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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Persistent anomalies of the extratropical Northern Hemisphere wintertime circulation

Dole, Randall M January 1982 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Meteorology and Physical Oceanography, 1982. / Microfiche copy available in Archives and Science. / Vita. / Bibliography: leaves 218-225. / by Randall M. Dole. / Ph.D.
112

Setting the seeds for a green growth -A Study of biofuel development in Indonesia’s transport sector

Aaman, Sophia, Hessel Lundberg, Johan Henrik January 2017 (has links)
Climate change poses as one of the major environmental issues on a global scale today, with one of the largest contributor to the climate change being the greenhouse gas (GHG) emissions. GHG emissions in turn is known to a large extent originate in anthropogenic energy use, especially fossil fuel usage. This leads to almost a quarter of the global emissions today being emitted from the transport sector as the sector is primary fueled by fossil fuels. Biofuels have been promoted as a strong candidate for fossil fuel substitution as it has similar properties while being renewable. However, even as biofuels have been increasing annually since 2008 globally, there are still concerns associated with the usages that have hindered its replacement of fossil fuels. Indonesia, one of the most populated countries in Southeast Asia, is projected to be one of the world’s leading economies in 2050. In 2030, Indonesia in projected to have doubled its energy consumption since 2014, indicating that the decisions and actions taken today in Indonesia will have a significant impact on the future fuel consumption. This, in combination with being the largest producer of palm oil in the world, gives it a great potential to be in a leading position in the future production of biofuels, especially biodiesel from palm oil. Additionally, Indonesia has set mandatory targets for biofuel share in the transport sector which indicates that the country also seeks to promote the usages of biofuels. This thesis intends to investigate Indonesia’s potential for biofuel development in the transport sector and which factors that could hinder it. More specifically, this study answers the two questions: (i) Which factors are hampering the development of biofuels in the Indonesian transportation sector from a multi-level perspective? and (ii) What is the projection of the Indonesian transport sector by 2030 in terms of fuel consumption and global warming potential (GWP) and what role could biofuels play in reducing those? The data used were collected by interviews with stakeholders in Indonesia and a literature study, which afterwards was processed with the tools Multi-Level Perspective (MLP) and Long-range Energy Alternatives Planning (LEAP). MLP is a concept aiming to describe how system transitions happens with the help of an examination of the linkages in between technology and society, whereas LEAP is an energy modeling tool used in order to create energy projections in different policy scenario options. In this research, MLP were used to capture and analyze the factors that influence the future implementation of biofuels in Indonesia from a socio-technical perspective, putting forward key barriers for biofuel implementation in Indonesia. LEAP was used to construct a model of the Indonesian transport sector to project the future fuel consumption and GWP emissions. This was used to examine biofuels importance as a fuel through scenarios where different Indonesian policy actions were appraised. Together, these two methods will provide an enlightening and concluding remark on the future possibilities for biofuels in Indonesia's transport sector in this thesis. The major finding of the first research question were that biofuels in Indonesia were being introduced in Indonesia as the government saw economic benefits and a solution to the increased energy demand in Indonesia and an increased energy security in going towards a domestic produced energy source. The need for biofuels were also increased due to an increased global sustainability awareness, which also reached Indonesia. Today, biofuels in Indonesia is in a socio-technical transition pathway to go from a niche innovation to a technology in the regime level, but in order for a breakthrough, a number of barriers needs to be addressed. The most mentioned barriers were the institutional and regulatory barriers, which mainly lays in a lack of cooperation amongst the regulatory institutions and a low rate of success of biofuel laws and regulations. Other barriers were the market barriers, closely connected in a subsidization of fossil fuels in Indonesia and a need for further subsidization of biofuels for the market for biofuels to exist in Indonesia. Furthermore, a technical barrier with the vehicle engine were seen as the engine needs improvements in order for a higher blending of biofuels in the fuel. There was also a concern of the perceived sustainability of biofuels in general (e.g. water scarcity and pollution) which was identified as a hindrance. It was also clear a social change is needed in order to push the biofuel breakthrough and enable it to reach its full potential. Today, the interviewees mainly see a development for the biofuel biodiesel and not for the biofuel bioethanol in Indonesia, which they mainly concluded as there is currently none or very little production and demand for bioethanol in Indonesia, and as well a lack of governmental support for bioethanol development. For the second research question four scenarios were used; Business as Usual (a continuation of current trends), Improved Standards (an investigation of higher emissions standards and an increasing fuel efficiency), Biofuel Mandate (a mandatory biofuel share in fuels) and the Low Carbon scenario (a combination of the previous two as well as introduction of electric vehicles, changed car preferences and higher biofuel blending targets). Cars represents a tenth of the vehicle fleet and the share of diesel car amongst the cars are 5% while gasoline stands for 95%, the rest of the vehicles are gasoline driven motorcycles. The main findings were: the total vehicle fleet will have doubled by 2030. This rapid increase could cause stress on the domestic fuel supply, as the yearly fuel consumption is expected to grow from 770 million GJ in 2014 to 1850 million GJ in 2030, an increase by 140%. In the projection the fossil fuels are blended with biofuels, diesel is mixed with biodiesel while gasoline is blended with bioethanol. The annual diesel fuel consumption is projected to increase from 350 million liters to 1100 million in the Business as Usual scenario where the current trend was expected to continue. The implementation of biodiesel and bioethanol in the Biofuel Mandate scenario. Additionally, the Biofuel Mandate scenario resulted in a 12.6% reduction of GHG emissions during the projected period. The cumulative GHG emissions in the projection is estimated to be 1630 million tonnes of carbon dioxide equivalents in 2030 for the Business as Usual scenario. In the transport sector, gasoline is projected to increase from 23 billion liters to 54 billion liters over the period. In the Improved Standards scenario, where the emission standards are increased from Euro2 to Euro6 in 2030 for cars and Euro4 for motorcycles in 2025 as well as an annual fuel economy improvement of 2%, the total fuel consumption is reduced with 20% and GWP by 18%. It was found that the annual GWP could be reduced by almost 31% below the 2014 level, at 47 million metric tonnes of CO2Eq, if the actions of the Low Carbon scenario were achieved. The barriers associated with the Improved Standards scenario were technical, institutional and regulatory while the Biofuel Mandate scenario also had financial, market and distribution barriers. The Low Carbon scenario had barriers from all of the identified barrier categories. The institutional and regulatory barrier was the most prevailing barrier for all of the scenarios. The recommended actions based on the content of this thesis is to firstly promote collaboration between governmental institutes, stakeholders and authorities and include all stakeholders in the decision progress, this way, frameworks and regulations will have a chance to improve and increase the knowledge about biofuels in all levels. It is also important to implement a stronger biofuel R&D culture, promote a more sustainable biofuel development and increase the public awareness of biofuels. The implementation of biofuels will have a reducing effect on the total GWP and fossil fuel consumption. Gasoline is projected to remain the predominant fuel in the transport sector. Therefore will actions targeting the reduction or substitution of gasoline be more impactful than those towards diesel. However due to the availability and current production capacity of biodiesel there is still potential for higher share of biodiesel in fuels.
113

Analytical and Numerical Models of Multilayered Photonic Devices

Ning, Ding 12 May 2008 (has links)
No description available.
114

Designing order with long-range interactions in mesoscopic magnetic chains

Vantaraki, Christina January 2023 (has links)
This thesis investigates how the low-energy magnetic configuration of a mesoscopic chain can be tuned by geometrical modifications. The magnetic arrays made by single-domain stadium shaped elements positioned side-by-side were fabricated by patterning into a sputtered ferromagnetic thin film. The thickness of the thin film was determined by X-ray reflectivity measurements while Scanning Electron Microscopy and Atomic Force Microscopy were used to characterize the surface morphology of the nanostructures. Magnetic Force Microscopy was used to image the magnetic configuration of mesoscopic chains after applying a thermal annealing protocol and a field demagnetization protocol. By gradually modifying the geometrical arrangement of the half of mesospins, the magnetic chain is found to exhibit a transition from antiferromagnetic to dimer antiferromagnetic configuration after the thermal annealing treatment. After the field demagnetization protocol, both antiferromagnetic and dimer antiferromagnetic domains are formed. Micromagnetic simulations were performed to investigate how the interaction between the mesospins is affected by the geometrical modifications and a qualitative method was invented to examine the theoretical low-energy state of the magnetic chains. It is found that the low-energy magnetic configuration of the mesoscopic arrays is formed after the competition and collaboration of different interactions and is the one observed after the thermal annealing treatment.
115

Graph Homomorphisms: Topology, Probability, and Statistical Physics

Martinez Figueroa, Francisco Jose 11 August 2022 (has links)
No description available.
116

Untersuchung des Gens PMS2 und des Pseudogens PMS2CL bei Patienten mit HNPCC

Andres, Friederike 04 November 2022 (has links)
Background: The hereditary nonpolyposis colorectal cancer (HNPCC, Lynch syndrome) is the most frequent hereditary colorectal cancer syndrome. It has been associated with different types of cancers besides the early onset of the disease. To define HNPCC the Amsterdam or Bethesda criteria have to be met. Causative for the Lynch syndrome is a germline mutation of one of the four mismatch repair genes MLH1, MSH2, MSH6 and PMS2. The detection of pathogenic alterations is of vital importance for the patient as well as for their relatives. The analyses for the PMS2 gene have been severely complicated by the presence of multiple pseudogenes with high homologies to the gene especially in its 5 ́-region. The PMS2CL pseudogene has a high homology to the 3 ́-region of PMS2, in particular the exons 9 and 11- 15, which result in recombination events between the paralogues. Objectives: In this study, we established the newly developed technique of long-range-PCR for mutation detection within the PMS2 gene. Using this method we could clearly discriminate gene from pseudogene which makes it a significant advancement in the detection of pathogenic mutations in PMS2 compared to previously used methods. Until recently mutation detections had been performed with a method, which is now obsolete. It has been the aim of this study to implement the new method of long-range-PCR in the daily diagnostic routine. However, within the study we examined only exons 11-15 of PMS2 equal to the long-range-PCR product 3, because this region contains the highly homologous region to the PMS2CL pseudogene and is known to undergo recombination. Furthermore, it was the aim of this study to make a statement about occuring recombination events and their nature, frequency and consequences. The sequence of the pseudogene has been amplified as well. Methods: Patients were selected based on an isolated loss for PMS2 in the immunohisto- chemistry of their tumor. The long-range-PCR was performed on DNA from blood leukocytes. The amplicons of both the gene and pseudogene were confirmed on gel electrophoresis and used as template for ensuing exon-specific nested-PCR prior to sequencing. Multiplex ligation-depend amplification (MLPA) was performed to screen for deleterious alterations. Results: The study comprised 23 patients. We identified pathogenic mutations in 14 patients (61 %). Four of these mutations are located in the 5 ́-region (upstream exon 8), ten mutations were found in the 3 ́-region (downstream exon 9). Those mutations were nearly evenly distrib- uted over the exons 11-14, whereas two mutations in exon 14 were large deletions. There was no mutation found in exon 15. Moreover we identified one putative pathogenic mutation in exon 12. The second part of this study aimed at the analysis of recombination events between PMS2 and PMS2CL. We identified 27 paralogous sequence variants, which were classified by un- derlying recombination patterns. We found patients without any recombination as well as re- combination events encompassing the exons 13-15. In 14 of 23 patients (61 %) a recombination event could be confirmed occurring primarily in the exons 13-15. The overall number of recombination events are benign and consequences for cancer development are not clear, except one patient who presented with a malignant tumor and carried a sequence recombina- tion in exon 11, which had not been found in former studies. Conclusion: From now on the long-range-PCR should be gold standard for detection of path- ogene alterations in the PMS2 gene. The mechanism and the verification of recombination events encompassing the whole gene PMS2 should be point of interest in further studies.
117

Conformational Communication Through Ortho-Phenylene Oligomers

Devkota, Govinda Prasad 17 July 2023 (has links)
No description available.
118

Filling the gap Within Micromobility : Prototype of a Small Efficient Foldable Electric Vehicle With Long Range / Prototyp av ett litet effektivt el-fordon som kan uppnå lång räckvidd

Lien-Oscarsson, Fredrik January 2023 (has links)
Micromobility has been on the rise lately with a vast catalogue of electric vehicles reaching the market. Electric scooters, mopeds, bikes, one-wheelers and other vehicles have become the norm in everyday life. Most of these vehicles are meant to replace smaller modes of transport such as ordinary bicycles and skateboards. They are designed to complete the last part of one’s commute or for travelling shorter distances. There is; however, a gap within this segment. There is currently no electric micromobility vehicle on the market that is small and lightweight that has a long enough range to compete with ordinary two-tonne cars for longer commutes. This project aims to remedy this by presenting a solution as well as building a prototype of said solution. The electric vehicle that was built for this project is foldable. The design, when folded, is intended to resemble a large, rollable, suitcase. The overall size of the vehicle when folded is only 700x500x400 mm. When unfolded, it is large enough to seat one person fully enclosed. The top speed is limited to 25 km/h and the maximum range per charge is above 100 km. The prototype weighs 29 kg and is able to carry 95 kg. This thesis proves that it is possible to make small and lightweight electric vehicles that can rival traditional cars when it comes to commuting. These vehicles would reduce emissions, congestion and the need for parking space while also being a cheaper alternative for the end user. / Mikromobilitet segmentet har växt avsevärt de senaste åren. En stor samling av olika elektriska fordon så som elskotrar, mopeder, cyklar och enhjulingar, med fler, har blivit en del av vardagen. De flesta av dessa fordon är skapta för att tilryggalägga kortare sträckor. De är ämnade att ersätta cyklar eller att färdas till fots. Det finns dock ingen produkt inom det här segmentet tillgänglig på marknaden som är designad för att kunna tillryggalägga längre sträckor medans den fortfarande är liten och bärbar. Ett sådant fordon presenteras i denna avhandling som lösning på detta problem. Dessutom konstruerades en prototyp av det föreslagna fordonet för att bevisa att det är möjligt att göra små elektriska fordon med lång räckvidd. Prototypen som tillverkades i denna avhandling är vikbar, vilket gör den lätt att transportera när den inte är i bruk. Hela fordonet viks ihop till en resväska som kan dras på bakhjulen. Den har en ihopvikt storlek av 700x500x400 mm, maxhastighet på 25 km/h och väger 29 kg. Detta fordon kan fullständigt innesluta en person när den är utfälld, bära upp till 95 kg och har en räckvidd på över 100 km per laddning. Fordon likt prototypen i denna avhandling kan hjälpa till med att minska utsläpp, minska behovet av parkeringsplatser och minska stockning på vägarna. Dessutom skulle ett sådant fordon också vara mer ekonomisk för slutanvändaren när det kommer till pendling jämfört med en traditionell bil.
119

Long-Range Interactions in Biomolecular-Inorganic Assemblies

Dryden, Daniel M. 29 August 2014 (has links)
No description available.
120

Long-range Interactions and Second Virial Coefficients of Biomolecular Materials

Ma, Yingfang 09 February 2015 (has links)
No description available.

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