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1

Lee, Jennifer Elizabeth. "Alien species and propagules in the Antarctic : movements through space and time." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/4508.

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Thesis (PhD (Botany and Zoology))--University of Stellenbosch, 2009.<br>ENGLISH ABSTRACT: Although the impacts of biological invasions are widely appreciated, a bias exists in research effort to post‐dispersal processes because of the difficulties of measuring propagule pressure and the detecting of newly established species. Here the Antarctic is used as a model system in which to quantify the initial dispersal of alien species and investigate the factors that contribute to the establishment and range dynamics of alien species once they have arrived in the region. Human movements are known to transport alien species into the Antarctic, some of which have successfully established and had wide ranging consequences in recipient ecosystems. Considering terrestrial flora, this research found that over 700 seeds from 99 taxa, including some species known to be invasive, are transported into the Antarctic each year in association with South African National Antarctic Programme (SANAP) passenger luggage and cargo. The first ever assessment of propagule drop‐off indicated that 30‐50% of these propagules will enter the recipient environment. Further results suggested that the construction of the British Antarctic Survey Halley VI station will facilitate the transport of over 5000 seeds from 34 taxa into the region, making this a significant pathway for introductions. Propagule pressure due to SANAP logistics is also considerable for marine species. Fouling assemblages on the external hull surfaces of the SANAP resupply vessel, the SA Agulhas, form only once the vessel’s anti‐fouling paint has been damaged by travel through sea ice and are characterised by low diversity. Ice scour prevents fouling assemblages from being transported to the Antarctic continent, but assemblages remain largely intact when travelling to sub‐Antarctic Islands. In the sea‐chests of the vessel populations of a known invasive, Mytilus galloprovincialis, were found with some individuals having survived transportation to the Antarctic region on multiple occasions. Once species have overcome initial dispersal barriers, they face further ecological and physiological challenges in order to establish in the recipient region. The parasitoid wasp Aphidius matricariae was first recorded on Marion Island in 2001. Surveys around the island show that adult abundance and the frequency of aphid parasitism are highest adjacent to a common anchor point of the SA Agulhas and decline away from this region. Genetic diversity was low, suggesting that the population was established from a single introduction. This highlights that high propagule pressure is not necessary for successful establishment of introduced invertebrates. Another species that has overcome the dispersal barrier is the terrestrial slug Deroceras panormitanum, which was introduced to Marion Island in the 1970’s and has since spread throughout much of the coastal habitat of the island. For this species range limits are set by intolerance of low temperature and salinity, and abundance structure is characterized by patches and gaps which are associated with this species inability to tolerate dry conditions. To prevent further alien introductions in the region, targeted management of high risk pathways is required. In addition, increased vigilance is needed to detect and manage newly established aliens before their ranges expand.<br>AFRIKAANSE OPSOMMING: Alhoewel die impak van biologiese indringings in die breë waardeer word, bestaan daar vooroordeel in navorsingspogings ten opsigte van na‐verspreidingsprosesse, weens die moeilikhede om verspreidingseenheid druk te meet en in die opsporing van nuut gevestigde spesies. Hier word die Antarktiese streek as ‘n model sisteem gebruik waarin die aanvanklike verspreiding van uitheemse spesies gekwantifiseer kan word en om die faktore wat bydrae tot die vestiging en grens dinamika van uitheemse spesies te ondersoek, wanneer hulle in ’n streek aangekom het. Menslike bewegings is bekend daarvoor om uitheemse spesies na die Antarktiek te vervoer, sommige waarvan suksesvol gevestig het en omvattende gevolge in die ontvanger ekosisteme gehad het. Aangaande terrestriële flora het hierdie navorsing gevind dat oor die 700 sade van 99 taxa, insluitende sommige spesies wat bekend is om indringend te wees, jaarliks na die Antarktiek vervoer word in assosiasie met die Suid Afrikaanse Nasionale Antarktiese Program (SANAP) se bagasie en vrag. Die eerste waardebepaling van verspreidingseenheid afgooi het aangedui dat 30‐50% van hierdie verspreidingseenhede die ontvanger omgewing sal binnedring. Verdere resultate het voorgestel dat die konstruksie van die Britse Antarktiese Opname Halley VI stasie die vervoer van 5000 sade van 34 taxa sal fasiliteer die streek in, wat dit ’n betekenisvolle weg maak vir indringings. Verspreidingseenheid druk is ook, as gevolg van die SANAP logistiek, aanmerklik vir mariene spesies. Vuilgoed versamelings op die eksterne omhullende oppervlaktes van die SANAP her‐voorsieningsvaartuig, die SA Agulhas, vorm wanneer die vaartuig se anti‐vuilgoed verf beskadig is met reis deur see‐ys en word gekenmerk deur lae diversiteit. Ys skuring voorkom dat vuilgoed versamelings vervoer word na die Antarktiese kontinent, maar versamelings bly grootliks vasgeheg wanneer na sub‐Antarktiese eilande gereis word. Populasies van ’n welbekende indringer, Mytilus galloprovincialis, is gevind in die see‐storingsarea van die vaartuig, met sommige individue wat die vervoering na die Antarktiese streek oorleef het op verskeie geleenthede. Wanneer spesies die aanvanklike verspreidingshindernisse oorkom het, staar hulle verdere ekologies en fisiologiese uitdagings in die gesig ten einde in die ontvanger streek te vestig. Die parasitiese wespe Aphidius matricariae is vir die eerste keer op Marion aangeteken in 2001. Opnames om die eiland toon dat volwasse oorvloed en die frekwensie van plantluis parasitisme die hoogste is aangrensend die algemene ankerpunt van die SA Agulhas en afneem weg van die omgewing af. Genetiese diversiteit was laag, wat voorstel dat die populasie gevestig het van ’n enkele bekendstelling. Dit lig uit dat hoë verspreidingseenheid druk nie nodig is vir die suksesvolle vestiging van bekendgestelde invertebrata nie. ‘n Ander spesie wat die verspreidingshindernisse oorkom het is die landslak Deroceras panormitanum wat in die 1970’s op Marion Eiland bekendgestel is en wat sedertdien versprei het oor meeste van die kushabitat van die eiland. Vir hierdie spesie word grens limiete vasgestel deur onverdraagsaamheid vir lae temperature en saliniteit en die oorvloedstruktuur word gekenmerk deur laslappe en gapings wat geassosieer word met die spesie se onvermoë om droë kondisies te hanteer. Om verdere uitheemse bekendstellings in die streek te voorkom, word geteikende bestuur van hoë risiko weë vereis. Toenemende waaksamheid is bykomend nodig vir die opsporing en bestuur van nuutgevestigde uitheemse spesies voordat hulle grense verbreed.
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2

Chu, Cheuk-hung Sid. "The implications of spatial and social structures for time patterns of pedestrian movements in urban streets." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36749357.

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3

Estay, Huidobro Rodrigo Andrés. "Seismic parameters of space - time clustered mining - induced aftershock sequences applied to seismic hazard in mining." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/168513.

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Tesis para optar al grado de Doctor en Ingeniería de Minas<br>Una característica común en la minería que se realiza en roca competetente es la sismicidad inducida. Esta es resultado de los cambios en los esfuerzos y el fallamiento de la roca alrededor de las excavaciones mineras. Posterior a un evento sísmico, existe un aumento en los niveles de sismicidad que gradualmente decaen con el tiempo, conocido como una secuencia de réplicas. Restringir el acceso a las áreas de la mina por el tiempo suficiente que permita que ocurra este decaimiento de los eventos sísmicos es el enfoque principal de los protocolos de re entrada. Las propiedades estadísticas de las secuencias de réplicas pueden ser estudiadas mediante tres relaciones o leyes sísmicas: (1) Ley de Gutenberg Richter, (2) Ley de Omori Modificada (MOL) para el decaimiento temporal de la sismicidad, y (3) Ley de Båth para la magnitud de la réplica de mayor magnitud. Esta tesis contiene tres partes principales: estimación y correlaciones de los parámetros de las leyes sísmicas para secuencias de réplicas inducidas por la minería, desarrollo de protocolos de re entrada en el espacio tiempo magnitud y el reconocimiento y comportamiento temporal de secuencias de réplicas usando un aglomeramiento espacio tiempo. En la primera parte, se aplicaron las tres leyes sísmicas, además del modelo estocástico de Reasenberg Jones, para estudiar los parámetros de 11 secuencias sísmicas inducidas por la minería en cuatro minas en Ontario, Canadá. Para proporcionar directrices para el desarrollo del protocolo de re entrada, se estudió y aplicó la dependencia de esto parámetros con la magnitud del evento sísmico principal de la secuencia sísmica. Los resultados obtenidos son coincidentes con los que diferentes autores han estimado en sismicidad tectónica. Sin embargo, aparecen algunas "diferencias de escala", especialmente con el valor b de Gutenberg Richter y el valor p de la ley modificada de Omori, encontrando que, en promedio, hay diferencias de +0.35 y -0.2 respectivamente entre los resultados de la sismicidad inducida y tectónica. La segunda parte corresponde al desarrollo de un protocolo estocástico de re entrada en el espacio tiempo magnitud, utilizando las relaciones entre los parámetros sísmicos inducidos y la magnitud del evento principal. Se define un radio de exclusión y una relación entre el tiempo de máxima curvatura y la magnitud del evento principal. Esto permite construir curvas de decaimiento sísmico, proporcionando información sobre los patrones de decaimiento de una secuencia en curso. Finalmente, se propone un rango de probabilidad de ocurrencia de la réplica de mayor magnitud, basado en el modelo de probabilidad de Reasenberg Jones. La última parte consiste en analizar el comportamiento del agrupamiento de la sismicidad inducida por la minería a través del tiempo y el espacio. Usando el criterio estadístico de Akaike para seleccionar los parámetros del aglomeramiento espacio tiempo, fue posible identificar una secuencia de réplicas asociada a un evento principal con magnitud Mw = 0.7. Además, se encontró que la distancia espacio tiempo aparentemente disminuye su valor antes de que ocurra un evento principal, para luego retornar a su valor normal. Todos los hallazgos anteriores proporcionan una aproximación a pautas concisas y bien justificadas para el desarrollo del protocolo de re entrada.
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4

Chu, Cheuk-hung Sid, and 朱卓雄. "The implications of spatial and social structures for time patterns ofpedestrian movements in urban streets." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37920844.

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5

Paulionienė, Laura. "Statistical modelling of spatio-temporal data based on spatial interpolation of time series parameters." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2013~D_20140117_113114-31261.

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Space – time data modeling problem is analysed. Often spatial data sets are relatively small, and the points, where observations are taken, are located irregularly. When solving spatial task, usually we are interpolating or estimating the spatial average. Time series data usually are used to predict future values. Meanwhile, the space - time tasks combines both types of tasks. Few original modeling methods of spatial time series are proposed. The proposed methods firstly analyzes the univariate time series, and after removing temporal dependence, spatial dependence in the time series of residuals is measured. Aim of this dissertational work - to create time series model at new unobserved location by incorporating spatial interaction thru spatial interpolation of estimated time series parameters. Such a model is based on the spatial interpolation of time series parameters.<br>Disertaciniame darbe nagrinėjama erdvės – laiko duomenų modeliavimo problema. Dažnai erdvinių duomenų rinkiniai yra gana nedideli, o taškai, kuriuose pasklidę stebėjimai, išsidėstę netaisyklingai. Sprendžiant „erdvinį“ uždavinį, paprastai siekiama inerpoliuoti arba įvertinti erdvinį vidurkį. Laiko eilučių duomenys dažniausiai naudojami ateities reikšmėms prognozuoti. Tuo tarpu erdvės – laiko uždaviniai jungia abu uždavinių tipus. Pasiūlyta keletas originalių erdvinių laiko eilučių modeliavimo metodų. Siūlomi metodai pirmiausia analizuoja vienmates laiko eilutes, o pašalinus laikinę priklausomybė jose, laiko eilučių liekanoms vertinama erdvinė priklausomybė. Tikslas – sudaryti modelį, leidžiantį prognozuoti požymio reikšmę naujame, nestebėtame taške, nauju laiko momentu. Tokio modelio sudarymas remiasi laiko eilučių parametrų erdviniu interpoliavimu.
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6

Brooks, Jr Raymond Matthew. "Developing a methodology for the assessment of freedom of movement: the influence of spatial parameters on movement and space use in mice (Mus musculus)." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8896.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2008.<br>Thesis research directed by: Dept. of Animal and Avian Sciences. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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7

Awater, Holger. "Perception of visual space at the time of saccadic eye movements Wahrnehmung des visuellen Raumes im Zeitraum sakkadischer Augenbewegungen /." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965503003.

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8

Monteiro, Giselle Antunes. "Generalized linear differential equations in a Banach space: continuous dependence on parameters and applications." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/55/55135/tde-30032012-105214/.

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The purpose of this work is to investigate continuous dependence on parameters for generalized linear differential equations in a Banach space- valued setting. More precisely, we establish a theorem inspired by the clas- sical continuous dependence result due to Z. Opial. In addition, our second outcome extends, to Banach spaces, the result proved by M. Ashordia in the framework of finite dimensional generalized linear differential equations. Roughly speaking, the continuous dependence derives from assumptions of uniform convergence of the functions in the right-hand side of the equations, together with the uniform boundedness of variation of the linear terms. Fur- thermore, applications of these results to dynamic equations on time scales and also to functional differential equations are proposed. Besides these results on continuous dependence, we complete the theory of abstract Kurzweil-Stieltjes integration so that it is well applicable for our purposes in generalized linear differential equations. In view of this, our contributions are related not only to differential equations but also to the abstract Kurzweil-Stieltjes integration theory itself. The new results presented in this work are contained in the papers [26] and [27], both accepted for publication<br>O objetivo deste trabalho é investigar a dependência contínua de soluções em relação a parâmetros para equações diferenciais lineares generalizadas no contexto de espaços de Banach. Mais precisamente, apresentamos um teo- rema inspirado no resultado clássico de dependência contínua obtido por Z. Opial. Nosso segundo resultado estende, para espaços de Banach, o provado por M. Ashordia no contexto de equações diferenciais lineares gen- eralizadas em dimensão finita. Em linhas gerais, a dependência contínua decorre da convergência uniforme das funções à direita das equações, junta- mente com a limitação uniforme da variação dos termos lineares. No mais, são propostas aplicações desses resultados em equações dinâmicas em escalas temporais e também em equações diferenciais funcionais. Além dos resultados em dependência contínua, completamos à teoria de integração abstrata de Kurzweil-Stieltjes de modo que esta se adeque aos nossos propósitos em equações diferenciais lineares generalizadas. Assim, nossas contribuições dizem respeito não apenas a equações diferenciais, mas também a teoria de integração abstrata de Kurzweil-Stieltjes em si. Os resultados originais apresentados neste trabalho estão contidos nos artigos [26] e [27], ambos aceitos para publicação
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Ojha, Nirmal [Verfasser], and Axel W. [Akademischer Betreuer] Drescher. "A new tool for predicting distribution patterns of African dragonflies in space and time: sensitivity analyses of model parameters and environmental variables." Freiburg : Universität, 2015. http://d-nb.info/1122742606/34.

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10

Cheparukhina, Anna. "Ověření biologických parametrů člověka pro robotickou vizuální teleprezenci." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221324.

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This work presents a research in the field of robotic visual telepresence. At the beginning explains the principle of teleprezence and it makes classification of robots according to their properties and concepts. Furthermore, there is a review of modern existing robots. The following chapter discusses the human visual system, the basic parameters and functions including parameters of head movements. Subsequently have been selected critical parameters for visual telepresence. At the conclusion of the theoretical part were designed some experiments to validation of human body biological parameters. In the practical part was conducted measuring the extent and speed of head movements, eye distinction depending on the lighting and measurement of visual field man. Also, a series of experiments was performed for practical technical embodiment of the telepresence system rescue robot for class Orpheus.
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Davídek, Daniel. "Systém pro pokročilou vizuální teleprezenci." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221115.

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The introduction of this document presents some basic principles of visual telepresence with analysis of important aspects of the design. Afterwards there is a brief ovrewview of some of the applications of telepresence systems. Subsequently there is a description of the basic parameters and functions of the human visual perception system including the head motion parameters. This document examines the creation of telepresence apparatus through which is the user able to percieve visual stimuli accross distance. The device consist of camera with wide FOV positioned on the last link of the servo-motor chain with 3 DOF. Camera view is projected into scene in position read from actual motor posture. The scene is perceived through the HMD Oculus Rift (DK1, DK2) where the actual head-orientation read from the HMD inertial sensors is the entered end value for the rotation angles of the servomotors. A \csharp (WPF) program was developed for the controling and setting of motors which handles the byte communication through RS485-USB converter and also configures and starts the telepresence mode. The telepresence scene is drawn with help of SharpDX and SharpOVR - the \csharp wrappers of DirectX and LibOVR.
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Yamanaka, Fábio Norio Razé. "Inclusão do efeito da frequência nas equações de estado de linhas bifásicas : análise no domínio do tempo /." Ilha Solteira : [s.n.], 2009. http://hdl.handle.net/11449/87126.

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Orientador: Sérgio Kurokawa<br>Banca: Afonso José do Prado<br>Banca: Lourenço Matias<br>Resumo: O objetivo deste projeto é o desenvolvimento de um modelo de linha de transmissão bifásica diretamente no domínio do tempo, que leve em consideração o efeito da freqüência sobre seus parâmetros longitudinais, utilizando os conceitos de variáveis de estado. Os parâmetros longitudinais, variáveis em relação à freqüência, serão aproximados por funções racionais, cujos pólos e resíduos deverão ser determinados por meio do algoritmo vector fitting. Em seguida, as funções racionais que descrevem o comportamento dos parâmetros longitudinais serão associadas com um circuito elétrico equivalente, que será inserido em cada um dos circuitos π, constituindo uma grande quantidade de cascata de circuitos π. O modelo será utilizado para a realização de simulações de transitórios resultantes das operações de manobras e chaveamentos que ocorrem em uma linha bifásica com plano de simetria vertical. Os resultados serão comparados com os resultados obtidos com programas computacionais do tipo EMTP (cascata de circuitos π inserida no EMTP). Ao término do projeto teremos a nossa disposição um modelo de linha de transmissão que não necessita do uso de simuladores do tipo EMTP.<br>Abstract: The objective of this work is to implement a computational model of two-phase transmission line in time domain taking into account its frequency dependent longitudinal parameters. The line is represented through a cascade of π circuits and the frequency dependence of the longitudinal parameters is approximated by a rational functions that can be associated with an equivalent circuit representation and this equivalent circuit is inserted in each π circuit. After that the cascade is described through state equations. Validating the model, a frequency dependent two-phase line is represented by a cascade of π circuits. The model will be use for typical switching transients in a two-phase transmission line with a vertical symmetrical plan. The simulations were carried out using state space techniques and an EMTP program (in this case, the cascade was inserted in the EMTP program). It is observed that the simulation results obtained with state space representation are in agreement with those results obtained with EMTP.<br>Mestre
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Yamanaka, Fábio Norio Razé [UNESP]. "Inclusão do efeito da frequência nas equações de estado de linhas bifásicas: análise no domínio do tempo." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/87126.

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Made available in DSpace on 2014-06-11T19:22:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-09Bitstream added on 2014-06-13T19:08:07Z : No. of bitstreams: 1 yamanaka_fnr_me_ilha.pdf: 596127 bytes, checksum: 6456b9483b4e3ac56e9f1fded745845f (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>O objetivo deste projeto é o desenvolvimento de um modelo de linha de transmissão bifásica diretamente no domínio do tempo, que leve em consideração o efeito da freqüência sobre seus parâmetros longitudinais, utilizando os conceitos de variáveis de estado. Os parâmetros longitudinais, variáveis em relação à freqüência, serão aproximados por funções racionais, cujos pólos e resíduos deverão ser determinados por meio do algoritmo vector fitting. Em seguida, as funções racionais que descrevem o comportamento dos parâmetros longitudinais serão associadas com um circuito elétrico equivalente, que será inserido em cada um dos circuitos π, constituindo uma grande quantidade de cascata de circuitos π. O modelo será utilizado para a realização de simulações de transitórios resultantes das operações de manobras e chaveamentos que ocorrem em uma linha bifásica com plano de simetria vertical. Os resultados serão comparados com os resultados obtidos com programas computacionais do tipo EMTP (cascata de circuitos π inserida no EMTP). Ao término do projeto teremos a nossa disposição um modelo de linha de transmissão que não necessita do uso de simuladores do tipo EMTP.<br>The objective of this work is to implement a computational model of two-phase transmission line in time domain taking into account its frequency dependent longitudinal parameters. The line is represented through a cascade of π circuits and the frequency dependence of the longitudinal parameters is approximated by a rational functions that can be associated with an equivalent circuit representation and this equivalent circuit is inserted in each π circuit. After that the cascade is described through state equations. Validating the model, a frequency dependent two-phase line is represented by a cascade of π circuits. The model will be use for typical switching transients in a two-phase transmission line with a vertical symmetrical plan. The simulations were carried out using state space techniques and an EMTP program (in this case, the cascade was inserted in the EMTP program). It is observed that the simulation results obtained with state space representation are in agreement with those results obtained with EMTP.
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Ahn, Song-ee. "Ur kurs : Utbytesstudenters rörelser i tid och rum." Doctoral thesis, Linköpings universitet, Institutionen för beteendevetenskap och lärande, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10356.

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The aim of this dissertation is to study exchange students’ movement and exchange studies as a trajectory in time and space. The dissertation is based on interviews with fourteen Korean exchange students at Swedish universities. The theoretical framework is based on Actor–Network Theory (ANT). ANT argues that everything that does something is an actor (human and non-human) and that an actor cannot be separated from a network that acts through the actor. ANT also argues that one’s location is not explained only in terms of Euclidean space and time but also in terms of spatiality and temporality, which are a network’s production. The dissertation shows that the students were enrolled and mobilized in the exchange programs by heterogeneous actors and that there were specific network spaces that produced exchange students at the home universities. The exchange students were excluded at the Swedish host universities by being formally included without direction. At the host universities, they went off course from their educational trajectories because the curriculum disappeared during their exchange studies. The dissertation also shows that the exchange students were enrolled and mobilized in the networks of “international students” at the host universities. Theses exchange students instead moved in the same way as the other exchange students, which stabilized the networks of “international students” at the host universities. It describes how the exchange students acted at a distance as actor of networks in Korea. When they returned, many of them had to prolong their educational period. This was a result of the translation of exchange studies at the home universities. In this dissertation, it shows that the exchange program was performed not only by individual exchange students; rather, it was performed in the associations of heterogeneous actors.<br>Syftet med avhandlingen är att undersöka utbytesstudenters rörelser och utbytesstudier som banor i tid och rum. Avhandlingen baseras på intervjuer med fjorton koreanska utbytesstudenter som vistats på olika svenska värduniversitet. Den teoretiska referensramen grundar sig i Actor-Network Theory (ANT). ANT argumenterar för att allt som gör något är en aktör, oavsett om den är mänsklig eller icke-mänsklig. En aktör kan inte urskiljas från nätverket vilken agerar genom aktören. Aktörens lokalisering kan inte enbart förklaras i termer av det euklidiska rummet och tiden, utan också i termer av rumslighet och tolkningar av tidsförloppen vilka är nätverksprodukter. Avhandlingen visar att studenterna enrollerades och mobiliserades till utbytesprogrammen av heterogena aktörer och att det fanns specifika rum där utbytesstudenterna skapades. På värduniversiteten exkluderades de genom att formellt inkluderas i olika kurser utan att dessa ofta hade någon riktning i deras studier. Utbytesstudenternas studier kom ur kurs jämfört med deras ordinarie utbildningar eftersom en läroplan saknades på värduniversiteten. Avhandlingen visar att utbytesstudenterna enrollerades och mobiliserades in i nätverk av de internationella studenterna på värduniversiteten. Utbytesstudenterna rörde sig på samma sätt som andra utbytesstudenter, vilket stabiliserade nätverken av ”internationella studenter” på värduniversiteten. I avhandlingen beskrivs även utbytesstudenternas fortsatta agerande som aktörer i nätverken i Korea. När de återvänt till Korea behövde de flesta förlänga sin utbildningstid och detta var ett resultat av hur utbytesperioden tillgodoräknades på hemuniversiteten. Det var ett resultat av översättningen i utbytesprogrammen på hemuniversiteten. Avhandlingen visar att utbytesprogrammen inte enbart genomfördes av de individuella utbytesstudenterna; snarare genomfördes de i förbindelser med heterogena (mänskliga och icke-mänskliga) aktörer.
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15

Papež, Milan. "Monte Carlo identifikační strategie pro stavové modely." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400416.

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Stavové modely jsou neobyčejně užitečné v mnoha inženýrských a vědeckých oblastech. Jejich atraktivita vychází především z toho faktu, že poskytují obecný nástroj pro popis široké škály dynamických systémů reálného světa. Nicméně, z důvodu jejich obecnosti, přidružené úlohy inference parametrů a stavů jsou ve většině praktických situacích nepoddajné. Tato dizertační práce uvažuje dvě zvláště důležité třídy nelineárních a ne-Gaussovských stavových modelů: podmíněně konjugované stavové modely a Markovsky přepínající nelineární modely. Hlavní rys těchto modelů spočívá v tom, že---navzdory jejich nepoddajnosti---obsahují poddajnou podstrukturu. Nepoddajná část požaduje abychom využily aproximační techniky. Monte Carlo výpočetní metody představují teoreticky a prakticky dobře etablovaný nástroj pro řešení tohoto problému. Výhoda těchto modelů spočívá v tom, že poddajná část může být využita pro zvýšení efektivity Monte Carlo metod tím, že se uchýlíme k Rao-Blackwellizaci. Konkrétně, tato doktorská práce navrhuje dva Rao-Blackwellizované částicové filtry pro identifikaci buďto statických anebo časově proměnných parametrů v podmíněně konjugovaných stavových modelech. Kromě toho, tato práce adoptuje nedávnou particle Markov chain Monte Carlo metodologii pro návrh Rao-Blackwellizovaných částicových Gibbsových jader pro vyhlazování stavů v Markovsky přepínajících nelineárních modelech. Tyto jádra jsou posléze použity pro inferenci parametrů metodou maximální věrohodnosti v uvažovaných modelech. Výsledné experimenty demonstrují, že navržené algoritmy překonávají příbuzné techniky ve smyslu přesnosti odhadu a výpočetního času.
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Sebastianutti, Marco. "Geodesic motion and Raychaudhuri equations." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18755/.

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The work presented in this thesis is devoted to the study of geodesic motion in the context of General Relativity. The motion of a single test particle is governed by the geodesic equations of the given space-time, nevertheless one can be interested in the collective behavior of a family (congruence) of test particles, whose dynamics is controlled by the Raychaudhuri equations. In this thesis, both the aspects have been considered, with great interest in the latter issue. Geometric quantities appear in these evolution equations, therefore, it goes without saying that the features of a given space-time must necessarily arise. In this way, through the study of these quantities, one is able to analyze the given space-time. In the first part of this dissertation, we study the relation between geodesic motion and gravity. In fact, the geodesic equations are a useful tool for detecting a gravitational field. While, in the second part, after the derivation of Raychaudhuri equations, we focus on their applications to cosmology. Using these equations, as we mentioned above, one can show how geometric quantities linked to the given space-time, like expansion, shear and twist parameters govern the focusing or de-focusing of geodesic congruences. Physical requirements on matter stress-energy (i.e., positivity of energy density in any frame of reference), lead to the various energy conditions, which must hold, at least in a classical context. Therefore, under these suitable conditions, the focusing of a geodesics "bundle", in the FLRW metric, bring us to the idea of an initial (big bang) singularity in the model of a homogeneous isotropic universe. The geodesic focusing theorem derived from both, the Raychaudhuri equations and the energy conditions acts as an important tool in understanding the Hawking-Penrose singularity theorems.
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17

Samardzija-Grek, Tatjana. "Propositions relatives narratives en Français." Paris 3, 2008. http://www.theses.fr/2008PA030047.

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La thèse propose l’analyse morphosyntaxique et textuelle des propositions relatives dites « narratives » dans le cadre de la sémantique du prototype. Est définie comme narrative une proposition relative qui, postposée au prédicat d’accueil, a pour but d’exprimer, au premier plan, le procès VR, causé par le procès de la proposition d’accueil (VA) moyennant la participation de l’entité ANT+REL. La proposition relative narrative forme, avec sa proposition d’accueil, une séquence relative narrative. L’interprétation narrative prototypique d’une relative est la résultante des valeurs-paramètres opposées à celles caractérisant une proposition relative caractérisante, ces valeurs tenant surtout du prédicat verbal, prototypiquement « perfectif », « spécifiant », « transitif ». Ces propriétés des prédicats dans la séquence relative narrative rejoignent le double lien anaphorique et syntaxique du bloc relatif formé par l’antécédent et le relatif pour créer une unique image de progression des évènements dans le temps et dans l’espace, appelé « effet de dominos ». Grâce aux rapports sémantique et syntaxique entre l’antécédent et le relatif, de même qu’aux propriétés morphosyntaxiques des procès VA et VR, la proposition relative narrative dispose d’un sémantisme unique par rapport à d’autres structures narratives, telles les temporelles ou les coordonnées. Une première conséquence en est l’expression de causalité, renforcée par la progression thématique linéaire, ou ANT thème devient REL thème. Cette structure montre comment, par un usage systématique des valeurs périphériques d’une structure, il est possible d’en créer un type tout différent<br>The thesis proposes both morphosyntaxical and textual analyses of the so-called « narrative » relative clauses from the point of view of the standard version of prototype theory. One may consider as narrative any relative clause postponed to the predicate of the embedding clause (VA), which aims at narrating a figure event (VR) presented as caused by VA trough the participation, direct or indirect, of the ANT+REL entity. The interpretation of all narrative relatives depends upon a certain number of parameters, each organised in a form of value continuum. The prototype of a narrative relative clause is the sum of parameter values opposite to the prototype of a relative clause in general. The narrative relatives refer to parameters pertaining to verbal values such as “perfective”, specifying” or “transitive”. Typically appearing in narrative contexts, the narrative relative clauses grant some particular meanings to the narrated events. Whereas coordination tends to be a mere statement of events and states, and while temporal clauses insist on a temporal succession of events, the narrative relative clauses picture both temporal succession of events and their progression in space. Temporal progression is the result of insisting on the perfective verb aspect and on the postposition of the relative predicate. Spatial progression depends upon the anaphoric relation between the antecedent and the relative pronoun. This causes a strong causal relation between VA and VR. Such structure of the narrative relative sequence equals to the linear thematic progression, where a comment becomes the topic of the next clause
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18

Vestin, Albin, and Gustav Strandberg. "Evaluation of Target Tracking Using Multiple Sensors and Non-Causal Algorithms." Thesis, Linköpings universitet, Reglerteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-160020.

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Today, the main research field for the automotive industry is to find solutions for active safety. In order to perceive the surrounding environment, tracking nearby traffic objects plays an important role. Validation of the tracking performance is often done in staged traffic scenarios, where additional sensors, mounted on the vehicles, are used to obtain their true positions and velocities. The difficulty of evaluating the tracking performance complicates its development. An alternative approach studied in this thesis, is to record sequences and use non-causal algorithms, such as smoothing, instead of filtering to estimate the true target states. With this method, validation data for online, causal, target tracking algorithms can be obtained for all traffic scenarios without the need of extra sensors. We investigate how non-causal algorithms affects the target tracking performance using multiple sensors and dynamic models of different complexity. This is done to evaluate real-time methods against estimates obtained from non-causal filtering. Two different measurement units, a monocular camera and a LIDAR sensor, and two dynamic models are evaluated and compared using both causal and non-causal methods. The system is tested in two single object scenarios where ground truth is available and in three multi object scenarios without ground truth. Results from the two single object scenarios shows that tracking using only a monocular camera performs poorly since it is unable to measure the distance to objects. Here, a complementary LIDAR sensor improves the tracking performance significantly. The dynamic models are shown to have a small impact on the tracking performance, while the non-causal application gives a distinct improvement when tracking objects at large distances. Since the sequence can be reversed, the non-causal estimates are propagated from more certain states when the target is closer to the ego vehicle. For multiple object tracking, we find that correct associations between measurements and tracks are crucial for improving the tracking performance with non-causal algorithms.
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19

Stewart, Emma Elizabeth Marshall. "A journey through time and space: the spatiotemporal profile of attention relative to saccade and reach." Thesis, 2016. http://hdl.handle.net/2440/105357.

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In an interactive environment, we use a multitude of eye and hand movements to gather information about our surroundings, and to act upon what we see. While these are the eventual, overt behaviours that we observe, there are countless hidden neural processes guiding where we move our eyes and hands. This thesis will examine one such of these processes: visual attention. Visual attention has been shown to produce perceptual benefits, such as an increase in contrast sensitivity, at the attended location, and there is evidence that before an eye or hand movement is made, attention shifts to the location of that upcoming movement target. This thesis aimed to comprehensively map the spatiotemporal profile of attention when reaches and saccades were being planned and executed, in order to compare how attention shifts when different types of movements are being made. The first experiment mapped the spatiotemporal profile of attention relative to a reach alone. Results of this study showed that when a reach alone is being planned, there is a broad spatial allocation of attention across the visual field, while the temporal profile shows a slight increase before the onset of a reach, with a dramatic drop in performance once the hand is in flight. The second experiment compared the spatiotemporal profile of attention for saccades alone, and saccades with a concurrent reach. These results, in contrast showed a large increase in performance before the start of a movement, and a plateau of performance during the movement itself. The third experiment aimed to explore how attention may differ depending on where a probed location is situated relative to the direction of a movement, and to compare how this may change across different movement effectors. Results showed that the profile of attention differed depending on both movement effector and whether the probe appeared in line with or orthogonal to the direction of a movement. These results also suggest that attention spreads differently when a saccade is being made, irrespective of whether a reach is being conducted or not. Overall, the results of this thesis showed three main effects: the spatiotemporal profile of attention is different when a saccade is being made compared to a reach alone; attentional facilitation at the location of a probe is different depending on where the probe is located, relative to the direction of movement; and this profile of attention varies depending on the type of movement being enacted. Additional results also suggest that attention may act in a dual facilitatory/inhibitory manner, depending on the movement effector. Taken together, these results provide evidence that different types of movement planning may require different levels of attentional guidance, and also provide evidence that pre-movement attention may be a flexibly allocated resource, depending on the demands of the task, and the movements being enacted.<br>Thesis (Ph.D.) -- University of Adelaide, School of Psycholoy, 2016.
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20

Awater, Holger [Verfasser]. "Perception of visual space at the time of saccadic eye movements = Wahrnehmung des visuellen Raumes im Zeitraum sakkadischer Augenbewegungen / vorgelegt von Holger Awater." 2002. http://d-nb.info/965503003/34.

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21

Poon, Aubrey. "Three Applications of Time-Varying Parameter and Stochastic Volatility Models to the Malaysian and Australian Economy." Phd thesis, 2017. http://hdl.handle.net/1885/118728.

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After the introductory chapter, this thesis comprises of three chapters that examines the application of time-varying parameter and stochastic volatility models to the Malaysian and Australian economy. Chapter 2 aims to determine whether the propagation and transmission mechanism of Malaysian monetary policy differed during the Asian Financial Crisis of 1997/98 and the Global Financial Crisis of 2007/08. The methodology employs a time-varying vector-autoregression framework. The primary result is that despite having no evidence of time-variation in the propagation mechanism of Malaysian monetary policy the average contribution of a monetary policy shock to the variability of each macroeconomic variable-Real GDP, Inflation and the Nominal Effective Exchange Rate-differs between the two crises. This finding suggests that despite the propagation mechanism being relatively constant, Malaysia's monetary policy transmission mechanism evolves over time. We believe that the main mechanism driving this evolution is the time-variation in the variance-covariance matrix of the shocks of the model, not the coefficients. We also find some evidence that the implementation of capital controls reduced the influenceability of monetary policy on the Malaysian economy. Chapter 3 investigates whether incorporating time variation and fat-tails into a suite of popular univariate and multivariate Gaussian distributed models can improve the forecast performance of key Australian macroeconomic variables: real GDP growth, CPI inflation and a short-term interest rate. The forecast period is from 1992Q1 to 2014Q4, thus replicating the central banks forecasting responsibilities since adopting inflation targeting. We show that time varying parameters and stochastic volatility with Student's-t error distribution are important modeling features of the data. More specifically, a vector autoregression with the proposed features provides the best interest and inflation forecasts over the entire sample. Remarkably, the full sample results show that a simple rolling window autoregressive model with Student's-t errors provides the most accurate GDP forecasts. Chapter 4 estimates a time-varying parameter Panel Bayesian vector autoregression with a new feature: a common stochastic volatility factor in the error structure, to assess the synchronicity and the nature of Australian State business cycles. The common stochastic volatility factor reveals that macroeconomic volatility or uncertainty was more pronounced during the Asian Financial Crisis as compared to the more recent Global Financial Crisis. Next, the Panel VAR’s common, regional and variable specific indicators capture several interesting economic facts. In the first instance, the fluctuations of the common indicator closely follow the trend line of the Organisation for Economic Co-operation and Development composite leading indicators for Australia making it a good proxy for nationwide business cycle fluctuations. Next, despite significant co-movements of Australian States and Territory business cycles during times of economic contractions, the regional indicators suggest that the average degree of synchronisation across the Australian States and Territories cycles in the 2000s is only half of that presented in the 1990s. Given that aggregate macroeconomic activity is determined by cumulative activity of each of the nation states, the results suggests that the Federal Government should award state governments greater autonomy in handling state specific cyclical fluctuations.
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22

Minto, Cóilín. "Ecological Inference from Variable Recruitment Data." 2011. http://hdl.handle.net/10222/13881.

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To understand the processes affecting the abundance of wild populations is a fundamental goal of ecology and a prerequisite for the management of living resources. Variable abundance, however, makes the investigation of ecological processes challenging. Recruitment, the process whereby new individuals enter a given stage of a ?sh population, is a highly variable entity. I have confronted this issue by developing methodologies speci?cally designed to account for, and ecologically interpret, patterns of variability in recruitment. To provide the necessary context, Chapter 2 begins with a review of the history of recruitment science. I focus on the major achievements as well as present limitations, particularly regarding environmental drivers. Approaches that include explicit environmental information are contrasted with time-varying parameter techniques. In Chapter 3, I ask what patterns of variability in pre-recruit survival can tell us about the strength of density-dependent mortality. I provide methods to investigate the presence of density-dependent mortality where this has previously been hindered by highly variable data. Stochastic density-independent variability is found to be attenuated via density dependence. Sources of recruitment variability are further partitioned in Chapter 4. Using time-varying parameter techniques, signi?cant temporal variation in the annual reproductive rate is found to have occurred in many Atlantic cod populations. Multivariate state space models suggest that populations in close proximity typically have a shared response to environmental change whereas marked differences occur across latitude. Hypotheses that could result in consistent changes in productivity of cod populations are tested in Chapter 5. I focus on a meta-analytical investigation of potential interactions between Atlantic cod and small pelagic species, testing aspects of the cultivation-depensation hypothesis. The ?ndings suggest that predation or competition by herring and mackerel on egg and larval cod could delay recovery of depleted cod populations. Chapter 6 concludes with a critical re?ection on: the suitability of the theories employed, the underlying assumptions of the empirical approaches, and the quality of the data used in my thesis. Application of ecological insights to ?sheries management is critically evaluated. I then propose future work on recruitment processes based on methods presented herein.
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Themeẞl, Nathalie. "Asteroseismic inferences from red-giant stars." Doctoral thesis, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E5F1-E.

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