Ce travail, dont le titre est : Le modèle d’immersion réciproque en question : enseigner en classe bilingue à New York et à Francfort / Das Two-Way-Immersion Modell im Fokus : Zweisprachig unterrichten in New York und Frankfurt/Main, a pour objectif de répondre à la problématique suivante : comment la conceptualisation du modèle d’enseignement bilingue d’immersion réciproque influence les pratiques éducatives (didactiques et pédagogiques) des enseignants et les productions langagières des enfants, et pourquoi ? / The aim of this study, the title of which is “Focussing on the model of two-way immersion: teaching in bilingual classrooms in New York and Frankfurt on the Main”, is to provide an answer to the following question: in what ways does the conceptualisation of the bilingual model of two-way immersion affect the educational practices, both didactic and pedagogical, of teachers and the language production of children, and why is this so?

People often have very little knowledge about the impact of unsustainable human population growth on the environment and social well-being especially in developing countries. Therefore, an efficient method should be explored in order to educate, and if possible, to convince the members of the public to realize the environmental and social problems caused by the unsustainable population growth. Digital Game-Based Learning (DGBL) has been highlighted by some studies as an innovative tool for learning enhancement. While only a handful of studies have scientifically evaluated the impact of DGBL on knowledge outcomes, the approach is an attractive tool to increase knowledge and motivate engagement with environmental issues surrounding population growth because of its potential to improve learners’ motivation and engagement thereby compared to traditional learning approaches. Therefore, the three primary research questions for this study are: 1) "Can a single-player digital game be an appropriate and attractive learning application for the players to gain insight about the relationship between the growing human population and the environmental issues?" 2) "How can we design environmental games for the players to gain insights about the relationship between the growing human population and the environmental issues via playing a game?" and 3) "What are the obstacles preventing the players from adapting environmental knowledge obtained from the learning mediums into the real-life?" To inform the development of an efficacious DGBL game to impact learning outcomes, critical reviews of environmental issues related to population growth as well as critical reviews of commercial and serious environmental games in terms of their educational and motivational values were undertaken in this study. The results of these critical reviews informed the development of a Guideline for Environmental Games (or GEG). The GEG was developed by combining the engaging game technology with environmental learning and persuasion theories. The GEG was then used to inform the development of a prototype game called THE GROWTH; a single-player, quiz-based, city-management game targeting young adolescents and adults. Multiple evaluation methods of the game were used to answer the three key research questions mentioned earlier. These methods included: 1) The Randomized Controlled Trial approach (RCT) where the participants were systematically divided into the experimental and the control group respectively and their knowledge scores (quantitative data) compared and analyzed, 2) The participants’ abilities to recall and describe the environmental and well-being issues were collected and analyzed qualitatively using The Content Analysis method (CA) and, 3) The participants’ overall feedback on the learning mediums was collected and analyzed to evaluate the motivational values of THE GROWTH itself. To this end, THE GROWTH was evaluated with 82 Thai-nationality participants (70 males and 12 females). The results showed that participants assigned to play THE GROWTH demonstrated greater environmental and social-well-being knowledge related to population growth (F(1,40) = 43.86, p = .006) compared to the control group participants assigned to a non-interactive reading activity (consistent with material presented in THE GROWTH). Furthermore, participants who played THE GROWTH recalled on average more content presented in the game when compared to participants who were presented with similar content in the reading material (t (59) = 3.35, p = .001). In terms of level of engagement, the study suggested that participants assigned to the game were more engaging with their learning medium on average when compared to participants assigned to the non-interactive reading activity. This is evidenced by the longer time participants spent on the task, the activity observed from participants’ recorded gameplay, and their positive responses in the survey. The semi-structured interviews used in this study highlighted the participants’ attitudes towards the environmental, social, and technological issues. Although the participants’ perceived behavioural intention towards the environmental commitments were not statistically differed between the two study group, their responses still provide some evidences that leaps may occur from the learning mediums to the real-world context. Furthermore, these responses can be valuable evidences for the policy makers and for the future development of environmental serious games. Overall, the results suggested that digital environmental games such as THE GROWTH might be an effective and motivational tool in promote the learning about sustainable population size, the environment, and the social well-being. The game’s ability to convince the participants to change towards sustainable lifestyles, however, might be subjected to the future research and other real-world circumstances such as the governmental and public supports. In summary, the research in this thesis makes the following contributions to knowledge: • The Guideline for Environmental Games (GEG) contributes to knowledge about making theoretically-based environmental games. It has particular significance because the guideline was validated by demonstrating learning improvements in a systematic randomized controlled trial. • The use of Multi-Strategy Study Design where multiple systematic evaluation methods were used in conjunction to provide conclusive findings about the efficacy of DGBL to impact outcomes. • THE GROWTH itself is a contribution to applied research as an example of an effective DGBL learning tool.

Text in English, abstract in English, Afrikaans and Venda / This study developed and tested an integrated internal communication audit (IICA) tool to evaluate the communication strengths and weaknesses of the Unisa Library. The existing communication audit instruments were explored, namely: the Communication Satisfaction Questionnaire (CSQ) and the International Communication Association (ICA) audit were adapted and complemented by the Organisational Culture Survey (OCS) and the Critical Incident Technique (CIT). The current trends and the trends in South Africa were also explored. The sequential mixed method design consisting of the semi-structured qualitative interviews and the quantitative surveys were used to collect data. The ATLAS.ti and the Statistical Package for Social Sciences (SPSS) software packages were used to analyse qualitative and quantitative data. The results revealed the IICA as an appropriate tool for measuring the integrated internal communication of the Unisa Library. The IICA identified the communication needs of employees; the active and preferred communication channels; and the positive and negative communication experiences of employees. / Hierdie studie het ʼn geïntegreerde interne kommunikasie-oudit (IICA)-hulpmiddel ontwikkel en getoets om kommunikasie-sterkpunte en -swakhede van die Unisa-biblioteek te evalueer. Die bestaande kommunikasie-oudit-instrumente was ondersoek, naamlik: die Kommunikasietevredenheidsvraelys (CSQ) en die Internasionale Kommunikasievereniging (ICA) se oudit is aangepas en gekomplementeer deur die Organisasiekultuur-opname (OCS) en die Kritiese-insident-tegniek (CIT). Die sekwensiële gemengdemetode-ontwerp, bestaande uit die halfgestruktureerde kwalitatiewe onderhoude en die kwantitatiewe opnames, is gebruik om data in te samel. Die ATLAS.ti-programmatuurpakket en die Statistiese Pakket vir Sosiale Wetenskappe (SPSS)-programmatuur is gebruik om kwalitatiewe en kwantitatiewe data te ontleed. Die resultate gewys die IICA as ʼn geskikte hulpmiddel was in die meting van die geïntegreerde interne kommunikasie van die Biblioteek. Die IICA geïdentifiseer die kommunikasie behoeftes van werknemers; die aktiewe en voorkeur kommunikasie kanale; en die positiewe en negatiewe kommunikasie ervarings van werknemers. / Ngudo iyi yo bveledza na u linga tshishumiswa tsha u Sedzulusa Vhudavhidzani ha nga ngomu ho Ṱanganelaho (Integrated Internal Communication Audit (IICA), u ṱola vhuḓi na vhuvhi ha vhudavhidzani kha Ḽaiburari ya Univesithi ya Afrika Tshipembe. Zwishumiswa zwa u sedza vhudavhidzani zwi re hone zwo sedzuluswaho zwi katela: Mbudzisambekanywa dza Vhudavhidzani dzine dza fusha ṱhoḓea (Communication Satisfaction Questionnaire) (CSQ) na tshishumiswa tsha u sedzulusa vhudavhidzani tsha Dzangano ḽa Dzitshaka ḽa Vhudavhidzani (International Communication Association) (ICA). Zwishumiswa izwo zwo ḓadziswa nga tshishumiswa tsha Ṱhoḓisiso ya Mvelele ya Tshiimiswa (Organisational Culture Survey) (OCS) na Tshikalo tsha u ela Maitele a Zwithu zwa ndeme (Critical Incident Technique) (CIT). Pulane ya thevhekano ya maitele o ṱanganelaho o vhumbwaho nga maitele a ṱhoḓisiso ane a shumiswa kha saintsi dza matshilisano (qualitative) na maitele a ṱhoḓisiso ane a shumisa zwiṱatisiṱika na mbalo (quantitative) zwo shumiswa u kuvhanganya mawanwa. Phakhedzhi ya Sofuthiwea ya ATLAS.ti na phakhedzhi ya Siṱatisiṱika ya Saintsi dza Matshilisano (Statistical Package for Social Sciences - SPSS) dzo shumiswa u saukanya mawanwa a ṱhoḓisiso dza matshilisano na a ṱhoḓisiso dza zwiṱatisiṱika na mbalo. Mvelelo dzo bvisela khagala uri IICA ndi tshishumiswa tsho teaho u ela vhudavhidzani ho ṱanganelaho ha nga ngomu Ḽaiburari ya Univesithi ya Afrika Tshipembe. Tshishumiswa itshi tsho bvisela khagala thoḓea dza vhashumi dza vhudavhidzani, zwishumiswa zwa vhudavhidzani zwine zwa khou shumiswa na zwi takalelwaho; na tshenzhemo ya vhashumi kha vhudavhidzani havhudi and vhu si havhudi. / Communication Science / M. Comm (Communication Science)

In den letzten Jahrzehnten sind Satellitennavigationssysteme zu einem unverzichtbaren Teil des modernen Lebens geworden. Viele innovative Anwendungen bieten ortsabhängige Dienste an, welche auf diesen Navigationssystemen aufbauen. Allerdings sind diese Dienste in Innenräumen nicht verfügbar. Daher werden seit einigen Jahren alternative Lokalisierungsmethoden für Innenräume aktiv erforscht und entwickelt. Der Schwerpunkt dieser Arbeit liegt darauf, die Genauigkeit von Lokalisationsmethoden in Innenräumen zu erhöhen, sowie auf der effektiven Integration der entsprechenden Verfahren in drahtlose Kommunikationssysteme. Es werden zwei Ansätze vorgeschlagen und untersucht, welche die Präzision von ToF-basierten Methoden erhöhen. Zum einen wird im „Modified Equivalent Time Sampling“ (METS) Verfahren eine überabgetastete Version der vom Radioempfänger gelieferten Wellenform erzeugt und zur ToF Bestimmung verwendet. Der zweite erforschte Ansatz hat zum Ziel, Fehler auf Grund von Taktfrequenz-Abweichungen zu kompensieren. Dieses ist für kooperative Lokalisationsmethoden (N-Way ranging) von Bedeutung. Das in der Arbeit entwickelte Verfahren führt zu einer erheblichen Reduzierung der Fehler in der Abstandsmessung und damit der Positionsbestimmung. Darüber hinaus wurde eine neue Methode untersucht, um Lokalisationsverfahren in Funksysteme für die ISM Bänder bei 2,4 GHz und 5 GHz zu integrieren. Die Methode wurde auf einer Software Defined Radio (SDR) Plattform implementiert und bewertet. Es konnte eine Genauigkeit bis zu einem Meter in der Positionsbestimmung demonstriert werden. Schließlich wurde ein Verfahren vorgeschlagen und untersucht, mit welchem Lokalisationsfähigkeit in bestehende Funksysteme integriert werden kann. Die betrachtete Methode wurde in einem 60 GHz Funksystem mit hoher Datenrate implementiert. Die Untersuchungen zeigten eine Positionsgenauigkeit von 1 cm bei einer gleichzeitig hohen Datenrate für die Übertragung von Nutzdaten. / In the last couple of decades the Global Navigation Satellite Systems (GNSS) have become a very important part of our everyday life. A huge number of applications offer location based services and navigation functions which rely on these systems. Nevertheless, the offered localization services are not available indoors and their performance is significantly affected in urban areas. Therefore, in the recent years, a large number of wireless indoor localization systems are being actively investigated and developed. The main focus of this work is on improving precision and accuracy of indoor localization systems, as well as on the implementation and integration of localization functionality in wireless data transmission systems. Two approaches for improving the localization precision and accuracy of ToF based methods are proposed. The first approach, referred to as modified equivalent time sampling (METS) is used to reconstruct an oversampled versions of the waveforms acquired at the radio receiver and used for ToF based localization. The second proposed approach is used to compensate the ranging error due to clock frequency offset in cooperative localization schemes like N-Way ranging. This approach significantly reduces the ranging and, therefore, localization errors and has much better performance compared to the existing solutions. An approach for implementation of localization system in the 2.4/5 GHz ISM band is further proposed in this work. This approach is implemented and tested on a software defined radio platform. A ranging precision of better than one meter is demonstrated. Finally, an approach for integrating localization functionality into an arbitrary wireless data transmission system is proposed. This approach is implemented in a 60 GHz wireless system. A ranging precision of one centimeter is demonstrated.

The transport or the separation of solid particles or droplets suspended in a fluid flow is a common task in mechanical and process engineering. To improve machinery and physical processes (e.g. for coal combustion, reduction of NO_x and soot) an optimization of complex phenomena by simulation applying the fundamental conservation equations is required. Fluid-particle flows are characterized by the ratio of density of the two phases gamma=rho_P/rho_F, by the Stokes number St=tau_P/tau_F and by the loading in terms of void and mass fraction. Those numbers (Stokes number, gamma) define the flow regime and which relevant forces are acting on the particle. Dependent on the geometrical configuration the particle-wall interaction might have a heavy impact on the mean flow structure. The occurrence of particle-particle collisions becomes also more and more important with the increase of the local void fraction of the particulate phase. With increase of the particle loading the interaction with the fluid phase can not been neglected and 2-way or even 4-way coupling between the continous and disperse phases has to be taken into account. For dilute to moderate dense particle flows the Euler-Lagrange method is capable to resolve the main flow mechanism. An accurate computation needs unfortunately a high number of numerical particles (1,...,10^7) to get the reliable statistics for the underlying modelling correlations. Due to the fact that a Lagrangian algorithm cannot be vectorized for complex meshes the only way to finish those simulations in a reasonable time is the parallization applying the message passing paradigma. Frank et al. describes the basic ideas for a parallel Eulererian-Lagrangian solver, which uses multigrid for acceleration of the flow equations. The performance figures are quite good, though only steady problems are tackled. The presented paper is aimed to the numerical prediction of time-dependend fluid-particle flows using the simultanous particle tracking approach based on the Eulerian-Lagrangian and the particle-source-in-cell (PSI-Cell) approach. It is shown in the paper that for the unsteady flow prediction efficiency and load balancing of the parallel numerical simulation is an even more pronounced problem in comparison with the steady flow calculations, because the time steps for the time integration along one particle trajectory are very small per one time step of fluid flow integration and so the floating point workload on a single processor node is usualy rather low. Much time is spent for communication and waiting time of the processors, because for cold flow particle convection not very extensive calculations are necessary. One remedy might be a highspeed switch like Myrinet or Dolphin PCI/SCI (500 MByte/s), which could balance the relative high floating point performance of INTEL PIII processors and the weak capacity of the Fast-Ethernet communication network (100 Mbit/s) of the Chemnitz Linux Cluster (CLIC) used for the presented calculations. Corresponding to the discussed examples calculation times and parallel performance will be presented. Another point is the communication of many small packages, which should be summed up to bigger messages, because each message requires a startup time independently of its size. Summarising the potential of such a parallel algorithm, it will be shown that a Beowulf-type cluster computer is a highly competitve alternative to the classical main frame computer for the investigated Eulerian-Lagrangian simultanous particle tracking approach.

The North-West University (NWU) is an example of an organization that has a social responsibity towards the community and the environment within which it finds itself (Van Schalkwyk, 2013). One of the social responsibility programmes of the NWU-Pukke is known as the Students’ Rag Community Service (SRCS). The SRCS is a registered NPO (non-profit organization) which is run by the students of the NWU Potchefstroom Campus and which has been in existence since 1992 in its present form. In this study it is argued that the SRCS developmental projects could be offered in a more effective and sustainable manner by implementing the basic principles of the participatory approach, viz. Participation, dialogue, empowerment and cultural identity in order to support the local communities in their developmental processes. For the present study the focus was solely on one of the SRCS projects, the Pick a leader-leadership development project. This project has the aim of providing in the developmental needs of ten to fifteen Grade 11 learners in three schools in the North West Province (Potchefstrom and the surrounding communities in Ikageng). Thus project participants (learners) are instructed in basic skills about starting their own businesses (entrepreneurship); how to develop their leadership skills and to apply these skills, and how to be able to use basic life skills in their everyday lives. Various theoreticians have explained how NPO’s without participatory communication are seldom successful in terms of developmental initiatives. The learners can only develop if the relevant roleplayers of the project take ownership of the project by also being able to communicate in a participatory manner about their specific needs with both the NPO and the project volunteers. The NWU-Pukke volunteers, who manage this particular project, therefore have the responsibility to communicate in a participatory manner with the relevant learners, their teachers and then also the different principals to make the project succeed and to contribute to the realization of the developmental needs of the learners. The general research aim of the study had been to determine the nature of the communication among interest groups in the Pick a leader-leadership development programme of the SRCS. Qualitiative research methods, viz. Semi-structured interviews, focus group interviews and participant observation, were used in this study for purposes of making making a thorough investigation into the nature of the communication among those involved in the Pick a leader leadership development programme. The purpose of this was to determine perspectives about the project held by the persons involved (but especially those of the learners) and to interpret these in line with the normative theoretical principles of the participatory approach to developmental communication. It was ultimately found that the communication in the Pick a leader-leadership development programme was mostly one-way. / MA (Communication Studies), North-West University, Potchefstroom Campus, 2014

Theorists and management in the South African non-profit sector agree that strong stakeholder relationships are essential in negotiating the challenges faced by the South African non-profit sector. Despite the acknowledgement from the non-profit sector that strong relationships are key to achieving organisational goals, there is an apparent lack of knowledge and strategic thinking amongst them pertaining to the concept of stakeholder relationship management. Against this background the purpose of this study was therefore to develop a metamodern model for stakeholder relationship management, aimed specifically at the South African non-profit sector, that could be implemented by NPO management in a practical manner. The blurring lines between the opposing views of modernism versus postmodernism motivated the choice of metamodernism as a relevant worldview for this study. Metamodernism does not imply a balance between these poles, but rather a constant swinging of the pendulum during which metamodernism negotiates between modernism and postmodernism. It is the construction of a workable, interrelated worldview, recognising the intimate relationship between modernism and postmodernism. It was therefore concluded that a metamodern worldview in which both modernism and postmodernism feature, would not only make it possible for nonprofit organisation managers to understand and join the discussion on stakeholder relationship management, but also to implement the proposed metamodern stakeholder relationship management model. The resultant metamodern stakeholder relationship management model for non-profit organisations is framed by so-called modernistic communication and stakeholder relationship management theories, but it was done in line with the metamodern worldview of the study, allowing for initiative and innovation. The flexible, organic and cyclic nature of the proposed model echoes this worldview. A qualitative, exploratory and interpretative research design was implemented to test a conceptual framework and face-to-face semi-structured interviews were conducted with senior management in the non-profit sector. The design of the framework and subsequent model was guided by a number of assumptions and propositions arising from a thorough literature review, all of which were supported and confirmed by the research results. The most significant contribution of the study is the application of a metamodern worldview emanating from a reluctance to choose between a modern or postmodern stance when discussing communication science and stakeholder relationship management practices. It is therefore foreseen that it would offer the field of communication science new and creative means of combining modernism and postmodernism approaches when studying communication phenomena. It will also expand the responsibility for communication and stakeholder relationship management beyond that of the communication specialists to senior management in the non-profit sector. / Communication Science / D. Litt. et Phil. (Communication)

How do young adult students communicate through their smartphones today? Which applications and features do they choose? What motivates their choices for the various possible situations? In this paper we investigate which communication channels young adult students in Sweden use for private message communication in their smartphones, in what way they use the channels and why they choose specific channels for different types of communication. In Sweden today, there are numerous of different ways of communicate through smartphones. We have interviewed ten Swedish young adult students regarding their use. The results speaks for that SMS has proven to still be used very frequently, even though it has existed for many years and that there are plenty of other ways to communicate through private messages today. Social media, primarily Facebook, also attracts users to communicate through private messages with their smartphones. SMS isn’t any longer the obvious method for sending a message. By presenting the result of our study, we hope to provide for future design resolutions and to give the next generation of smartphones communication tools that are as optimal as possible.

我國近年勞工意識抬頭，受雇者日漸重視自身工作權益，罷工運動頻傳，其中，工會理事表示，過去上對下的單向考評制度並不公平，因此，工會所訴求之員工績效評估方式，不再只是主管打員工的考績，而是雙向評估，亦即，員工亦打主管的考績。會計師事務所為服務型組織，成敗基於人，故衡量成員之績效相當重要。因此，本文以其員工之績效評估為例，探討其適當之績效評估制度為何。本研究以問卷方式蒐集資料，並以我國大專院校之會計系、所學生為受測對象。透過情境設計，結合不同績效評估制度，以了解並推論會計師事務所員工對向上績效評估制度公平程度之認知。本研究之結論有二，第一，會計師事務所員工對績效評估制度公平程度之認知，會受到向上績效評估影響，且在有向上績效評估時，認為績效評估制度比較公平。第二，向上績效評估結果是否納入受評主管之年底績效，會影響員工對績效評估制度公平程度之認知，且當該結果納入績效時，員工認為績效評估制度比較公平。易言之，當向上績效評估結果無法直接影響受評主管之年底績效，員工仍認為事務所之績效評估制度有欠公平。 / Labor consciousness is rising in recent years, and labor are paying more and more attention to their interest. The director of a labor union after one striking activity pointed out that the traditional (top-down) performance evaluation approach is unfair, and requested for a two-way performance evaluation approach, that is, subordinate also evaluate the performance of their supervisor in addition to the traditional way. This research studies the performance evaluation system of accounting firm, for it is a service organization, it’s very important to measures the performance of members, and establishing an appropriate performance evaluation system is an continuing challenge for them. To infer the perception regarding the fairness of performance evaluation of the staff of the accounting firm, the research uses method of questionnaire survey to collect data, a combination of different performance evaluation systems with designed context is embedded in the questionnaire. Students of the department of accounting of universities participate in the experiment. There are two findings. First, the perception of fairness of performance evaluation system by the staff of the accounting firm will be affected by the upward appraisal system. Moreover, the performance evaluation system will be considered fair when there is an upward appraisal system. Second, the staff’s perception of fairness of performance evaluation system will also be affected if the results of upward appraisal system is counted as the performance of the supervisor. Furthermore, the performance evaluation system will be considered fair when the results of upward appraisal system will be counted as the supervisor’s performance. In other words, the performance evaluation system will be considered unfair if the results of upward appraisal system have no direct impact on the supervisor’s performance.

Les écoulements en eau peu profonde se rencontrent dans de nombreuses situations d’intérêts : écoulements de rivières et dans les lacs, mais aussi dans les mers et océans (courants de marée, tsunami, etc.). Ils sont modélisés par un système d’équations aux dérivées partielles, où les inconnues sont la vitesse de l’écoulement et la hauteur d’eau. On peut supposer que la composante verticale de la vitesse est petite devant les composantes horizontales et que ces dernières sont indépendantes de la profondeur. Le modèle est alors donné par les équations de shallow water (SWEs). Cette thèse se concentre sur la conception d’une nouvelle technique d’interaction de plusieurs grilles imbriquées pour modèle en eau peu profonde en utilisant des méthodes numériques. La première partie de cette thèse comprend, La dérivation complète de ces équations à partir des équations de Navier- Stokes est expliquée. Etudier le développement et l’évaluation des méthodes numériques en utilisant des méthodes de différences finies et plusieurs exemples numériques sont appliqués utilisant la condition initiale du niveau gaussien pour 2DSWEs. Dans la deuxième partie de la thèse, nous sommes intéressés à proposer une nouvelle technique d’interaction de plusieurs grilles imbriquées pour résoudre les modèles océaniques en utilisant quatre choix des opérateurs de restriction avec des résultats de haute précision. Notre travail s’est concentré sur la résolution numérique de SWE par grilles imbriquées. A chaque niveau de résolution, nous avons utilisé une méthode classique de différences finies sur une grille C d’Arakawa, avec un schéma de leapfrog complété par un filtre d’Asselin. Afin de pouvoir affiner les calculs dans les régions perturbées et de les alléger dans les zones calmes, nous avons considéré plusieurs niveaux de résolution en utilisant des grilles imbriquées. Ceci permet d’augmenter considérablement le rapport performance de la méthode, à condition de régler efficacement les interactions (spatiales et temporelles) entre les grilles. Dans la troisième partie de cette thèse, plusieurs exemples numéériques sont testés pour 2DSWE avec imbriqués 3:1 et 5:1. Finalement, la quatrième partie de ce travail, certaines applications de grilles imbriquées pour le modèle tsunami sont présentées. / Most flows in the rivers, seas, and ocean are shallow water flow in which the horizontal length andvelocity scales are much larger than the vertical ones. The mathematical formulation of these flows, so called shallow water equations (SWEs). These equations are a system of hyperbolic partial differentialequations and they are effective for many physical phenomena in the oceans, coastal regions, riversand canals. This thesis focuses on the design of a new two-way interaction technique for multiple nested grids 2DSWEs using the numerical methods. The first part of this thesis includes, proposing several ways to develop the derivation of shallow water model. The complete derivation of this system from Navier-Stokes equations is explained. Studying the development and evaluation of numerical methods by suggesting new spatial and temporal discretization techniques in a standard C-grid using an explicit finite difference method in space and leapfrog with Robert-Asselin filter in time which are effective for modeling in oceanic and atmospheric flows. Several numerical examples for this model using Gaussian level initial condition are implemented in order to validate the efficiency of the proposed method. In the second part of our work, we are interested to propose a new two-way interaction technique for multiple nested grids to solve ocean models using four choices of higher restriction operators (update schemes) for the free surface elevation and velocities with high accuracy results. Our work focused on the numerical resolution of SWEs by nested grids. At each level of resolution, we used explicit finite differences methods on Arakawa C-grid. In order to be able to refine the calculations in troubled regions and move them into quiet areas, we have considered several levels of resolution using nested grids. This makes it possible to considerably increase the performance ratio of the method, provided that the interactions (spatial and temporal) between the grids are effectively controlled. In the third part of this thesis, several numerical examples are tested to show and verify twoway interaction technique for multiple nested grids of shallow water models can works efficiently over different periods of time with nesting 3:1 and 5:1 at multiple levels. Some examples for multiple nested grids of the tsunami model with nesting 5:1 using moving boundary conditions are tested in the fourth part of this work.