No description available.

The aim of this study is to examine which strategies three 18-year-old string students (one violinist and two cellists) use when they practice on their own. The empirical data for the study come from six observations of the students’ practicing on certain pieces that were handed out to them. During the observations, the students filmed themselves, and no one else was present in the room during the practicing sessions. The observations were later transcribed and analyzed, which means that its contents were compared and contrasted to results of previous research in the field of practicing. The results of this study show that all three participants first tried to gain an overview of the piece by playing it through from beginning to end. For the most part, the students played through longer parts of the music, but they also stopped to repeat single notes or half/whole bars. The students were also able to identify certain parts of the music that were more difficult. These parts received more work from the students and they repeated the difficult bars several times. What the students found difficult were for example fast passages, complicated rhythms, changing of position and intonation. The observations also show that only two of the students made musical interpretations while practicing. The students sometimes created their own exercises correlated to passages in the music that they practiced, which meant for example changing slurs or playing the melody together with an open string to sharpen the intonation.

Forskning har visat att beröm tenderar att ge negativa effekter på lärande och att det därmed inte leder eleven framåt i sin utveckling. Forskningen menar att beröm istället fungerar som en form av summativ bedömning. Mot denna bakgrund var mitt syfte att genom en kvalitativ studie, via lektionsobservationer och lärarintervjuer, undersöka hur idrottslärare använder feedback i sin undervisning och därmed i vilken form den uttrycks i och vilken funktion den har. Resultatet visade att lärarna använder beröm som den primära källan för feedback, med kommentarer som ”Bra!”, ”Bra jobbat!”, ”Härligt!” och ”Snyggt!”. Det är endast i dansundervisning eller i samband med skriftliga arbeten som lärarna ger feedback på andra nivåer, som syftar mot ett konkret lärande för eleven. Resultatet visar dessutom att ämnet idrott och hälsa tenderar att använda bedömning som en form av kunskapskontroll istället för formativ bedömning mot lärandemål, där eleverna ges möjligheter att utvecklas. Avslutningsvis kan sägas att studien belyser svaga länkar i idrottsundervisningen, som brister i bedömningen och huruvida lärarens feedback syftar mot fortsatt lärande eller inte.

I denna studie kommer vi att behandla begreppet bedömning för lärande. Syftet är att undersöka hur matematikläraren resonerar kring och arbetar med bedömning för lärande. Vi behandlar vad tidigare forskning har uppmärksammat om arbetet med bedömning för lärande. Lärarna som deltagit i studien via intervjuer åskådliggör att de medvetet försöker arbeta med bedömning för lärande för att främja sina elevers lärande. Arbetet med bedömning för lärande sker genom att tydliggöra målen för eleverna, ta hänsyn till elevernas tidigare kunskaper, samt feedback från lärare, kamrater och från eleverna själva. Lärarna upplever en positiv effekt på elevers lärande vid användandet av bedömning för lärande. De hinder vi uppfattar genom lärarna är att denna metod är tidskrävande, elevers tidigare erfarenheter av undervisning och att lärarna upplever bristfälliga kunskaper hos andra lärare av bedömning för lärande.

With the spread of latest state of the art technologies geared towards utilization of the human senses, haptic technologies have been introduced as a way of utilising the sense of touch to either solve real world problems or to enhance present experiences. This thesis focuses on using haptic technology in cars to make the driving experience safer. Modern vehicles carry GPS, music systems, sunroofs and a number of other electronic gadgets. Interaction with these devices while driving often takes the driver‘s eyes ―off the road‖ and raises safety concerns. We are proposing a unique haptic design that uses the ‗sense of touch‘ as a mode of controlling or coordinating the various technologies and convenience devices found within a car. A pattern of distinguishable haptic feedback linked to a corresponding device allows the user to operate these devices through ‗sense of touch‘ and eliminates reliance on visual interaction. This design will help to reduce the driver‘s distractions, as it will be installed in an easily accessible location such as on the steering wheel. A simulation has been done using a haptic interface ―i.e. desktop phantom to test the system‖ and a prototype has been developed which can be installed in any vehicle. This prototype has been tested to work with a limited number of convenient devices. However, further development and enhancements can be made to incorporate more devices and other user preferences. The main objective of this research is to integrate various functionalities in a robust manner, which will focus on the driver‘s safety by ensuring ―constant vision on the road‖. Distinguishable distinct haptic responses will act as unique depictions for specific convenient devices within the car, allowing the driver to interact and manipulate the settings of the device based on the detection and identification of the various unique haptic depictions. / UOIT

This thesis examines the challenges in creating a fully integrated optical receiver. Due to the nature of silicon, 850nm light exhibits a poor impulse response when directed at an on-die photodiode. Using a modified decision feedback equalizer with an infinite impulse response filter in the feedback path allows to eliminate the long tail of post-cursor ISI that is generated by the photodiode. Due to silicide depositions over the photodiodes, making them opaque, the receiver was tested using an electrical cable with similar frequency roll-off as that of a photodiode. A data rate of 3.7 Gbps was achieved and only limited by the amount of input reflections at the transimpedance amplifier. The receiver occupies an area of 0.23 mm^2 and consumes 51.3mW.

This thesis examines the challenges in creating a fully integrated optical receiver. Due to the nature of silicon, 850nm light exhibits a poor impulse response when directed at an on-die photodiode. Using a modified decision feedback equalizer with an infinite impulse response filter in the feedback path allows to eliminate the long tail of post-cursor ISI that is generated by the photodiode. Due to silicide depositions over the photodiodes, making them opaque, the receiver was tested using an electrical cable with similar frequency roll-off as that of a photodiode. A data rate of 3.7 Gbps was achieved and only limited by the amount of input reflections at the transimpedance amplifier. The receiver occupies an area of 0.23 mm^2 and consumes 51.3mW.

The English language could be considered to be a second language in Swedish society; it is present in more than just school, such as television, the world of computers and radio. The general field of interest for this study is an exchange between two schools, one located in Sweden and one in Italy, called the Da Vinci Project. The aim of the study is to get an insight into the effects on language development for the students participating in the project. The study focuses on exposure and error-feedback. The information was gathered using both interviews and questionnaires with students and teachers and I had the opportunity to visit the students when attending the school in Italy. Visiting the school in Italy made it easier to understand both the Italian and the Swedish students’ experience of a different school system than they were accustomed to. The results have been analyzed and it was possible to draw conclusions concerning the students’ language development as a result of meeting different teaching methods in the different school systems. The teachers’ answers provided important information about different teaching methods. Using theoretical approach to second language acquisition the results have been analyzed. Stephen Krashen’s monitor model has been an important component in analyzing the results. The results of the survey showed that the Da Vinci Project involves two totally different school systems using different methods when focusing on error-feedback and exposure. A “gap” was found between the two schools but the results of this survey show that for some students it has been their second language, English, has improved through the exchange. While a few students, in the Da Vinci Project, believe that they have not developed in their second language.

Grasping and functionally interacting with a relatively large or awkwardly shaped object requires the independent and cooperative coordination of both limbs. Acknowledging the vital role of visual information in successfully executing any prehensile movements, the present study aimed to clarify how well existing bimanual coordination models (Kelso et al, 1979; Marteniuk & Mackenzie, 1980) can account for bimanual prehension movements targeting a single end-point under varying visual conditions. We therefore, employed two experiments in which vision of the target object and limbs was available or unavailable during a bimanual movement in order to determine the affects of visual or memory-guided control (e.g. feedback vs. feed forward) on limb coordination.<p>Ten right-handed participants (mean age = 24.5) performed a specific bimanual prehension movement targeting a solitary, static object under both visual closed loop (CL) and open loop 2s delay (OL2) conditions. Target location was varied while target amplitude remained constant. Kinematic data (bimanual coupling variables) indicated that regardless of target location, participants employed one of two highly successful movement execution strategies depending on visual feedback availability. During visual (CL) conditions participants employed a dominant-hand initiation strategy characterized by a significantly faster right-hand (RH) reaction time and simultaneous hand contact with the target. In contrast, when no visual feedback was available (OL2), participants utilized a search and follow strategy characterized by limb coupling at movement onset and a reliance on the dominant RH to contact the target ~62 ms before the left.<p>In conclusion, the common goal parameters of targeting a single object with both hands are maintained and successfully achieved regardless of visual condition. Furthermore, independent programming of each limb is undeniably evident within the behaviours observed providing support for the neural cross-talk theory of bimanual coordination (Marteniuk & Mackenzie, 1980). Whether movement execution is visually (CL) or memory-guided (OL2) there is a clear preference of RH utilization possibly due to its dynamic and/or hemispheric advantages in controlling complex motor behaviours (Gonzalez et al., 2006). Therefore, we propose that bimanual grasping to a solitary target is possibly governed globally by a higher-level structure and successful execution is achieved via independent spinal pathway modulation of limbs.

Tot i la seva senzillesa, la idea de la realimentació negativa (o "feedback" en anglès) és extremadament poderosa i ha tingut un gran impacte en la societat des de la revolució industrial ençà. En l'actualitat, els sistemes de control estan a tot arreu. A la indústria de processos, per exemple, s'encarreguen de mantenir les variables d'interès aprop dels valors de consigna. Encara més, els sistemes de control han de garantir aquests objectius tot i la presència d'incertesa en el procés i l'existència de pertorbacions. En aquest sentit, la realimentació representa un mecanisme essencial alhora de millorar tant la qualitat com l'eficiència energètica en molts processos de fabricació. El tema cabdal d'aquesta tesi consisteix en el disseny analític de compensadors (també anomenats controladors) fent servir l'esquema convencial en realimentació unitària. El marc adoptat és del control lineal i invariant en el temps (LTI). Encara que la realitat és de naturalesa no lineal, la simplificació al cas lineal no suposa una restricció greu ja que, localment, sempre podem considerar l'aproximació lineal del procés sota control. Posteriorment, el rang d'operació del compensador es pot extendre fent servir algun procediment de control adaptatiu. Des del punt de vista del disseny del controlador, l'escenari considerat planteja, entre d’altres, dos compromisos fonamentals. D'una banda, el controlador haurà de sel·leccionar-se per tal d'assolir un bon balanç entre rendiment i robustesa de modelat. D'altra banda, existeix també un conflicte entre el rendiment tipus "regulatori" (rebuig de pertorbacions) i el rendiment tipus "servo" (seguiment de la consigna), essent de vegades convenient trobar-ne un equilibri entre aquests dos modes de funcionament. L'objectiu d'aquesta tesi és proporcionar procediments de disseny analítics basats en un model de la planta i els compromisos de robustesa/rendiment i servo/regulació. A diferència d'altres mètodes, els procediments presentats eximeixen el dissenyador d'haver de pensar pesos o models de referència adients. A més, els paràmetres de sintonia tenen un significat intuitiu per tal de simplificar l'ajustament dels paràmetres del controlador. Com que els controladors de tipus Proporcional-Integral-Derivatiu (PID) continuen sent els més emprats en la pràctica, s'ha considerat l'aplicació a aquest tipus particular de controlador. Per últim, val a dir que l'apropament analític d'aquesta tesi permet determinar, de manera explícita, com els diferents compromisos considerats afecten l'el·lecció final del controlador. Aquesta característica, creiem, és també valuosa des del punt de vista docent. / La idea de la realimentación negativa (o "feedback" en inglés), si bien sencilla, es extremadamente poderosa y ha tenido un gran impacto en la sociedad desde la revolución industrial. En la actualidad, los sistemas de control están en todas partes. En la industria de procesos, por ejemplo, son los encargados de mantener las variables de interés próximas a los valores de consigna, todo ello pese a la incerteza en el proceso y las perturbaciones externas. En este sentido, la realimentación es la única manera de estabilizar una planta inestable, y se presenta así como un mecanismo esencial en procesos de fabricación con el fin de mejorar la calidad del producto final y la eficiencia energética. El tema central de esta tesis es el diseño analítico de compensadores (también llamados controladores) en realimentación. El marco de control adoptado es del control lineal e invariante en el tiempo (LTI). Aunque la realidad raramente es de naturaleza lineal, la restricción al caso LTI obedece a su simplicidad y al hecho de que, localmente, es siempre posible aproximar un proceso no lineal por otro lineal. Desde este punto de vista, el rango de operación del compensador puede extenderse posteriormente mediante planificación de ganancia o control adaptable. Respecto a la configuración de control, esta tesis considera el esquema convencional en realimentación unitaria. En el escenario considerado, tenemos por un lado que el controlador debe diseñarse para proporcionar un buen compromiso entre el rendimiento y la robustez ante incerteza en el proceso. Por otro lado, también existe un conflicto entre el rendimiento tipo "servo" (seguimiento de la referencia o consigna) y el rendimiento tipo "regulatorio" (rechazo de las perturbaciones), siendo a veces deseable encontrar un equilibrio entre ambos modos de funcionamiento. El objetivo de esta tesis es proporcionar procedimientos de diseño analíticos basados en un modelo del proceso y los compromisos de robustez/rendimiento y servo/regulación. En los métodos propuestos no es necesario que el diseñador seleccione pesos o modelos de referencia como pasa con otros enfoques. Además, los parámetros de sintonía tienen un significado intuitivo con el fin de simplificar el ajuste de los parámetros del controlador. Debido a que los controladores de tipo Proporcional-Integral-Derivativo (PID) son ampliamente utilizados en la industria, se ha considerado la aplicación a este tipo de controladores. Por último, mencionar que el enfoque analítico de la tesis permite plasmar, de forma explícita, cómo los diferentes compromisos considerados influyen en la elección final del compensador. Esta característica es también valiosa desde el punto de vista de la docencia del control automático. / The concept of (negative) feedback, albeit simple, is extremely powerful, and has since the Industrial Revolution changed our world dramatically. Nowadays, control systems are everywhere. In process industry, for example, they keep the manipulated variables close to the set-points in spite of disturbances and changes in the plant. Moreover, feedback provides the only means to stabilize unstable processes. This way, the feedback mechanism reveals essential for improving product quality and energy efficiency, which yields better (sustainable) economy. The theme of this thesis is on analytical design of feedback compensators through linear control theory. The restriction to the Linear Time Invariant (LTI) case is not severe in the sense that most processes are well modeled locally by LTI systems. The operating range of the controller can then be extended using gain scheduling or adaptation. Within this work, the standard single-loop feedback configuration is assumed. Among the control objectives, stability and robustness are important considerations because of the presence of uncertainty in practice. Apart from that, the controller faces servo (set-point tracking) and regulation (disturbance rejection) objectives. In the considered scenario, it is well-known that there is an inherent compromise between robustness and performance. In general, the servo and regulation objectives are also conflicting and sometimes a balance is desirable. An example is in cascade configurations: the inner loop should be tuned based on tracking as it receives the set-points from the master loop. However, the inner loop may also need acceptable load disturbance suppression capabilities. Another good example is found in Model Predictive Control (MPC) applications due to frequent changes of set-points by the server. Finally, there may be a trade-off between the response to disturbances entering at the input and at the output of the plant, which can be understood as a servo/regulator trade-off too. The goal of this thesis is to provide model-based design procedures in terms of the Robustness/Performance and Servo/Regulator trade-offs, and give insight into how the tuning depends on the process parameters. In the presented methods, the designer is not required to choose weighting functions nor reference models as in other approaches, and the involved parameters have a clear meaning to facilitate the tuning process. Because PID controllers are prevalent in industry, application to PID tuning is considered most of the times. Although numerical methods for controller derivation may yield superior performance than analytical ones, the latter category has been preferred for several reasons. First, analytical procedures help understand the problem at hand. Second, when applied to low-order models, well-motivated tuning rules which are simple and easy to memorize can be obtained. These features are very desirable from the operator's point of view as well as for teaching purposes.