The aim of this work is to suggest the solution for the new technology of rotor grooves machining for vanes of the steam turbine. It contains the technology of rotor grooves machining. Various criteria are taken into account and the final solution is adapted to the conditions of EKOL, spol. s r.o. company. Technical and economical evaluation.

The subject of this thesis is to assess the suitability of the new process of welding roots of welds by the rotors of steam turbines plasma jet. The new proposed method uses a combination of welding the weld root plasma with the method of submerged-arc welding, however the submerged-arc welding is not subjekt of this work. The tests performed were verified by the possibility of welding the weld root of the plasma jet – Keyhole method without filler material. The aim was to find the optimum welding parameters to achieve the required weld quality, particularly with regard to geometry of weld. Turbine rotors are made of heat resistant steels, which have high strength at high temperatures. In all described tests have been used steel 30CrMoNiV 5-11....Mat. No. 1.6946.

<p>Radi obezbeđivanja okruženja koje podstiče zdravlje i zdrave izbore, značajni istraživački napori usmeravaju se u pravcu pronalaženja efektivnih modela promocije fizičke aktivnosti i blagostanja dece tokom boravka u &scaron;koli.<br />Imajući u vidu nedostatak odgovarajućih istraživanja u na&scaron;oj sredini, sprovedeno je istraživanje sa ciljem da se ispitaju efekti dva inovativna modela &scaron;kolskog odmora na psihosomatski status učenika mlađeg &scaron;kolskog uzrasta i nasilje u &scaron;koli.<br />U prvoj interventnoj grupi (I1), ispitanicima su svakodnevno bili dostupni rekviziti za vežbanje, u drugoj interventnoj grupi (I2) je svakodnevno realizovan strukturirani program vežbanja, dok su se ispitanici kontrolne grupe (K) tokom velikog odmora bavili aktivnostima po svom izboru. Intervencije su trajale dva meseca.<br />Pripadnost grupi (I1, I2, K) predstavljala je nezavisnu istraživačku varijablu, dok su zavisne istraživačke varijable bile: fizička aktivnost učenika tokom odmora, morfolo&scaron;ke i motoričke karakteristike učenika, konativne karakteristike (samo-vrednovanje i optimizam), zdravstveni status (izostajanje iz &scaron;kole zbog bolesti) i nasilje u &scaron;koli (učestvovanje učenika u nasilju i izloženost nasilju). Za prikupljanje podataka kori&scaron;ćena je antropometrijska metoda, motoričko testiranje, upitnici (skale), sistematsko posmatranje i analiza &scaron;kolskih dokumenata. Dobijeni podaci obrađeni su odgovarajućim statističkim metodama.<br />Rezultati pokazuju da različiti modeli &scaron;kolskog odmora mogu imati različite efekte na različite aspekte psihosomatskog statusa učenika i nasilje u &scaron;koli. Potrebno je dalje ispitivati modele koji bi bili efektivni u transformaciji psihosomatskog statusa učenika i optimizaciji &scaron;kolske klime.</p> / <p>In order to provide an environment that enhances health and healthy choices, significant research efforts are put in identifying effective models of children&rsquo;s wellbeing and physical activity promotion while in school.<br />Bearing in mind an existing research gap, the study was conducted with an aim to examine effects that two innovative models of recess have on the psycho-somatic status of students and violence in school.<br />In first intervention group (I1), participants were provided with exercise equipment during recess, in the second intervention group (I2) structured exercise program was delivered every day, while participants from the control group (C) have spent recess on their own. The interventions took two months.<br />Group affiliation (I1, I2, C) was the independent variable, and the dependent variables were: students&rsquo; physical activity during recess, anthropometric and motor characteristics, conative characteristics (self-evaluations, optimism), health status (school absences because of medical reasons), school violence (students being perpetrators/victims). Data was gathered by anthropometry, motor testing, questionnaires (scales), observation and school document analysis. The data was analyzed by proper statistical procedures.<br />The results show that different recess models may have different effects on different aspects of students&rsquo; psycho-somatic status and school violence. Further examination of models effective in the transformation of the psycho-somatic status of students and optimization of school climate is needed.</p>

Schoolyards play an important role in the Icelandic education system. Students aged 6 to 12 years old are required to go outdoors for recess at least two times per day. To play, get fresh air and to regain energy for upcoming classes. The schoolyards are even sometimes used for outdoor education where the students can experience their nearest environment. The children spend a great time of their childhood in school, which should support their well-being by offering an environment of good quality.The thesis main objective is to examine the importance of outdoor lighting in Icelandic schoolyards by the dark winter days. Since Iceland is located at high latitudes, the amount of daylight varies between seasons, with shorter days by winter but longer and brighter days by the summer.The structure of the thesis is a combination of research background and a case study. The research background introduces the positive link between the outdoors and well-being and how the mindset towards the winter can change the perception of darkness. Possibilities of outdoor lighting are examined, how lighting can contribute to the users and the identity of urban spaces. The case study examines two Icelandic schools where the current conditions are analyzed. Qualitative interviews were carried out to gain insight from school employees about the school environment and their experience of the students‘ well-being during the dark winter months. Finally, a lighting proposal is introduced that illustrates how layers of light can enrich the school outdoor environment.It can be truly said that outdoor lighting is of high importance in Icelandic schoolyards, for the students to see and experience the schoolyard by dark winter days. It is important that the lighting is in context with the schoolyard elements and thereby enhancing the quality of the environment.

Les potentialités du nitrure de gallium (GaN) et notamment de l'hétérostructure AlGaN/GaN, semiconducteur à large bande interdite, en font un matériau particulièrement intéressant en électronique de puissance, notamment pour des applications haute tension, haute température et haute fréquence. L'objectif de ce travail de thèse était de développer et d'optimiser l'étape d'isolation de la grille lors la réalisation de transistors MIS-HEMT de puissance sur hétérostructure AlGaN/GaN, le but étant de réduire les courants de fuite de grille sans perturber les propriétés du transistor. Après avoir évaluation, le choix s'est porté sur l'alumine Al2O3 déposé par ALD comme diélectrique de grille. L'étude s'est d'abord concentrée sur l'analyse de l'influence de traitements, chimiques ou plasma, sur la contamination de la surface d'AlGaN au travers d'analyses XPS et AFM. Puis, l'influence du diélectrique de grille a été évalué à travers la réalisation et la mesure électrique de dispositifs, diodes et transistors, en variant les méthodes de dépôt par ALD. Enfin, l'impact d'un recess par gravure ICP-RIE partielle ou complètes de la barrière d'AlGaN sous la grille a été étudiée. La réalisation d'un HEMT passe par l'étape critique du dépôt du diélectrique de grille sur le semiconducteur, et le contrôle de la qualité de l'interface " diélectrique/AlGaN " est donc une étape fondamentale car elle influe sur les propriétés électriques du composant. Ce contrôle comprend le traitement de surface du semiconducteur, mais aussi la nature et la technique de dépôt du diélectrique. Ainsi il apparaît à travers l'étude qu'un traitement de surface à l'ammoniaque à haute température est le plus efficaces pour retirer les contamination en oxydes natifs. Les mesures électriques, C(V) et Id(Vg), ont quant à elle montrés la supériorité de la PEALD par rapport à un dépôt thermique conventionnel. Ceci peut s'expliquer par le fait que le plasma oxygène qui entre jeu lors du dépôt de l'alumine par PEALD semble nettoyer la surface lors des premiers cycles, retirant notamment la contamination carbone. Cela permet d'avoir une meilleure interface entre l'alumine et le semi-conducteur, limitant les pièges à l'interface et dans l'oxyde. Cela a réduit de manière considérable les courants de fuite de grille, sans détériorer la qualité et la rapidité de la transition entre l'état on et off. De plus, les HEMTs réalisé étant de type normally-off, le recess de grille par gravure ICP-RIE a été implémenté afin de rendre moins négative la tension de pincement. Cela a été réalisé avec succès, notamment avec la réalisation d'un composant de type noramlly-off grâce à un recess total de la barrière d'AlGaN sous la grille. Des résultats à l'état de l'art ont été obtenus à travers une approche simple, et un processus de création de transistors robuste et hautement reproductible, avec une réduction importante des courants de fuite de grille et une pente sous le seuil record. Afin de compléter l'étude il conviendra par la suite de réaliser des études de fiabilité, notamment à travers des mesures dynamiques pour évaluer notamment les phénomènes de dégradation du Ron. / With its large band gap, Gallium Nitride (GaN) semiconductor is one of the most promising materials for new power devices generation thanks to its outstanding material properties for high voltage, temperature and frequency applications. The main objective of this thesis was the development and optimization of the insulating step taking place in the elaboration of MIS-HEMT transistors on an AlGaN/GaN heterstroctructure. In order to reduce gate leakage currents without degrading the device properties, alumina Al2O3 deposited by ALD was chosen as a gate dielectric. The study was first centered on the influence of surface treatments, chemical or plasma, regarding surface contamination. Their impact was analyzed through XPS and AFM. Secondly, electrical measures were performed on complete MIS-HEMT diodes and transistors to evaluate the influence of the alumina insulating layer depending on the ALD deposition method. Lastly, partial and full recess of the AlGaN barrier was studied via ICP-RIE etching. The gate dielectric deposition is one of the crucial steps intervening in the HEMT creation process. The quality and control at the Al2O2/AlGaN interface being paramount, it will directly influence the device's electric properties. This involves control ing the semiconductor surface, but also the nature and deposition technique of the dielectric. As such, an ammonia-based treatment at high temperature appears to be the most efficient in reducing native oxygen contamination. Regarding electric performances, C(V) and Id(Vg) measures showed the superiority of PEALD compared to traditional thermal ALD deposition. This can be explained by the fact that the oxygen plasma used as oxydant during the alumina deposition by PEALD seems to clean the surface during the first cycles, mostly by reducing carbon contamination. This allowed to achieve a better interface between the semiconductor and the insulting layer, thus limiting traps at the interface or in the oxyde. This allows to considerably reduce gate leakage currents, without degrading the quality and transition sharpness between the on and off state. Moreover, the realized HEMTs being normally-off, gate recess etching via ICP-RIE was implemented in order to make the threshold voltage less negative. This was successfully achieved, especially through the realization of a normally-off transistors thanks to a full recess of the AlGaN barrier under the gate. State of the art results were achieved through a simple approach, and a robust and highly reproducible transistor elaboration process, with great reduction of gate leakage currents and a record sub-threshold slope. In order to complete the study, it will be necessary in the future to proceed to viability studies, especially through dynamic electric evaluation, in order to evaluate for instance Ron degradation phenomenons.

Made available in DSpace on 2014-12-17T15:30:55Z (GMT). No. of bitstreams: 1 Eudivar Correia de Farias Neto_DISSERT.pdf: 1661843 bytes, checksum: 00073311cd74dc1565ed066097489ecc (MD5) Previous issue date: 2010-07-27 / This study clinically evaluated the relationship of gingival recessions with the periodontal index of gingival and plaque, dental alignment, keratinized mocous, type of periodontal, and occlusal disorders. Study participants were individuals aged between 19 and 33 years. The evaluations were performed by using questionnaires and clinical examinations. In subjects examined, the teeth were assessed and divided into groups (Molars, premolars, canines and incisors). The gingival recession were measured in the central region of the teeth and individuals were subject to disclosure to the plate and observing the poll of plaque and gingival index, respectively. 558 teeth were examined, with 24.1%, 135 had gingival recession greater than or equal to 1mm. Through the combination of tests used to evaluate the average of the recession and its relationship with the variables studied, we observed that the degree of recession of the elements assessed dental showed, almost for the most part, when higher values associated with the index plaque (p = 0.101), Gingival Index (p = 0.053), dental alignment (p = 0.962), width of keratinized mocous (p = 0.004) and type of periodontium (p = 0.033), however statistically significant difference could only be considered when related the recessions in the keratinized mocous and the type of the periodontium. Although we identify, when we evaluate the whole set of teeth that occlusal disturbances (p = 0.002) were more strongly associated with cases of gum recession that the gingival index (p = 0.006), however, these two conditions were correlated with the cases of recession, contributing to its occurrence / Este trabalho avaliou clinicamente a rela??o das recess?es gengivais com o ?ndice de placa, ?ndice gengival, alinhamento dental, mucosa ceratinizada, tipo de periodonto, e dist?rbios oclusais. Participaram do estudo indiv?duos com idades variando entre 19 e 33 anos. As avalia??es foram realizadas utilizando-se question?rios e exames cl?nicos. Nos indiv?duos examinados, os dentes foram avaliados e divididos por grupos (Molares, pr?molares, caninos e incisivos). As recess?es gengivais foram mensuradas na regi?o central dos dentes e os indiv?duos foram submetidos ? evidencia??o de placa e sondagem para observa??o dos ?ndices de placa e gengival, respectivamente. Foram examinados 558 dentes, sendo que 24,1%, isto ?, 135 apresentavam recess?o gengival maior ou igual a 1mm. Por meio dos testes de associa??o utilizados para avalia??o da m?dia das recess?es e sua rela??o com as vari?veis pesquisadas, observou-se que o grau de recess?o dos elementos dent?rios avaliados apresentaram, quase que em sua maioria, valores m?dios maiores quando associados ao ?ndice de Placa (p=0,101), ?ndice de Gengival (p=0,053), alinhamento dent?rio (p=0,962), largura da mucosa ceratinizada (p=0,004) e tipo de periodonto (p=0,033), no entanto diferen?a estatisticamente significante s? p?de ser considerada quando relacionamos as recess?es com a mucosa ceratinizada e com o tipo do periodonto. Ainda foi poss?vel identificar, quando avaliamos todo o conjunto dos dentes que os dist?rbios oclusais (p=0,002) estiveram mais fortemente associados aos casos de recess?o gengival que o ?ndice gengival (p=0,006), no entanto, essas duas condi??es se mostraram correlacionadas com os casos de recess?o, contribuindo na sua ocorr?ncia

The recess is a place where many students meet and social context becomes a big part of their day. The recess offers opportunities for students to practice social interaction, which is also a large part of the leisure-time centre's mission. The study is based on the socio-cultural perspective and the investigation is based on qualitative methods such as interviews and observations. The purpose of the study is to find out more about how student’s interaction is emphasized during the recess through free play, controlled and student-led activities. Through the interviews, we want to investigate how educators view their role and the opportunity to influence students' social learning. Finally, we want to draw attention to similarities in the social learning that takes place through play and participation in activities at the recess and the learning that takes place at the leisure-time centre.  The results of the study show that the different recess activities contribute in different ways to the students' social learning. The educators see both the pros and the cons of the different forms of recess activities and the conclusion is that a variety of break activities are needed to create social contexts for all students. The social interaction that takes place during the recess is largely reminiscent of what happens in the leisure-time centre's activities. / Rasten är en plats där många elever möts i sociala sammanhang, detta är en stor del av verksamheten. Rasten erbjuder möjligheter för eleverna att öva det sociala samspelet, vilket även är en stor del av fritidshemmets uppdrag. Studien utgår ifrån det sociokulturella perspektivet och undersökningen är baserad på kvalitativa metoder som intervjuer och observationer. Syftet med studien är att ta reda på hur elevernas samspel framhävs ute på rasten genom fri lek, styrda och elevledda aktiviteter. Genom intervjuerna vill vi undersöka hur pedagoger ser på sin roll och möjligheten till att påverka elevernas sociala lärande. Avslutningsvis vill vi uppmärksamma likheter i det sociala lärande som sker genom lek och deltagande i aktiviteter på rasten och det lärande som sker på fritidshemmet.   Resultatet av studien visar att de olika rastverksamheterna på olika sätt bidrar till elevernas sociala lärande. Pedagogerna ser både för och nackdelar med de olika rastverksamhetsformerna och slutsatsen är att en variation av rastverksamheter behövs för att skapa sociala sammanhang för alla elever. Det sociala samspel som sker på rasten påminner till stor del om det som sker i fritidshemmets verksamhet.

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Syftet med det utvecklingsinriktade arbetet var att skapa en hållbar rastverksamhet genom ett lånesystem där fokus var att utveckla elevernas förmåga att ta personligt ansvar. Studien undersöker hur elever kan bli delaktiga, utveckla personligt ansvar, känna trygghet samt vara fysiskt aktiva under rasten. Arbetet utgår från aktionsforskning där arbetet strukturerades upp i fyra delar, planera, agera, observera och reflektera. Det innefattade också intervjuer, gruppintervjuer och enkäter. Aktionerna genomfördes 1–2 dagar i veckan under tre veckor, sammanlagt blev det sju aktioner. Lånesystemet skapades i en av skolans bodar som eleverna hade tillgång till under sin skolrast. Lånesystemet innebar att låna redskap men också att hjälpa till med utlåning av redskap genom att vara hjälpreda. Resultatet av aktioner visade att det fanns ett stort intresse bland eleverna att vara delaktiga i lånesystemet, och att de kan ta ett personligt ansvar av de redskap de lånade. Det framkom även att ett lånesystem inte behöver bidra till den fysiska aktiviteten hos eleverna, och att elevernas trygghet på rasten påverkas av hur delaktiga lärare är och vilka normer som finns på skolan. I en slutreflektion diskuterades det att ett lånesystem inte behöver innebära att eleverna känner trygghet eller blir mer fysiskt aktiva.

Title: Additional physical activities of pupils of the 2nd grade of elementary school Objectives: The aim of this thesis is to describe and classify various possibilities of integrating physical activity into the school regime of pupils aged 11-15, which reduce the sedentary stereotype and help to fulfil the recommended amount of daily physical activity of pupils. Methods: In the theoretical part, a search of literature and electronic sources was carried out. The practical part included a questionnaire to determine the current situation in schools in the Czech Republic. The questionnaire was created in Google Forms, Mailchimp was used to distribute the questionnaire and statistical processing of the results was completed in Microsoft Excel. The selection of respondents was randomly stratified by districts. Results: The theoretical part described a number of teaching forms and methods related to movement, including specific suggestions and inspirations in various subjects. The results of the questionnaire showed a high level of interest in the topic among school officials, but also a rejecting attitude of some respondents. Schools relatively often offer the possibility to spend breaks outdoors and also include walks into their lessons, or combine teaching with movement. However, corridor and...