Metapovrchy sú nanoštruktúrované povrchy vytvorené za účelom špecifického ovládania propagácie svetla. Predstavujú revolúciu v oblastiach ultratenkých optických prvkov a nanofotonických obvodov. Zakomponovaním laditeľných dielektrických materiálov do metapovrchov sa otvára možnosť aktívne ovládať ich optické vlastnosti aj po tom, čo boli vyrobené. Oxid vanadičitý (VO2) takéto ladenie umožňuje vďaka svojej fázovej premene už pri teplote okolo 67°C a preto sa radí k najsľubnejším z laditeľných dielektrických materiálov. Nakoľko je možné postupnú fázovú premenu vo VO2 vybudiť opticky a lúč svetla je možné fokusovať do stopy s veľkosťou pár stoviek nanometrov, laditeľné metapovrchy obsahujúce VO2 by mohli byť ladené postupne a dokonca s nanometrovým rozlíšením. V tejto práci skúmame fázu a amplitúdu svetla po prechode VO2 nanoštruktúrami usporiadanými do metapovrchu navrhnutého pre viditeľnú zložku elektromagnetického žiarenia. Výskum fáze a amplitúdy je založený na numerických simuláciách VO2 nanoštruktúr (stavebných kameňov metapovrchov), ktoré sú následne overené experimentálnymi výsledkami. VO2 nanoštruktúry vykazujú taktiež Mieho dielektrické rezonancie, ktoré sú v závere tejto práce využité v postupne laditeľnom metapovrchu fungujúcom vo viditeľnej oblasti. Okrem termálneho ladenia je možné vyrobený metapovrch ovládať taktiež opticky, čo dokazuje možnosť postupného ladenia na nanometrových rozmeroch.

The purpose of this thesis is to present methods for visibility determination and to design and implement an application to demonstrate visibility determination in a 3D maze.

This work is focused on free space optical communication in visible electromagnetic spectrum known as visible light communication (VLC). Basic parameters of standard IEEE 802.15.7, advantages and disadvantages are discussed in the theoretical part of this work. Furthermore, optical link and it´s parts are described. The largest part of the work is focused on design and simulation of optical receiver for visible spectrum. Selection of component, noise and SNR calculation is discussed as well. This work also includes calculation of power energy in different parts of optical connection, PCB design of optical receiver, transmitters and power supply and output board. Behavior and parameters of electronic circuits, components and optical connection are explored, measured and compared with theoretical values.

Syftet med denna studie var att undersöka hur förskollärare synliggör sitt arbete med matematik i förskolans verksamhet. Frågeställningarna i denna studie besvarar förskollärarna hur de synliggöra matematiken för barnen i förskolan. Studien bygger på tidigare forskning och kvalitativ metod i form med insamlat data från aktiva förskollärare. Utgångspunkten är Vygotskijs teori och det insamlade materialet har analyserats utifrån teorin det sociokulturella perspektivet. Detta perspektivet är vald för att få en förståelse för hur förskollärarna arbetar med matematiken. Resultatet i studien visar att de kompetenta förskollärarna använder matematiken i planerande och oplanerade aktiviteter för barnen. Resultatet påvisar även att det är förskollärarnas ansvar att väcka en nyfikenhet hos barnen för att göra matematiken spännande och lustfylld.

Effective principal's instructional leadership yields high achieving schools (Dhlamini, 2008:105; Hallinger and Heck, 1998; Hargreaves, 1994; Hopkins, 2001; Effective principal’s instructional leadership yields high achieving schools Khuzwayo, 2005; Kruger, 1999; Mbatha, 2004; Mthombeni, 2004). Annual National Assessment (ANA) (DoE, 2009) and Systemic Evaluation (SE) in 2001 and 2007 (DoE, 2008) revealed that South African learners are not able to read and write, and that their numeracy skills are not well developed. The performance is also evident in the Grade 12 performance which has not shown great improvement over the years. In an effort to address the poor performance as experienced in schools, the department of education introduced Resolution 1 of 2008 (DoE, 2008) which requires principals to provide professional leadership which is based on curriculum management; and to take accountability for the quality of learning that takes place within the school. The poor learner achievement in schools triggered the question about the quality of education provided in the primary schools and the instructional leadership provided by primary school principals as it is a foundation to the schooling system. A qualitative approach was used to explore the practices of primary school principals as instructional leaders and the implications for learner achievement. Six primary schools in the Tshwane West district in Gauteng province were sampled for the research. The research revealed the following distinguishing factors by those schools that performed extremely well in the Annual National Assessment (ANA) (DoE, 2009) and Systemic Evaluation (SE) in 2001 and 2007 (DoE, 2008): <ul> <li> The principal has to establish good relations amongst and between educators and learners and also foster two-way communication.</li> <li> The principal should make sure that academic results are analysed and interventions strategies are followed to improve learner achievement.</li> <li> Educators should be encouraged by the principal to perform a self-reflection of their teaching performance. The principal has to provide support for underperforming educators and encourage them to develop themselves professionally.</li> <li> The principal needs to conduct class visits.</li> <li> The principal should ensure that teaching and learning time is protected and that educators and learners attend classes punctually.</li> <li> The principal needs to keep abreast of the curriculum and instruction changes and provide the necessary support and guidance.</li> <li> The principal has to ensure that instruction is given priority and is central to the school’s activities.</li></ul> The above-mentioned factors proved to be essential in the instructional leadership of the primary school principal in ensuring improved learner achievement in schools. Copyright / Dissertation (MEd)--University of Pretoria, 2011. / Education Management and Policy Studies / unrestricted

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Leaf area index (LAI) is a versatile indicator of crop growth that is used to estimate evapotranspiration (ET), monitor nitrogen status, and estimate crop yield. Traditional methods for measuring LAI can be improved using high resolution remote sensing. The aim of this study was to compare approaches for estimating LAI from UAV-derived visible vegetation indices. Coincident ground-based and remotely sensed data were obtained from two irrigated wheat fields and were sampled at a total of 5 events in 2019 and 2020. Ground-based LAI was measured with a ceptometer and remotely sensed images were collected using a consumer-grade UAV. Mosaiced orthophotos were resampled from native (0.06m) spatial resolution to increasingly coarser spatial resolutions up to 3 m by either a direct or ladder resampling method. Visible band color information (RGB) was extracted from the orthophotos at the points that LAI was collected within field and 12 different visible vegetation indices (VVIs) were calculated. Linear regression was performed to evaluate the relationships between wheat LAI and each calculated VVI for all spatial resolutions and resampling methods. Three VVIs, visible atmospherically resistant index (VARI), normalized green-red difference index (NGRDI), and modified green-red vegetation index (MGRVI), estimated LAI equally well (R2= 0.66, 0.66,0.66; RMSE=0.74,0.73,0.73; MAE=0.57,0.56,0.56) when resampled to 3 m spatial resolution with the ladder resampling method. These results demonstrate the potential to remotely estimate LAI using only RGB cameras and consumer grade drones. An additional aim of this study was to evaluate use of a remotely sensed visible vegetation index to characterize the spatial variability of LAI within irrigated wheat fields. Variation of LAI was measured with a ceptometer on random nested grids at two sites with pre-determined management zones in 2019 and 2020. Coincident digital imagery was collected using a consumer-grade unmanned aerial vehicle (UAV). A visible atmospherically resistant index (VARI) LAI estimation model was applied to red, green, blue (RGB) UAV imagery using a ladder resampling approach from 0.06 m to 3 m spatial resolution. There was significant within-field spatial and temporal variation of mean LAI. For example, in May at the Grace, ID location measured LAI ranged from 0.21 to 2.58 and in June from 1.68 to 4.15. The relationship of measured and estimated LAI among management zones was strong (R2=0.84), validating the remote sensing approach to characterize LAI differences among management zones. There were statistically significant differences in estimated LAI among zones for all sampling dates (P=0.05). We assumed a minimum difference of 15% between zone LAI and the field mean for justifying variable rate irrigation among zones, a threshold that corresponds with approximately a 10% difference in evapotranspiration rate. Three of the five sampling dates had LAI differences that exceeded the threshold for at least one zone, with all three having mean LAI of less than 2.5. The VARI model for estimating LAI remotely is more effective at identifying LAI differences among management zones at lower LAI. Application of this approach has potential for applications such as estimating evapotranspiration of irrigated fields and delineation of zones for variable rate irrigation.

Abstract The purpose of this master thesis is to investigate of what use the method Visual Planning can be in the construction industry in general and in the design phase of construction projects in particular.   The investigation and empirical part of the thesis has been based on semi-structured interviews with process developers, design managers and designers from Swedish companies where Visual Planning is used. The interviews have been the base for a comparative case study with the aim of providing an overview of how the method is currently used, interpreted, experienced and perceived in the Swedish construction industry and by its professionals. The master thesis has been made in collaboration with the Swedish consultancy firm Tyréns AB in Stockholm.   The results of the interviews differ on an individual level. The majority of the respondents are however positive and believe in the future of the methods. All respondents stress the lacking documentation, however, as the major difficulty. Several respondents have stressed the difficulties of working in a scattered team due to the analogue format as a shortcoming of the method as well. The biggest benefits stated are the easy accessible overview provided and the clarification of commitments, due to the active participation of the design participants, the analogue format, and the way of mapping of the information process.   It has been found that Visual Planning can be of use as a support in the process of construction project management, since it may facilitate the understanding of how to reach objectives and provide an easy accessible overview of the progress and status of a project. It should however be viewed as a complement to the process of construction project management, and not as a replacement. In conclusion it may facilitate earlier problem solving, since commitment is raised, which in the end facilitates the project to stay within budget as well as to meet the deadline. / Sammanfattning Syftet med detta examensarbete är att utreda vilken nytta metoden Visuell Planering kan vara av i byggbranschen i allmänhet och projekteringsfasen av byggprojekt i synnerhet.   Undersökningen har baserats på semi-strukturerade intervjuer med processutvecklare, projekteringsledare och projektörer från företag inom den svenska byggsektorn där Visuell Planering används. Intervjuerna har utgjort grunden för en jämförande fallstudie med avseendet att skapa en överblick och insyn i hur metoden i dagsläget används, tolkas och upplevs i den svenska byggbranschen och av yrkesverksamma i branschen. Examensarbetet har genomförts i samarbete med konsultföretaget Tyréns AB i Stockholm.   Intervjuresultaten varierar på individnivå. Majoriteten av intervjupersonerna är dock positiva och tror på metodens framtid. Alla tillfrågade beskriver den låga mängden dokumentation som det största problemet hos metoden. Flera yrkesverksamma beskriver även metodens tillkortakommanden då arbete bedrivs i spridda team. En följd av metodens analoga format.  Den genererade lättöverskådliga helhetsbilden och förtydliganden av åtagande och engagemang, som följd av projektmedlemmarnas aktiva deltagande, det analoga formatet och sättet som informationsprocessen kartläggs beskrivs som det största vinsterna.   Det har framkommit att Visuell Planering kan vara av användning och fungera som ett stöd i byggprojektledning, då metoden underlättar förståelse för hur mål ska uppnås och skapar en lättuppfattad bild av ett projekts status och framåtskridande. Metoden bör dock ses som ett komplement i processen av byggprojektledning och projekteringsledning, snarare än en ersättning. Visuell Planering kan slutligen främja problemlösningen i tidigare skeden, då känslan av förpliktelse, åtagande och engagemang höjs, vilket i sin tur skapar bättre möjligheter för projektet att hålla sig inom budget så väl som att möta deadline.

A rubric specifically for speaking skills was recently implemented and practiced in an English classroom for grade 6, in a school in the south of Sweden. The predetermined effected results of how the rubric works is debated among many schools and researchers, but no research have been done on the actually effects specifically in this area recently. Therefore, the overall aim for this study is to analyse how this specific tool for the spoken language learning works in practice. The study includes theory and previous research, which will be presented and moreover discussed in relation to the findings. Semi-structured interviews will be used and the participants are two teachers who teached year 6 at the same school in a city in the south of Sweden; both used the rubric in the English classroom. I investigated why and how it was implemented and used in the English classroom. Moreover, I answered the questions of what kind of rubric was used; and by comparing the rubric to the knowledge requirement in the syllabus, I determined how it outlined the knowledge requirements. In addition, by analysing the teachers’ answers, I investigated how the rubric affected the students’ learning and how it facilitated the learners’ self-awareness of their language development. The conclusion demonstrates that the rubric for speaking skills is beneficial for the majority of the students, but it has a negative effect on the students who are on a lower knowledge level than the rubric includes.

En réponse aux problèmes croissants liés aux transports routiers - accidents, pollutions,congestions - les véhicules à faibles émissions, équipés de systèmes de transports intelligents (ITS)sont progressivement développés. Si la finalité de cette démarche est le véhicule entièrementautonome, on peut néanmoins s'attendre à voir d'abord sur nos routes des véhicules automatisés surdes phases de conduite spécifiques. C'est le cas du convoi automatisé, qui permet à plusieursvéhicules de rouler en convois de manière automatique et donc d'augmenter la capacité des voies decirculation tout en réduisant la consommation de carburant. La fiabilité de cet ITS repose surplusieurs briques technologiques, et en particulier sur la mesure de distance et la transmission dedonnées véhicule-véhicule (V2V).De nombreux systèmes permettent de réaliser ces deux fonctions vitales comme, par exemple, lesradars ou lidars pour la mesure de distance et la technologie IEEE 802.11p pour la communicationvéhiculaire. Si ces différents dispositifs présentent de très bonnes performances, ils sont néanmoinsparticulièrement sensibles aux interférences, qui ne cessent de se multiplier à mesure que le nombrede véhicules équipés augmente et que le trafic est dense. Pour pallier les dégradations deperformances induites par de telles situations, des technologies complémentaires pourraient donc êtreutiles. Le récent développement des diodes électroluminescentes (LED) blanches, en particulier pourl'éclairage automobile, a permis l'émergence des communications optiques visibles sans fil (VLC).Les phares à LED sont alors utilisés pour transmettre des données entre véhicules et avec lesinfrastructures. Malgré la puissance limitée de ces éclairages, plusieurs études ont montré qu'unetransmission de qualité est possible sur quelques dizaines de mètres, faisant de la VLC uncomplément particulièrement intéressant à l'IEEE 802.11p, en particulier pour les convoisautomatisés. Par analogie, on peut alors se demander si les phares ne pourraient pas être aussi utiliséspour mesurer la distance V2V.Le but de cette thèse est donc de proposer et évaluer un système dédié aux situations de convoisautomatisés qui, à partir des phares avant et arrière des véhicules, transmet des données et mesuresimultanément la distance V2V. Dans un premier temps, une étude détaillée de l'état de l'art de laVLC pour la communication V2V est effectuée afin de déterminer l'architecture de base de notresystème. La fonction de mesure de distance est ensuite ajoutée, après une revue des différentestechniques usuelles. Une fois l'architecture générale du système établie, elle est dans un premiertemps validée par des simulations avec le logiciel Simulink. En particulier, les différents paramètressont étudiés afin de déterminer leur impact sur la résolution de mesure de distance et les performancesen transmission de données, puis afin de les optimiser. Si ces simulations fournissent des indicateursimportants pour la compréhension du système, elles ne peuvent cependant remplacer les tests d'unprototype réel. L'implémentation de ce prototype est alors détaillée ainsi que les tests réalisés dansdifférentes configurations. Ces différents tests démontrent l'intérêt des solutions proposées pour lamesure de distance et la communication V2V en convois automatisés. / In response to the growing issues induced by road traffic - accidents, pollution, congestion- low-carbon vehicles equipped with intelligent transportation systems (ITS) are being developed.Although the final goal is full autonomy, the vehicles of the near future will most probably be selfdrivingin certain phases only, as in platooning. Platooning allows several vehicles to moveautomatically in platoons and thus to increase road capacity while reducing fuel consumption. Thereliability of this ITS is based on several core technologies and in particular on vehicle-to-vehicle(V2V) distance measurement and data transmission.These two vital functions can be implemented with several kinds of systems as, for instance, radars orlidars for range-finding and IEEE 802.11p-based devices for vehicular communication. Althoughthese systems provide good performances, they are very sensitive to interferences, which may be agrowing issue as the number of vehicles equipped will increase, especially in dense traffic scenario.In order to mitigate the performance degradation occurring in such situations, complementarysolutions may be useful. The recent developments of white light-emitting diodes (LED), especiallyfor the automotive lighting, has allowed the emergence of visible light communication (VLC). WithVLC, the vehicle headlamps and taillights are used to transmit data to other vehicles orinfrastructures. Despite the limited optical power available, several studies have shown thatcommunication over tens of meters are possible with a low bit error rate (BER). VLC could thus bean interesting complement to IEEE 802.11p, especially in platooning applications. By analogy, onecould wonder if the automotive lighting can also be used for V2V range-finding.The goal of this thesis is thus to propose and evaluate a system dedicated to platooning configurationsthat can perform simultaneously the V2V distance measurement and data transmission functionsusing the headlamps and taillights of the vehicles. The first step of this study is thus a detailed stateof-the art on VLC for V2V communication that will lead to a first basic architecture of our system.Then, the range-finding function is added, after a careful review of the classical techniques. Once thegeneral architecture of the system is drawn, it is validated through simulations in the Simulinkenvironment. The different degrees of freedom in the system design are especially studied, in orderfirst to evaluate their impact on the measurement resolution and the communication performances,and then to be optimized. Although these simulations provide crucial keys to understand the system,they cannot replace real prototype testing. The implementation of the prototype is thus fullydescribed, along with the results of the different experiments carried out. It is finally demonstratedthat the proposed solution has a clear interest for V2V range-finding and communication inplatooning applications.