Global ETD Search

21	Two dimensional two fluid model for sodium boiling in LMBFR fuel assemblies GRANZIERA, MARIO R. 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:26:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:22Z (GMT). No. of bitstreams: 1 00951.pdf: 4937591 bytes, checksum: 160731d29ec9edf1fc78d0034f24638b (MD5) / Thesis (Doctorate) / IPEN/T / Massachusetts Institute of Technology - Cambridge, Mass - MIT analog systems reactor simulators breeder reactors fast reactors liquid metal coolant metal cooled reactors sodium cooled reactors IEA-ZPR-reactor
22	Two dimensional two fluid model for sodium boiling in LMBFR fuel assemblies GRANZIERA, MARIO R. 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:26:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:22Z (GMT). No. of bitstreams: 1 00951.pdf: 4937591 bytes, checksum: 160731d29ec9edf1fc78d0034f24638b (MD5) / Thesis (Doctorate) / IPEN/T / Massachusetts Institute of Technology - Cambridge, Mass - MIT analog systems reactor simulators breeder reactors fast reactors liquid metals metal cooled reactors sodium cooled reactors iea-zpr reactor
23	The Green Charge : Advanced Battery Technologies for a Sustainable Future Morantes, Gabrielle January 2024 (has links) In order to combat the greenhouse gas emissions from the transportation sector, battery-powered electric vehicles have risen as an alternative that offers a cleaner and more sustainable mode of transportation that reduces reliance on fossil fuels and decreases carbon footprints. The climate scenario goals set by the International Energy Agency - the Net Zero Emissions, Announced Pledges, and Stated Policies Scenarios - revolve around an increased and expeditious demand for electric vehicles, machines that are intrinsically intertwined with battery production. This study focused on the sustainability of the battery's positive electrode (cathode), a critical, material-intensive component. The three different types of cathodes – Layered, Spinel, and Polyanionic – were studied to determine the basics behind their performances. It then became evident that the key ingredients of a battery cathode are lithium, manganese, nickel, iron, and aluminium. These materials were quantified in terms of their production, reserves, and resource numbers. An analysis on the electric vehicle market as a function of the type of battery chemistries was performed to determine how much the best sold and produced EV models consumed in terms of the different materials and how material intensive they were. The future production demand of the ingredients was studied. For lithium, this involved running two polynomial regressions with a demand and production peak in 2050. For manganese and nickel, the compositions of a hypothetical cathode were iterated to match the climate scenario targets, and thus, determine which compositions would meet them. Throughout the investigation, several aspects were uncovered: the current dominant battery chemistry in the EV market is the iron-rich, polyanionic type. However, to compensate for the lower performance of LFP batteries, manufacturers increased cathode size, nullifying the lithium savings. Regarding lithium production, a polynomial growth with a linear decline post the 2050 peak would seamlessly meet the climate scenario goals without exhausting the planetary resources. Manganese proved more sustainable than nickel, although nickel-rich cathodes remain the preferred choice. Manganese-rich cathodes showed the best material efficiency. Significant challenges remain in achieving sustainable EV batteries. The supply chain is highly centralized, and there are limited alternatives to lithium-reliant chemistries. Bereft from economically feasible lithium production methods, the industry is struggling to diversify its technology whilst treading lightly on fragile supply chains. There is comfort in the fact that the availability of these materials is still profuse - but this prosperity may not last if the projected demand is not congruent with the current state of nickel reserves, and if policy and car manufacturers continue to ignore the inherent chemical and physical limitations of the cathode types they prefer. In conclusion, while progress has been made, ensuring the sustainability of EV batteries requires continued innovation and strategic resource management. batteries electric vehicles IEA climate targets material availability positive electrode materials Sustainable Development Earth and Related Environmental Sciences Geovetenskap och miljövetenskap
24	中共當前的能源戰略及其對外交的影響王道和 Unknown Date (has links) 本研究先以世界能源的發展歷程為座標，再將中國大陸的能源發展歷程放進這個框架，藉以解釋其演變的情形，並歸納中共當前的能源戰略，且進一步探討其對外交的影響。首先，使用文獻分析法敘述人類利用能源資源的歷史，藉以瞭解世界能源的替代過程。其次，回顧近代以來，以石油為主的世界能源發展歷程，也就是從石油三巨頭主導的墨西哥灣時代、石油七姊妹壟斷的波斯灣時代、石油輸出國組織（OPEC）與國際能源總署（IEA）對抗的時代，以及現今的三大油氣供需區的形成，從中總結出能源發展與國際政治之間的歷史經驗。最後，就石油、天然氣、煤炭及鈾礦等當前世界主要的能源，介紹其分佈的情況及特徵，以及世界主要國家因此相應而生的能源戰略。其次，以世界能源的發展歷程為背景，觀察中共自1949年建立政權以來，毛澤東、鄧小平、江澤民及胡錦濤等四代領導人，在各自面對不同的國內外能源形勢時，其能源發展政策所具有的戰略內涵為何。並且進一步比較各時期的能源發展政策，藉以瞭解造成中共能源戰略轉變的主要因素。接著透過對近幾年相關能源文獻的分析，歸納出中共當前能源戰略的面貌。並依戰略的形式，分析中共能源戰略的目標，及其達成目標的方法。最後，以目前中共對國外能源的需求來源做為觀察的脈絡。將中共的國際能源外交版圖，放進由主要國家所構築的國際政治版圖中，以探討中共的能源戰略對其外交工作所產生的影響，並就中共能源外交戰略的趨向進行分析並提出看法。能源戰略能源外交能源發展戰略能源安全戰略 IEA OPEC
25	PISA i skolan : hur lärare, rektorer och skolchefer förhåller sig till internationella kunskapsmätningar / PISA in Schools : how teachers, head teachers and municipal school directors relate to international assessments Arnesson, Daniel January 2016 (has links) This thesis addresses the local reception and use in Sweden of the major international large scale assessments (ILSAs) of student performance: Programme for International Student Assessment (PISA), Trends in International Mathematics and Science Study (TIMSS), Progress in International Reading Literacy Study (PIRLS) and International Civic and Citizenship Education Study (ICCS). The aim is to describe and analyze how Swedish teachers, principals and school directors interpret and possibly use ILSAs in their professional practice. ILSA is treated here as a new idea or a new social technology defining what constitutes good (or bad) education. The theoretical framework combines a top-down perspective provided by Rogers’ (2003) Diffusion of Innovation theory, and a complementary, more critical Policy Enactment approach (Ball et al. 2012), stressing the import-ance of context and local actors’ perspectives. Empirically, the thesis is based on 40 semi-structured interviews carried out in the 2011-2012 school year with teachers, principals and municipal school directors in five municipalities and 12 compulsory schools, selected to cover diverse municipalities, schools, and respondents. The respondents perceive ILSAs as valid evaluations of the Swedish school system. Most think it is important to compare results of different nations, although ILSA is not expected to cover the whole curriculum. Most interviewees are aware that Swedish ILSA results have been declining for years and perceive an urgent need to reverse this trend. However, few of the directors, principals or teachers believe that Swedish schools are in a deep crisis, as described in Swedish media. The participants frequently regard schools as primary determinants of ILSA results, and few blame family, socio-economic, cultural and contextual factors for the Swedish decline in ILSA rankings. There are significant differences between the three occupational groups in their reception and use of ILSA. Municipal school directors who are very well-informed emphasize the influence of ILSA on their local development efforts. Principals and teachers say that ILSAs have had modest direct effects on their work, but they argue that poor Swedish results in international assessments have had indirect effects, for instance by prompting the introduction of a new national curriculum. / <p>Contains an English summary.</p> compulsory education PISA TIMSS PIRLS ICCS OECD IEA municipal school directors principals teachers local reception diffusion of innovations policy enactment grundskola internationella kunskapsmätningar (IK) PISA TIMSS PIRLS ICCS OECD IEA kommunala skolchefer rektorer lärare lokalt mottagande Rogers diffusionsteori policy enactment
26	Vad har hänt med pojkars läsning? : En sammanställning av svenska pojkars resultat i internationella läsförståelseundersökningar / What has happened to Swedish boys' reading? : A compilation of Swedish boys’ results in international studies of reading competence Petersson, Isak January 2014 (has links) Denna studie ämnar sammanställa resultat från de internationella jämförelser av elevers läsförståelsekunskaper som Sverige deltagit i, med särskilt fokus på svenska pojkars prestationer i dessa undersökningar. Studiens syfte är att undersöka vilka trender som går att skönja i pojkars läsning, och analysera hur skillnader mellan svenska pojkar och flickors läsning ter sig över tid. En överblick ges dessutom av svenska pojkar och flickors samlade resultat i läsförståelsestudier. Totalt har material från tio internationella studier insamlats och analyserats. Data har hämtats främst från de Skolverket-rapporter som författats efter varje undersökning. I resultatanalysen påvisas bland annat att svenska pojkar såväl som flickor försämrat sina läsförmågor signifikant sedan första undersökningen 1970. Dessutom har könsskillnaden vuxit och i den senaste undersökningen, 2012, registrerade svenska elever rekordhöga könsskillnader i läsförmåga, en skillnad som till stor del kan attribueras till pojkars kraftigt försämrade läsförmågor. Vidare så framkom det i analysen att svenska pojkars såväl som flickors läsattityder har försämrats det senaste decenniet. Denna trend var emellertid tydligast bland pojkar. / This study aims to compile results from international surveys of students’ reading competence that Sweden has participated in, with particular focus on the results of Swedish boys. The purpose of the study is to reveal trends in boys’ reading, and analyse how differences between Swedish boys and girls’ reading has developed over time. The paper also offers an overview of Swedish boys and girls’ general performances throughout all surveys. In total, material from ten major international surveys has been analysed. Foremost, data has been collected from the survey reports written by the Swedish National Agency for Education. In analysing the material it was found, among other things, that Swedish boys as well as girls significantly have worsened their reading competence since the first survey in 1970. Furthermore, the gender differences in reading have increased considerably, and in the latest survey, PISA 2012, Swedish students registered historically high gender differences, a circumstance that largely could be attributed to the deteriorating results of Swedish boys. In addition, it became apparent that Swedish students’ reading attitudes have worsened the last decade, a trend particularly salient among boys. reading reading competence boys’ reading the gender gap boys’ underachievement PISA PIRLS OECD IEA reading attitudes gender differences in reading PISA 2012 läsning läsande läsförståelse läsförmåga pojkars läsning pojkars underprestation OECD IEA PISA PIRLS PISA 2012 läsattityder könsskillnader i läsförmåga Specific Languages Studier av enskilda språk
27	Energy, Environment and Transportation : An Actor-Role Network Analysis of the World Energy Outlook 1977-2016 Söderqvist, Felicia January 2019 (has links) This thesis explores how energy and environmental issues have been presented in the transportation sector over time in World Energy Outlook (WEO) publications; the flagship publication of the International Energy Agency (IEA). The thesis covers WEO publications from the first publication of 1977 up to 2016 (with the exception of WEO 1982). The data was extracted through the aid of interpretive content analysis, focusing on the transport sector. Energy and Environmental issues within the context of transportation were then discussed as to their roles and forms of action they were ascribed throughout the publications. Actor-network theory was used as a theoretical framework to map and showcase how these roles and actions conditioned and connected to each other. The results of the study show that energy has had a tendency to be divided into the camps of fuels that are either solutions or problems. The exceptions are biofuels, which stand out as fuels that are both solutions and problematic. The environmental issues are solved and caused through energy use, and in 1977,environmental consideration were presented as obstacles to energy security. In 1993 global warming and emissions have changed into being major policy concern. Pollution, congestion, dust, noise, and related health issues are added to the fray as time proceeds, and so are more forms of energy for solutions. Goals and interests showcased in the publications are shown to conflict with others, while energy efficiency as a solution has emerged as a solution to both global warming and energy security. The transport sector starts of as framed more asan area or space where environmental issues take place and solutions are implemented,however, increasing motorisation of the sector and traffic and its role as amajor emitter are later added as active aspects of the conditioning of thesector and in offsetting the solutions. Regional cases are used to exemplify the issues and solutions, with a major focus on OECD contexts, and technological renewal emerges early on as a mayor pathway in solving the environmental issues, through the support of consumers. However, the major issues still remain the same as in 1993. Energy Security Environment Transport Sector Energy Policy Actor-Network Theory Interpretive Content Analysis Role Actors International Energy Agency (IEA) World Energy Outlook (WEO) Environmental Sciences Miljövetenskap
28	The Impact of IEA Reports on Oil-Related Markets 陳俊源, Chen, Jiun-Yuan Unknown Date (has links) 國際能源機構(IEA)每個月的石油報告已經變成預測世界石油供給與需求一個很重要的資源。因此，我們蒐集從1990年10月到2005年12月中國際能源機構所發佈的179次宣告，利用事件研究法來衡量國際能源機構對石油相關市場的影響性。實證結果顯示，國際能源機構的石油報告的確對石油相關市場傳達重要的資訊；而國際能源機構報告的影響效果似乎會隨著國家的不同而有所不同；在當中，石油的生產和消費量多寡、石油的密集度和油價中稅占的比例都扮演重要的角色；此外，在國際能源機構的報告中，關於預測石油需求變化這方面似乎特別被大家所重視。 / This study examines the impact of International Energy Agency's Oil Market Reports on oil-related prices. The IEA reports, published monthly in Paris, have become the primary source of world oil supply and demand forecasts. We collect 179 announcements that released by IEA over the period October 1990 to December 2005. We analyze the effects of these reports on three oil-related markets, IPE Brent Crude futures, oil industry indices and stock prices of oil companies in six countries. Moreover, we separate the effects of IEA’s forecast changes on oil supply from non-OPEC countries and oil demand from North America and China in IEA’s report. The results confirm that IEA’s reports carry important information source for oil-related markets because more than one half of our sample companies have abnormal returns around the announcement date of IEA’s reports, and we explore these prices respond negatively to the release of IEA’s reports. We also find that the actively traded IPE Brent Crude futures contracts are affected by IEA’s reports, particularly for the change of demand in North America. Forecast changes in IEA’s reports regarding supply in non-OPEC countries, demand in North America and China show that most countries are affected by the changes in these reports. The evidences also show that British and Norwegian oil stock markets react more strongly to the change of oil demand in North America and China. Moreover, we find that participants in the oil market put more emphasis on demand changes reported by IEA, especially for China demand. And we provides empirical evidence that these companies are concerned more about the related releases of decreased demand in North America and increased demand in China. Finally, cross-sectional analysis of cumulative abnormal returns suggests that the reaction of American and Norwegian companies to IEA’s announcements is stronger than other countries, and the change of demand in North America and China and the size variable for individual company contribute to the changes of abnormal returns around IEA’s reports. 石油國際能源機構石油供給與需求事件研究法 oil IEA oil supply and demand event study Oil Market Report Non-OPEC Brent Crude
29	Mathematics and Mathematics Education Development in Finland: the impact of curriculum changes on IEA, IMO and PISA results Malaty, George 07 May 2012 (has links) (PDF) Mathematics has got roots in Finland in the last quarter of the 19th century and came to flourish in the first quarter of the next century. In the first quarter of the 20th century, mathematicians were involved in teaching mathematics at schools and writing school textbooks. This involvement decreased and came to an end by the launching of the ‘New Math’ project. Mathematics education for elite was of positive affect to higher education, and this has changed by the spread of education, the decrease of mathematics teaching hours at schools and the changes in school mathematical curricula. The impact of curriculum changes is evident in Finnish students’ performance in the IEA comparative studies, PISA and IMO. Mittag-Leffler Hjalmar Mellin Ernst Leonard Lindelöf Rolf Herman Nevanlinna Lars Valerian Ahlfors Ernst Bonsdorff Kalle Väisälä Elite Lehrplanänderungen Unterrichtsstunden Bildungsreformen Mathematikolympiaden Vergleichsstudien IEA TIMSS PISA PISA Formeln Algorithmen Unlogisches Problemlösen Alltagsmathematik Mittag-Leffler Hjalmar Mellin Ernst Leonard Lindelöf Rolf Herman Nevanlinna Lars Valerian Ahlfors Ernst Bonsdorff Kalle Väisälä elite curriculum changes teaching hours reforms Olympiads comparative studies IEA TIMSS PISA PISA formulas algorithms illogic problem-solving everyday life mathematics ddc:510 rvk:SD 2009
30	Mathematics and Mathematics Education Development in Finland: the impact of curriculum changes on IEA, IMO and PISA results Malaty, George 07 May 2012 (has links) Mathematics has got roots in Finland in the last quarter of the 19th century and came to flourish in the first quarter of the next century. In the first quarter of the 20th century, mathematicians were involved in teaching mathematics at schools and writing school textbooks. This involvement decreased and came to an end by the launching of the ‘New Math’ project. Mathematics education for elite was of positive affect to higher education, and this has changed by the spread of education, the decrease of mathematics teaching hours at schools and the changes in school mathematical curricula. The impact of curriculum changes is evident in Finnish students’ performance in the IEA comparative studies, PISA and IMO. info:eu-repo/classification/ddc/510 ddc:510

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