskityttiin käsitykseen viestitaktiikasta, viestitaktisiin periaatteisiin sekä viestipäällikköön ja hänen toimintakenttäänsä. Viestitaktisia periaatteita ja niissä tapahtuneita muutoksia vertailtiin myös yleisiin taktisiin periaatteisiin ja niiden painotuksissa tapahtuneisiin muutoksiin. Tutkimus on luonteeltaan kvalitatiivinen. Tutkimusongelmia lähestyttiin fenomenografisella tutkimusotteella, jossa tavoitteena on kuvailla, analysoida ja ymmärtää erilaisia käsityksiä ilmiöistä sekä käsitysten keskinäisistä suhteista. Lähdeaineiston muodostivat 18 viestitaktiikan asiantuntijan kokemusperäiset käsitykset viestitaktiikasta ja sen kehittymisestä YVIjärjestelmien käyttöönoton jälkeen. Käsityksistä muodostettiin merkitys- ja kuvauskategorioiden sekä tutkijan esiymmärryksen pohjalta induktiivisen päättelyn avulla tutkimuksen varsinaiset johtopäätökset. Tutkimushenkilöiden käsitysten sekä taktiikan ja viestitaktiikan aikaisempien määritelmien perusteella johtopäätöksenä määritettiin, että viestitaktiikka on tehtävän toteuttamiseen käytettävissä olevan viestillisen kapasiteetin optimaalista suunnittelua, soveltamista ja käyttöä viestivoimana haluttujen päämäärien saavuttamiseksi ja viestitaisteluiden voittamiseksi. Viestitaktikointi edellyttää viestitaisteluun liittyvien keinojen tuntemista sekä taitoa soveltaa niitä käytännössä. Tutkimustulosten perusteella keskeisiksi viestitaktisiksi periaatteiksi tärkeysjärjestyksessä muodostuivat - päämäärän ja tehtävän selkeys - varautuminen odottamattomiin tilanteen vaihteluihin - yksinkertaisuus - aktiivisuus ja oma-aloitteisuus. Keskeisiksi merkitystään lisänneiksi viestitaktisiksi periaatteiksi muodostuivat - voimien vaikutuksen keskittäminen - joukkojen ja voimien jakaminen (reservi) - varautuminen odottamattomiin tilanteen vaihteluihin - salaaminen ja harhauttaminen - turvallisuus. Selkeimpänä viestipäällikön tehtävien muutoksena pidettiin siirtymistä yksityiskohtaisesta viestiyhteyksien suunnittelijasta kokonaisvaltaiseksi yhtymän viestitoiminnan johtajaksi. Tutkimustulosten ja aikaisempien määritelmien perusteella johtopäätöksenä määritettiin, että viestipäällikkö johtaa yhtymän viestitoimintaa komentajan antamien vaatimusten mukaisesti ja vastaa yhtymän johtoryhmän jäsenenä viestitaktisista ratkaisuista haluttujen päämäärien saavuttamiseksi ja viestitaisteluiden voittamiseksi. Viestipäälliköltä edellytetään viestitaisteluun liittyvien keinojen tuntemista sekä taitoa soveltaa niitä käytännössä. Tutkimuksen mukaan yhtymän viestitaktiikkaan merkittävimmin vaikuttaneita tekijöitä olivat yhtymän viestijärjestelmien käyttöönotto, uusien esikunta- ja viestiyksiköiden kehittäminen, kiinteän viestiverkon ja johtamisjärjestelmäalan merkityksen kasvaminen, käytettävien tekniikoiden kehittyminen sekä joukkojen ja johtoportaiden tiedonsiirtotarpeiden kasvaminen. Viestitaktiikan osalta voidaan todeta deterministisen näkemyksen taistelusta ja taistelutilasta muuttuneen yleisten taktisten periaatteiden muutosten mukaisesti aikaisempaa monimuotoisempaan ja rohkeampaan, voluntaarisempaan, suuntaan.

Summaries of lecture recordings used as learning material in blended learning

Julkaisumaa: 530 AN ANT Alankomaiden Antillit

A cyber security architecture for military networks using a cognitive network approach

Cyber security is one of the main topics that are discussed around the world today. The threat is real, and it is unlikely to diminish. People, business, governments, and even armed forces are networked in a way or another. Thus, the cyber threat is also facing military networking. On the other hand, the concept of Network Centric Warfare sets high requirements for military tactical data communications and security. A challenging networking environment and cyber threats force us to consider new approaches to build security on the military communication systems. The purpose of this thesis is to develop a cyber security architecture for military networks, and to evaluate the designed architecture. The architecture is described as a technical functionality. As a new approach, the thesis introduces Cognitive Networks (CN) which are a theoretical concept to build more intelligent, dynamic and even secure communication networks. The cognitive networks are capable of observe the networking environment, make decisions for optimal performance and adapt its system parameter according to the decisions. As a result, the thesis presents a five-layer cyber security architecture that consists of security elements controlled by a cognitive process. The proposed architecture includes the infrastructure, services and application layers that are managed and controlled by the cognitive and management layers. The architecture defines the tasks of the security elements at a functional level without introducing any new protocols or algorithms. For evaluating two separated method were used. The first method is based on the SABSA framework that uses a layered approach to analyze overall security of an organization. The second method was a scenario based method in which a risk severity level is calculated. The evaluation results show that the proposed architecture fulfills the security requirements at least at a high level. However, the evaluation of the proposed architecture proved to be very challenging. Thus, the evaluation results must be considered very critically. The thesis proves the cognitive networks are a promising approach, and they provide lots of benefits when designing a cyber security architecture for the tactical military networks. However, many implementation problems exist, and several details must be considered and studied during the future work.

Creating generation Y sources of motivation for enhanced performance

New challenges have been created in the modern work environment as the diversity of the workforce is greater than ever in terms of generations. There will become a large demand of generation Y employees as the baby boomer generation employees retire at an accelerated rate. The purpose of this study is to investigate Y generation specific characteristics and to identify motivational systems to enhance performance. The research questions are: 1. What are Y generation characteristics? 2. What motivational systems organizations can form to motivate Y generation employees and in turn, create better performance? The Y generation specific characteristics identified from the literature include; achievement oriented; confident; educated; multitasking; having a need for feedback; needing management support; sociable and tech savvy. The proposed motivational systems can be found in four areas of the organization; HRM, training and development, communication and decision making policies. Three focus groups were held to investigate what would motivate generation Y employees to achieve better performance. Two of these focus groups were Finnish natives and the third consisted of international students. The HRM systems included flexibility and a culture of fun. It was concluded that flexibility within the workplace and role was a great source of motivation. Culture of fun was not responded to as favorably although most focus group participants rated enjoyableness as one of their top motivating factors. Training and development systems include training programs and mentoring as sources of potential motivation. Training programs were viewed as a mode to gain a better position and were not necessarily seen as motivational systems. Mentoring programs were not concluded to have a significant effect on motivation. Communication systems included keeping up with technology, clarity and goals as well as feedback. Keeping up with technology was seen as an ineffective tool to motivate. Clarity and goal setting was seen as very important to be able to perform but not necessarily motivating. Feedback had a highly motivating effect on these focus groups. Decision making policies included collaboration and teamwork as well as ownership. Teams were familiar and meet the social needs of Y generation employees and are motivating. Ownership was equated with trust and responsibility and was highly valued as well as motivating to these focus group participants.

OpenAIRE Guidelines for Literature Repositories, Data Archives and CRIS managers

Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

Islandora Archipelago: Update on the Project & Community

Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

Axially Symmetric Radiation Patterns from Flanged E-Plane Sectoral Horn

A simple technique for obtaining identical E- and H-plane patterns from E-plane sectoral feed horn is presented. Halfpower beam width and gain of the antenna are also improved considerably. Experimental results for a number of horns with flanges of various parameters are also presented. This system may find practical application in radar and space communication systems

Dielectric Properties of Ba5Nb4O15 Ceramic

Ceramic dielectrics with high dielectric constant in the microwave frequency range are used as filters, oscillators [I], etc. in microwave integrated circuits (MICs) particularly in modern communication systems like cellular telephones and satellite communications. Such ceramics, known as 'dielectric resonators (DRs),donot only offer miniaturisation and reduce the weight of the microwave components. but also improve the efficiency of MICs

BROADBAND WIDE COVERAGE UNIPLANAR ANTENNA

The Present thesis deals with the numerical as well as experimental investigations conducted on the resonance and radiation characteristics of Drum shaped monopole antenna, Funnel shaped monopole antenna and the shorted coplanar antenna.An introduction to the over view of antennas, state of the art planar antenna technologies, different feeding techniques and introduction of coplanar waveguides have been discussed.

Investigations on broadband planar monopole and slot radiators and their suitability for UWB applications

In recent years, there is a visible trend for products/services which demand seamless integration of cellular networks, WLANs and WPANs. This is a strong indication for the inclusion of high speed short range wireless technology in future applications. In this context UWB radio has a significant role to play as an extension/complement to existing cellular/access technology. In the present work, we have investigated two major types of wide band planar antennas: Monopole and Slot. Four novel compact broadband antennas, suitable for poratble applications, are designed and characterized, namely 1. Elliptical monopole 2. Inverted cone monopole 3. Koch fractal slot 4. Wide band slot The performance of these designs have been studied using standard simulation tools used in industry/academia and they have been experimentally verified. Antenna design guidelines are also deduced by accounting the resonances in each structure. In addition to having compact sized, high efficiency and broad bandwidth antennas, one of the major criterion in the design of impulse-UWB systems have been the transmission of narrow band pulses with minimum distortion. The key challenge is not only to design a broad band antenna with constant and stable gain but to maintain a flat group delay or linear phase response in the frequency domain or excellent transient response in time domain. One of the major contributions of the thesis lies in the analysis of the frequency and time-domain response of the designed UWB antennas to confirm their suitability for portable pulsed-UWB systems. Techniques to avoid narrowband interference by engraving narrow slot resonators on the antenna is also proposed and their effect on a nano-second pulse have been investigated.

Impact of Self-generation of Priorities and Non-preemptive Service in Single/Multiserver Queues

In this thesis we have studied a few models involving self-generation of priorities. Priority queues have been extensively discussed in literature. However, these are situations involving priority assigned to (or possessed by) customers at the time of their arrival. Nevertheless, customers generating into priority is a common phenomena. Such situations especially arise at a physicians clinic, aircrafts hovering over airport running out of fuel but waiting for clearance to land and in several communication systems. Quantification of these are very little seen in literature except for those cited in some of the work indicated in the introduction. Our attempt is to quantify a few of such problems. In doing so, we have also generalized the classical priority queues by introducing priority generation ( going to higher priorities and during waiting). Systematically we have proceeded from single server queue to multi server queue. We also introduced customers with repeated attempts (retrial) generating priorities. All models that were analyzed in this thesis involve nonpreemptive service. Since the models are not analytically tractable, a large number of numerical illustrations were produced in each chapter to get a feel about the working of the systems.