A preliminary investigation of the added properties called added mass, added damping and added stiffness have been performed for a Kaplan turbine. The magnitude of dimensionless numbers have been used in order to classify the interaction of the fluid and the solid. The classification is done to bring clarity in which of the added properties are of importance for the system. The diameter of the runner and the hub have been calculated using the power output and the head for a Kaplan turbine. These dimensions have been used to determine the magnitude of the dimensionless numbers along with the velocity of the fluid. It turned out that all added properties affect the turbine, however, the magnitude of them are quite different. The magnitude of the added mass and the added damping are greater than the added stiffness, which often is neglected. The added mass can be determined if the natural frequencies of the structure in air and in water are known. The difference in natural frequencies can be used to determine the added mass factor and thereby the added mass of the system. The added damping can be determined by the change in damping ratio for different surrounding fluids. This was done using the simulation software ANSYS Workbench v.17.1, where two different types of simulation were used, ”acoustic coupled simulation” and ”two way coupled simulation”. The complexity of the geometry of the Kaplan turbine was simplified to a disc and a shaft. The result for the added mass was validated using results from an experiment [1]. The added damping could be determined, but not validated. The different types of simulation have been compared and it turned out that the added mass could be determined using ”acoustic coupled simulation” and ”two way coupled simulation”, but the added damping could only be determined using the ”two way coupled simulation”. / En preliminär undersökning av de adderade egenskaperna kallade, adderad massa, adderad dämpning och adderad styvhet har utförts för en Kaplan turbin. Magnituden av dimensionslösa tal har använts för att klassificera interaktionen av fluiden och soliden. Klassificeringen görs för att bringa klarhet i vilka av de adderade egenskaperna är av betydelse för systemet. Diametrarna för löphjulet och navet har beräknats utifrån effekt och fallhöjd för en Kaplan turbin. Dessa längder har använts för att bestämma magnituden av de dimensionslösa talen tillsammans med fluidens hastighet. Det visade sig att alla adderade egenskaper påverkar turbinen, men omfattningen av dem är helt annorlunda. Magnituden av den adderade massan och den adderade dämpningen är större än den adderade styvheten, som ofta försummas. Den adderade massan kan bestämmas om de naturliga frekvenserna av strukturen i luft och vatten är kända. Skillnaden i egenfrekvenser kan användas för att bestämma faktorn av den adderade massan och därigenom den adderade massan. Den adderade dämpningen kan bestämmas genom ändringen i dämpningsförhållande för olika omgivande fluider. Detta gjordes med hjälp av simuleringsprogrammet ANSYS Workbench v.17.1, där två olika typer av simulering användes, ”acoustic coupled simulation” och ”two way coupled simulation”. Komplexiteten i geometrin för en Kaplan turbin förenklades till en skiva och en axel. Resultatet för den adderade massan validerades med resultat från ett experiment [1]. Den adderade dämpningen kunde bestämmas, men inte valideras. De olika typerna av simulering har jämförts och det visade sig att den adderade massan kan bestämmas med hjälp av både ”acoustic coupled simulation” och ”two way coupled simulation”, men den adderade dämpningen kunde endast bestämmas med hjälp av ”two way coupled simulation”.

Due to the development of, and the opportunities that social media provides for different groups in society, companies and organizations are encouraged to be present on, and be a part of the new social media landscape. This research examines how five companies and five organizations use social media as a tool to create relationships with individuals, and what role social media plays in the daily communication work. The social media platforms discussed in this research companies and organizations can utilize not only to create an identity and work with branding, but also to apply two-way communication with individuals. The research applies qualitative interviews with representatives from each company and organization. The main findings revealed surprisingly that there are not any significant differences between companies’ and organizations’ way of using social media, but that it differs more between different kinds of companies and organizations. Most companies and organizations use different social media platforms for different purposes or to reach different target groups. Facebook and Instagram are the two platforms that most companies and organizations from the research use. Facebook is generally used to share information and Instagram to inspire. Furthermore, social media provides different possibilities to reach out to people than more traditional ways of communication such as print advertising and newsletters. Hence, social media plays an important role in the work with communication in order to reach out to people and can have a decisive effect for companies and organizations. The advantages of social media that the participating companies and organizations emphasized are that they get to have their own voice, they can themselves create interest and commitment, rather than using a PR-firm for example, and it enables two-way communication which in turn foster relationships with individuals. Finally, one of the biggest advantages highlighted is the fast communication that is enabled on social media platforms which keep the companies and organizations closer to the public

Master of Science / Department of Communications and Agricultural Education / Lauri M. Baker / The purpose of this study was to identify the needs of Kansas' agricultural producers in relation to financial and legal matters at a local level. The following research questions guided this study: 1) what services, identified by local producers, are needed in communities across Kansas to assist producers in times of financial and legal distress; 2) what are the perceptions among producers of the Kansas Agricultural Mediation Services (KAMS); 3) what brand attributes, names, and taglines would appeal to producers for an organization addressing their financial and legal distress; 4) how can organizations effectively market financial and legal services to producers? A qualitative study design was used in order to assess the research questions. Six focus groups were performed throughout the state in three different geographic locations. Participants were selected using purposive sampling in order to have one group of people familiar with the organization (KAMS) currently helping producers with their legal and financial issues and one unfamiliar group in each location. Grunig’s excellence in public relations model served as the conceptual framework for this study. Results of this study concluded that rural Kansas’ communities see a need for service organizations similar to KAMS. Participants value assistance with family farm transition planning as well as financial assistance. Participants saw marketing and promotion of the current services offered just as critical as having the services themselves. Participants felt these services should be marketed through two-way communication channels, such as social media, an organizational representative for face-to-face interaction, and collaboration with extension. Additionally, participants voiced strong opinions about various brand attributes.

Trådlös kommunikation mellan noder sker genom att skicka data över det trådlösa mediet, för att få kommunikationen att samspela har flertalet standarder utvecklats. En av dessa standarder är 802.15.4 med UWB PHY vars utformning är av en sådan karaktär att signalöverföringen blir störningstålig och osynlig för andra standarder. UWB används ofta till lokalisering och positionering, men kan även användas till en samtida dataöverföring då standardens utformning tillåter detta. Det var dock oklart med vilken prestanda detta kunde genomföras. Därför har den datakommunikationsprestandan undersöks. Den hypotes som följdes under arbetet var att ''genom att skicka data mellan positioneringsimpulserna möjliggörs användandet av samma enhet för positionering och datakommunikation, systemets prestanda påverkas då av MAC-metoden''. Ur hypotesen kom det tre frågeställningar: Vilken MAC-metod är lämplig för både positionering och dataöverföring? Är det möjligt att använda systemet för både positionering och dataöverföring genom att skicka data mellan positioneringsimpulserna? Vilken kommunikationsprestanda kan uppnås när systemet används för både postionering och dataöverföring? I arbetet bevisas hypotesen samt frågeställningarna med syftet att detta kunde komma att hjälpa till inom exempelvis robotiken, men även som ett alternativ till WiFi då UWB är både störningståligt och osynligt för andra standarder. Den iterativa metoden användes för att utveckla ett system som kunde lösa den kombinerade positioneringen och datakommunikationen. I prestandatesterna gick det att utläsa att hypotesen stämde förutsatt att parametrarna är korrekt. / Wireless communication between nodes is achieved by sending data over the wireless medium. In order to have communications interact different standards have been developed. One such standard is 802.15.4 with UWB PHY, designed such that the signal transmission becomes interference-resistant and invisible to other standards. UWB is often used for location and positioning, but the standard design also allows for a contemporary data transfer. However, it was unclear with what performance this could be implemented. Therefore, the data communication performance has been investigated. The hypothesis that was followed during the work posits that ''by sending data between the positioning pulses, the use of the same unit for positioning and data communication is made possible, and that the system's performance is then affected by the MAC method.'' Three questions arose from this hypothesis. Which MAC method is suitable for both positioning and data transfer? Is it possible to use the system for both positioning and data transmission by sending data between the positioning pulses? What communication performance can be achieved when the system is used for both positioning and data transfer? In this work the hypothesis and the research questions are verified with the intended purpose that it could be of help in the field of robotics and also as an alternative to WiFi, due to UWBs robustness and invisibility characteristics. An iterative process has been utilized throughout this work to build a system which could solve the combined positioning and data communication. In the following performance tests the hypothesis is verified, provided that the parameters used are correct.

Le projet Filière Bilingue (FiBi), qui a débuté à Bienne (Suisse) en août 2010, est un programme réciproque-immersif destiné aux élèves à partir de lʼécole enfantine. Cet enseignement leur permet de se plonger dans un monde bilingue (suisse-allemand et français), puis plurilingue (allemand, suisse-allemand et français). Ayant donc à se mouvoir dans des situations exolingues, les enfants doivent sʼappuyer sur des stratégies communicatives pour pouvoir interagir avec leurs interlocuteurs tout au long de la journée. Dans le cadre dʼun enseignement réciproque-immersif, ces stratégies communicatives vont constituer un élément fixe lors des interactions entre enfants et enseignants d’une part, et entre les enfants eux-mêmes d’autre part. Notre travail de recherche a pour objectif de mettre en évidence le développement de ces outils communicatifs de huit sujets de sexe féminin pendant les quatre ans entre l'école enfantine et la 2ème année d'école primaire. Les interviews guidées, qui constituent notre corpus, ont toutes été filmées, puis transcrites avec EXMARaLDA. Les stratégies communicatives observées dans les interviews guidées ont ensuite été codées au moyen du logiciel MAXQDA. Elles peuvent être classifiées en dix catégories principales : les stratégies d'évitement, d'alternance linguistique, d'imitation, d'exploration, de coopération, d'appel, de compensation, de transfert, ainsi que non verbales et paraverbales et paraphrastiques. Nous avons pu mettre en évidence des changements dans l’utilisation des stratégies communicatives au fil du processus d'apprentissage de la langue cible dans la complexité, la variété, la combinaison (utilisation simultanée) de plusieurs stratégies communicatives, l'utilisation consciente, ainsi que dans la fonction. / The project Filière bilingue (FiBi), which has been running since 2010, is a two-way immersion program by way of Swiss German, German and French starting at kindergarten in the city of Biel/Bienne, Switzerland. In these bilingual classes are both German and French speaking pupils confronted with both languages from the beginning of their schooling. Therefore, communication strategies are developed, not only between pupils, but also between the pupils and the teacher. The following research study focuses on various communication strategies utilised by eight female pupils over a period of four years, namely from kindergarten to the end of Year 2 of primary school. Through the FiBi project, five semi-structured interviews were taken and then transcribed with the software EXMARaLDA. Subsequently, these transcriptions were coded according to the communication strategy used via the software MAXQDA. From the analysed data, ten types of observed communication strategies were categorised: avoidance/omission, code switching, imitation, guessing, appeal for assistance, retrieval, nonverbal and para-verbal communication, paraphrasing, approximation, and transferring. The research has shown that as the pupils’ competence in the target language increases, so does the complexity, frequency, function, intertwining, and the consciousness use of the communication strategies.

Thesis advisor: Larry Ludlow / In this dissertation study, I examined the extent to which a relational network of teachers, administrators, two-way immersion (TWI) experts and mentors promote productive communities of practice (CoP). In a conventional instruction, teachers are often isolated in their classrooms, and a private practice culture prevails. In 2012, the Two-Way Immersion Network for Catholic Schools (TWIN-CS) was launched in an effort to support school reform by engaging school leaders and teachers to collectively learn toward implementing TWI models in their schools. Using the framework of communities of practice (Lave & Wenger, 1991; Wenger, 1999), I employed a case study design (Yin, 2009) to explore a national network of Catholic elementary school educators. Data sources included qualitative data featuring semi-structured interviews and quantitative source from a relational network survey. Qualitative results revealed that organizational features of TWIN-CS are critical in promoting participants’ learning to implement TWI. In particular, participants discussed the annual TWIN Summer Academy and bi-monthly webinars to be instrumental for their learning. Many participants also shared that an expansion of CoPs beyond TWIN-CS further prompted productive learning. However, the qualitative evidence also showed a lack of clear internal and external network structures and role definition, and sustaining connection beyond the Summer Academy and webinars were perceived as a great challenge. Quantitative results suggest that TWIN-CS has a core-and-periphery network structure with the Boston College design team at the innermost core, with visibly dense ties connecting to and from them. Most teachers, on the other hand, occupy the most peripheral positions in this network. Survey evidence also showed that participants generally perceived a much stronger learning relationship within schools and showed less certainty on cross-network relationships. In terms of learning characteristics, majority of the respondents viewed knowledge sharing, trust, and advice-oriented dimensions “strongly” but perceived a lack of data-driven learning for both within school and cross-network. I conclude this study with a discussion of implications for future research and practice. / Thesis (PhD) — Boston College, 2016. / Submitted to: Boston College. Lynch School of Education. / Discipline: Educational Research, Measurement and Evaluation.

Les liens optiques permettent de disséminer une fréquence de référence ultra-stable à de nombreux laboratoires de recherche pour des mesures de très haute précision en métrologie et au-delà. Nous avons démontré premièrement une extraction simple d’un signal ultra-stable en différents points d’une liaison optique urbaine de 92 km, avec une stabilité de fréquence relative à 1 s de 1, 3 × 10−15 et sensiblement dégradée sur le long terme par les effets thermiques diurnes. Nous avons développé et testé un deuxième dispositif amélioré avec un montage interférométrique compact et activement thermalisé et une diode laser permettant de disséminer le signal vers un lien secondaire dont le bruit est activement compensé. Ces deux dispositifs permettront de disséminer le signal à de multiples utilisateurs en région parisienne et sur le réseau REFIMEVE+. Nous avons deuxièmement évalué les performances d’une méthode de type Two-Way pour la comparaison de deux références de fréquence par fibre optique. Nous avons testé la sensibilité de cette comparaison sur une boucle fibrée de télécommunication de 100 km en propagation unidirectionnelle puis bidirectionnelle, avec une excellente stabilité de la fréquence grâce à une très bonne réjection du bruit de la fibre. Ces résultats ouvrent la voie à la réalisation d’un réseau métrologique à l’échelle nationale et internationale pour la dissémination des meilleures horloges optiques. / Optical frequency links give the possibility to disseminate an ultra-stable frequency reference to many research laboratories for precise measurements as performed in frequency metrology and in applied and fundamental physics. We demonstrated first a simple branching network setup dropping an ultra-stable signal at different positions along an urban optical link of 92 km, that exhibits a relative frequency stability of 1.3×10−15 at 1 s integration time, limited by long-term diurnal thermal effects. We developed and tested an improved setupwith a compact and thermalized optical interferometer and a laser diode used to feed a secondary link, which fiber noise is compensated. These two setup open the way to multiple-users dissemination in Paris area and on the REFIMEVE+ network.Second we demonstrated optical frequency comparison using a two-way method. We tested the sensitivity of this comparison over a 100 km telecommunication fiber loop network using either unidirectional or bidirectional propagation, with an excellent frequency stability thanks to the very good rejection of the fiber noise.These results open the way to high-resolution frequency comparison of the best optical clocks over national or international fiber networks.

In two-way radio systems, talk groups are used to organize communication. Some situations may call for creating a temporary talk group, but there are no straightforward ways to do this. Making a new talk group requires programming radios off-line. Temporary groups can be created, but this requires inputting radio IDs which is tedious on a radio's limited controls. By describing group members using attributes, ciphertext-policy attribute-based encryption (CP-ABE) can be used to quickly create sub-groups of a talk group. This scheme requires fewer button presses and messages sent in the new talk group are kept secret. CP-ABE can be used on deployed hardware, but performance varies with the type of embedded processor and the number of attributes used. Because radio communication is time-critical, care must be taken not to introduce too much audio delay. By using benchmark programs on a variety of single-board computers, we explore the limits of using CP-ABE on a two-way radio.

In order to investigate the thermal stress and expansion as well as the associated strain effect on material properties caused by high temperature and large temperature gradient, a two-way thermo-mechanical coupling solver is developed. This solver integrates a new structural response module to the Kentucky Aerothermodynamics and Thermal response System (KATS) framework. The structural solver uses a finite volume approach to solve either hyperbolic equations for transient solid mechanics, or elliptic equations for static solid mechanics. Then, based on the same framework, a quasi-static approach is used to couple the structural response and thermal response to estimate the thermal expansion and stress within Thermal Protection System (TPS) materials. To better capture the thermal expansion and study its impacts on material properties such as conductivity and porosity, a moving mesh scheme is also developed and incorporated into the solver. Grid deformation is transferred among different modules in the form of variations of geometric parameters and strain effects. By doing so, a bi-direction information loop is formed to accomplish the two-way strong thermo-mechanical coupling. Results revealed that the thermal stress experienced during atmospheric re-entry concentrates in a banded area at the edge of the pyrolysis zone and its magnitude can be large enough to cause the failure of the TPS. In addition, thermal expansion causes the whole structure to deform and the changes in material properties. Results also indicated that the impacts coming from structural response should not be ignored in thermal response.

Quantitative data examined the effectiveness of a Two Way Bilingual Immersion program on the biliteracy and academic achievement of elementary English learners in southern California. Scores from the California Standards Test (CST) for language arts and mathematics were used to compare the effects of a bilingual curriculum on Hispanic English learners and Hispanic English Only Speakers. English learners' average group scores increased significantly; average group scores for English Only Students' decreased. The Standards Test in Spanish (STS) scores indicate English learners' gains in biliteracy development. These notable academic outcomes evidence the importance of Two Way Bilingual Immersion program for English learners.