Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: A wet-cooling tower fill performance evaluation model developed by Reuter is derived in Cartesian coordinates for a rectangular cooling tower and compared to cross- and counterflow Merkel, e-NTU and Poppe models. The models are compared by applying them to a range of experimental data measured in the cross- and counterflow wet-cooling tower test facility at Stellenbosch University. The Reuter model is found to effectively give the same results as the Poppe method for cross- and counterflow fill configuration as well as the Merkel and e-NTU method if the assumptions as made by Merkel are implemented. A second order upwind discretization method is applied to the Reuter model for increased accuracy and compared to solution methods generally used to solve cross- and counterflow Merkel and Poppe models. First order methods used to solve the Reuter model and crossflow Merkel and Poppe models are found to need cell sizes four times smaller than the second order method to obtain the same results. The Reuter model is successfully implemented in two- and three-dimensional ANSYS-Fluent® CFD models for under- and supersaturated air. Heat and mass transfer in the fill area is simulated with a user defined function that employs a second order upwind method. The two dimensional ANSYS-Fluent® model is verified by means of a programmed numerical model for crossflow, counterflow and cross-counterflow. / AFRIKAANSE OPSOMMING: ‘n Natkoeltoring model vir die evaluering van pakkings werkverrigting, wat deur Reuter ontwikkel is, word in Kartesiese koördinate afgelei vir ‘n reghoekige koeltoring en word vergelyk met kruis- en teenvloei Merkel, e-NTU en Poppe modelle. Die verskillende modelle word vergelyk deur hulle op ‘n reeks eksperimentele data toe te pas wat in die kruis- en teenvloei natkoeltoring toetsfasiliteit by die Universiteit van Stellenbosch gemeet is. Dit is bevind dat die Reuter model effektief dieselfde resultate gee as die Poppe model vir kruis- en teenvloei pakkingskonfigurasies sowel as die Merkel en e-NTU metode, indien dieselfde aannames wat deur Merkel gemaak is geїmplementeer word. ‘n Tweede orde “upwind” metode word op die Reuter model toegepas vir hoër akkuraatheid en word vergelyk met oplossingsmetodes wat gewoonlik gebruik word om kruis- en teenvloei Merkel en Poppe modelle op te los. Eerste orde metodes wat gebruik is om die Reuter model en kruisvloei Merkel en Poppe modelle op te los benodig rooster selle wat vier keer kleiner is as vir tweede orde metodes om dieselfde resultaat te verkry. Die Reuter model is suksesvol in twee- en driedimensionele ANSYS-Fluent® BVD (“CFD”) modelle geїmplementeer vir on- en oorversadigde lug. Warmte- en massaoordrag in die pakkingsgebied word gesimuleer mbv ‘n gebruiker gedefinieerde funksie (“user defined function”) wat van ‘n tweede orde numeriese metode gebruik maak. Die tweedimensionele ANSYS-Fluent® model word m.b.v. ‘n geprogrameerde numeriese model bevestig vir kruis-, teen- en kruis-teenvloei.

Thesis (PhD (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2003. / The thermal performance prediction of wet-cooling towers is critically analyzed and refined. Natural draft counterflow towers and mechanical draft counterflow and crossflow towers are considered. The Merkel, Poppe and e-NTU heat and mass transfer methods of analysis are derived from first principles, as these methods form the cornerstone of wet-cooling tower performance evaluation. The critical differences between these methods, when applied to fill performance analyses and cooling tower performance evaluations, are highlighted. The reasons for these differences are discussed with the aid of psychrometric charts. A new extended empirical relation for the loss coefficient of fills is proposed where the viscous and form drag effects are accounted for as well as the buoyancy, momentum and fill height effects. The empirical equation for the transfer characteristic of fills is extended to include the effects of fill height and the inlet water temperature. Empirical equations to predict the temperature inversion profile, height of the temperature inversion and the height from which air is drawn into the cooling tower are developed. The influence of temperature and humidity inversions on the performance of wet-cooling towers is subsequently investigated. A comprehensive analytical computer program is developed to predict and optimize the performance of wet-cooling towers. Computer programs are also developed to generate cooling tower performance curves, analyze fill performance test data and plot psychrometric charts.

1990年代中期起，德國與中國均擺脫冷戰之羈絆而大步躍上國際舞台。德國統一後，國家實力大幅提升，並亟欲謀求與其身分相襯之國際地位。今年是柏林圍牆倒塌廿週年，據媒體報導，資料顯示，當時英國首相及法國總統還相當擔心德國統一後，強盛的德國會不會對世界帶來另一場世界的災難。而德國現任的總理梅克爾(Angela Merkel)自執政後，數年來已多次被知名媒體評選為全球最有影響力、權力的女性排行榜的首位，可見在她的領導下，德國的國力正逐漸恢復昔日的榮光。 今年亦正是大陸「六四天安門事件」發生後的廿年，中國從被國際孤立，再到當時的最高領導者以無比的魄力和眼光，推動並加速經濟改革開放進程，讓中國能夠在今天變成G2之一，迫使冷戰後世界僅存的超級強權美國，在許多國際事務上不得不尋求中國的支持與合作，足見中國的全球政經影響力已不可被漠視與忽視。 因此，西方世界的強國德國，面對正在崛起的強權中國，如何制定並推動其對中國的外交政策，以更進一步獲取德國的國家利益，在世界舞台上穩穩的佔有一席之地並有發言權及影響力，是德國的執政者念茲在茲、不可避免亦無法迴避的課題。 柯爾(Helmut Kohl)政府時代，基於清楚認知亞洲，特別是中國在未來世界發展中的重要性，德國在歐盟國家中首先醞釀和率先制訂新的亞洲政策，以實現德國在這一地區追求現實利益和戰略目標。施洛德(Gerhard Schröder)自1998年打敗柯爾接續執政後，任內6度訪問中國，對推動德中關係不遺餘力，將德國對中國的外交關係推上史無前例的新台階，被中國媒體稱為中國人民的老朋友、最受中國人歡迎的德國友人。德國的對中國外交政策已經出現新的微妙變化：致力於在中國推廣政治民主化、建設中國成為法治國家、經濟繁榮進步以使德國能從中國獲得經濟利益，成為當時德國政府的目標。 梅克爾(Angela Merkel)2005年接替施洛德政府執政以來，其對中國外交政策較前任施洛德政府時期再做出重大調整。從德國對中國貿易逆差、軍售問題到智慧財產權再到人權對話等領域，中國不斷感受到來自德國的壓力。尤以梅氏執政初期，德中兩國外交關係就因梅克爾在總理府接見達賴而引發喧然大波，後風波暫告平息，兩國關係才稍有回暖跡象。但要回到施洛德時代德、中兩國水乳般交融已不可能。但面對中國強大的經濟發展能力及廣大的市場，梅克爾政府對中國的外交政策，在不影響德國「貿易立國」宗旨的原則，另在世界「一超多強」格局的現有世界體系結構下，德國與中國之間保持這樣一種「經濟掛帥，政治跟進」的關係格局仍將是一個長期的現象。 發展德中良好關係符合德國的經濟利益。德國是中國在歐洲最大的貿易夥伴、是對中國技術轉讓最多的歐洲國家、是向中國提供政府貸款和無償贈款最多的歐洲國家，基於經濟利益，德國不會亦不願看見德國與中國雙邊關係出現僵局。 / From mid of 1990s, Germany and China both try to break apart from the restrain of the cold war. After the unity of German, its national power rises tremendously and hesitates to reach a matching international reputation. This year is the twenty anniversaries after the collapse of Berlin Wall. From the media report and statistic, the British prime minister and French president were worried if the unitized German would bring another worldwide disaster. Since the current prime minster of Germany, Angela Merkel, sworn in office, she has been rated as the most influential and powerful woman in the world. It could be said that under her leadership, Germany is recovering its past glory. This year is also the twenty year anniversary of the“Tiananmen Square protests of 1989”in mainland China, after that event, China was isolated from the international community; then, the highest leader of China pushed the reform of free market economy with unmatched vision and determination, and gave China the chance to become one of the G2 of Today. This force the only surviving super-power of the cold war, the United States, without any choice but to seek support and cooperation from China on many international issues, and it can be said that China’s influence in the international politics and economic cannot be denied or overlooked. As a result, the powerful Germany of the western world, facing the rising influential China, is challenged with the unavoidable task to plan and execute their diplomatic policies to mainland china in order to benefit the German, and secure their voice and influence in international affair- a privilege that German is not willing to yield ground. During the rule of Helmut Kohl government, German knew that the development of Asia, especially, China, would play a very important role in the future. Germany was the first country of the European union to make new Asia policy in order to realize the interest and strategic goal of Germany in this region. Since Gerhard Schröder defeated Helmut Kohl to gain office, he visited China six times in his term, and gave no reserve in developing Germany China relation, and pushed the diplomatic relation between China and Germany to a unprecedented level, and he was called by the Chinese media as an old friend to the Chinese people, and as “the most popular German friend of the Chinese people”. There are new subtle changes in Germany’s China policy: focusing on developing democracy in China, building China as a country with laws, facilitate economic growth of China for German to gain economic benefits. All of that was the goal for the German government. After Angela Merkel took charge from 2005, she made great adjustment toward German’s policies to China. Comparing to previous prime minister, she pressed hard on the trade deficit of German China trade, weapon trade, intellectual property rights and human rights. China never stop feeling the pressure from German. Especially in the earlier days, when Merkel’s term begun, the diplomatic relation between German and China turned sour when Merkel met Dalai Lama. Even though the argument got temporary ease, and the relation between two countries turns better, it is almost impossible to return the point when Schröder taking charge when the relation of two counties used to reach the peak. However, in front of Chinese strong economy development and its wild market, Merkel adapts the principle which not influences Germany trade as well as interacts with other countries. These days ‘economy weighs more than politics will still continue for long term. Developing a good relationship with China is beneficial for German. German is the largest partner of European countries for mainland China. Actually, it is the country that China transfers technical skills most. Also, it is the country that Chinese government provides loan and un-paid donation most. For the above reason, Germany government will not expect the relationship with China to turn bad based on economy enefit.

Taking off from a security related interest in de-democratization processes throughout Europe and the limited theoretical field thereof, this paper examines the political development in Poland 2008-2018. Through a comparison of the development in Poland and Hungary, the ambition is to identify what differs the de-democratization process of the two East European countries in regards to their communist past and in a broader sense to their current membership in the European Union. To guide the comparison is the theoretical framework of Merkel (2004), through both qualitative and quantitative analysis as it has been applied on Hungary by Bogaards (2018). The combined framework provides five categories of defect democracies: exclusive, illiberal, delegative, tutelary and diffusely defect. While Bogaards (2018) categorizes Hungary as a diffusely defect democracy, the study finds that Poland does not adhere to any single one of the categories. The question of what differs the development in Poland and Hungary is best answered in terms of legality. Whereas the systematic Hungarian process has been carried out within legal frames of the majority rule in parliament, the hasty Polish process resembles a palace revolution, as the leading party is interfering with and partly controlling the rule of law. The study provides support to the observations of the EU being an externally limiting, enabling and legitimizing factor of autocratic developments in member states, made by Bozóki and Hegedüs (2018). Additionally, a reverse snowball effect is being put to action by Poland and Hungary vetoing on EU sanctions against one another. The findings of the paper also support observation made of a limited research field; theoretical understanding and international measurement indexes of democratization being insufficient in explaining and describing the emerging de-democratization. The study opens up for further research regarding democratic peace in Europe.

Immer wieder fallen im Verlauf von Wahlkämpfen Schlagworte wie Personalisierung, Negativismus und Sensationalismus. Während diese Eigenschaften auf modern geführte Wahl-Kampagnen in den USA durchaus zutreffen mögen, so bescheinigen Studien deutscher Wahlforschungsinstitute für die Bundesrepublik doch recht durchwachsene Befunde. Im Zuge der Bundestagswahl 2005 haben wir uns mittels einer Inhaltsanalyse mit der Kandidatendarstellung Angela Merkels in der deutschen Qualitätspresse beschäftigt. Dabei ging es uns besonders um die Feststellung eines Wandels in der Darstellung Angela Merkels, welcher die Wähler in ihrer Wahlentscheidung beeinflusst haben könnte und um erkennbare Indizien für einen generellen Trend zur Personalisierung. / During electoral campaigns one can always hear key words like personalization, negativism and sensationalism. While these terms may represent the harsh reality of modern campaigns in the US, the results for Germany are rather ambiguous, according to prominent scientific studies. Following the chronology of the German 2005 election of the Bundestag, we tried to evaluate the presentation of candidate Angela Merkel, who ran for chancellor’s office, in the German quality press. Our main goal was the verification of a change in the way the papers presented Angela Merkel, hence possibly influencing the electorate. Furthermore, we tried to find proof of a general trend of personalization in Germany’s elections of 2005.

The aim of this thesis is to analyze the process of securitization of immigration and multiculturalism within the framework of migration, immigration and integration policies focusing on the case of Germany. Using the migration-security nexus as a primary theoretical foundation, I argue that within the policies and legislations related to immigration, German governments ultimately perceive immigration as a threat at the level of state security as well as Germany's national identity. The first government I have selected for my analysis is the cabinet led by Gerhard Schröder (1998 - 2005) who challenged the romanticized perception of the German nation as a "nation of descent" by saying that "Germany is a country of immigration." Secondly, I focus on the chancellorship of Angela Merkel whose approach toward the Syrian asylum seekers in the context of the current migration crisis (9/2015 - 11/2016) has been called "Wilkommenskutlur" (or "Welcome culture"). Nonetheless, by studying the policies related to immigration as well as governments' discourses, I argue that in both cases, immigration and multiculturalism are indeed linked to security issues. Hence, immigrants are perceived as a threat to Germany's national security and its identity.

This thesis examines selected political speeches with regard to word-formation and its processes, namely from the grammatical, semantic, and pragmatic points of view. The analyzed political speeches are the Otto von Bismarck's speech delivered on 20 July 1870, the Adolf Hitler's speech delivered on 1 September 1939, the Willy Brandt's speech delivered on 10 November 1989, and the Angela Merkel's speech from 14 December 2015. This is an interdisciplinary thesis which deals with politics, history, and linguistics. The thesis examines four different periods, namely Bismarck's era, Nazism, the Federal Republic of Germany between 1949 and 1990, and the contemporary Federal Republic of Germany. These periods are analyzed from the political, historical, and socio-cultural points of view. Subsequently, the selected political speeches are analyzed with respect to word- formation, its processes, and the period in which they were delivered. The individual results are then compared and certain conclusions are drawn from the comparison. The aim of this thesis is to highlight the importance of word-formation and its processes which are significant for political speeches from the 19th century onwards. This thesis shows and analyzes the motives, purposes, aims, and consequences of their usage in particular...

Le polyomavirus à cellules de Merkel est aujourd’hui reconnu comme l’agent étiologique du carcinome à cellules de Merkel (CCM). Le cycle viral et les mécanismes de l’oncogenèse viro-induite sont peu connus et les connaissances se basent essentiellement sur les études menées notamment sur le polyomavirus SV40. L’objectif des travaux de thèse était d’identifier les interactions entre les protéines virales et les protéines cellulaires lors de l’infection ou dans le contexte du carcinome à cellules de Merkel (CCM). Pour identifier ces interactions, nous avons réalisé des cribles double hybride en levures sur les oncogènes du MCPyV et du BKPyV. Afin valider les interactions obtenues en levures, nous avons utilisé une méthode orthogonale de validation par complémentation en cellules de mammifères reposant sur la restauration de la luciférase de Gaussia princeps. La combinaison de ses deux techniques nous a permis de valider des interactions avec des partenaires cellulaires impliqués dans la régulation du cycle cellulaire ou encore de la voie Akt-mTOR. Les précédents travaux du laboratoire, qui portaient sur l’interactome des protéines mineures de capsides VP2/VP3, avaient également permis d’identifier des interactions avec des protéines de la voie NF-kB. Nous avons alors testé les interactions entre les oncogènes et la protéine mineure de capside VP2 avec des protéines cellulaires impliquées dans cette voie. Ces travaux nous ont conduits à tester l’activation de la voie, l’expression des gènes sous le contrôle de NF-kB et la régulation de l’apoptose. Les résultats obtenus montrent une action de la protéine VP2 sur l’activation de la voie NF-kB et une induction de l’apoptose. / The Merkel cell polyomavirus is now recognized as the etiologic agent of Merkel cell carcinoma (MCC). The viral cycle and viro-induced oncogenesis mechanisms are not fully understood and the knowledge is mainly based on the studies carried out particularly on the SV40 polyomavirus. The aim of our work is to identify interactions between viral proteins and cellular proteins during productive infection or in MCC context. To identify these interactions, we performed yeast two hybrid screens on MCPyV and BKPyV oncogenes, as control. To validate the interactions obtained in yeasts, we used an orthogonal method of validation by complementation in mammalian cells based on the restoration of Gaussia princeps luciferase. The combination of these two orthogonal techniques allowed us to validate interactions with cellular partners involved in cell cycle regulation or Akt-mTOR pathway. Previous lab work on VP2/VP3 minor capsid proteins allowed the identification of interactions with NF-kB pathway involved proteins. We examined the interactions between oncogenes, VP2, with the cellular proteins involved in this pathway. This work led us to evaluate pathway activation, genes expression under the control of NF-kB and apoptosis regulation. These results evidenced an action of the VP2 protein on the activation of NF-kB pathway and an induction of apoptosis.

The diploma thesis examines the political narrative of German Chancellor Angela Merkel during the EU migration crisis in 2015-2016. The aim of the thesis is to show, how Chancellor Merkel justified her policy and the approach of the Federal government in matters of European migration policy. What priorities and motives can be seen in the keynote speeches of the German Chancellor? Which of the arguments were crucial? The thesis is based on the fact that Merkel took on two levels of argument. On the one hand, she understands her political actions in the European Union from a normative point of view, on the other hand some political steps could be seen from a pragmatic strategic point of view. The aim of the study is also to examine the role of Germany in the EU from the perspective of the so-called dividual actor. After the introductory section, the third chapter outlines the development of the migration crisis in the EU. The following chapter brings an overview of the solution to the migration crisis in terms of developments in Germany. The fifth chapter is an analytical part of the thesis, which aims to identify and interpret the various narratives of Angela Merkel in the field of German European policy and the solution to the migration crisis. In conclusion the results of analysis are introduced.