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Fases geométricas, quantização de Landau e computação quâantica holonômica para partículas neutras na presença de defeitos topológicosBakke Filho, Knut 06 August 2009 (has links)
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Previous issue date: 2009-08-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / We start this work studying the appearance of geometric quantum phases as in the relativistic
as in the non-relativistic quantum dynamics of a neutral particle with permanent
magnetic and electric dipole moment which interacts with external electric and magnetic
fields in the presence of linear topological defects. We describe the linear topological
defects using the approach proposed by Katanaev and Volovich, where the topological
defects in solids are described by line elements which are solutions of the Einstein's equations
in the context of general relativity. We also analyze the in
uence of non-inertial
effects in the quantum dynamics of a neutral particle using two distinct reference frames
for the observers: one is the Fermi-Walker reference frame and another is a rotating frame.
As a result, we shall see that the difference between these two reference frames is in the
presence/absence of dragging effects of the spacetime which makes its in
uence on the
phase shift of the wave function of the neutral particle. In the following, we shall use our
study of geometric quantum phases to make an application on the Holonomic Quantum
Computation, where we shall show a new approach to implement the Holonomic Quantum
Computation via the interaction between the dipole moments of the neutral particle
and external fields and the presence of linear topological defects. Another applications for
the Holonomic Quantum Computation is based in the structure of the topological defects
in graphene layers. In the presence of topological defects, a graphene layer shows two
distinct phase shifts: one comes from the mix of Fermi points while the other phase shift
comes from the topology of the defect. To provide a geometric description for each phase
shift in the graphene layer, we use the Kaluza-Klein theory where we establish that the
extra dimension describes the Fermi points in the graphene layer. Hence, we can implement
the Holonomic Quantum Computation through the possibility to build cones and
anticones of graphite in such way we can control the quantum
uxes in graphene layers.
In the last part of this work, we study the Landau quantization for neutral particles as in
the relativistic dynamics and non-relativistic dynamics. In the non-relativistic dynamics,
we study the Landau quantization in the presence of topological defects as in an inertial
as in a non-inertial reference frame. In the relativistic quantum dynamics, we start our
study with the Landau quantization in the Minkowisky considering two different gauge
fields. At the end, we study the relativistic Landau quantization for neutral particles in
the Cosmic Dislocation spacetime. / Neste trabalho estudamos inicialmente o surgimento de fases geometricas nas dinâmicas quânticas relativística e não-relativística de uma partícula neutra que possui momento de
dipolo magnético e elétrico permanente interagindo com campos elétricos e magnéticos externos
na presença de defeitos topológicos lineares. Para descrevermos defeitos topológicos
lineares usamos a aproximação proposta por Katanaev e Volovich, onde defeitos lineares em sólidos são descritos por elementos de linha que são soluções das equações de Einstein
no contexto da relatividade geral. Analisamos também a
inuência de efeitos não-inerciais na dinâmica quântica de uma partícula neutra em dois tipos distintos de referenciais para
os observadores: um é o referencial de Fermi-Walker e outro é um referencial girante.
Vemos que a diferença entre dois referenciais está na presença/ausência de efeitos de arrasto
do espaço-tempo que irá influenciar diretamente na mudança de fase na funçãao de
onda da partícula neutra. Em seguida, usamos nosso estudo de fases geométricas para
fazer aplicações na Computação Quântica Holonômica onde mostramos uma nova maneira de implementar a Computação Quântica Holonômica através da interação entre momentos
de dipolo e campos externos e pela presença de defeitos topológicos lineares. Outra
aplicação para a Computação Quântica Holonômica está baseada na estrutura de defeitos
topológicos em um material chamado grafeno. Na presença de defeitos topológicos lineares,
esse material apresenta duas fases quânticas de origens distintas: uma da mistura
dos pontos de Fermi e outra da topologia do defeito. Para dar uma descrição geométrica para a origem de cada fase no grafeno usamos a Teoria de Kaluza-Klein, onde a dimensão extra sugerida por esta teoria descreve os pontos de Fermi no grafeno. Portanto, a implementação da Computação Quântica Holonômica no grafeno está baseada na possibilidade
de construir cones e anticones de grafite de tal maneira que se possa controlar os fluxos
quânticos no grafeno. Na última parte deste trabalho estudamos a quantização de Landau
para partículas neutras tanto na dinâmica não-relativística quanto na dinâmica relativística. Na dinâmica não-relativítica, estudamos a quantização de Landau na presença
de defeitos em um referecial inercial e, em seguida, em um referencial nãoo-inercial. Na
dinâmica relativística, estudamos inicialmente a quantização de Landau no espaço-tempo
plano em duas configurações de campos diferentes. Por fim, estudamos a quantização de
Landau relativística para partículas neutras no espaço-tempo da deslocação cósmica.
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臺北市國民小學組織再造之研究陳宜敏 Unknown Date (has links)
「國民中小學組織再造及人力規劃試辦方案」政策主要是為了配合九年一貫
課程實施,重視學校本位課程,期透過總量員額管制、調整國民小學組織與人力架構,促進教學與行政責任,期能減輕教師教學及行政負擔,並發揮教育經費使用效益。本研究旨在瞭解臺北市國民小學參與國民小學組織再造與人力試辦規劃方案實施情形與成效、探討臺北市國民小學教師對於國民中小學組織再造與人力規劃試辦方案之認知程度與支持度、瞭解臺北市國民小學教師對於學校滿意度與學校組織規劃之意見。採用文件分析法與問卷調查法二種研究方法。研究者蒐集臺北市國民小學參與「中小學組織再造及人力規劃試辦方案」之相關文件資料,並自編「臺北市國民小學學校組織再造調查問卷」,受試者包括臺北市92至95學年度參與試辦方案之9所國民小學及未參與試辦方案之9所國民小學,普查該18所國民小學之1,000名教師,可用問卷回收率達70.6﹪。茲根據研究所得,做成結論如下。
壹、臺北市參與試辦方案之國民小學為提升學校效能等因素參與試辦後,由試辦小組進行宣導、規劃試辦與檢討,雖面臨配套措施尚未健全等困難,但以各種組織再造策略,期許達成預定目標。
貳、臺北市參與試辦方案之國民小學教師對於試辦成果普遍表示肯定滿意與支持,除達成教育部與臺北市政府教育局之四項預期目標外,並獲得學校成員、家長與學生之高度肯定。
參、臺北市國民小學教師對於國民中小學組織再造與人力規劃試辦方案認知情形屬中等程度。
肆、不同性別、年齡、服務年資、最高學歷、現任職務、學校規模、學校地區、學校校齡、參與方案與否之臺北市國民小學教師對試辦方案認知情形達顯著差異。
伍、臺北市國民小學教師對於國民中小學組織再造與人力規劃試辦方案支持度屬中上程度,且最支持「總量員額管制,彈性調整處室編制」。
陸、不同性別、服務年資、學歷、現任職務與學校地區的臺北市國民小學教師對國民中小學組織再造與人力規劃試辦方案支持度達顯著差異。
柒、臺北市國民小學教師對於組織再造試辦方案整體認知程度與支持度相關情形
達顯著。
捌、臺北市國民小學教師對於「學校整體滿意度」屬中上程度。
玖、不同職務、學校規模、學校地區、學校校齡、參與試辦方案與否之臺北市國民小學教師對學校現況滿意度達顯著差異。
拾、臺北市國民小學教師強烈贊同「部分行政工作可視性質改由『一般行政』或『教育行政』專長之職員擔任,如總務處主任與組長」;同時贊成「學校控留部分教師員額改聘兼任人員」,並相當支持「與教學無關之行政工作採勞務外包」等組織員額彈性規劃之作法。
拾壹、五成以上臺北市國民小學教師同意小幅度調整學校組織架構。
茲根據以上結論,提出教育行政機關與學校執行「國民中小學組織再造與人力規劃試辦方案」之建議如下。
壹、參與試辦方案學校實施成效良好,參與試辦學校數量值得逐年增加,教育部可考慮持續擴大試辦。
貳、安排訪視活動、舉辦成果發表會或成立校際策略聯盟,以瞭解學校試辦情形並分享交流經驗,以利檢討改進。
參、採取漸進式的學校組織再造,小幅度調整行政組織結構。
肆、調整不同學校規模之人員編制或擴大學校行政人員編制。
伍、妥適善用校內外人力資源並控留部分教師員額改聘兼任、代課、教學支援人員。
陸、非屬教學專業之固定項目委外辦理,由教育行政機關統一發包。
柒、依據學校特色與需求,彈性規劃整體組織再造及人力調整,並持續檢討改進。
捌、持續宣導與溝通組織再造與人力規劃試辦方案,並加強特定族群之宣傳,由下而上建立共識,擴大組織再造參與層面。
玖、教育行政機關在法令與經費上提供相關配套措施,增加學校的執行力與行動力。
拾、組織再造與人力規劃試辦方案的推動應由組織結構的調整邁向組織文化的
重塑。
拾壹、對未來研究的建議。 / “The Organization Restructuring and Human Resource Planning Project of the Elementary and Secondary School” policy is a complement to the implementation of Grade 1-9 Curriculum. It emphasizes school-based curriculum and hopes to expand the responsibility of teaching and administration, to alleviate the loads of teaching and administration, and to improves the costs-benefits of educational budgets through total personnel control and adjustment of elementary and secondary schools’ organization and human resource structure. The purposes of this study were to realize the implementation and effectiveness of the organization restructuring and human resource planning project of elementary and secondary schools in Taipei, to investigate the level of cognition and support of this project from the teachers of elementary schools in Taipei, and to understand their satisfaction levels toward school and their opinion regarding organization planning of schools. The research methods used in this study were document analysis and questionnaires. The researcher collected relevant documents regarding this project from elementary schools in Taipei and designed “The Organization Restructuring Questionnaire of Elementary Schools in Taipei”. The participants included 9 participating elementary schools and 9 non-participating elementary schools in Taipei from the academic year of 92 to 95. The questionnaires were sent to 1000 teachers from this 18 elementary schools. The valid rate of return is 70.6 %. The results of this study were as follows:
1.Due to the reasons of being appointed from the educational department, considering the needs of the schools, improving school effectiveness, and activizing school human resources, the elementary schools in Taipei which participating in this project first formed a committee to promote, plan, and evaluate.Although facing the difficulties of immature conceptualization and the void of corresponding interventions, five restructuring strategies including adjusting organization structure, re-designing job duties, re-allocating human resources, teaming the task forces ,and simplifying operation process were used. In addition to attain the four expected goals of the Ministry of Education, it was also hoped that certain goals regarding administration management, organization structure, teaching , learning, and parents’ service were be achieved.
2.The elementary teachers participating in this project expressed general satisfaction and support toward the results. Besides the four expected goals from The Ministry of Education and Taipei City Government Educational Department, highly recognition from the staff, parents and students were acquired.
3.The elementary school teachers in Taipei expressed medium cognition level toward this project.
4.There were significant differences in the cognition level toward this project between gender, age, seniority, education background, position, school scale, school area, and participation or not of the elementary school teachers in Taipei.
5.The elementary school teachers in Taipei expressed medium to high support level toward this project and support “total personnel control and flexibly adjust the organization of units” the most.
6.There were significant differences in the support level toward this project between different gender, seniority educational background, position, and school areas of the elementary school teachers in Taipei.
7.There was significant positive correlation between the cognition level and support level toward this project of the elementary school teachers in Taipei.
8.The elementary school teachers in Taipei expressed a medium to high satisfaction level toward “the general satisfaction of school”.
9.There were significant differences in the satisfaction level toward the present status of school between different position, school scale, school area, school history, and participation or not of the elementary school teachers in Taipei.
10.The elementary school teachers in Taipei strongly agreed that:
(1)Some of the administration work can be took by staffs with normal administration specialty or educational administration specialty ;
(2)School maintained certain personnel quatos and hire part-time employees .
(3)Outsourcing the non-teaching relevant administration work.
11.Half of the elementary school teachers in Taipei agreed small-scale school organization restructuring.
According to the above results, suggestions were provided to the administration institutions and schools which participated in the project:
1.The school participating in the project had good performance. Therefore, the Ministry of Education could consider expanding the participation to more schools gradually.
2.In order to share the experience and to benefit improvement, it is suggested to arrange visiting activities, to hold a results presentation, or to establish strategic alliances between schools.
3.Proceed school restructuring gradually and have small-scale administrative organization restructure.
4.Adjust the staffing of different school scales and expand the staffing of school administration personnel.
5.Using the human resources outside from the school more properly and maintain the teacher quotas to employ part-time, substitute teacher or teaching-supportive staff.
6.Outsourcing the non-teaching items through educational administration institutions.
7.According to the characteristics and demands of the schools, plan organization structure and human resources adjustment flexibly and evaluation continuously.
8.Promote and communicate the project continuously and reinforce the advertising to specific audience in order to expand the scope of organization restructuring.
9.In order to increase the execution of schools, educational administration institutions should provide corresponding interventions in laws and budgets.
10.The promotion of the organization restructuring and human resource planning project should move from the adjustment of organization structure to the re-shaping of organizational culture.
11.The recommendation to future research.
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L’idiotie du réel : de Clément Rosset à Hong SangsooAlbert, Christine 08 1900 (has links)
Nous nous intéresserons dans ce présent mémoire à l’« idiotie » du réel à partir de deux œuvres, celle du philosophe français Clément Rosset et celle du cinéaste sud-coréen, Hong Sangsoo. Nous poserons comme hypothèse que ces deux auteurs, à travers leurs théorie du réel, qu’elle soit philosophique ou esthétique, arrivent à un constat commun : le réel est « idiot », non pas au sens d’imbécile, mais en son sens premier c’est-à-dire « singulier, sans reflets ni doubles » (Rosset). Pour vérifier cette hypothèse nous procéderons d’abord par la construction d’un cadre théorique réalisé à partir de la définition rossetienne du réel. Ce cadre nous permettra de problématiser à la fois l’utilisation du zoom, la construction narrative, ainsi que les jeux temporels propres aux films de Hong, et ce, à partir de trois films du cinéaste : « Le pouvoir de la province de Kangwon » (1998), « Night and Day » (2007) et « Matins calmes à Séoul » (2011). Enfin il sera question, dans la dernière partie de ce mémoire, d’observer quelles peuvent être les conséquences engendrées par le fait de reconnaître ou non l’idiotie de toute réalité, à la fois dans des termes philosophiques mais également au plan de la prise d’images photographiques ou cinématographiques. / In this master’s thesis we will focus on the idiocy of reality in the work of two authors: Clément Rosset, a French philosopher, and Hong Sangsoo, a South-Korean filmmaker. As a hypothesis we will defend that both Rosset and Hong, through their theory of reality, come to the same conclusion: the reality is “idiot”, not in the sense of stupid, but in its primary meaning, in other words “singular, without any glare or double” (Rosset). To verify this assumption we will first build a theoretical framework based on Clément Rosset’s definition of the “réel”. This theoretical framework will allow us to problematize the use of the zoom, the narrative construction and the temporal games present in three Hong Sangsoo movies that we will analyze: “The Power of Kangwon Province” (1998), “Night and Day” (2007), “The Day He Arrived” (2011). Finally, in the last chapter we will discuss and observe what may be the consequences of recognizing or not the idiocy of any reality, in philosophical terms and for cinematographic creation.
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UCN Detector development for the TRIUMF Neutron EDM experimentFleurette, Doresty Fonseca 07 April 2016 (has links)
A new measurement of the neutron electric dipole moment (nEDM) is being
developed at TRIUMF, where a high density source of ultra cold neutrons
(UCN) is currently under construction. A fast, high-efficiency UCN detector
is needed for the experiment, and a 6-Li doped glass scintillation detector is
being explored for this purpose. In this work, simulations and test measurements
were carried out to optimize the light guide design for the new UCN
detector. Acrylic and air-core light guides, the latter with two different reflecting
surfaces, were considered. Three prototype light guides were constructed
and tested, and results were compared with simulations. The best solution
was found to be an acrylic guide, wrapped with mylar foil. For a guide 12
cm in length as required by the experimental layout, a lower limit of approximately
25 photoelectrons per neutron capture was established for the proposed
geometry and photomultiplier configuration. / May 2016
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1940年代戰爭動員體制下殖民地台灣與朝鮮文學中的地方書寫 / Local literature in Taiwan and Chosen, Japan’s colonies in 1940’s許育婷, Hsu, Yu Ting Unknown Date (has links)
本文探討1940年代地方文學書寫,藉由台灣與朝鮮對照呈現當時地方書寫產生的特殊背景:不同立場對地方書寫的期待、作家1940年代書寫時如何表現。藉上述的角度,試圖呈現殖民地地方書寫的意義。
殖民地文學中,捕捉在地特色、獨有風物的題材向來備受關注。1940年代更受日本帝國面臨發展困境,走向動員戰爭之路策略影響。使得文藝因應總力戰策動各層面投入戰爭,而背負增進帝國認同的任務。「新體制」與「大政翼贊會」的推行與成立,顯示當時精神統制擴大、也反映東亞協同、對抗西方文明的框架,將殖民地作為帝國外緣/前線的策略。地方特色的突顯與應用即受到這些政策與思維籠罩。
此時,殖民地文藝創作環境面對權力集中一元化,不僅創作語言受限、言論出版高壓管制;官方更積極介入文藝團體、舉辦獎項,加強國策宣傳。文藝創作空間、資源侷限下,新體制與大政翼贊會為殖民地文化界帶來發揮的機會。在地方書寫蘊含國民認同基礎、傳統根源等元素,既呼應政策對於國民文化,殖民地文化人亦可爭取活動機會。這一類書寫,最初以地方色、鄉土色展現地方特殊性的書寫為普遍認同,後隨戰爭國策要求提高,強調服膺日本精神、支援戰爭的內容。
殖民地這一波的地方書寫當中,題材、作品氛圍、敘事型態皆與以往略有不同。題材上,應和國策創作增加、探索傳統價值與批判西方、塑造道德模範反省文化的進程。作品氛圍與敘事型態上,揮去不見希望的氛圍,轉為明朗、健康、動人,更以人物或藉由回歸自然、致力生產、甚至參與戰爭找到生命的意義與希望。
本文即選取兩組作家作品為代表。呂赫若、俞鎮午運用風俗習慣、傳統禮節,表現殖民地特殊風貌,並以倫理、全體性角度肯定傳統價值。張文環、金史良以鄉土為基底,在堅毅樸實的生活中獲得力量。他們在地方書寫框架中,迴避國策密切相關的題材,書寫熟悉事物表現地方特殊性,運用風俗習慣、神話傳說、禮儀、信仰等表現殖民地的人文風景,並一改先前啟蒙的批判角度。這些書寫策略具有保存殖民地文化甚而是民族精神的可能,卻也在時空限制下與戰爭動員的政策意識有所呼應。在兩地的同中有異的書寫成果裡,也見證地方書寫的政治策略、多種意涵,在殖民地的空間裡延伸出更多迂迴與曖昧。 / This article tries to analyze local literature in Taiwan and Chosen, Japan’s colonies in 1940’s.
First of all, by analyzing the form of mobilization under the Total War System in 1940, it shows the influence on Japan’s military operation and manipulation. On one hand, the authority made use of centralized management on politics; on the other hand, ideas such as Overcoming Modernity and East Asia Alliance Leader were offered to let people acknowledge the war and sacrifice for it. Through these concepts, the authority reached to the notion which based on the native for people to possess.
Secondly, after the foundation of Konoe shintaisei(新體制) and Taisei Yokusankai(大政翼贊會), literature was asked to proclaim the war more strategically. At that time, under the limitation of the amount of paper, local literature in colonies was requested to write in Japanese and scrutinized by the government. In addition, the authority even established literature and art organizations and set up literary prizes to advertise the war. In this way, local literature not only answered the policy but also gave the chance of displaying colonial features to those authors. In the beginning, both the authority and most of the writers accepted the method of using local color to exhibit the colony, however, this method was applied to announce the Japanese spirit and support the war little by little.
Under this circumstance, colonies changed the way of literary expression. There were more subjects which conformed the national policy, explored the value of tradition, and criticized the Western to reflect the advancement of culture and then create moral standards. It was the atmosphere of the literature that turned to be bright and cheerful. Moreover, narrative patterns were performed on the characters, such as returning to nature, devoting to production, finding meanings and hopes by participating in the war.
This article represents local literature in colonies in 1940 by taking examples of two groups of writers. One of the groups ,which is represented by Lü He-ruo (呂赫若) and You Jin-Oh (유진오), utilized traditional customs and manners as distinguishing features in colony. Furthermore, from the viewpoint of ethic and totalitarianism, they tried to approve the value of tradition. Yet, on the other hand, Chang wen-Huan(張文環) and Kim Saryan(김사량) gained power from difficulty and arduousness in life through the background of rural places. Both of them avoided responding to the national policy in this kind of writing pattern.
As previously stated, these writers portrayed what they were familiar with to show the feature in local places. Ranging from customs, practices, folklore, manners to religions were what the writers employed to illustrate the cultural characteristics in colonies. Besides, the viewpoint changed from the criticism of enlightenment. These kinds of writing devices with the hope of preserving local culture and even national integrity. However, it was the restriction on politics and the times made literary works echo with the authority’s ideology at the same time.
In the view of Compare Taiwan with Chosen, difference in literary works were testified to show the various meanings from colonial strategies in politics and writers characters in the meantime.
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Testing the seams of the American dream : minority literature and film in the early Cold WarBurns, Patricia Mary 26 September 2011 (has links)
Testing the Seams of the American Dream: Minority Literature and Film in the Early Cold War delineates the concept of the liberal tolerance agenda in early Cold War. The liberal tolerance message of the U.S. government, the Democratic Party, and others endorsed racial tolerance and envisioned the possibility of a future free from racism and inequality. Filmmakers in often disseminated a liberal message similar to that of the politicians in the form of “race problem” films. My shows how these films and the liberal tolerance agenda as a whole promises racial equality to the racial minority in exchange for hard work, patriotism, education, and a belief in the majority culture. My first chapter, “Washing White the Racial Subject: Hollywood’s First Black Problem Film,” performs a close reading of Arthur Laurents 1946 play Home of the Brave, which features a Jewish American protagonist, in conjunction with a reading of the 1949 film version, which has an African American protagonist. The differences between the two texts reveal the slippages in the liberal tolerance agenda and signal the inability of filmmakers to envision racial equality on the big screen. “The American Institution and the Racial Subject,” my second chapter, discusses the 1949 film Pinky as well as Américo Paredes’s George Washington Gómez and Monica Sone’s Nisei Daughter. All of these works suggests that the attainment of education promises entry into the mainstream by racial minorities, yet Paredes and Sone question this process by interpreting it as resulting in the dual segregation of their protagonists. My third chapter, “Earning and Cultural Capital: The Work that Determines Place,” looks at the promise that with hard work anyone can attain the American Dream. I show how the 1951 film Go for Broke!, Ann Petry’s The Street, and José Antonio Villarreal’s Pocho work to dispel this American myth. My final chapter, “The Regrets of Dissent: Blacklists and the Race Question,” examines the 1954 film Salt of the Earth alongside Chester Himes’s If He Hollers Let Him Go and John Okada’s No-No Boy to reveal the dangerous mixture of race and dissent in this era. / text
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Evolution and decay of peneplains in the northern Lhasa terrane, Tibetan Plateau / Revealed by low-temperature thermochronology, U-Pb geochronology, provenance analyses, and geomorphometryHaider, Viktoria L. 01 July 2014 (has links)
Diese Dissertation befasst sich mit der Entwicklung von “Fastebenen”, die im Weiteren einheitlich als “Peneplains” bezeichnet werden, sowie dem Zerfall dieses markanten geomorphologischen Erscheinungsbildes im südlichsten Teil des tibetischen Plateau dem sogenannten Lhasa Block.
Im Zuge dieser Arbeit konnten neue Erkenntnisse über die Hebungsgeschichte und der Sedimentverteilung in diesem Untersuchungsgebiet gewonnen werden. Diese Ergebnisse tragen zu einem besseren Verständnis der geodynamischen Entwicklung Asiens bei, die bis heute viele Fragen aufwirft.
Ende des 19. Jahrhunderts wurden Peneplains als metastabile geomorphologische Formen angesehen, die im Zuge großflächiger Erosion entstehen. Die Bezeichnung Peneplain und das dahinter stehende Konzept werden seitdem von der geomorphologischen Gemeinschaft jedoch kontrovers diskutiert. Bis heute gibt es keine standardisierte bzw. repräsentative Definition für das nicht zu übersehende landschaftsbildende Phänomen der Peneplains. Dementsprechend gibt es auch nur wenige Ansätze zu Modellierungen oder Berechnungen mit Geoinformationssystemen. Hier, in dieser Dissertation, werden idealisierte Peneplains als erhöhte, gleichmäßige und großflächige Ebenen mit abfallenden Hängen verstanden, auch wenn sich landschaftsbildende Peneplains oft gekippt darstellen und durch tektonische Prozesse gestört bzw. bereits durch fortschreitende Erosionsprozesse angegriffen sind.
Gut erhaltene Peneplains sind speziell für das Gebiet um den höchstgelegenen See der Welt, dem Nam Co, im nördlichen Teil des Lhasa Blocks im Hochland von Tibet charakteristisch. Die Peneplains zerschneiden das dort vorkommende viel ältere und vorwiegend granitische Gestein sowie die angrenzenden Metasedimente.
Zur Bestimmung der Abkühl- und Hebungsalter der Granite wurden geo- und thermochronologische Methoden wie Zirkon U-Pb, Zirkon (U-Th)/He, Apatit (U-Th)/He und Apatit-SpaltspurenDatierung angewendet. Neben der Hebungsrate konnte auch die Freilegung des granitischen Gesteines ermittelt werden. Mit der Methode zur Bestimmung des U-Pb-Zirkonalters konnten zwei Intrusionsgruppen, um 118 Ma und 85 Ma, festgestellt werden. Ebenso wurden vulkanische Aktivitäten nachgewiesen und auf einen Zeitraum zwischen 63 Ma und 58 Ma datiert.
Thermische Modelle, aufbauend auf Zirkon- und Apatit-(U-Th)/He-Datierungen sowie auf ApatitSpaltspuren-Daten der untersuchten Granitoide, ergeben einen Hebungs- und Abkühlungszeitraum von 75 Ma bis 55 Ma mit einer Hebungsrate von 300 m/Ma, welche im Zeitfenster zwischen 55 Ma und 45 Ma stark abfällt auf 10 m/Ma. Die Auswertung der Messdaten unserer Kooperationspartner an der Universität Münster zu kosmogenen Nukliden zeigen sehr niedrigen Erosionsraten von 6-11 m/Ma und 11-16 m/Ma, in den letzten 10.000 Jahren die in den einzelnen Einzugsgebieten ermittelt wurden. Diese Daten zeugen von einer noch immer andauernden Periode der Stabilität und tragen zur Erhaltung der Peneplains bei.
Während der anhaltenden Phase der Erosion und Einebnung sind vor ungefähr 45 Ma in der untersuchten Region zwischen 3 km und 6 km Gestein abgetragen und weg transportiert worden.
Es ist naheliegend, dass das abgetragene Material als Sediment über das vorhandene Flusssystem fast vollständig in die heute bestehenden Ozenane transportiert wurde. Im Lhasa Block können nur verhältnismäßig wenig Sedimente aus dieser Zeit nachgewiesen werden. Alle bisherigen Untersuchungsergebnisse sowie die durchgeführte Sediment-Herkunftsanalyse untermauern die Theorie, dass die Peneplainbildung und ihre Erosionsprozesse in niedriger Höhe - höchstwahrscheinlich auf Meeresniveau - stattgefunden haben muss. Dieser Prozess wurde durch die Kollision des indischen Kontinents mit Asien gestoppt. Die resultierende Krustenverdickung führte zu einer Hebung der Landschaft mit den Peneplains, von Meeresniveau auf 5.000 bis 7.000 Höhenmeter. Die auf dem “das Dach der Welt” vorherrschenden idealen Klimabedingungen haben anschließend für die fast vollständige Erhaltung der Peneplains gesorgt.
Der zweite Teil der Dissertation befasst sich mit der Entwicklung einer robusten Methode Peneplains anhand digitale Höhenmodelle (DEM) zu berechnen bzw. zu kartieren. Frei zugängliche DEMs machen es möglich, Erdoberflächen repräsentativ mathematisch und statistisch zu analysieren und zu charakterisieren. Diese Analysemethode stellt eine ausgezeichnete Möglichkeit dar, die Peneplains mittels aussagekräftiger Algorithmen zu charakterisieren und digital zu kartieren.
Um Peneplains algorithmisch von der Umgebung klar abgrenzen zu können, wurde ein komplett neuer Ansatz der Fuzzylogik angewandt. Als DEM-Basis wurde ein 90 arcsec-DEM der Shuttle Radar Topography Mission (SRTM) verwendet. Mithilfe eines Geoinformationssystems (GIS) wurden Algorithmen geschrieben, die vier verschiedene kritische Parameter zur Beschreibung von Peneplains berücksichtigen: (I) Gefälle, (II) Kurvigkeit, (III) Geländerauhigkeit und (IV) Relative Höhe. Um die Eignung der Methode zu prüfen, wurde auf Basis der SRTM-DEM weltweit kartiert und mit schon in der Literatur beschriebenen Peneplains verglichen. Die dabei erhaltenen Ergebnisse von den Appalachen, den Anden, dem Zentralmassif und Neuseeland bestätigen dass ein Einsatz des Modells, weltweit und unabhängig von der Höhenlage möglich ist.
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L’idiotie du réel : de Clément Rosset à Hong SangsooAlbert, Christine 08 1900 (has links)
Nous nous intéresserons dans ce présent mémoire à l’« idiotie » du réel à partir de deux œuvres, celle du philosophe français Clément Rosset et celle du cinéaste sud-coréen, Hong Sangsoo. Nous poserons comme hypothèse que ces deux auteurs, à travers leurs théorie du réel, qu’elle soit philosophique ou esthétique, arrivent à un constat commun : le réel est « idiot », non pas au sens d’imbécile, mais en son sens premier c’est-à-dire « singulier, sans reflets ni doubles » (Rosset). Pour vérifier cette hypothèse nous procéderons d’abord par la construction d’un cadre théorique réalisé à partir de la définition rossetienne du réel. Ce cadre nous permettra de problématiser à la fois l’utilisation du zoom, la construction narrative, ainsi que les jeux temporels propres aux films de Hong, et ce, à partir de trois films du cinéaste : « Le pouvoir de la province de Kangwon » (1998), « Night and Day » (2007) et « Matins calmes à Séoul » (2011). Enfin il sera question, dans la dernière partie de ce mémoire, d’observer quelles peuvent être les conséquences engendrées par le fait de reconnaître ou non l’idiotie de toute réalité, à la fois dans des termes philosophiques mais également au plan de la prise d’images photographiques ou cinématographiques. / In this master’s thesis we will focus on the idiocy of reality in the work of two authors: Clément Rosset, a French philosopher, and Hong Sangsoo, a South-Korean filmmaker. As a hypothesis we will defend that both Rosset and Hong, through their theory of reality, come to the same conclusion: the reality is “idiot”, not in the sense of stupid, but in its primary meaning, in other words “singular, without any glare or double” (Rosset). To verify this assumption we will first build a theoretical framework based on Clément Rosset’s definition of the “réel”. This theoretical framework will allow us to problematize the use of the zoom, the narrative construction and the temporal games present in three Hong Sangsoo movies that we will analyze: “The Power of Kangwon Province” (1998), “Night and Day” (2007), “The Day He Arrived” (2011). Finally, in the last chapter we will discuss and observe what may be the consequences of recognizing or not the idiocy of any reality, in philosophical terms and for cinematographic creation.
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Modélisation de la formation des décohésions dues à l’hydrogène dans l’acier 18MND5 / Modelling of high pressure hydrogen induced internal cracks in an 18MND5 low alloy steelSezgin, Jean-Gabriel 24 February 2017 (has links)
Les viroles en acier microallié 18MND5, destinées aux générateurs de vapeur, présentent une composition hétérogène à plusieurs échelles. Un écart au procédé de fabrication ou une teneur en hydrogène excessive, peuvent conduire à la formation des Décohésions Dues à l’Hydrogène. Ces DDH résultent de la désorption de l’hydrogène interne lors du refroidissement jusqu’à température ambiante. La pression interne n’étant pas mesurables expérimentalement, une modélisation du phénomène est requise. Afin de préciser les mécanismes sous-jacents, il est proposé un scénario de formation de ces défauts s’appuyant conjointement sur une expertise et la modélisation des processus de diffusion-désorption-propagation. Les observations ont révélé une corrélation entre les DDH, les zones ségrégées et les amas de MnS (sites préférentiels d’initiation). Un modèle de diffusion dans un milieu hétérogène a été proposé afin d’évaluer la pression interne associée. La pression maximale excède ainsi 8600 bar en considérant une loi d’Abel-Noble optimisée du gaz réel. Le couplage de ce modèle avec la mécanique de la rupture a permis de quantifier l’évolution des paramètres relatifs à la propagation (pression interne, taille finale, vitesse, …). Un scénario de formation des DDH industriel a ainsi pu être formulé sur la base d’une étude paramétrique. Bien que les simulations préliminaires corroborent le retour d’expérience, le modèle raffiné et la prise en compte du gonflement de la DDH semblent sous-estimer la cinétique. Le caractère multi-fissuré des amas de MnS (homogénéisation des propriétés mécaniques) associé à un critère de rupture à l’échelle locale permettrait d’ajuster ce modèle. / Heat generators are manufactured from ingots of 18MND5 (A508cl3) low alloy steel and present composition heterogeneities at different scales. Under specific conditions (non-respect of guidelines or high initial content of H), Hydrogen Induced Cracks (HIC) may result from diffusion-desorption of internal hydrogen during cooling down to room temperature. Since neither hydrogen redistribution nor its internal pressure within cavities could be measured by experimental techniques, quantitative investigation is based on the modelling of related physical phenomena. A scenario of HIC formation, based on industrial feedback and modelling, has been proposed. A correlation between these defects, segregated areas and clusters of MnS (preferred initiation sites) has been revealed by expertise of HIC. A model of diffusion in heterogeneous alloys has then been proposed to assess the maximal pressure of H2 in such HIC. Simulation has shown that internal pressures above 860MPa are reached by considering an optimized Abel-Noble real gas behavior. The previous model has then been coupled to a failure mechanics procedure to characterize and quantify the crack growth parameters. Based on a parametric study, a scenario of HIC formation during the cooling has been proposed regarding process. Although results from preliminary simulations matched with feedback, the refined model based on the pressure induced elastic deformation of HIC has been developed but provided an underestimated kinetic of crack growth. Consequently, the multi-cracked nature of MnS clusters (homogenization of mechanical properties) and the updated local failure criterion appear to be a viable path to adjust predictions.
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Vibrational relaxation and dephasing of Rb2 attached to helium nanodropletsGrüner, Barbara, Schlesinger, Martin, Heister, Philipp, Strunz, Walter T., Stienkemeier, Frank, Mudrich, Marcel January 2011 (has links)
The vibrational wave-packet dynamics of diatomic rubidium molecules (Rb2) in triplet states formed on the surface of superfluid helium nanodroplets is investigated both experimentally and theoretically. Detailed comparison of experimental femtosecond pump–probe spectra with dissipative quantum dynamics simulations reveals that vibrational relaxation is the main source of dephasing. The rate constant for vibrational relaxation in the first excited triplet state 13Σ+g is found to be constant γ ≈ 0.5 ns−1 for the lowest vibrational levels v [less, similar] 15 and to increase sharply when exciting to higher energies. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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