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Jansen, Hiske Yolande Mariëlle. "Stuck in a revolving door secularism, assimilation and democratic pluralism /." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2006. http://dare.uva.nl/document/90694.
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Le, Andrew Nguyen. "Assimilating through social networks? The importance of networks in assimilation trajectories." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42483.
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The assimilation outcomes of second generation youths have been hotly debated amongst scholars (Alba et al. 2011, Haller et al. 2011). While the outcomes are contested, it is undeniable that ethnic organizations play a central role in the second generation’s assimilation trajectory. Zhou and Bankston (1998) suggest that participating in ethnic religious institutions promotes upward assimilation through instilling an ethnic identity onto youths. My research on the greater Seattle area Vietnamese Buddhist youth organizations uncovered similar mechanisms that led to Zhou and Bankston’s overall quantitative findings, but also uncover the importance of resource brokering and networks. Based on 43 in-depth interviews, I find that organization participation promotes upward and downward assimilation, and the friendships formed inside ethnic organizations play a crucial role in assimilation outcomes. My project shows that participation in Buddhist youth groups instills a Vietnamese-American identity on youths and, in turn, this ethnic identity can lead to upward assimilation only if the individual is part of a peer network that promotes normative values. Downward assimilation can be associated with youth group participation if the youths enter peer networks that promote deviant behaviors. These deviant peer networks can supersede the positive effects of the youth organization’s overall influence on the individual.
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Walker, Daryl B. "Project engage - the ministry of assimilation training church leaders to lead the church to assimilate prospects and new members /." Theological Research Exchange Network (TREN), 1996. http://www.tren.com.
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Mizzi, Arthur P., Jr Avelino F. Arellano, David P. Edwards, Jeffrey L. Anderson, and Gabriele G. Pfister. "Assimilating compact phase space retrievals of atmospheric composition with WRF-Chem/DART: a regional chemical transport/ensemble Kalman filter data assimilation system." COPERNICUS GESELLSCHAFT MBH, 2016. http://hdl.handle.net/10150/616998.
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This paper introduces the Weather Research and Forecasting Model with chemistry/Data Assimilation Research Testbed (WRF-Chem/DART) chemical transport forecasting/data assimilation system together with the assimilation of compact phase space retrievals of satellite-derived atmospheric composition products. WRF-Chem is a state-of-the-art chemical transport model. DART is a flexible software environment for researching ensemble data assimilation with different assimilation and forecast model options. DART's primary assimilation tool is the ensemble adjustment Kalman filter. WRF-Chem/DART is applied to the assimilation of Terra/Measurement of Pollution in the Troposphere (MOPITT) carbon monoxide (CO) trace gas retrieval profiles. Those CO observations are first assimilated as quasi-optimal retrievals (QORs). Our results show that assimilation of the CO retrievals (i) reduced WRF-Chem's CO bias in retrieval and state space, and (ii) improved the CO forecast skill by reducing the Root Mean Square Error (RMSE) and increasing the Coefficient of Determination (R2). Those CO forecast improvements were significant at the 95 % level.Trace gas retrieval data sets contain (i) large amounts of data with limited information content per observation, (ii) error covariance cross-correlations, and (iii) contributions from the retrieval prior profile that should be removed before assimilation. Those characteristics present challenges to the assimilation of retrievals. This paper addresses those challenges by introducing the assimilation of compact phase space retrievals (CPSRs). CPSRs are obtained by preprocessing retrieval data sets with an algorithm that (i) compresses the retrieval data, (ii) diagonalizes the error covariance, and (iii) removes the retrieval prior profile contribution. Most modern ensemble assimilation algorithms can efficiently assimilate CPSRs. Our results show that assimilation of MOPITT CO CPSRs reduced the number of observations (and assimilation computation costs) by ∼ 35 %, while providing CO forecast improvements comparable to or better than with the assimilation of MOPITT CO QORs.
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Peubey, Carole. "Assimilation of ENVISAT data in an advanced data assimilation system." Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485367.
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i~to a stratosphere-troposphere version of the Met Office assimilation system, producing one of the first analyses to reproduce the September 2002 split of the Antarctic polar vortex. The aim of the project was to investigate the benefit of assimilating MIPAS retrievals and to assess the Met Office 3D-Var assimilation system by examining its different components. The ozone analysis was found to agree with independent ozone observations through most of the middle and upper stratosphere, biases above 60 hPa being within the range -20% to +10% and typically smaller. More significant positive biases were found in the lower stratosphere and inside the polar vortex. Although ozone amounts are shown to be slightly overestimated by MIPAS retrievals in these same regions, these biases are demonstrated to be caused by shortcomings in the model chemistry and transport. MIPAS data have been shown to have a limited impact on the Met Office temperature analysis, although a ' positive effect was identified at the mesopause. It is shown that MIPAScould bring larger benefits if more realistic background error statistics were used for ozone, especially in the lower stratosphere. Based on an evaluation of these statistics using independent datasets, it is suggested that background error variances should be decreased near the ozone maximum and increased below 70 hPa It is also recommended to introduce latitudedependence in vertical error correlations and height-dependence in horizontal error correlations. Improvements are also proposed to improve the ozone assimilation in the polar vortex region. Finally, analysed winds have been found to induce errOneous transport of ozone by increasing vertical diffusion of ozone and enhancing the mean zonal circulations. This especially affects the tropics, where ozone analyses reveal excessive exchanges of air parcels between the stratosphere and the troposphere.
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Pollock, Edwina Jane Education Faculty of Arts & Social Sciences UNSW. "Assimilating complex information." Awarded by:University of New South Wales. School of Education, 2000. http://handle.unsw.edu.au/1959.4/17813.
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Methods of instruction which are intended to facilitate understanding tend to incorporate all of the elements required for understanding in the instructions. Frequently, these types of instructions may overwhelm a learner???s limited working memory and hinder learning. The five experiments reported in this thesis were generated by cognitive load theory. Cognitive load theory is based on the assumption that features of human cognitive architecture have important implications for how we learn and understand. The experiments examined an alternative approach to instructional design which had the goal of promoting schema construction in order to foster understanding. A two phase, isolated-interacting elements learning approach was developed which, in the first phase, artificially reduced the element interactivity of complex material by presenting the material as isolated elements of information that could be processed serially, rather than simultaneously, in working memory. In the second phase of instruction, all the information for understanding was presented. The control group???s instruction was a more conventional approach to promoting understanding where all the information for understanding was presented in both Phase 1 and 2. Although a possible consequence of artificially reducing the element interactivity of material may be an initial decrease in a student???s capacity for understanding, it was hypothesised that over the longer term it would lead to an increase in learners??? understanding. The results reported in this thesis provide powerful evidence that for certain groups of learners, information is better learnt through the isolated-interacting elements instructional method. Evidence is also provided in support of the proposal that schema construction is the mechanism underlying the success of the isolated-interacting elements instructional method. Experiments 1 and 3 demonstrated that when novice students are required to learn complex information, the isolated-interacting elements method of instruction was superior to the control method. In contrast, no evidence was found in Experiments 2 and 4 to suggest a difference between these instructional techniques. These contrasting results can be explained by the different levels of domain knowledge possessed by the participants of each experiment. The results of Experiment 5 were similar to those of Experiments 1 and 3, namely that students performed superiorly if they had studied the isolated elements followed by interacting elements instruction. These results provide significant theoretical support for the claim that expertise is the key factor implicated in the beneficial effects associated with the isolated-interacting elements instructional technique since the participants in Experiment 5 had previously participated in Experiments 2 and 4. The difference in the outcomes of these experiments can be explained by the level of domain specific knowledge the participants of Experiment 5 had in each of the knowledge domains tested by the various experiments.
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Wu, Jane C. 1977. "Assimilating hybridized architecture." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/30236.
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Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.Includes bibliographical references (p. 106-107).
The thesis searches for means of operation to deal with hybridized architecture. As a conceptual framework, sociology theory appears to be an insightful precedent, for it analyzes and classifies how multiple constituents join together. Sociologist Milton Gordon delineates three assimilation processes; these include Anglo Conformity, Cultural Pluralism, and Melting Pot. From these theories, it is suspected that the Melting Pot model has the most potential for generating unconventional program usage while being the most challenging model in reconciling pre-determined functions. The thesis uses the Melting Pot model as a means of operation to push the limits of assimilating hybridized architecture. Anglo Conformity is when an individual gives up his/her attribute to fit into the larger context. It can be represented as A + B + C = A, assuming A is the majority. Cultural Pluralism also known as the "salad bowl," is when different individuals keep their own qualities while sharing common interests. A + B + C = A + B + C. Melting Pot is when different individuals merge together by absorbing and contributing each individual's quality; out of this interaction comes a new entity.
Jane C. Wu.
M.Arch.
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Barillec, Remi Louis. "Bayesian data assimilation." Thesis, Aston University, 2008. http://publications.aston.ac.uk/15276/.
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This thesis addresses data assimilation, which typically refers to the estimation of the state of a physical system given a model and observations, and its application to short-term precipitation forecasting. A general introduction to data assimilation is given, both from a deterministic and stochastic point of view. Data assimilation algorithms are reviewed, in the static case (when no dynamics are involved), then in the dynamic case. A double experiment on two non-linear models, the Lorenz 63 and the Lorenz 96 models, is run and the comparative performance of the methods is discussed in terms of quality of the assimilation, robustness in the non-linear regime and computational time.
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Ali, A. H. "Nitrate assimilation in yeasts." Thesis, Swansea University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.635757.
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Torres, Javier. "Essays on immigrant assimilation." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44777.
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This dissertation examines immigrants (to Canada) assimilation problems from a perspective of imperfect human capital transferability. Chapter 2 discusses how much of the immigrant wage gap can be explained by the undervaluation of foreign human capital (education and work experience). The identification of the human capital source (using information available in the 2006 Canadian census) can explain up to 70% of the native-immigrant wage gap. The foreign-born dummy coefficient goes from around -11% to close
to -3%. Education acquired in Asia tends to be valued less than education from South America, Africa and East Europe; which in turn is less valued than education from Oceania, the U.S. and the rest of continental Europe. Studying in the UK consistently appears more beneficial than studying in Canada. When incorporating country of origin fixed effects, the different specifications visibly reduce the heterogeneity of country coefficients. The reduction is sizeable for Pakistan, India, China and the Philippines; though their coefficients remain negative. A smaller reduction for Europe, South-East Asia, Hong Kong and the US drives their coefficients close to zero. The UK country of origin dummy has the only persistently positive coefficient. Chapter 3 describes the occupational assimilation process of 2000-2001 immigrants in their first four years. The results show that those with high levels of education experience a more significant decline in their first occupation. Education, though, has a positive and significant effect on occupational improvement; which reduces the size and significance of the negative effect of education on the second occupational gap. It, however, does not change its sign. The same pattern is observed when analyzing occupational gaps through time. Chapter 4 focuses on immigrants' English proficiency improvement. Overall, immigrants show relatively small improvements in language proficiency in the first four years in Canada. Still, those arriving under the family immigrant category with an intermediate or advanced level are less likely to improve and more likely to decrease their English proficiency. Human capital variables (age and education) are also consistently relevant for English proficiency improvement.
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Campbell, Elizabeth M. "Nitrogen assimilation by limpets." Thesis, University of Glasgow, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.479100.
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Gregory, Alastair. "Multilevel ensemble data assimilation." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/60645.
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This thesis aims to investigate and improve the efficiency of ensemble transform methods for data assimilation, using an application of multilevel Monte Carlo. Multilevel Monte Carlo is an interesting framework to estimate statistics of discretized random variables, since it uses a hierarchy of discretizations with a refinement in resolution. This is in contrast to standard Monte Carlo estimators that only use a discretization at a fine resolution. A linear combination of sub-estimators, on different levels of this hierarchy, can provide new statistical estimators to random variables at the finest level of resolution with significantly greater efficiency than a standard Monte Carlo equivalent. Therefore, the extension to computing filtering estimators for data assimilation is a natural, but challenging area of study. These challenges arise due to the fact that correlation must be imparted between ensembles on adjacent levels of resolution and maintained during the assimilation of data. The methodology proposed in this thesis, considers coupling algorithms to establish this correlation. This generates multilevel estimators that significantly reduce the computational expense of propagating ensembles of discretizations through time and space, in between stages of data assimilation. An effective benchmark of this methodology is realised by filtering data into high-dimensional spatio-temporal systems, where a high computational complexity is required to solve the underlying partial differential equations. A novel extension of an ensemble transform localisation framework to finite element approximations within random spatio-temporal systems is proposed, in addition to a multilevel equivalent.
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Archangeli, Diana. "Keley-I Consonant Assimilation." University of Arizona Linguistics Circle, 1987. http://hdl.handle.net/10150/226555.
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Keley-i, a Philippine language, has two rules assimilating consonants across a vowel. Such rules might be taken as evidence against the Morphemic Tier Hypothesis (MTH) and against the Locality Condition (LC). The MTH states (1) Morphemic Tier Hypothesis (MTH) If and only if two segments are members of separate morphemes are those two segments aligned in separate phonological tiers. The Keley-i data suggest that the MTH does not hold universally because consonants assimilate across vowels, which has been taken as evidence for two segmental planes in order to prevent the crossing of association lines. The data also create problems for the Locality Condition: (3) Locality Condition (LC) A phonological rule is applicable only if the target and trigger are adjacent. The consonant features assimilate across an intervening vowel: the target and trigger, being skeletal slots, are not adjacent. I suggest here that adopting the feature hierarchy as proposed in Archangeli and Pulleyblank (1986) (which is a modification of Clements 1985) combined with underspecification theory (Archangeli 1984, Pulleyblank 1986, Archangeli and Pulleyblank 1986) allows an analysis of the Keley -i data which permits maintaining the MTH and the LC. A further result is that the Spreading Hypothesis is maintained as well, thus supporting the hypothesis that phonological assimilation is formally expressed in one manner only, namely by insertion of association lines, and not by feature copy rules. (See Hayes 1986, Archangeli and Pulleyblank 1986.) (4) Spreading Hypothesis Phonological assimilation is expressed only by rules adding association lines. The discussion is organized as follows. First, the feature hierarchy and the theory of underspecification are briefly outlined. I then present a partial analysis of the Keley-i data. The analysis consists of a syncope rule and some rules of consonant assimilation. Finally, I return to the problems that Keley -i presents for the MTH and the LC and propose that the relevant Keley-i data are not only in accordance with the MTH and the LC but predicted by the interaction of the two sub -theories, the Feature Hierarchy and Underspecification.
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Fishman, Jonathan. "Young Adults' Assimilation of Parental Divorce: A Developmental Elaboration of the Assimilation Model." Miami University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=miami1240597649.
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Fishman, Jonathan L. "Young adults' assimilation of parental divorce a developmental elaboration of the assimilation model /." Oxford, Ohio : Miami University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1240597649.
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Haratsis, Jessica Megan. "Assimilative and Accommodative Resources in Young Adults." Thesis, Griffith University, 2015. http://hdl.handle.net/10072/366516.
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The aims of the research program were: (a) to develop and validate new measures to assess assimilative and accommodative resources (cf. Brandtstädter & Rothermund, 2002) in young adults (Study 1), (b) to test the cross-sectional associations among assimilation and accommodation, career goal appraisals and attitudes, career goal engagement and disengagement, and life satisfaction (Study 2), and (c) to investigate the cross-lagged relationships between assimilation and accommodation, career goal attainability and optimism, and well-being over time (Study 3). The studies were informed by the dual-process framework (Brandtstädter & Rothermund, 2002) and are reported as three journal articles that have been accepted for publication in international, peer reviewed journals.
In Study 1, new scales were developed and validated to measure assimilative and accommodative resources in young adults. Existing scales demonstrated poor validity and were developed for use with middle aged to older adults. Experts reviewed the content validity of the two existing measures (Tenacious Goal Pursuit and Flexible Goal Adjustment Scales; Brandtstädter & Renner, 1990) to identify items that could be modelled for the new scales. New items were generated, then refined by an expert panel and focus groups of young adults.Thesis (PhD Doctorate)
Doctor of Philosophy in Clinical Psychology (PhD ClinPsych)
School of Applied Psychology
Griffith Health
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Laurent, Céline D. C. "Studying the assimilative capacity of Loch Creran." Thesis, Edinburgh Napier University, 2009. http://researchrepository.napier.ac.uk/Output/1052699.
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Semi-enclosed coastal systems are of great importance bothenvironmentally and economically. ln recent years, increasedanthropogenic activities in these areas brought the need for integrated, ecosystem-scale management. This study proposes to estimate the assimilative capacity of a small fjord. This study had three main aims. The first one was to compare the pelagic properties observed in the 2000s to those observed at the same site in the 1970s, the second one was to design an accurate but simple, two dimensional dynamic model of a fjordic system for the prediction of chlorophyll and nutrient concentrations, and the third one was to propose a method for the estimation of the assimilative capacity of the fjord. This study was carried out on Loch Creran, a shallow fjord in the Scottish Highlands, in which a large sh farm was established in the 1980s. A sampling campaign was carried out 2003-2004 in order to collect time series of chlorophyll, dissolved inorganic nutrients and particulate organic matter concentrations; temperature, salinity, density and turbidity proles and microplankton and mesozooplankton diversity, abundance and biomass. Similar time series from the 1970s were gathered from the literature. The data from both decades were compared and showed significant changes in some physical, chemical and biological properties. The cessation of activity of an alginate production plant, changes inweather patterns and the introduction of aquaculture were identified as possible causes. A simple two-dimensional, three-box dynamic model of Loch Creran was designed. It has only three state variables (chlorophyll, nitrogen and phosphorus concentrations) and two crucial parameters (the exchange rate and the yield of chlorophyll from nutrients) as well as an optical-photosynthetic sub-model. The model was tested against observations for the years 1975 and 2003 and showed an overall good fit. The model was then run under different scenarios in order to estimate the assimilative capacity of Loch Creran for nitrogen and phosphorus and its carrying capacity for farmed salmon.
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Williams, John Henry Howatson. "Control of assimilate partitioning in crop plants." Thesis, Bangor University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328915.
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Shinkle, Monte L. "New member assimilation a strategy for assimilation in Concord Baptist Church, Jefferson City, Missouri /." Theological Research Exchange Network (TREN), 1994. http://www.tren.com.
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Halm, Hannah. "Nitrogen assimilation by aquatic prokaryotes." Berlin mbv, Mensch-und-Buch-Verl, 2009. http://d-nb.info/100292491X/04.
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Sanz-Alonso, Daniel. "Assimilating data into mathematical models." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/83231/.
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Chapter 1 is a brief overview of the Bayesian approach to blending mathematical models with data. For this introductory chapter, I do not claim any originality in the material itself, but only in the presentation, and in the choice of contents. Chapters 2, 3 and 4 are transcripts of published and submitted papers, with minimal cosmetic modifications. I now detail my contributions to each of these papers. Chapter 2 is a transcript of the published paper Long-time Asymptotics of the Filtering Distribution for Partially Observed Chaotic Dynamical Systems" [Sanz-Alonso and Stuart, 2015] written in collaboration with Andrew Stuart. The idea of building a unified framework for studying filtering of chaotic dissipative dynamical systems is from Andrew. My ideas include the truncation of the 3DVAR algorithm that allows for unbounded observation noise, using the squeezing property as the unifying arch across all models, and most of the links with control theory. I stated and proved all the results of the paper. I also wrote the first version of the paper, which was subsequently much improved with Andrew's input. Chapter 3 is a transcript of the published paper \Filter Accuracy for the Lorenz 96 Model: Fixed Versus Adaptive Observation Operators" [Law et al., 2016], written in collaboration with Kody Law, Abhishek Shukla, and Andrew Stuart. My contribution to this paper was in proving most of the theoretical results. I did not contribute to the numerical experiments. The idea of using adaptive observation operators is from Abhishek. Chapter 4 is a transcript of the submitted paper\Importance Sampling: Computational Complexity and Intrinsic Dimension" [Agapiou et al., 2015], written in collaboration with Sergios Agapiou, Omiros Papaspiliopoulos, and Andrew Stuart. The idea of relating the two notions of intrinsic dimension described in the paper is from Omiros. Sergios stated and proved Theorem 4.2.3. Andrew's input was fundamental in making the paper well structured, and in the overall writing style. The paper was written very collaboratively among the four of us, and some of the results were the fruit of many discussions involving different subsets of authors. Some of my inputs include: the idea of using metrics between probability measures to study the performance of importance sampling, establishing connections to tempering, the analysis of singular limits both for inverse problems and filtering, most of the filtering section and in particular the use of the theory of inverse problems to analyze different proposals in the filtering set-up, the proof of Theorem 4.2.1, and substantial input in the proof of all the results of the paper not mentioned before. This paper aims to bring cohesion and new insights into a topic with a vast literature, and I helped towards this goal by doing most of the literature review involved.
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Tong, Yuying Entwisle Barbara. "Three essays on immigrant assimilation." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2007. http://dc.lib.unc.edu/u?/etd,1426.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2007.Title from electronic title page (viewed Apr. 25, 2008). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Sociology." Discipline: Sociology; Department/School: Sociology.
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Woodgate, Rebecca A. "Data assimilation in ocean models." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359566.
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Moore, A. M. "Data assimilation in ocean models." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375276.
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Percival, James R. "Displacement assimilation for ocean models." Thesis, University of Reading, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501349.
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Advances in numerical ocean modelling have led to increasing interest in data assimilation for the purpose of ocean forecasting. The majority of current assimilation techniques ignore the integral constraints inherent in ocean dynamics, and instead locally insert information from observations in an Eulerian sense. It has been shown that such methods can generate spurious circulations by affecting balance of dynamic ocean tracers. In this thesis techniques are presented which solve a rearrangement problem to perform data assimilation under an integral constraint, effectively performing assimilation in a Lagrangian sense to correct assumed initial phase error. A descent algorithm equivalent to three dimensional variational assimilation is developed for the pure rearrangement problem, based on an advective process acting in pseudo-time. This method is shown to assimilate direct observations successfully, even when observations are only available on a limited subdomain. Two novel modifications which improve the rate of convergence are also discussed.
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Da, Dalt Federico. "Ionospheric modelling and data assimilation." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.665450.
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A New Ionospheric Model (ANIMo) based upon the physics of production, loss, and vertical transport has been developed. The model is driven by estimates of neutral composition, temperature and solar flux and is applicable to the mid-latitude regions of the Earth under quiet and moderate geomagnetic conditions. This model was designed to exhibit specific features that were not easy to find all together in other existing ionospheric models. ANIMo needed to be simple to use and interact with, relatively accurate, reliable, robust and computationally efficient. The definition of these characteristics was mostly driven by the intention to use ANIMo in a Data Assimilation (DA) scheme. DA or data ingestion can be described as a technique where observations and model realizations, called background information, are combined together to achieve a level of accuracy that is higher than the accuracy of the two elements taken separately. In this project ANIMo was developed to provide a robust and reliable background contribution. The observations are given by the Global Positioning System (GPS) ionospheric measurements, collected from several networks of GPS ground-station receivers and are available on on-line repositories. The research benefits from the Multi-Instrument Data Analysis System (MIDAS) [Mitchell and Spencer, 2003; Spencer and Mitchell, 2007], which is an established ionospheric tomography software package that produces three dimensional reconstructions of the ionosphere starting from GPS measurements. Utilizing ANIMo in support of MIDAS has therefore the potential to generate a very stable set-up for monitoring and study the ionosphere. In particular, the model is expected to compensate some of the typical limitations of ionospheric tomography techniques described by Yeh and Raymund [1991] and Raymund et al. [1994]. These are associated with the lack of data due to the uneven distribution of ground-based receivers and limitations to viewing angles. Even in regions of good receiver coverage there is a need to compensate for information on the vertical profile of ionisation. MIDAS and other tomography techniques introduce regularization factors that can assure the achievement of a unique solution in the inversion operation. These issues could be solved by aiding the operation with external information provided by a physical model, like ANIMo, through a data ingestion scheme; this ensures that the contribution is completely independent and there is an effective accuracy improvement. Previously, the limitation in vertical resolution has been solved by applying vertical orthonormal functions based upon empirical models in different ways [Fougere, 1995; Fremouw et al., 1992; Sutton and Na, 1994]. The potential for the application of a physical model, such ANIMo is that it can provide this information according to the current ionospheric conditions. During the project period ANIMo has been developed and incorporated with MIDAS. The result is A New Ionospheric Data Assimilation System (ANIDAS); its name suggests that the system is the implementation of ANIMo in MIDAS. Because ANIDAS is a data ingestion scheme, it has the potential to be used to perform not only more accurate now-casting but also forecasting. The outcomes of ANIDAS at the current time can be used to initialise ANIMo for the next time step and therefore trigger another assimilation turn. In future, it is intended that ANIMo will form the basis to a new system to predict the electron density of the ionosphere – ionospheric forecasting.
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Saletri, Charles E. "Mobilizing God's people for assimilation." Theological Research Exchange Network (TREN), 1994. http://www.tren.com.
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Shukla, Abhishek. "Analysis of data assimilation schemes." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/90880/.
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Data assimilation schemes are methods to estimate true underlying state of the physical systems of interest by combining the theoretical knowledge about the underlying system with available observations of the state. However, in most of the physical systems the observations often are noisy and only partially available. In the first part of this thesis we study the case of sequential data assimilation scheme, when the underlying system is nonlinear chaotic and the observations are partial and noisy. We produce a rigorous and quantitative analysis of data assimilation process for fixed observation modes. We also introduce a novel method of dynamically rearranging observation modes, leading to the requirement of fewer observation modes while maintaining the accuracy of the data assimilation process. In the second part of the thesis we focus on 4DVAR data assimilation scheme which is a variational method. 4DVAR data assimilation is a method that solves a variational problem; given a set of observations and a numerical model for the underlying physical system together with a priori information on the initial condition to estimate the initial condition for the underlying model. We propose a hybrid data assimilation scheme where, we consider the 3DVAR scheme for the model as the constraint on the variational form, rather than constraining the variational form with the original model. We observe that this method reduces the computational cost of the minimization of the 4DVAR variational form, however, it introduces a bias in the estimate of the initial condition. We then explore how the results can be extended to weak constraint 4DVAR.
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Byrnes, Scott WIlliam. "Assimilative domain proficiency and performance in chemistry coursework." ScholarWorks, 2010. https://scholarworks.waldenu.edu/dissertations/735.
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The assimilation and synthesis of knowledge is essential for students to be successful in chemistry, yet not all students synthesize knowledge as intended. The study used the Learning Preference Checklist to classify students into one of three learning modalities -- visual, auditory, or kinesthetic (VAK). It also used the Kolb Learning Style Inventory (KLSI), which utilizes four learning domains - Converging, Accommodating, Diverging, and Assimilating - to explain the students' maturation process by showing shift from any domain towards the Assimilating domain. A shift approaching this domain was considered as improvement in the assimilation and synthesis of knowledge. This pre-experimental one-group pretest-posttest study was used to test the hypothesis that modifying a high school chemistry curriculum to accentuate a student's learning preference would result in a shift towards the Assimilative domain on the KLSI and if there was a correlation between the improvement in student learning and a shift towards the KLSI Assimilating domain. Forty-two high school students were issued the VAK and provided with differentiated instruction via homologous cooperative learning groups. Pre- and post-KLSI and chemistry concepts tests were administered. T test analyses showed no significant shift towards the Assimilating domain. Further Pearson's r analyses showed no significant correlation between the KLSI and exam scores. This study contributes to social change by providing empirical evidence related to the effectiveness infusing learning styles into the science curriculum and the integration of the KLSI to monitor cognitive development as tools in raising standardized test scores and enhancing academic achievement. Results from the study can also inform future research into learning styles through their incorporation into the science curriculum.
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Barsby, Amanda. "Die rol van tolke in onderhoudvoering 'n Sielkundig-sistemiese perspektief en geldigheidsbepaling/." Diss., Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-10172005-152643.
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Detter, Alfred L. "The assessment of newcomer assimilation and the development of an assimilation model at Grace Baptist Church." Theological Research Exchange Network (TREN), 1989. http://www.tren.com.
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Kouki, Rafa. "Enterprise Resource Planning Post-Implementation Assimilation Challenge : An integrative Framework for a Better Post-Implementation Assimilation." Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26287/26287.pdf.
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Cuartero, Torres Néstor. "Voicing Assimilation in Catalan and English." Doctoral thesis, Universitat Autònoma de Barcelona, 2002. http://hdl.handle.net/10803/4908.
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El objetivo de este trabajo es estudiar el proceso de asimilación de sonoridad a diferentes velocidades de habla en catalán e inglés y, más concretamente observar y analizar la asimilación de sonoridad cuando dos consonantes que tienen una especificación fonológica de sonoridad distinta coocurren a través de palabras. Además, el estudio se propone evaluar modelos descriptivos actuales con el fin de determinar cómo explican los datos obtenidos en el experimento. Se realizó un experimento usando datos acústicos, electropalatográficos y electoglotográficos simultáneos. Las secuencias estudiadas son de 4 tipos:
1) Secuencias de obstruyentes donde C1 es fonológicamente sorda y C2 es fonológicamente sonora.
2) Secuencias de obstruyentes donde C1 es fonológicamente sonora y C2 es fonológicamente sorda.
3) Secuencies de sonorante seguida de obstruyente.
4) Secuencias de obstruyente seguida de sonorante.
Se observó que en las secuencias de obstruyentes en catalán los hablantes tienden a anticipar el gesto de sonoridad de C2 a C1, tanto en las secuencias de oclusivas como en las secuencias de fricativa seguida de oclusiva. Así, el proceso es regresivo y categórico, lo cual es congruente con la existencia de una regla de asimilación de sonoridad en catalán. También se observó que los hablantes catalanes pueden mostrar anticipación parcial del gesto de sonoridad de C2, lo cual muestra que la asimilación de sonoridad puede ser un proceso gradual en catalán. Así pues, parece que la regla de asimilación de sonoridad es opcional. Los datos del catalán reflejan dos procesos distintos: por un lado, la asimilación completa y regresiva de sonoridad en las secuencias de obstruyentes es el resultado de una regla que implica la reorganización a alto nivel de las instrucciones motoras. Por otro lado, los casos de asimilación parcial podrían ser debidos a factores de implementación fonética.
En inglés se observó que no existe una regla fonológica de asimilación de sonoridad en las secuencias de obstruyentes. La coordinación de los gestos orales y glotales durante la constricción máxima es un proceso gradual.
En las secuencias que combinan sonorantes y obstruyentes, el gesto de sonoridad coincide con la transición de C1 a C2 en ambas lenguas. Además, se observa que puede haber asimilación completa de sonoridad en las secuencias obstruyente - sonorante en catalán. Esto sugiere que la regla de asimilación regresiva de sonoridad podría extenderse a este tipo de secuencias, por lo menos en algunos hablantes catalanes.
Finalmente, se sugiere que los modelos conocidos como Articulatory Phonology y Windows Theory pueden dar cuenta de la coordinación de los gestos orales y glotales en catalán e inglés.
The present study intends to analyze the process of voicing assimilation across different speaking rates in Catalan and English. More specifically, it aims at observing and characterizing voicing assimilation when two consonants that have a different phonological specification for voicing co-occur across word boundaries. Furthermore, this study intends to evaluate current descriptive frameworks, in order to see how they account for the data obtained in the experiment.
An experiment was carried out using simultaneous acoustic, electroglottographic and electropalatographic data. The sequences were of 4 types:
1) Obstruent sequences where C1 was phonologically voiceless and C2 was phonologically voiced, e.g., 'fat gap', 'this doll'.
2) Obstruent sequences where C1 was phonologically voiced and C2 was phonologically voiceless, e.g., 'sad gap', 'his toll'.
3) Sequences of sonorant plus voiceless obstruent, e.g., 'full cap', 'long sip'.
4) Sequences of voiceless obstruent plus sonorant, e.g., 'thick lap', 'this nut'.
It was found that in Catalan obstruent sequences that differ in their phonological specification for voicing, speakers tend to anticipate the voicing gesture of C2 to C1, both in stop sequences and in fricative - stop sequences. Thus, the process is regressive and categorical, which is congruent with a rule of voicing assimilation in Catalan. Evidence was also found that speakers can display partial anticipation of the voicing gesture of C2, which shows that voicing assimilation may also be a gradient process in this language. Thus, the voicing assimilation rule seems to be optional. The Catalan data thus seem to reflect two different processes. On one hand, complete regressive voicing assimilation in obstruent sequences seems to be the result of a rule involving higher-level reorganization of motor commands. On the other hand, cases of partial assimilation may result from phonetic implementation factors.
In English, it was found that there is no phonological rule of voicing assimilation in obstruent sequences. Rather, the coordination of oral and glottal gestures during the maximal constriction is a gradient process that may result from anticipatory overlap - sensitive to time constraints - and inertial effects .
In sequences of consonants where nasals and laterals combine with obstruents, the voicing gesture seems to be switched at the transition from C1 to C2 in both languages. In addition, evidence was found for complete assimilation of voicing in Catalan obstruent - sonorant sequences, suggesting the extension of the regressive voicing assimilation rule for obstruents to these sequences, at least for some speakers.
Finally, it is suggested that Articulatory Phonology and Keating's Windows Theory account for the coordination of oral and glottal gestures in Catalan and English.
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Lung, Shiu-cheung. "Assimilation of phytate-phosphorus by plants." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B35710986.
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Wackernagel, Hans. "Géostatistique et assimilation séquentielle de données." Habilitation à diriger des recherches, Université Pierre et Marie Curie - Paris VI, 2004. http://tel.archives-ouvertes.fr/tel-00542362.
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La géostatistique spatio-temporelle traditionnelle n'est pas en mesure de décrire adéquatement la dynamique, en général fortement non-linéaire, de processus spatio-temporels multivariables. Pour cela des modèles de transport physico-chimiques sont en général bien mieux adaptés. Cependant, étant donné que ces derniers ne maîtrisent pas totalement la complexité des processus qu'ils cherchent à décrire, soit parce qu'ils sont basés sur des hypothèses simplificatrices, soit parce que l'information servant à établir les conditions initiales et aux limites est imparfaite, il est opportun d'introduire des techniques statistiques servant à les guider pour assimiler un flot de mesures émanant de capteurs automatiques. Des projets récents au Centre de Géostatistique de l'Ecole des Mines de Paris ont permis d'explorer l'application de ces techniques dans le domaine de l'océanographie et en pollution de l'air. Il s'est très vite avéré que la géostatistique offrait des concepts et des approches qui pouvaient contribuer à enrichir les techniques d'Assimilation Séquentielle de Données. La thèse de Laurent Bertino et des publications ultérieures ont permis de développer cette thématique porteuse, dont la présente synthèse établit un compte-rendu.
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Esser, Hartmut. "Ist das Konzept der Assimilation überholt?" Universität Potsdam, 2003. http://opus.kobv.de/ubp/volltexte/2009/3063/.
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Inhalt:
1 Die Assimilation und ihre Alternativen
2 Die Situationslogik der Assimilation
3 Die „Interaktion“ von ethnischer Segmentation und ethnischer Ungleichheit: Das Beispiel der ethnischen Mobilitätsfalle.
4 Perspektiven
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Detert, Neils. "Assimilation in 2+1 brief therapy." Thesis, Open University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269842.
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Jamal, Sheri K. Henderson James W. "Hispanic assimilation to American health insurance." Waco, Tex. : Baylor University, 2006. http://hdl.handle.net/2104/4825.
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Lindskog, Magnus. "On errors in meteorological data assimilation." Doctoral thesis, Stockholm : Department of Meteorology, Stockholm university, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7258.
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Akay, Alpaslan. "Essays on microeconometrics and immigrant assimilation /." Göteborg : Dep. of Economics, School of Business, Economics and Law, Göteborg Univ, 2008. http://www.gbv.de/dms/zbw/566893517.pdf.
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Milewski, Thomas. "Stratospheric chemical-dynamical ensemble data assimilation." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110352.
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Ensemble data assimilation uses Monte-Carlo methods to estimate flow-dependent error covariances which allow the transfer of information from observed variables to correlated ones. As the winds are largely unobserved in the stratosphere and models have biases there, the possibility to constrain the dynamical analysis from temperature or ozone observations is attempted using ensemble data assimilation.The applicability of coupled chemical/dynamical ensemble data assimilation in the stratosphere is tested in idealized perfect model observation system simulation experiments with the IGCM-FASTOC chemistry-climate model. Covariance localization is found to be necessary for stability of the Ensemble Kalman Filter (EnKF) data assimilation system and optimal localization parameters yield a strong constraint on the global dynamical state of the model when assimilating synthetic limb-sounding stratospheric temperature or ozone observations only. The multivariate coupling between ozone, temperature and winds is investigated in the optimized EnKF system. Stratospheric temperature and ozone observations induce valuable dynamical analysis increments during the analysis step. There is additional feedback during the forecast steps in the ensemble data assimilation system, further constraining the global dynamical and ozone states. The potential impact of assimilating observations posterior to analysis time in multivariate mode was estimated with an Ensemble Kalman Smoother (EnKS). Assimilation of additional asynchronous observations up to 48 hours posterior toanalysis time provided improvements on the EnKF analysis nearly similar to the ones obtained from the assimilation of a same amount of additional synchronous observations. The EnKS assimilation showed beneficial impacts on the unobserved variables analysis state but mixed impacts on the observed variable analysis state.The capacity to constrain the unobserved stratospheric winds by assimilating ozone observations is demonstrated in the ensemble data assimilation system with the EnKF and EnKS. The chemical-dynamical error covariances are critical to reduce the wind error in the model analysis state particularly through the ozone-wind covariances effective in the upper-troposphere lower-stratosphere region. Additional tests with strongly-biased initial forecasts, within a stratospheric sudden warming experiment, confirm the ability of the EnKF to efficiently propagate information from ozone observations to the dynamical model state.L'assimilation d'ensemble utilise une méthode de Monte-Carlo pour estimer les covariances d'erreur du moment qui permettent le transfert d'information des variables observées aux variables corrélées à celles-ci. Puisque les vents sont très peu observés dans la stratosphère et que les modèles y présentent des biais, la possibilité de contraindre l'état dynamique du modèle par l'assimilation d'observations de température et d'ozone par la technique d'ensemble est tentée. L'applicabilité de l'assimilation d'ensemble dans un système chimique/dynamique couplé est testé lors d'une expérience idéalisé (modèle parfait) de simulation de système d'observation avec le modèle de chimie-climat IGCM-FASTOC. La localisation des covariances est indispensable à la stabilité du système d'assimilation avec filtre de Kalman d'ensemble (EnKF) et les paramètres optimaux offrent une forte contrainte sur l'état dynamique global du modèle lorsque l'on assimile des observations satellites synthétiques de température et d'ozone stratosphériques uniquement. Le couplage entre l'ozone, la température et les vents est étudié dans le système EnKF optimisé. Les observations de température et d'ozone stratosphériques créent des incréments dynamiques bénéfiques lors des phases d'analyses. Il y a également une rétroaction lors de la phase de prédiction du système d'assimilation de données, qui aide à contraindre davantage les états chimiques et dynamiques globaux. L'impact potentiel de l'assimilation de données postérieures au temps d'analyse en mode multivarié est estimé avec un lisseur d'ensemble de Kalman (EnKS). L'assimilation d'observations additionnelles asynchrones, ayant jusqu'à 48 heures d'écart avec le temps d'analyse, offre des améliorations aux analyses de l'EnKF presque équivalentes à celles obtenues par assimilation d'une quantité égale d'observations additionnelles synchrones. L'EnKS présente des impacts bénéfiques sur l'état d'analyse des variables non observées mais des impacts mitigés sur l'état analysé des variables observées. La capacité de contraindre les vents stratosphériques non-observés grâce à l'assimilation d'observations d'ozone est démontrée dans le système d'assimilation d'ensemble avec l'EnKF et l'EnKS. Les covariances d'erreurs chimiques- dynamiques sont essentielles à la réduction de l'erreur de vents dans l'état analysé du modèle, en particulier les covariances ozone-vent qui font effet dans la haute troposphère et basse stratosphère. Des expériences additionelles avec un état initial fortement biaisé, en l'occurence un réchauffement stratosphérique soudain, confirment l'abilité de l'EnKF à transférer de façon efficace l'information depuis les observations d'ozone vers l'état dynamique du modèle.
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Stewart, Laura M. "Correlated observation errors in data assimilation." Thesis, University of Reading, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553080.
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Data assimilation techniques combine observations and prior model forecasts to create initial conditions for numerical weather prediction (NWP). The relative weighting as- signed to each observation in the analysis is determined by the error associated with its measurement. Remote sensing data often have correlated errors, but the correlations are typically ignored in NWP. As operational centres move towards high-resolution fore- casting, the assumption of uncorrelated errors becomes impractical. This thesis provides new evidence that including observation error correlations in data assimilation schemes is both feasible and beneficial. We study the dual problem of quantifying and modelling observation error correlation structure. Firstly, in original work using statistics from the Met Office 4D- Var assimilation system, we diagnose strong cross-channel error eo- variances for the IASI satellite instrument. We then see how in a 3D- Var framework, information content is degraded under the assumption of uncorrelated errors, while re- tention of an approximate correlation gives clear benefits. These novel results motivate further study. We conclude by modelling observation error correlation structure in the framework of a one-dimensional shallow water model. Using an incremental 4D- Var assimilation system we observe that analysis errors are smallest when correlated error covariance matrix approximations are used over diagonal approximations. The new re- sults reinforce earlier conclusions on the benefits of including some error correlation structure.
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Moodey, Alexander J. F. "Instability and regularization for data assimilation." Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.602412.
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The process of blending observations and numerical models is called in the environmental sciences community, data assimilation. Data assimilation schemes produce an analysis state, which is the best estimate to the state of the system. Error in the analysis state, which is due to errors in the observations and numerical models, is called the analysis error. In this thesis we formulate an expression for the analysis error as the data assimilation procedure is cycled in time and derive results on the boundedness of the analysis error for a number of different data assimilation schemes. Our work is focused on infinite dimensional dynamical systems where the equation which we solve is ill-posed. We present stability results for diagonal dynamical systems for a three-dimensional variational data assimilation scheme. We show that increasing the assumed uncertainty in the background state, which is an a priori estimate to the state of the system, leads to a bounded analysis error. We demonstrate for general linear dynamical systems that if there is uniform dissipation in the model dynamics with respect to the observation operator, then regularization can be used to ensure stability of many cycled data assimilation schemes. Under certain conditions we show that cycled data assimilation schemes that update the background error covariance in a general way remain stable for all time and demonstrate that many of these conditions hold for the Kalman filter. Our results are extended to dynamical system where the model dynamics are nonlinear and the observation operator is linear. Under certain Lipschitz continuous and dissipativity assumptions we demonstrate that the assumed uncertainty in the background state can be increased to ensure stability of cycled data assimilation schemes that update the background error covariance. The results are demonstrated numerically using the two-dimensional Eady model and the Lorenz 1963 model.
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Luo, Xiaodong. "Recursive bayesian filters for data assimilation." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509987.
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Lung, Shiu-cheung, and 龍兆章. "Assimilation of phytate-phosphorus by plants." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B35710986.
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Fowler, Alison M. "Assimilation of misplaced boundary layer features." Thesis, University of Reading, 2010. http://centaur.reading.ac.uk/24800/.
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Ades, Melanie. "Data assimilation in highly nonlinear sytems." Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603528.
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Particle filters are a class of data-assimilation schemes which, unlike current operational data-assimilation methods, make no assumptions about the linearity of the model equations or observation operators. This means They can potentially represent the full, possibly multi-modal, posterior probability density function (pdf). Unfortunately, the standard Sequential Importance Resampling (SIR) particle filter requires too many pal1icles to make it a viable operational data-assimilation scheme in high dimensional systems. This thesis explores an adaptation to the SIR filter, the equivalent-weights particle filter, designed to ensure an ensemble representation of the high probability region of the posterior pdf even in high dimensional systems. The formulation of the equivalent-weights particle filter involves various tuneable parameters. The first part of this thesis focusses on a theoretical and practical examination of the effect of the parameter choices on the ability of the equivalent-weights particle filter to represent the posterior pdf. Theoretically, the importance of ensuring equivalent weights for the majority of particles is shown and consequently the need to sample from a mixture proposal density al analysis time. Practically, the potentially large influence of the parameters is demonstrated and how this can be used to establish appropriate choices for some of the parameters is discussed. The second part of the thesis considers two areas related to the potential of the equivalent-weights particle filter as a viable data-assimilation scheme: the capacity to represent the posterior pdf and the effect on any model balances that may be present in the system. The ability of the equivalent-weights particle filter to represent the high probability region of the posterior pdf with relatively few particles in high dimensional systems is demonstrated. Changes in the observation distribution, frequency or error statistics result in minimal impact to this posterior representation. More distinctive effects are seen when the model error statistics are misrepresented in the ensemble. The final section on model balances relates to the use of the equivalent-weights pa11icle filter in atmosphere and ocean numerical models. The equivalent-weights par1icle filter is shown to have little effect on the model balances present in a simple ocean model and hence there is no evidence for the introduction of spurious gravity waves
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McLeod, Paul. "The melting and assimilation of xenoliths." Thesis, University of Bristol, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336850.
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Jenkins, Siân. "Numerical model error in data assimilation." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.665395.
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In this thesis, we produce a rigorous and quantitative analysis of the errors introduced by finite difference schemes into strong constraint 4D-Variational (4D-Var) data assimilation. Strong constraint 4D-Var data assimilation is a method that solves a particular kind of inverse problem; given a set of observations and a numerical model for a physical system together with a priori information on the initial condition, estimate an improved initial condition for the numerical model, known as the analysis vector. This method has many forms of error affecting the accuracy of the analysis vector, and is derived under the assumption that the numerical model is perfect, when in reality this is not true. Therefore it is important to assess whether this assumption is realistic and if not, how the method should be modified to account for model error. Here we analyse how the errors introduced by finite difference schemes used as the numerical model, affect the accuracy of the analysis vector. Initially the 1D linear advection equation is considered as our physical system. All forms of error, other than those introduced by finite difference schemes, are initially removed. The error introduced by `representative schemes' is considered in terms of numerical dissipation and numerical dispersion. A spectral approach is successfully implemented to analyse the impact on the analysis vector, examining the effects on unresolvable wavenumber components and the l2-norm of the error. Subsequently, a similar also successful analysis is conducted when observation errors are re-introduced to the problem. We then explore how the results can be extended to weak constraint 4D-Var. The 2D linear advection equation is then considered as our physical system, demonstrating how the results from the 1D problem extend to 2D. The linearised shallow water equations extend the problem further, highlighting the difficulties associated with analysing a coupled system of PDEs.
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Hammarström, Ylva. "Folkhemmets parias : Debatten om romernas assimilation." Thesis, Mittuniversitetet, Institutionen för humaniora, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-19586.
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