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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.
191

Adverb placement : an optimality theoretic approach

Engels, Eva January 2004 (has links)
Adverb positioning is guided by syntactic, semantic, and pragmatic considerations and is subject to cross-linguistic as well as language-specific variation. The goal of the thesis is to identify the factors that determine adverb placement in general (Part I) as well as in constructions in which the adverb's sister constituent is deprived of its phonetic material by movement or ellipsis (gap constructions, Part II) and to provide an Optimality Theoretic approach to the contrasts in the effects of these factors on the distribution of adverbs in English, French, and German. <br><br> In Optimality Theory (Prince & Smolensky 1993), grammaticality is defined as optimal satisfaction of a hierarchy of violable constraints: for a given input, a set of output candidates are produced out of which that candidate is selected as grammatical output which optimally satisfies the constraint hierarchy. Since grammaticality crucially relies on the hierarchic relations of the constraints, cross-linguistic variation can be traced back to differences in the language-specific constraint rankings. Part I shows how diverse phenomena of adverb placement can be captured by corresponding constraints and their relative rankings: <br><br> - contrasts in the linearization of adverbs and verbs/auxiliaries in English and French<br> - verb placement in German and the filling of the prefield position<br> - placement of focus-sensitive adverbs<br> - fronting of topical arguments and adverbs<br><br> Part II extends the analysis to a particular phenomenon of adverb positioning: the avoidance of adverb attachment to a phonetically empty constituent (gap). English and French are similar in that the acceptability of pre-gap adverb placement depends on the type of adverb, its scope, and the syntactic construction (English: wh-movement vs. topicalization / VP Fronting / VP Ellipsis, inverted vs. non-inverted clauses; French: CLLD vs. Cleft, simple vs. periphrastic tense). Yet, the two languages differ in which strategies a specific type of adverb may pursue to escape placement in front of a certain type of gap. In contrast to English and French, placement of an adverb in front of a gap never gives rise to ungrammaticality in German. Rather, word ordering has to obey the syntactic, semantic, and pragmatic principles discussed in Part I; whether or not it results in adverb attachment to a phonetically empty constituent seems to be irrelevant: though constraints are active in every language, the emergence of a visible effect of their requirements in a given language depends on their relative ranking. The complex interaction of the diverse factors as well as their divergent effects on adverb placement in the various languages are accounted for by the universal constraints and their language-specific hierarchic relations in the OT framework. / Die Positionierung von Adverbien wird von syntaktischen, semantischen und pragmatischen Erwägungen geleitet; sie unterliegt der zwischen-sprachlichen als auch der einzel-sprachlichen Variation. Ziel der Arbeit ist es, diejenigen Faktoren zu identifizieren, die ausschlaggebend sind für die Platzierung von Adverbien im allgemeinen (Teil I) sowie in speziellen Konstruktionen, in denen die Schwesterkonstituente eines Adverbs aufgrund von Bewegung oder Ellipse kein phonetisches Material enthält (Gap-Konstruktionen, Teil II). Des weiteren sollen die unterschiedlichen Ausprägungen dieser Faktoren in den distributionalen Mustern des Englischen, Französischen und Deutschen in einem optimalitätstheoretischen Rahmen erklärt werden. <br><br> In der Optimalitätstheorie (Prince & Smolensky 1993) ist Grammatikalität als optimale Erfüllung einer Hierarchie von verletzbaren Constraints definiert: Für einen gegebenen Input wird eine Menge von Outputkandidaten bereitgestellt, aus der derjenige Kandidat als grammatischer Output gewählt wird, der die Constrainthierarchie am besten erfüllt. Da die hierarchischen Relationen der Constraints für die Ermittlung des grammatischen Outputs entscheidend sind, kann zwischen-sprachliche Variation auf Diskrepanzen in den einzel-sprachlichen Constrainthierarchien zurückgeführt werden. Der erste Teil der Arbeit zeigt, wie diverse Phänomene der Adverbstellung mit entsprechenden Constraints und ihren Anordnungen erfasst werden können: <br><br> - Kontraste in der Linearisierung von Adverbien und Verben/Auxiliaren im Englischen und Französischen<br> - Verbplatzierung im Deutschen und Vorfeldbesetzung<br> - Platzierung von fokus-sensitiven Adverbien<br> - Voranstellung von topikalen Argumenten und Adverbien <br><br> Der zweite Teil der Arbeit spezialisiert sich auf ein bestimmtes Phänomen der Adverbpositionierung: das Meiden der Adverb-Adjunktion an eine phonetisch leere Konstituente (Gap). Englisch und Französisch ähneln sich insofern, als die Akzeptabilität der Adverbpositionierung vor einem Gap beeinflusst wird vom Typ des Adverbs, seinem Skopus und der syntaktischen Konstruktion (Englisch: wh-Bewegung vs. Topikalisierung / VP Voranstellung / VP Ellipse, invertierte vs. nicht-invertierte Sätze; Französisch: CLLD vs. Cleft, einfache vs. periphrastische Tempusformen). Die beiden Sprachen unterscheiden sich jedoch darin, ob - und falls ja - welche Strategie ein bestimmter Typ von Adverb verfolgen kann, um der Stellung vor einem speziellen Gap zu entkommen. Im Gegensatz zum Englischen und Französischen führt die Stellung eines Adverbs vor einem Gap im Deutschen nie zu Ungrammatikalität. Vielmehr hat die Adverbpositionierung den in Teil I diskutierten syntaktischen, semantischen und pragmatischen Prinzipien zu gehorchen; ob dies in der Adjunktion eines Adverbs an eine phonetisch leere Konstituente resultiert, scheint dabei irrelevant: Obwohl Constraints in jeder Sprache aktiv sind, hängt es von ihrer relativen Anordnung zueinander ab, ob sie einen sichtbaren Effekt in einer gegebenen Sprache hinterlassen. Die komplexe Interaktion der diversen Faktoren sowie deren divergierende Ausprägung auf die Adverbplatzierung in den unterschiedlichen Sprachen können in der Optimalitätstheorie auf die universalen Constraints und deren einzel-sprachliche Anordnung zurückgeführt werden.
192

Effective Sampling Design for Groundwater Transport Models

Nordqvist, Rune January 2001 (has links)
Model reliability is important when groundwater models are used for evaluation of environmental impact and water resource management. Model attributes such as geohydrologic units and parameter values need to be quantified in order to obtain reliable results. A primary objective of sampling design for groundwater models is to increase the reliability of modelling results by selecting effective measurement locations and times. It is advantageous to employ simulation models to guide measurement strategies already in early investigation stages. Normally, optimal design is only possible when model attributes are known prior to constructing a design. This is not a meaningful requirement as the model attributes are the final result of the analysis and are not known beforehand. Thus, robust design methods are required that are effective for ranges of parameter values, measurement error types and for alternative conceptual models. Parameter sensitivity is the fundamental model property that is used in this thesis to create effective designs. For conceptual model uncertainty, large-scale sensitivity analysis is used to devise networks that capture sufficient information to determine which model best describes the system with a minimum of measurement points. In fixed conceptual models, effective parameter- and error-robust designs are based on criteria that minimise the size of the parameter covariance matrix (D-optimality). Optimal designs do not necessarily have observations with the highest parameter sensitivities because D-optimality reduces parameter estimation errors by balancing high sensitivity and low correlation between parameters. Ignoring correlation in sparse designs may result in considerably inefficient designs. Different measurement error assumptions may also give widely different optimal designs. Early stage design often involves simple homogenous models for which the design effectiveness may be seriously offset by significant aquifer heterogeneity. Simple automatic and manual methods are possible for design generation. While none of these guarantee globally optimal designs, they do generate designs that are more effective than those normally used for measurement programs. Effective designs are seldom intuitively obvious, indicating that this methodology is quite useful. A general benefit of this type of analysis, in addition to the actual generation of designs, is insight into the relative importance of model attributes and their relation to different measurement strategies.
193

Some Properties of Exchange Design Algorithms Under Correlation

Stehlik, Milan January 2006 (has links) (PDF)
In this paper we discuss an algorithm for the construction of D-optimal experimental designs for the parameters in a regression model when the errors have a correlation structure. We show that design points can collapse under the presence of some covariance structures and a so called nugget can be employed in a natural way. We also show that the information of equidistant design on covariance parameter is increasing with the number of design points under exponential variogram, however these designs are not D-optimal. Also in higher dimensions the exponential structure without nugget leads to collapsing of the D-optimal design when also parameters of covariance structure are of interest. However, if only trend parameters are of interest, the designs covering uniformly the whole design space are very efficient. For illustration some numerical examples are also included. (author's abstract) / Series: Research Report Series / Department of Statistics and Mathematics
194

Content-aware Caching and Traffic Management in Content Distribution Networks

Amble, Meghana Mukund 2010 December 1900 (has links)
The rapid increase of content delivery over the Internet has lead to the proliferation of content distribution networks (CDNs). Management of CDNs requires algorithms for request routing, content placement, and eviction in such a way that user delays are small. Our objective in this work is to design feasible algorithms that solve this trio of problems. We abstract the system of front-end source nodes and back-end caches of the CDN in the likeness of the input and output nodes of a switch. In this model, queues of requests for different pieces of content build up at the source nodes, which route these requests to a cache that contains the content. For each request that is routed to a cache, a corresponding data file is transmitted back to the source across links of finite capacity. Caches are of finite size, and the content of the caches can be refreshed periodically. A requested but missing item is fetched to the cache from the media vault of the CDN. In case of a lack of adequate space at the cache, an existing, unrequested item may be evicted from the cache in order to accommodate a new item. Every such cache refresh or media vault access incurs a finite cost. Hence the refresh periodicity allowed to the system represents our system cost. In order to obtain small user delays, our algorithms must consider the lengths of the request queues that build up at the nodes. Stable policies ensure the finiteness of the request queues, while good polices also lead to short queue lengths. We first design a throughput-optimal algorithm that solves the routing-placement eviction problem using instantaneous system state information. The design yields insight into the impact of different cache refresh and eviction policies on queue length. We use this and construct throughput optimal algorithms that engender short queue lengths. We then propose a regime of algorithms which remedies the inherent problem of wastage of capacity. We also develop heuristic variants, and we study their performance. We illustrate the potential of our approach and validate all our claims and results through simulations on different CDN topologies.
195

Second Order Sufficient Optimality Conditions for Nonlinear Parabolic Control Problems with State Constraints

Raymond, Jean-Pierre, Tröltzsch, Fredi 30 October 1998 (has links) (PDF)
In this paper, optimal control problems for semilinear parabolic equations with distributed and boundary controls are considered. Pointwise constraints on the control and on the state are given. Main emphasis is laid on the discussion of second order sufficient optimality conditions. Sufficiency for local optimality is verified under different assumptions imposed on the dimension of the domain and on the smoothness of the given data.
196

The acquisition of English articles by Mandarin-speaking learners: an optimality-theoretic syntax account

Hu, Yuxiu, Lucille., 胡玉秀. January 2011 (has links)
published_or_final_version / Linguistics / Doctoral / Doctor of Philosophy
197

Poetic organization and poetic license in the lyrics of Hank Williams, Sr. and Snoop Dogg

Horn, Elizabeth Alena 24 January 2011 (has links)
This dissertation addresses the way a linguistic grammar can yield to poetic organization in a poetic text. To this end, two corpora are studied: the sung lyrics of country music singer Hank Williams, Sr. and the rapped lyrics of gansgta rap artist Snoop Dogg. Following a review of relevant literature, an account of the poetic grammar for each corpus is provided, including the manifestation of musical meter and grouping in the linguistic text, the reflection of metrical grouping in systematic rhyme, and rhyme fellow correspondence. In the Williams corpus, final cadences pattern much as in the English folk verse studied in Hayes and MacEachern (1998), but differ in that there are more, and therefore more degrees of saliency. Rhyme patterns reflect grouping structure and correlate to patterns in final cadences, and imperfect rhyme is limited to phonologically similar codas. In the Snoop Dogg corpus syllables do not always align with the metrical grid, metrical mapping and rhyme patterning often challenge grouping structure, and imperfect rhyme is more diverse, as has been shown to be the case for contemporary rap generally (Krims 2000, Katz 2008). Following Rice (1997), Golston (1998), Reindl and Franks (2001), Michael (2003), and Fitzgerald (2003, 2007), meter, grouping and rhyme are modeled as driving phonological, morphological and syntactic deviation in Optimality Theoretic terms. In the Hank Williams corpus, metrical mapping and grouping constraints are shown to drive a number of linguistically deviatory phenomena including stress shift, syllabic variation and allomorphy, while rhyme patterning constraints govern syntactic inversion. In the Snoop Dogg corpus, rhyme fellow correspondence and rhyme patterning constraints play a more significant role, driving enjambment, syllabic variation, and allomorphy. Some linguistically deviatory phenomena derive from ordinary language variation, e.g. (flawr)~(flaw.[schwa]r), and some do not, e.g. syllable insertion in insista. The latter is more common in the Snoop Dogg corpus. / text
198

Prisitaikančiosios baigtinių elementų strategijos plokštuminiams tamprumo teorijos uždaviniams / Adaptive finite element strategies for solution of two dimensional elasticity problems

Vasiliauskienė, Lina 22 June 2006 (has links)
The advent of modern computer technologies provided a powerful tool in numerical simulations. One of the most frequently used method for the discretization of the physical domain is Finite element Method (FEM). One of the main problems in a finite element analysis is the adequacy of the finite element mesh. Since the quality of the finite element solution directly depends on the quality of meshes, the additional process to improve the quality of meshes is necessary for reliable finite element approximation. In order to perform quality-assessed numerical simulation, the adaptive finite element strategies have been developed. These strategies integrate the finite element analysis with error estimation and fully automatic mesh modification, user interaction with this process is limited by initial geometry data and possible error tolerance definition. The finite element solution, obtained during adaptive finite element strategy process, approximates quite good different engineering structures. Despite many works in this area the problem of the adequate finite element mesh is not fully solved and additional developments are needed in order to improve adaptive mesh refinement strategy process. The aim and tasks of the work – to obtain methodology for quality assessed discretization to finite elements for complex geometry engineering structures by adaptive finite element strategies. To realize this purpose the following scientific tasks have been dealt: to develop an automatic... [to full text]
199

Prisitaikančiosios baigtinių elementų strategijos plokštuminiams tamprumo teorijos uždaviniams / Adaptive finite element strategies for solution of two dimensional elasticity problems

Vasiliauskienė, Lina 23 June 2006 (has links)
The advent of modern computer technologies provided a powerful tool in numerical simulations. One of the most frequently used method for the discretization of the physical domain is Finite element Method (FEM). One of the main problems in a finite element analysis is the adequacy of the finite element mesh. Since the quality of the finite element solution directly depends on the quality of meshes, the additional process to improve the quality of meshes is necessary for reliable finite element approximation. In order to perform quality-assessed numerical simulation, the adaptive finite element strategies have been developed. These strategies integrate the finite element analysis with error estimation and fully automatic mesh modification, user interaction with this process is limited by initial geometry data and possible error tolerance definition. The finite element solution, obtained during adaptive finite element strategy process, approximates quite good different engineering structures. Despite many works in this area the problem of the adequate finite element mesh is not fully solved and additional developments are needed in order to improve adaptive mesh refinement strategy process. The aim and tasks of the work – to obtain methodology for quality assessed discretization to finite elements for complex geometry engineering structures by adaptive finite element strategies. To realize this purpose the following scientific tasks have been dealt: to develop an automatic... [to full text]
200

從借字看漢語聲調與英語輕重音的對應 / Stress-to-tone adaptation in Chinese loanwords: an optimality theory perspective

王麗婷, Wang, Li Ting Unknown Date (has links)
在有關漢語聲調與英語輕重音的借字研究中,英語重音與漢語聲調的對應並不一致,因此,本篇研究分別從語料庫與優選理論的觀點,重新檢驗漢語借字中漢語聲調與英語輕重音的關係。觀察語料庫發現英語重音傾向與包含高音 (high pitch) 的聲調對應,因此本文提ANCHOR-L(H,σ) 和ANCHOR-R(H, σ) 制約,分別要求英語重音節的H音高要固定在對應音節聲調的左端或右端。在*[+voiced]/[+H]- 和 *[-voiced]/[-H]- 的制約下,輸出值呈現voice enhancement的效果。換句話說,*[+voiced]/[+H]- 制約要求含有聲聲母之英語重音節與低起始音域的聲調對應;*[-voiced]/[-H]- 制約要求含無聲聲母之英語重音節與高起始音域的聲調對應。含有聲聲母之英語重音節可能對應到高平調或中升調,制約層級的改變能預測之。若ANCHOR-L(H,σ)與ANCHOR-R(H,σ)支配*[+voiced]/[+H]- ,則高平調被選出,但是,若 *[+voiced]/[+H]- 支配ANCHOR-L(H,σ) 與 ANCHOR-R(H,σ),則中升調被選出。在RELCORR制約的要求下,對應重音節聲調的左端調值不低於對應輕音節聲調的左端調值。 / The studies of Mandarin loanwords adapted from English have suggested different tonal preferences in correspondence to English stress. This thesis reexamines the relationship between stress and tone in the English-to-Mandarin loanwords based on a corpus and the Optimality Theory. Two anchoring constraints, ANCHOR-L(H,σ) and ANCHOR-R(H,σ) are proposed to require the realization of the pitch accent H of the English stressed syllables, indicating the fact that English stress prefers a tone with a high pitch. The *[+voiced]/[+H]- and *[-voiced]/[-H]- constraints show a pattern of voice enhancement. *[+voiced]/[+H]- requires an English stressed syllable with a voiced onset to be adapted with an initially low-registered tone; *[-voiced]/[-H]- requires an English stressed syllable with a voiceless onset to be adapted with an initially high-registered tone. In addition, constraint re-ranking predicts the alternatively choices between the H-tone and the MH-tone for an English stressed syllable with a voiced onset. The H-tone is selected if ANCHOR-L(H,σ)and ANCHOR-R(H,σ) outrank *[+voiced]/[+H]-; whereas the MH-tone is chosen if *[+voiced]/[+H]- dominates these two anchoring constraints. The RELCORR constraint requires a left-edge tonal correspondence, where the left-edge pitch of a tone that corresponds to an English stressed syllable is not lower than one that corresponds to an English unstressed syllable.

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