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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

Double-Difference Tomography Applied to Monitoring of Geologic Carbon Sequestration in the Aneth Oil Field, Utah

Slaker, Brent 11 January 2012 (has links)
Double-difference seismic tomography is performed on a carbon sequestration operation in the Aneth Oil Field in southeast Utah as part of a Department of Energy initiative on monitoring, verification, and accounting of sequestered CO2. A total of 1,211 seismic events were recorded from a borehole array of 22 geophones. Aneth Unit data were divided into four time periods for time-lapse analysis. A low velocity zone spanning the lateral extents of the observable region, likely representing a CO2 plume, is detected when considering voxels containing the highest ray path coverage. A series of synthetic tomography tests simulating different CO2 plume sizes and locations was performed to assist in characterizing velocity changes associated with Aneth Unit data. Inferences about the existence of a CO2 plume should be made by comparing actual data to synthetic data resulting from simulations performed under similar conditions. Considering synthetic simulation similarities and a derivative weight sum analysis, a CO2 plume can be imaged within the Desert Creek reservoir, but the resolution of the CO2 plume is too low for proper monitoring, verification, and accounting of injected CO2. Recommendations, for improving CO2 plume resolution through double difference seismic tomography, are made to increase the ray path distribution throughout the Aneth Unit by varying geophone locations. / Master of Science
112

Är det efternamnet eller prestationerna som avgör betyget? : Om etnisk diskriminering vid jämförelser av betyg före och efter anonymiseringen av salstentamina vid Stockholms universitet

Gustafsson, Peter, Hed, Anders January 2014 (has links)
Studiens syfte är att undersöka om det förekommer etnisk diskriminering vid bedömningar av salstentamina. Vi frågar om studenters prestationer bedöms olika på grund av etnisk tillhörighet och om graden av etnisk diskriminering skiljer sig mellan kvinnor och män. Stockholms universitet införde anonyma salstentamina höstterminen 2009 med undantag för juridiska fakulteten som tillämpat anonyma tentamina sedan 1999. Vi använder data bestående av betygslistor från tre stora delkurser inom ämnena juridik, nationalekonomi och statsvetenskap vid Stockholms universitet som sträcker sig från höstterminen 2007 till och med vårterminen 2013 (N=12014). Etnicitet har klassificerats utifrån studenternas efternamn. Vår empiriska strategi för att mäta diskriminering baseras på en design som kallas difference-in-difference-in-difference där vi jämför den genomsnittliga förändringen i sannolikheten att antingen bli minst godkänd eller erhålla ett högre betyg före och efter anonymiseringen mellan studenter med skandinaviska och utomskandinaviska efternamn. Vi inkluderar jurister som kontrollgrupp i syfte att kontrollera för betygstrender som sker oberoende av anonymiseringen. I genomsnitt sjönk betygsmedelvärdena i samband med anonymiseringen, framförallt blir det svårare att erhålla ett högt betyg. En tänkbar förklaring till resultaten är att relationen mellan examinator och student distanseras ytterligare vid en anonymisering vilket leder till en mer strikt bedömning. Mot förväntan indikerar resultaten att anonymiseringen har en negativ effekt för manliga studenter med utomskandinaviska efternamn omvänd diskriminering utövas mot manliga studenter med utomskandinaviska efternamn vid en icke-anonym bedömning. Detta förklarades till stor del av att män inom kontrollgruppen med utomskandinaviska efternamn förbättrade sina resultat i samma tidsperiod. Vi finner även att kvinnor med skandinaviska namn i genomsnitt minskar sin sannolikhet att bli väl godkända. Den negativa effekten av anonymiseringen är dock inte signifikant skild mellan kvinnor och män. Resultaten antyder att diskriminering är ett kontextbaserat fenomen.
113

Kulturelle Fremdheit und sexuelle Differenz in Prosatexten von Yoko Tawada

Fischer, Sabine January 2001 (has links)
No description available.
114

Pore scale modeling of rock transport properties

Victor, Rodolfo Araujo 14 October 2014 (has links)
The increasing complexity of oil and gas reservoirs has led to the need of a better understanding of the processes governing the rock properties. Traditional theoretical and empirical models often fail to predict the behavior of carbonates, tight gas sands and shale gas, for example. An essential part of the necessary investigation is the study of the phenomena occurring at the pore scale. In this direction, the so-called digital rock physics is emerging as a research field that offers the possibility of imaging the rock pore space and simulating the processes therein directly. This report describes our work on developing algorithms to simulate viscous and electric flow through a three dimensional Cartesian representation of the porous space, such as those available through X-ray microtomography. We use finite differences to discretize the governing equations and also propose a new method to enforce the incompressible flow constraint under natural boundary conditions. Parallel computational codes are written targeting performance and computer memory optimization, allowing the use of bigger and more representative samples. Results are reported with an estimate of the error bars in order to help on the simulation appraisal. Tests performed using benchmark samples show good agreement with experimental/theoretical values. Example of application on digital modeling of cement growth and on multiphase fluid distribution are also provided. The final test is done on Bentheimer, Buff Berea and Idaho Brown sandstone samples with available laboratory measurements. Some limitations need to be investigated in future work. First, the computer potential fields show anomalous border effects at the open boundaries. Second, a minor problem arises with the decreased convergence rate for the velocity field due to the increased number of operations, leading to the need of a more sophisticated preconditioner. We intend to expand the algorithms to handle microporosity (e.g. carbonates) and multiphase fluid flow. / text
115

The development and characterisation of a conformal FDTD method for oblique electromagnetic structures

Hao, Yang January 1998 (has links)
No description available.
116

"Well I've Reason to Believe, We All Have Been Deceived": Proposition 187, Racist Discourse, and Resistance

García, Rogelio January 1996 (has links)
This paper analyzes racist discourse resulting from and related to California's Proposition 187. Contrary to the views of politicians and economists, I maintain that 187 is indeed a racist measure designed to prevent the entry of people of color, mostly Latinos, into California. Analyses of racist discourse should be contextualized within issues of power, cultural difference, space, culture, and nationalism. After outlining theories of racism, I use Teun van Dijk's work on racist discourse to analyze some of the discursive strategies employed in relation to Proposition 187. The next section discusses the discourse of resistance in Tucson, Arizona and California. Some attention is given to the symbolic violence against Latinos. I argue that discourse cannot be separated from the material world in which it is practiced.
117

Vortex density motion in a cylindrical type II superconductor subject to a transverse applied magnetic field

Claisse, J. R. January 2000 (has links)
No description available.
118

Numerical modelling of inclined seams

Nejad, Mehdi Afsari January 1998 (has links)
No description available.
119

Cross-cultural management in international construction projects : Case study of China Machinery Industry Construction Group Inc.

Liu, Yuan, You, Li January 2014 (has links)
ABSTRACT Title: Cross-cultural management in international construction projects: Case study of China Machinery Industry Construction Group Inc. Level: Final assignment for Master Degree in Business Administration Author: Yuan Liu, You Li Supervisor: Aihie Osarenkhoe Examinor: Maria Fregidon-Malama Date: 2014.04.18 Aim : This study presents the characteristic and current status of the international construction projects, and figure out which barriers caused by cross-cultural differences the multinational corporations and enterprise would face, as well as the solutions for these barriers. Method: This study was carried out by using a qualitative and quantitative research method. We gathered relevant information by conducting questionnaire to Chinese employees working in Congo, Rep and interviews which include four managers of China Machinery Industry Construction Group Inc (CMICGI). By comparing the literature review and finding, we find barriers caused by cross cultural differences and relevant solutions. Result & Conclusions : Through the literature review associating with the analysis of the questionnaire and interview, we find out that there are nine barriers in the project, the reason why they appeared and how them influence the projects. We also find solutions to solve the barriers. Suggestions for future research: This study restricted to geographical and time, it only included one company and one country. More cases can be concluded in future research. Contributions for the study: The study results show how barrier case of cross-cultural different impact in international construction project. We also - 3 - contribute the evaluation for each barrier. Cultural differences between multinational trading are frequently neglected by firms but have a significant impact. Our research can help more companies to find some problems which they usually ignored. KEYWORDS — Cross-cultural management, Barriers, Cross-cultural difference, International construction projects, Identification, Evaluation
120

AR modeling of coherence in time delay and Doppler estimation

Lee, Jun 12 1900 (has links)
Approved for public release; distribution is unlimited / The estimation of time delay and Doppler difference of a signal arriving at two physically separated sensors is investigated in this thesis. Usually, modified cross power spectrum coupled with Doppler compensation is used to detect a common, passive signal received at two separated sensors. Another successful approach uses the cross coherence to achieve this goal. This thesis modifies these two techniques to model the Doppler difference via an autoregressive (AR) technique. Analytical results are derived and experimentally verified via a computer simulation. Performance at high and low signal to noise ratios (SNRs) is examined. / http://archive.org/details/armodelingofcohe00leej / Captain, Korea Air Force

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