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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Age Differences in Revision of Causal Belief

Simmons, Kristi M. 01 December 2011 (has links)
Inductive reasoning (IR) requires efficient working memory (WM). Research shows that the prefrontal cortex (PFC) is involved during WM tasks and that PFC functioning declines with age. The ability to comprehend and update text-based information requires an intact PFC and efficient WM and IR. The current study presented a series of messages about the investigation of a warehouse fire to 48 young and 48 older adults. One message contained a piece of misinformation which another message corrected later. It was hypothesized that a memory cue to the misinformation with the correction statement should benefit older adults the most during the updating process. A text-based level and situation model level measured updating. The text-based level is only information from the text but is not necessarily verbatim. The situation model level is the overall meaning of the text, including inferences and assumptions. Results show that unlike young adults, older adults are not capable of recalling the text at the text-based level. However, older adults are capable of performing like young adults at the situation model level. This suggests that older adults are capable of updating causal information in text material as long as a memory cue to the misinformation is provided within the correction statement.
112

Inductive Pulse Generation

Lindblom, Adam January 2006 (has links)
Pulsed power generators are a key component in compact systems for generation of high-power microwaves (HPM). HPM generation by virtual cathode devices such as Vircators put high demands on the source. The rise time and the pulse length of the source voltage are two key issues in the generation of HPM radiation. This thesis describes the construction and tests of several inductive high power pulse generators. The pulse generators were designed with the intent to deliver a pulse with fast rise time and rectangular voltage. Therefore, the pulse generators are all based on discharges of transmission lines. The transmission lines used in the pulse generators are modern high voltage cables normally used in power transmission. All tested pulse generators have step up transformers as intermediate magnetic energy storage. Further, the pulse generators have contributed to the knowledge of compact designs. Closing switches is another important device in pulse generator architectures. In general, high power switching involving large currents and high voltages requires the use of robust switches. The switches used in the pulse generators of this thesis are of gas and liquid type.
113

A Higher-Order Knuth-Bendix Procedure and Its Applications

CHIBA, Yuki, KUSAKARI, Keiichirou 01 April 2007 (has links)
No description available.
114

Chinese Consumer Behavior in the Mobile Phone Market : Nokia Case

Zhou, Na, Shanturkovska, Gergana January 2011 (has links)
To become successful in China is a challenge not every international company can cope with. The competition is cruel as everyone struggle for a larger piece of share. Some manage to find the “secret” formula, others simply are left behind. Still, the market is too big to be neglected and extremely unpredictable to be easily handled. Nokia has proved to be foreseeing and wise enough to not only enter that market, but also climb up the ladder of success and stay there for a decade. This work aims to give a clear and thorough picture of Nokia’s successful strategy in penetrating the Chinese market. It follows and explains the steps Nokia took back in the days in building strong brand awareness and thousands of loyal customers in the face of the Chinese consumer. Its purpose is not only to tell the story of success, but also to teach important lesson future investors and perhaps give a precious insight into the topic. The Chinese market needs to be studied and analyzed as well in order to build a better understanding for it. We need to find out how they feel, what they think and what factors influence their behavior and finally how to approach them. A series of different research methods like secondary data, personal and group interviews, and online survey will be used here. The approach in this study will be inductive, where specific theory will be developed based on research.
115

Design and Evaluation of a Transcutaneous Energy Transfer System

Bossetti, Chad A January 2009 (has links)
<p>A clinically viable brain-machine interface (BMI) requires a fully-implanted wireless neural acquisition system to limit the impediments of percutaneous connections. For an implanted system with an appreciable telemetry range, and where significant</p><p>neural signal processing is performed continuously, a major obstacle for clinical application is the need for a power source. Existing battery technology and wireless power delivery systems have not addressed the need for a mid-range power supply, capable</p><p>of 1-3 W delivery, that limits both induced noise and temperature rise. These factors are crucial for the succesful operation of a fully-implanted neural acquisition system. This work seeks to fill this void, and presents both a wireless power solution suitable for a neural recording device, and a system capable of real time monitoring of tissue temperature rise.</p><p>During this research, a 2 W transcutaneous energy transfer system (TETS) was designed, built and tested. The TETS was designed specifically for a 96-channel implanted neural data acquisition system, which requires continuous power. The major design constraints were tolerance to coil misalignment, low induced noise,</p><p>and reasonable efficiency. The design of the primary circuit consists of an H-bridge switching network driving a planar spiral Litz wire primary coil. The primary also incoporates a novel circuit for detecting the presence of the secondary. The implanted secondary components include a complimentary planar spiral coil connected to a voltage doubling rectifier. The key approach to mitigating axial coil misalignments was the use of step-down switching regulators in the secondary. With this approach, link efficiency remained nearly constant at 40%, for axial coil displacements of up to 2 cm.</p><p>Noise in the recorded neural signals was minimized using two techniques. First, the 250 kHz operating frequency of the system was tuned, such that the aliased harmonics of the switching frequency lay above the bandwidth of the amplifier used for neural recording. The second approach was to limit the impact of induced displacement currents in the body by physically separating the recording front end from the power supply components. A large titanium enclosure was used to house some of the secondary electronics, and provided a low impedance return path for further</p><p>reduction of current-induced noise.</p><p>Limiting the temperature rise of internal components was also a critical design constraint. The need for real time temperature information led to the design of a six channel temperature measurement system and incorporation of the temperature data into the acquisition system data transmission scheme. This system consisted of bead thermistor temperature transducers, and an off-the-shelf microcontroller with a built-in instrumentation amplifier.</p><p>The TETS and temperature system was fully tested in an ovine model during several acute studies. Recorded temperature rise was limited to approximately 5.5&deg C when the system was implanted at an adequate depth in muscle. The TETS was able to successfully power the 2 W neural acquisition system during a data processing task. Received rectified voltage in the secondary ranged from 14.86 V to 20.2 V, while link efficiency remained virtually constant. Acquired neural data was examined for TETS switching noise. The measured RMS noise increased by less than 1 &mu V, averaged over several experiments. These results demonstrate the first mid-range TETS solution for powering a fully implanted neural acquisition system.</p> / Dissertation
116

Are Respiratory Behaviors Affected in Individuals With Adductor Spasmodic Dysphonia?

Biedess, Katie 01 June 2006 (has links)
Adductor spasmodic dysphonia (ADSD) is a focal dystonia that is characterized by voice breaks due to involuntary contractions of the adductor muscles of the vocal folds. These spasms can interfere with the coordination and balance of the respiratory and phonatory systems interfering with normal voice production. Disruptions in normal respiratory behaviors are well documented in inviduals with laryngeal disorders, including ADSD. Previous research regarding respiratory processes in ADSD has focused on airflow and pressure; however, there are many other parameters that have not been considered and may shed new light on the respiratory behaviors of individuals with ADSD. Therefore, the current pilot study attempted to determine if individuals with ADSD differed from controls in various breathing parameters while engaged in conversational and reading tasks.Thirty individuals were tested; fifteen in the ADSD group and fifteen in the age- and gender-matched control group. Respitrace, an inductive plethysmography device, calculated 14 different respiratory measures related to volume, timing, thoracic displacement and respiratory efficiency. The results of the study indicated that various significant differences existed between groups. Those with ADSD were found to have statistically higher ventilation rates, a greater frequency of breaths per minute, a higher degree of muscular inefficiency/breathlessness and labored breathing. These results indicated that individuals with ADSD suffered from disordered breathing due to the neurologically related obstruction at the level of the larynx. Differences according to task were also found. Specifically, the rib cage contributed to a lesser extent in voice production and the participants utilized longer inspiratory times, exhaled a larger volume of air and took longer to reach peak expiratory flow during conversational tasks when compared to reading tasks. These differences were attributed to a higher cognitive-linguistic demand required during conversational speech. Overall, the results of this study have many clinical implications. Most importantly, these findings support the idea that individuals with ADSD may experience difficulties with respiration as the effects of their Botox injection begin to wear off. Further research is needed with regards to the effects laryngeal spasms have on other respiratory behaviors.
117

Utveckling av mottagare för induktiv laddning / Development of Wireless Charging Receiver

Johansson, Dennis January 2015 (has links)
Detta examensarbete handlar om trådlös batteriladdning. Arbetet har utförts genom Jörgensen Industrielektronik AB, ett företag som specialiserat sig på kundanpassade elektroniklösningar. Företaget utvecklade en ny produkt, där det skulle finnas som tillval att den kunde laddas trådlöst. En mottagare för trådlös laddning av produktens batterier utvecklades. Mottagaren utvecklades utifrån Qi-standarden som beskrivs i denna rapport. Mottagarens elektriska egenskaper bestämdes (t.ex. effektivitet och laddström). EMCtester av mottagaren utfördes för att undersöka hur mycket störningar mottagaren genererade. Arbetet resulterade i en mottagare som kunde ladda produktens batterier med en befintlig Qi-laddstation. Effektiviteten hamnade på en nivå som är vanlig för trådlös laddning, jämfört med ledningsbunden laddning så var effektiviteten lägre. Resultatet av EMCtesterna visade att mottagaren genererade elektromagnetiska störningar, men emissionsnivåerna var inom gränserna för de EMC-standarder mätningarna har jämförts med. / The subject of this thesis is wireless battery charging. The thesis has been made in collaboration with Jörgensen Industrielektronik Ltd, specialized in costumer adapted electronics. The company developed a new product, where wireless charging was an optional feature. In this thesis a wireless charging receiver was developed. The receiver was intended for charging the batteries in the product. The receiver was developed according to the Qi standard. The Qi standard is described in this report. EMC tests were performed on the receiver in order to examine the levels of emissions radiated. The work resulted in a receiver that was able to charge the product's batteries with an existing Qi charging station. The efficiency was normal for wireless charging, compared to wired charging the efficiency was lower. The EMC tests showed that the receiver radiates electromagnetic energy. The radiated emissions were within the limits of the EMC standards that the measurements have been tested against.
118

Using the Dictogloss in the high school foreign language classroom : noticing and learning new grammar

Hornby Uribe, Amy Jean 02 December 2010 (has links)
The purpose of this classroom-based study was to create a variation of the Dictogloss that is successful in teaching target grammar within a meaningful context in beginning level secondary foreign language classrooms. Specifically, the study aimed to find out if there were differences in the amount of target grammar (demonstrative adjectives and the imperfect tense) noticed, learned and used by students in the three treatment groups: Treatment Group 1 completed a traditional Dictogloss with the last phase being a self-reflection activity, Group 2 was the same as Group 1, except the learners saw a written version of the text during the first reading in addition to hearing the text. Both the written text and a whole class discussion during the last stage of the Dictogloss were added to the lessons completed by Group 3. Differing from traditional DG studies that tend to examine Language Related Episodes, quantitative data was collected via pre, immediate post and delayed post-tests which consisted of multiple-choice and fill-in-the-blank questions. Although there were significant within-group differences for all three groups, indicating that the participants in all groups noticed and began learning the target grammar, there were no significant between-groups differences, suggesting that the addition of the written text and class discussion did not increase the amount of target grammar learned by the students. While the test scores showed that the participants’ knowledge of the TG did improve, the fact that many participants never scored above chance level shows that the Dictogloss is not an effective stand-alone activity for teaching TG. Qualitative data was also collected via student surveys and the written metatalk produced during self-reflection activities. The participants were asked what they liked, did not like and what they learned during the Dictogloss lesson. The data was analyzed using Content Analysis which revealed three themes: organization and administration of the Dictogloss based on the theoretical framework of the Dictogloss, issues regarding the texts and the Dictogloss and learning. The collaborating classroom teacher was interviewed two times in order to further analyze the effectiveness of using the variations of the Dictogloss with beginning Spanish FL learners. / text
119

"Att ha inflytande eller att vara underlägsen?" - En kvalitativ studie om hur psykologstudenter vid Örebro universitet upplever handledning under de kliniska momenten på psykologprogrammet / "Having influence or being inferior?" - A qualitative study examining how psychologist students experiences supervision at Örebro university during the clinical courses at the psychologist program

Arokiam, Emma, Ludvigsson, Magdalena January 2014 (has links)
No description available.
120

Apprentissage de problèmes de contraintes

Lopez, Matthieu 08 December 2011 (has links) (PDF)
La programmation par contraintes permet de modéliser des problèmes et offre des méthodes de résolution efficaces. Cependant, sa complexité augmentant ces dernières années, son utilisation, notamment pour modéliser des problèmes, est devenue limitée à des utilisateurs possédant une bonne expérience dans le domaine. Cette thèse s'inscrit dans un cadre visant à automatiser la modélisation. Les techniques existantes ont montré des résultats encourageants mais certaines exigences rendent leur utilisation encore problématique. Dans une première partie, nous proposons de dépasser une limite existante qui réside dans la nécessité pour l'utilisateur de fournir des solutions du problème qu'il veut modéliser. En remplacement, il nous fournit des solutions de problèmes proches, c'est-à-dire de problèmes dont la sémantique de fond est la même mais dont les variables et leur domaine peuvent changer. Pour exploiter de telles données, nous proposons d'acquérir, grâce à des techniques de programmation logique inductive, un modèle plus abstrait que le réseau de contraintes. Une fois appris, ce modèle est ensuite transformé pour correspondre au problème initial que souhaitait résoudre l'utilisateur. Nous montrons également que la phase d'apprentissage se heurte à des limites pathologiques et qui nous ont contraints à développer un nouvel algorithme pour synthétiser ces modèles abstraits. Dans une seconde partie, nous nous intéressons à la possibilité pour l'utilisateur de ne pas donner d'exemples du tout. En partant d'un CSP sans aucune contrainte, notre méthode consiste à résoudre le problème de l'utilisateur de manière classique. Grâce à un arbre de recherche, nous affectons progressivement des valeurs aux variables. Quand notre outil ne peut décider si l'affectation partielle courante est correcte ou non, nous demandons à l'utilisateur de guider la recherche sous forme de requêtes. Ces requêtes permettent de trouver des contraintes à ajouter aux modèles du CSP et ainsi améliorer la recherche.

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