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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.
211

Myten om Palme : En texttolkning av dokumentären Palme och dess skildring av det sociala minnet efter Olof Palme som norm eller anomali / The Myth of Palme : a textual analysis of the documentary Palme and its description of the social memory of Olof Palme as a norm or anomaly

Svanström, Emma January 2013 (has links)
”The myth of Palme- a textual analysis of the documentary Palme and its description of the social memory of Olof Palme as a norm or anomaly” by Emma Svanström aims to analyze how the directors of the documentary Palme choose to present Olof Palme to the future generations. Also the goal is to find out if their version presents Palme as a person who followed the norms or was divergent. To this purpose the thesis use textual analysis combined with a quantitative method in search of which persons the directors give the right to form the myth of Palme and which keywords they use to do describe him. To view the film as a social memory in the transformation to a myth the thesis use Jan Assmans theory of social memory and to find out if the documentary describes Palme as following the norms or divergent it uses Mary Douglas theory of anomaly. The results show that it is mainly the narrator and Olof Palme that gets to form the myth of him but also his family, friends, fellow employees and other persons that met him or was affected by his actions. Palme is discribed as special, intelligent, interested in social politics and able to act as he saw fit even if it was against the norms. He is above all described as a complex person with many and sometimes contradicting sides. Some of these actions and characteristics’ are viewed as following the norms while others are shown as anomalies.
212

Solar Panel Anomaly Detection and Classification

Hu, Bo 11 May 2012 (has links)
The number of solar panels deployed worldwide has rapidly increased. Solar panels are often placed in areas not easily accessible. It is also difficult for panel owners to be aware of their operating condition. Many environmental factors have negative effects on the efficiency of solar panels. To reduce the power lost caused by environmental factors, it is necessary to detect and classify the anomalous events occurring on the surface of solar panels. This thesis designs and studies a device to continuously measure the voltage output of solar panels and to transmit the time series data back to a personal computer using wireless communication. A program was developed to store and model this time series data. It also detected the existence of anomalies and classified the anomalies by modeling the data. In total, ten types of anomalies were considered. These anomaly types include temporary shading, permanent shading, fallen leaves, accumulating snow and melting snow among others. Previous time series anomaly detection algorithms do not perform well for reallife situations and are only capable of dealing with at most four different types of anomalies. In this work, a general mathematical model is proposed to give better performance in real-life test cases and to cover more than four types of anomalies. We note that the models can be generalized to detect and to classify anomalies for general time series data which is not necessarily generated from solar panel. We compared several techniques to detect and to classify anomalies including the auto-regressive integrated moving average model (ARIMA), neural networks, support vector machines and k-nearest-neighbors classification. We found that anomaly classification using the k-nearest-neighbors classification was able to accurately detect and classify 97% of the anomalies in our test set. The devices and algorithms have been tested with two small 12-volt solar panels.
213

PE and EV/EBITDA Investment Strategies vs. the Market : A Study of Market Efficiency

Persson, Eva, Ståhlberg, Caroline January 2007 (has links)
Background: The efficient market hypothesis states that it is not possible to consistently outperform the overall stock market by stock picking and market timing. This is because, in an efficient market, all stock prices are at their correct level, and there are no over- or undervalued stocks. Nevertheless, deviations from true price can occur according to the hypothesis, but when they do they are always random. Thus, the only way an investor can perform better than the overall stock market is by being lucky. However, the efficient market hypothesis is very controversial. It is often discussed within the area of modern financial theory and there are strong arguments both for and against it. Purpose: The purpose of this study was to investigate whether it is possible to outperform the overall stock market by investing in stocks that are undervalued according to the enterprise multiple (EV/EBITDA), and the price-earnings ratio. Realization of the Study: Portfolios were constructed based on information from five years, 2001 to 2005. Each year two portfolios were put together, one of them consisting of the six stocks with the lowest price-earnings ratio, and the other consisting of the six stocks with the lowest EV/EBITDA. Each portfolio was kept for one year and the unadjusted returns as well as the risk adjusted returns of the portfolios were compared to the returns on the two indexes OMXS30 and AFGX. The sample consisted of the 30 most traded stocks on the Nordic Stock Exchange in Stockholm 2006. Conclusion: The study shows that it is possible to outperform the overall stock market by investing in undervalued stocks according the price-earnings ratio and the EV/EBITDA. This indicates that the market is not efficient, even in its weak form.
214

Application of Marine Magnetometer for Underwater Object Exploration: Assessment of Depth and Structural Index

Chang, En-Hsin 31 July 2012 (has links)
Magnetic survey is a common geophysical exploration technique. By measuring the magnetic field strength at specific area, the characteristics and physical meaning of the target can be obtained through the analysis of the Earth's magnetic field anomalies within a stratigraphic zone or archaeological sites. In recent years, the marine magnetometer is employed to conduct underwater archaeological expedition at surrounding waters of Taiwan for ancient shipwrecks researching. The purpose of this study is to understand the relationship between the magnetic anomalies with the magnetic object via the various signal processing methods, included the calculation horizontal and vertical derivatives using fast Fourier transform (FFT) to eliminate the regional magnetic influence and gain the anomalies characteristics of the target itself, as well as highlight the location and boundaries of the magnetic source through the analytical signal. In addition, the Euler deconvolution implements as a tool for magnetic source inversion. The theory of Euler deconvolution was first proposed by Thompson (1982), this method is able to detect the magnetic source and estimate its locations by choosing the suitable structural index. Hsu (2002) proposed the enhanced Euler deconvolution, which is a combined inversion for structural index and source location through the use of the vertical derivative of measured data.In this study, we first generate various anomalies as testing models which are correspond with different geometric shape of magnetic source, the position and structural index for model is inversed by enhanced Euler deconvolution in both 2D and 3D.Moreover, the experiment was planned at offshore of Dalinpu in Kaohsiung, we took the CPC's pipelines as investigation objects which were buried under the seabed, than compare with sub-bottom profiler data to assess the feasibility of this method for underwater exploring applications.The most estimated results in 2D are correspond to the theory, but it does not have significant results in 3D due to the lack of observed data for the whole surface.In general, this method is concise and fast, it is fit for interpreting the magnetic data for exploring the underwater object.
215

Eta-eta Prime Mixing In Chiral Perturbation Theory

Kokulu, Ahmet 01 September 2008 (has links) (PDF)
Quantum Chromodynamics (QCD) is believed to be the theory of strong interactions. At high energies, it has been successfully applied to explain the interactions in accelerators. At these energies, the method used to do the calculations is perturbation theory. But at low energies, since the strong coupling constant becomes large, perturbation theory is no longer applicable. Hence, one needs non-perturbative approaches. Some of these approaches are based on the fundamental QCD Lagrangian, such as the QCD sum rules or lattice calculations. Some others use an effective theory approach to relate experimental observables one to the other. Chiral Perturbation Theory (ChPT) is one of these approaches. In this thesis, we make a review of chiral perturbation theory and its applications to study the mixing phenomenon between the neutral pseudoscalar mesons eta and eta-prime.
216

An Extensible Framework For Automated Network Attack Signature Generation

Kenar, Serkan 01 January 2010 (has links) (PDF)
The effectiveness of misuse-based intrusion detection systems (IDS) are seriously broken, with the advance of threats in terms of speed and scale. Today worms, trojans, viruses and other threats can spread all around the globe in less than thirty minutes. In order to detect these emerging threats, signatures must be generated automatically and distributed to intrusion detection systems rapidly. There are studies on automatically generating signatures for worms and attacks. However, either these systems rely on Honeypots which are supposed to receive only suspicious traffic, or use port-scanning outlier detectors. In this study, an open, extensible system based on an network IDS is proposed to identify suspicious traffic using anomaly detection methods, and to automatically generate signatures of attacks out of this suspicious traffic. The generated signatures are classified and fedback into the IDS either locally or distributed. Design and proof-of-concept implementation are described and developed system is tested on both synthetic and real network data. The system is designed as a framework to test different methods and evaluate the outcomes of varying configurations easily. The test results show that, with a properly defined attack detection algorithm, attack signatures could be generated with high accuracy and efficiency. The resulting system could be used to prevent early damages of fast-spreading worms and other threats.
217

<14>^C anatomy of algae in inland ponds and lakes, Antarctica

高橋, 浩, Takahashi, Hiroshi A., 和田, 秀樹, Wada, Hideki, 中村, 俊夫, Nakamura, Toshio, 三浦, 英樹, Miura, Hideki 03 1900 (has links)
第11回名古屋大学タンデトロン加速器質量分析計シンポジウム(平成10 (1998)年度)報告 名古屋大学タンデトロン加速器質量分析計第1号機の研究実績と1号機,2号磯の利用計画
218

Relative motion history of the Pacific-Nazca (Farallon) plates since 30 million years ago [electronic resource] / by Douglas T. Wilder.

Wilder, Douglas T. January 2003 (has links)
Title from PDF of title page. / Document formatted into pages; contains 105 pages. / Thesis (M.S.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: Relative plate motion history since 30 Ma between the Pacific and the southern portion of the Nazca (Farallon) plates is examined. The history is constrained by available seafloor magnetic anomaly data and a two-minute grid of predicted bathymetry derived from satellite altimetry and shipboard sensors. These data are used to create a new plate motion reconstruction based on new magnetic anomaly identifications and finite poles of motion. The new identified magnetic isochrons and tectonic reconstruction provides greater resolution to the tectonic history between chrons 7y (24.73 Ma) and 3 (4.18 Ma) than previous interpretations. Shipboard magnetics and aeromagnetic data from over 250 expeditions were plotted and used to extrapolate magnetic anomalies picked from 2D magnetic modeling from selected cruises. Magnetic anomalies were further constrained by tectonic features evident in the predicted bathymetry. / ABSTRACT: Previously published magnetic anomaly locations consistent with this work were used where interpretation could not be constrained by 2D modeling and map extrapolation. Point locations for anomalies were used as input for calculation of finite poles of motion for chrons 10y, 7y, 6c, 5d, 5b, 5aa, 5o, 4a and 3a. An iterative process of anomaly mapping, pole calculation and anomaly point rotations was used to refine the finite poles of motion. Eleven stage poles were calculated from the nine finite poles from this study and two published instantaneous Euler vectors. Tectonic reconstructions indicate a history dominated by two major southward ridge propagation events, the first starting by 28 Ma and completed by 18 Ma. The second event initiated in association with breakup of the Farallon plate around 24 Ma and ceased by about 11 Ma. Lithosphere was transferred from Nazca to Pacific during the first event and in the opposite sense during the second. / ABSTRACT: Development of the Mendoza microplate east of the later propagator occurred at about 20 Ma and this dual spreading process appears to have lasted until about 15 Ma. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.
219

Optimized Correlation of Geophysical And Geotechnical Methods In Sinkhole Investigations: Emphasizing On Spatial Variations In West-Central Florida

Kiflu, Henok Gidey 01 January 2013 (has links)
Abstract Sinkholes and sinkhole-related features in West-Central Florida (WCF) are commonly identified using geotechnical investigations such as standard penetration test (SPT) borings and geophysical methods such as ground penetrating radar (GPR) and electrical resistivity tomography (ERT). Geophysical investigation results can be used to locate drilling and field testing sites while geotechnical investigation can be used to ground truth geophysical results. Both methods can yield complementary information. Geotechnical investigations give important information about the type of soil, groundwater level and presence of low-density soils or voids at the test location, while geophysical investigations like GPR surveys have better spatial coverage and can resolve shallow stratigraphic indicators of subsidence. In GPR profiles collected at 103 residential sites in covered-karst terrain in WCF, sinkhole-related anomalies are identified using GPR and SPT methods. We analyze the degree to which the shallow features imaged in GPR correlate spatially with the N-values (blow counts) derived from SPTs at the 103 residential sites. GPR anomalies indicating sinkhole activity are defined as zones where subsurface layers show local downwarping, discontinuities, or sudden increases in amplitude or penetration of the GPR signal. "Low SPT values" indicating sinkhole activity are defined using an optimization code that searched for threshold SPT value showing optimum correlation between GPR and SPT for different optimal depth ranges. We also compared these criteria with other commonly used geotechnical criteria such as weight of rod and weight of hammer conditions. Geotechnical results were also used to filter the data based on site characteristics such as presence of shallow clay layers to study the effectiveness of GPR at different zones. Subsets of the dataset are further analyzed based on geotechnical results such as clay thickness, bedrock depth, groundwater conditions and other geological factors such as geomorphology, lithology, engineering soil type, soil thickness and prevalent sinkhole type. Results are used to examine (1) which SPT indicators show the strongest correlations with GPR anomalies, (2) the degree to which GPR surveys improve the placement of SPT borings, and (3) what these results indicate about the structure of sinkholes at these sites. For the entire data set, we find a statistically significant correlation between GPR anomalies and low SPT N-values with a confidence level of 90%. Logistic regression analysis shows that the strongest correlations are between GPR anomalies and SPT values measured in the depth range of 0-4.5 m. The probability of observing a GPR anomaly on a site will decrease by up to 84% as the minimum SPT value increases from 0 to 20 in the general study area. Boreholes drilled on GPR anomalies are statistically significantly more likely to show zones of anomalously low SPT values than boreholes drilled off GPR anomalies. We also find that the optimum SPT criteria result in better correlation with GPR than other simple commonly used geotechnical criteria such as weight of rod and weight of hammer. Better correlations were found when sites with poor GPR penetrations are filtered out from the dataset. The odds ratio showed similar result while the result varied with the depth range, statistics and threshold SPT value (low N- value with optimum correlation), with a maximum observed odds ratio of 3. Several statistical results suggest that raveling zones that connect voids to the surface may be inclined, so that shallow GPR anomalies are laterally offset from deeper zones of low N-values. Compared to the general study area, we found locally stronger correlation in some sub-regions. For example, the odds ratio found for tertiary hawthorn subgroup were 25 times higher than the odds ratio found for the general study area (WCF).
220

Short and Long Term Volcano Instability Studies at Concepción Volcano, Nicaragua

Saballos, Jose Armando 01 January 2013 (has links)
Concepción is the most active composite volcano in Nicaragua, and is located on Ometepe Island, within Lake Nicaragua. Moderate to small volcanic explosions with a volcanic explosivity index (VEI) of 1-2 have been characteristic of this volcano during the last four decades. Although its current activity is not violent, its volcanic deposits reveal stages of violent activity involving Plinian and sub-Plinian eruptions that deposited vast amounts of volcanic tephra in the Atlantic Ocean. These observations, together with the 31,000 people living on the island, make Concepción volcano an important target for volcanological research. My research focuses on the investigation of the stability of the volcano edifice of Concepción, using geophysical data such as gravity, geodetic global positioning system (GPS), sulphur dioxide (SO2) flux, real-time seismic amplitude (RSAM), and satellite remotely-sensed data. The integration of these data sets provides information about the short-term behavior of Concepción, and some insights into the volcano's long-term behavior. This study has provided, for the first time, information about the shallow dynamics of Concepción on time scales of days to weeks. I furnish evidence that this volcano is not gravitationally spreading in a continuous fashion as previously thought, that its bulk average density is comparable to that of a pile of gravel, that the volcano edifice is composed of two major distinctive lithologies, that the deformation field around the volcano is recoverable in a matter of days, and that the deformation source is located in the shallow crust. This source is also degassing through the relatively open magmatic conduit. There are, however, several remaining questions. Although the volcano is not spreading continuously there is the possibility that gravitational spreading may be taking place in a stick-slip fashion. This has important implications for slope stability of the volcano, and the associated hazards. The factors influencing the long term slope stability of the volcano are still not fully resolved, but internal volcanic processes and anthropogenic disturbances appear to be the major factors.

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