Aquesta recerca desenvolupa una ampliació de la metodologia de sistemes consistents de clústers que la fan aplicable a una realitat de gran complexitat: la relació entre perfils de consulta dels materials d'un campus virtual i els rendiments acadèmics. L'assignatura a la que s'aplica la metodologia és la de Bases de dades dels estudis d'enginyeria de l'Escola Tècnica Superior d’Enginyeria Electrònica i Informàtica de La Salle‐URL. Aquesta assignatura és molt heterogènia en continguts i competències, per la qual cosa té un flux d'avaluació complicat. Per assignar la nota final a un alumne es combinen proves de coneixement algorítmic, pràctiques, treballs o documentació sobre aspectes específics de la matèria. A més, el centre ofereix la possibilitat als alumnes que es recuperin d'ensopegades puntuals en la diversitat d'exàmens o exercicis que han de realitzar, ja que els permet presentar‐se a recuperacions en diferents moments del curs. Per aquest motiu, es desenvolupa la metodologia dels sistemes consistents de clústers de manera heurística cercant de trobar informació rellevant. L'aplicació de la metodologia requereix d'un procediment de ‘trial and error’ fins trobar models que encaixin satisfactòriament amb la realitat estudiada. El text que s'ha publicat finalment omet moltes proves i cerques, ja que es van explorar diversos camins d'anàlisi estadística abans d'arribar a un conjunt raonable i homogeni de tècniques amb resultats positius. L'aproximació dels sistemes consistents de clústers tan sols havia estat definida en la tesi precedent de Senmartí (2010), com a alternativa a estudis correlacionals o factorials, però feia falta considerar una ampliació de les idees exposades. En aquesta investigació s’hi introdueixen variacions, de manera que la fan susceptible de ser aplicada a situacions més complexes que es tracten mitjançant dissenys expostfacto. De les conclusions acadèmiques en destaquem dues aportacions: a) El concepte de clúster diana, que neix de manera natural dels sistemes consistents de clústers aplicats a aquest tipus de recerca sobre rendiment acadèmic (susceptible també de ser aplicat en investigacions de qualsevol tipus on es disposi d'una variable d'interès, ja sigui “benefici”, “vendes”, “malalts que milloren”, etc.) b) Les directrius per a la docència en la formació superior que sorgirien del model d'ajust aconseguit. Especialment el descobriment que els estudiants amb millor rendiment acadèmic solen trobar‐se més en clústers de perfil selectiu en les consultes que no pas en clústers de perfil exhaustiu. El sistema consistent de clústers fa palesa la “cultura de consulta” als campus virtuals que desenvolupen els estudiants. / La presente investigación desarrolla una ampliación a la metodología de sistemas consistentes de clústers que la hacen aplicable a una realidad sumamente compleja: la relación entre perfiles de consulta de los materiales de un campus virtual y los rendimientos académicos. La asignatura a la que se aplica la metodología es la de Bases de Datos de los estudios de ingeniería de la Escola Tècnica Superior d’Enginyeria Electrònica i Informàtica La Salle ‐URL. Esa asignatura es muy heterogénea en contenidos y competencias, por lo que tiene un flujo de evaluación complicado. Para asignar la nota final a un alumno se combinan pruebas de conocimiento algorítmico, prácticas, trabajos o documentación sobre aspectos específicos de la materia. Además, el centro ofrece la posibilidad a los alumnos de que se recuperen de tropiezos puntuales en la diversidad de exámenes o ejercicios que deben realizar, ya que les permite presentarse a recuperaciones en diferentes momentos del curso. Por tal motivo, se desarrolla la metodología de los sistemas consistentes de clústers de manera heurística en búsqueda de información relevante. La aplicación de la metodología requiere de un procedimiento de trial and error hasta encontrar modelos que encajen satisfactoriamente con la realidad estudiada. El texto que se ha publicado finalmente omite muchas pruebas e intentonas, ya que se pusieron en práctica muchos otros caminos de análisis estadístico antes de llegar a un conjunto razonable y homogéneo de técnicas con resultados positivos. La aproximación de los sistemas consistentes de clústers tan solo había sido definida en la tesis precedente de Senmartí (2010), como alternativa a estudios correlacionales o factoriales, pero hacía falta considerar una ampliación de las ideas expuestas. En esta investigación se realizan variaciones en la misma, de manera que la hacen susceptible de ser aplicada a situaciones más complejas que se tratan mediante diseños expostfacto. De las conclusiones académicas resaltamos dos aportaciones: a) El concepto de clúster diana, que nace de manera natural de los sistemas consistentes de clústers aplicados a este tipo de investigaciones sobre rendimiento académico (susceptible también de ser aplicado en investigaciones de cualquier tipo donde se disponga de una variable de interés, ya sea “beneficio”, “ventas”, “enfermos que mejoran”, etc.) b) Las directrices para la docencia en la formación superior que emanan del modelo de ajuste conseguido. En especial el descubrimiento de que los estudiantes con mejor rendimiento académico suelen encontrarse más en clústers de perfil selectivo en las consultas y no, en cambio, en clústers de perfil exhaustivo. El sistema consistente de clústers retrata la “cultura de consulta” en los campus virtuales que desarrollan los estudiantes. / This research develops an extension to the methodology of clusters that make it applicable to a very complex reality: the relationship between query profiles of materials of a virtual campus and academic performance. We applied this methodology in the learnings of Database of engineering studies Higher Technical School of Electronics and Computer d'Enginyeria La Salle ‐URL. This subject is very heterogeneous in content and skills, so it has a complicated evaluation flow which combines algorithmic knowledge tests, practical work or documentation on specific aspects of the subject in order to assign the final grade to a student. The school also offers the chance for students to recover from setbacks in the diversity of specific tests or exercises to be performed, allowing them to present to recoveries at different times of course. Therefore, we have developed a heuristically methodology of "Systems consisting of clusters" by searching for relevant information. The application of the methodology requires a process of trial and error to find models that fit satisfactorily with the reality studied. The thesis text finally published omits many prior attempts before reaching a reasonable and uniform set of techniques with positive results. The approach of "Systems consisting of clusters" had been defined only in the preceding Senmartí thesis (2010) as an alternative to correlational studies or factorial, but needed to consider an extension of the ideas. Our research made variations on it, so that it is capable of being applied to more complex situations that are treated by expostfacto designs. We underline two significant contributions: a) The concept of target cluster, which comes naturally to systems consisting of clusters applied to this type of research on academic performance (which can also be applied in investigations of any kind which have a variable interest i.e. "benefit "," sales ","patients who recover", etc.). b) The guidelines for teaching in higher education coming from the model fit achieved. In particular the finding those students with higher academic performance are more commonly found in clusters of selective queries profile instead of clusters of a comprehensive profile. The system of clusters shows the "culture of consultation" in a virtual campus that students develop.

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As background for this study stands the debate and discussion in the society around the tablet as a pedagogical tool in preschool. The purpose of this study is to obtain and analyze 69 preschool teachers’ opinions about the tablet’s introduction and use in preschool. The study also investigates the preschool teachers’ opinions about their mission for multimedia and technology in the preschool curriculum, Lpfö 98, reviderad 2010. The study is executed in the form of a survey. Questions at issue: How experienced are preschool teachers with the tablet? What is the preschool teachers’ opinion about the tablets usability and function in preschool? How important is multimedia tools such as tablets in preschool in the preschool teachers’ view? Which view do preschool teachers have on their own role and mission to offer and encourage children to explore and use contemporary technology? My analysis of the survey result shows that preschool teachers have basic level knowledge of the tablet and the technology. The preschool teachers’ experience in using tablets varies from no use to daily usage. The majority of the preschool teachers do not use tablets at home or at work. In spite of this, the preschool teachers are mainly positive about tablet usability in preschool. Most of the preschool teachers consider the tablet as having a wide range of usability or as being useful in pedagogical situations in preschool. Many of the preschool teachers believe it is important or rather important that technology such as the tablet is prioritized as a pedagogical tool in preschool. Most of the preschool teachers consider the aims and objectives in Lpfö 98, reviderad 2010 to be both satisfactory and challenging. From the survey it appears, for example, that preschool teachers think it is important for the preschool and the preschool teachers to develop in line with society. The preschool teachers also mention it is important to offer every child an opportunity to explore and use contemporary technology. Additionally, the preschool teachers mention that financial means as well as further education is needed to help increase their possibilities of fulfilling the aims and objectives in the curriculum. / Som bakgrund till denna undersökning ligger den rådande debatten i samhället om surfplattan som ett pedagogiskt multimedialt redskap. Syftet med studien är att undersöka vilka åsikter och meningar som råder hos 69 förskolepedagoger kring surfplattans introduktion och användning i förskolans verksamhet. I studien undersöks även hur pedagogerna ser på sin egen roll i relation till strävansmålen för multimedia och teknik i Lpfö 98, reviderad 2010. Undersökningen genomfördes genom en enkätundersökning. Frågeställningarna i studien: Hur stor erfarenhet har pedagogerna av surfplattor? Hur stort användningsområde anser pedagogerna att surfplattan har? Hur viktigt anser pedagogerna att det är med multimediala verktyg som exempelvis surfplattor i förskolan? Hur ser pedagogerna på sin egen roll att erbjuda och låta barnen tillägna sig ny teknik som exempelvis surfplattan? I studien framkommer det att samtliga pedagoger säger sig veta vad en surfplatta är. Deras egen erfarenhet är mycket varierad. Majoriteten av pedagogerna använder inte surfplatta varken hemma eller på arbetet. Trots det är pedagogerna sammantaget positivt inställda till surfplattans användbarhet i förskolans verksamhet. Flertalet pedagoger anser att surfplattan har stort användningsområde eller är användbart. En stor andel av pedagogerna anser att det är viktigt eller ganska viktigt att prioritera multimediala verktyg som exempelvis surfplattan till förskolebarn. Merparten av pedagogerna anser att strävansmålen i Lpfö 98, reviderad 2010, är bra och utmanande. Pedagogerna uppger bl.a. att det är viktigt att förskolan och pedagogerna arbetar för att följa med i samhällets utveckling samt att pedagogerna arbetar för att alla barn får möta den nya tekniken i förskolan. Pedagogerna tar även upp att ekonomiska medel samt fortbildning behövs för att öka möjligheterna till att uppfylla strävansmålen.

In der Stadtbibliothek Kamenz hören sich Kinder seit Januar 2012 mit TING schlau. Der Stift, eine Kombination aus Lesegerät und mp3-Player, gibt gedruckten Medien eine neue Dimension. Kaum größer als ein Kugelschreiber macht er Buchseiten hörbar (TING = chinesisch Hören).

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Multimedia' nature of an application refers to the presence of several media streams in parallel. Whether it is receiving real-time data or retrieving stored data, there exists an end-to-end delay in data transfer from source to destination over the network. This delay experienced can be split into a fixed part and a variable part. Data processing time like coding and decoding at the source and destination are the fixed delays experienced. The variable delay occurs mainly due to queuing at the intermediate nodes during its flow through the network. The variable or unequal delays introduce gaps or discontinuities within a stream. In multi-stream applications where each stream may flow on different routes based on the bandwidth availability experiencing different delays, mismatch between them can also occur. These discontinuities and skews result in poor quality of playout. Clock drift and variations in drift rates between the source/s and destination/s, clock also lead to poor quality of play out. To eliminate these skews and discontinuities, there must be mechanisms, viz., and synchronisation services to convey, reintroduce and maintain the temporal relationship between the media streams for presentation throughout the playout, at the destination. The reintroduction of this lost temporal relationship within a stream and between various media streams for presentation at the destination is the object of multimedia synchronisation and is the subject matter of this thesis. In the presence of synchronised clocks, the main cause of asynchronies between media streams is the difference in delays experienced and the jitter. In this work, to convey the temporal relationship between streams of an application to the playout site, each stream is assigned a priority л, based on its importance to the user. The media streams are then divided into synchronisation units called 'Groups' based on that stream's characteristics which has the highest priority л. A group may therefore consist of one video frame and other data which were generated in that interval. Or may consist of silence and talk-spurt periods of the voice stream with data units of other streams generated in the same interval. Since the quality of playout of temporally related delay-sensitive streams depends upon the delay-experienced, the concept of QoS can be extended to describe the presentation requirements of uch data. Depending on the user perception and the delay experienced, an application can have a range of playout times, giving the best performance. The presentation of many real-time applications can be considered satisfactory even when the delay bound is exceeded by a small amount for a short period of time under varying network conditions. This property can be exploited by defining two sets of QoS parameters, namely QoS optimum and QoSlimit for each real-time application. As the delay and its variations increase, the optimum playout time range decreases. QoS optimum specifies the performance parameters required to perceive 'realtime'. Multimedia data can be played out at its QoSlimit with a deterioration in quality under poor network conditions still maintaining the synchronisation between streams. To control the playout at two levels of QoS, and maintain intra-media and inter-media synchronisation, stream controllers and super stream controllers have been used. The dynamic delay compensation algorithm and synchronisation services were simulated using network delay models and performances studied. It is shown that the proposed algorithm not only synchronised media streams and smoothened jitter but also optimised buffer space and buffer occupancy time while meeting the desired quality of service requirements

The rapid growth in multimedia based Internet systems and applications like video telephony, video on demand, network based DVD recorders and IP television has created a substantial need for multimedia security. One of the important requirements for multimedia security is transmission of the digital multimedia content in a secure manner using encryption for protecting it from eavesdropping. The simplest way of encrypting multimedia content is to consider the two-dimensional/three-dimensional image/video stream as an one-dimensional stream and to encrypt the entire content using standard block ciphers like AES, DES, IDEA or RC4 or using a stream cipher. The method of encrypting the entire multimedia content is considered as a naive encryption approach. Even though the naive encryption approach provides the desired security requirements, it imposes a large overhead on the multimedia codex. This is due to the size of the multimedia content, and also due to real time requirements of transmission and rendering. Hence, lightweight encryption schemes are gaining popularity for multimedia encryption. Lightweight Encryption schemes are based on the principle “Encrypt minimal and induce maximum noise". Lightweight encryption schemes are designed to take the structure of the multimedia content into consideration. In our work we analyze some of the existing lightweight encryption schemes for digital images and video. The analysis is done based on the amount of security, scalability and effect on compression. A detailed study of some of the existing lightweight encryption schemes is also done by designing cryptanalysis schemes. The cryptanalysis schemes are designed using image noise clearing algorithms and pixel prediction techniques. The designed cryptanalysis schemes reduce the amount of noise introduced by the corresponding lightweight encryption schemes considerably. Based on our analysis of existing lightweight encryption schemes, we propose a set of more robust lightweight encryption schemes for images and video. The proposed lightweight encryption schemes are secure, scalable, and do not degrade the compression achieved. In our work, we also propose a few enhancements to JPEG image compression for achieving more compression, without compromising on the quality. The enhancements to the JPEG compression are extensions of the pixel prediction techniques used in the proposed cryptanalysis schemes.

Syftet med vår studie är att undersöka hur lärare i årskurs ett till tre använder sig av multimediala verktyg för att främja elevernas språkutveckling. Vi vill också få kännedom om varför de använder sig av multimedia samt deras attityder till användandet. Våra frågeställningar är följande:  Vilken syn har läarna påmultimediala verktyg fö språutveckling?  Hur anväder läarna multimediala verktyg fö att fräja elevernas språutveckling? Vi har använt oss av en kvalitativ metod i form av intervjuer i vår studie. Detta metodval gjorde vi för att få en djupare uppfattning om lärarnas användande och attityder till multimediala verktyg. Den sociokulturella teorin ligger till grund för vår uppsats, även literacy är en teori som vi utgår ifrån i vår studie. Vi beskriver också Gardners teori. Resultatet visar att samtliga lärare var positiva till att använda multimediala verktyg i undervisningen. Alla betonade vikten av mer utbildning om de tekniska verktygen. Det framgick att de vanligaste multimediala verktygen som användes var Activeboard och dator. Vi drar slutsatsen att lärarna inte aktivt använder de multimediala verktygen för att främja språkutveckling. / The aim of our study is to examine how teachers in grade one to three use digital tools to promote students' language development. We also want to know why they make use of multimedia and their attitudes to using. Our questions are:  What do teachers think about digital tools for language development?  How do teachers use digital tools to promote language development? We have used a qualitative approach through interviews in our study. This methodological choice we made in order to gain a deeper understanding of teachers' use and attitudes towards digital tools. The sociocultural theory is the basis for our study, while literacy is a theory that we assume in our study. We also describe Gardner’s theory. The results show that all teachers were positive about using digital tools in teaching. All stressed the importance of more education on the technical tools. It appeared that the most common digital tools used was the Active Board and the computer. We conclude that teachers do not actively use digital tools to promote language development.

Den här doktorsavhandlingen presenterar ytinteraktion som ett gränssnitts-paradigm för grafiska användargränssnitt inom kreativa tillämpningar. Ytinteraktion utgår ifrån användarnas innehåll och allt innehåll presenteras på en oändligt stor tvådimensionell yta. Ytan är gränssnittet mot en databas som navigeras och zoom, pan och textfilter. Textfilter används för att visa vilka innehållselement som motsvarar en textsträng, ju fler tecken i strängen, desto färre motsvarande element. Ytinteraktion gör att användare kan dela och redigera innehåll tillsammans via synkront samarbete.Ytinteraktion har studerats genom att utveckla en interaktiv prototyp för kollaborativ live multimedia. Prototypen designades tillsammans med musik- och videoartister inom electronica- och klubbmusikgenren. Den kan användas med pekskärm eller med skäm, mus och tangentbord. Design-processens resultat utvärderades genom en fallstudie som omfattade artisternas förberedelse inför och genomförandet av ett framträdande vid en festival. Analysen av data resulterade i fem bruksvärden; instrumentvärde, kommunikationsvärde, förberedelsevärde, livevärde och underhållningsvärde. Det huvudsakliga bruksvärdet var att den interaktiva prototypen uppfattades som ett instrument. Prototypens design underlättade kommunikationen mellan artisterna i flykten på scen. Instrumentvärdet gjorde det lättare att spela live vilket i sin tur medförde att publiken blev underhållen. Kunskap om den interaktiva prototypen och ytinteraktion har formats med forskning genom design där aktionsforskning var det övergripande ramverket i forskningsprocessen. Aktionsforskning är ett kvalitativ förhållningssätt som sätter fokus på praktikers deltagande i forskningsprocessen och att forskningen intervenerar i praktiken med syfte att förbättra den och att inducera kunskap. Som ett resultat av designprocessen presenteras designprinciper för ytinteraktion. Dessa gör resultaten användbara för praktiker inom interaktionsdesign, människa–datorinteraktion och programvaruteknik. / This dissertation presents surface interaction as an interface paradigm for graphical user interfaces of creative applications. The users' content is the basis for surface interaction, and all content is presented on an infinitely large two-dimensional surface. The surface is an interface to a database, and is navigated by zoom, pan, and text filter. Text filter is to display which content elements match a text string, the more characters of the string the less matching element. Surface interaction allows users to share and edit content collaboratively via synchronous collaboration. Surface interaction was examined by developing an interactive prototype for collaborative live multimedia. The prototype was designed in collaboration with music and video artists within the genres of electronica and club music. It can be used either with a touch screen or with a monitor, mouse, and keyboard. The result of the design process was evaluated in a case study which included the artists' preparations for and carrying through of  a live performance at a festival. The analysis of data yielded five utility values; instrument value, communication value, preparation value, live value, and entertainment value. The main utility value of the interactive prototype was that the artists saw it as instrument.  The design of the prototype made communication easier in the live situation on stage. The instrument value made it easier to play live which consequently entertained the audience.Cognition in the interactive prototype and surface interaction has been created with research through design where action research was the overarching framework. Action research is a qualitative method  which focuses on the participating practitioners and on the intervention of the practice with the purpose improving the practitioner’s situation and of increasing the knowledge of the participants. Design principals and guidelines will be presented as a result of the design process. The guidelines make the results of this dissertation applicable to practitioners of interaction design, human computer interaction and software engineering.

Zugl.: Trier, Universiẗat, Diss., 2007. / Hergestellt on demand.