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1
Wilson, Sarah Kate. "Durational painting : gifting, grafting, hosting, collaborating." Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/18875/.
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This thesis takes as its focus contemporary painting, and develops an understanding of painting as a time-based medium. My research project addresses the array of strategies artists employ to produce durational paintings, a term I have coined as a means of referring to paintings that destabilise the traditional idea of painting as a static object, hung on a wall. The medium of painting embraces other mediums, such as performance and installation, to yield durational paintings. These paintings engage people in their production: vitally, they are participatory and are produced through collaboration. Furthermore, these paintings employ materials imbued with particular properties, such as longevity or, conversely, ephemerality. In time-based media collections and in existing histories of participatory and relational practices painting is absent: these omissions are redressed by the present study. Now that painting is time-based, it is ‘live’.
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Caulfield, Anne Jeanette. "In search of isochrony : compensating for durational warping in speech production." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24587.
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The rhythmic organization of speech into regular intervals (i.e. isochrony), is a strong perceptual phenomenon. However, Investigators have been unable to demonstrate the existence of isochrony in production data. It is hypothesized in this study that the intended rhythm of a speaker is in fact isochronous, but that this is obscured by several distorting influences which introduce durational irregularity at the syllable level, e.g. intrinsic duration, stress, position of the syllable in a phrase and number of syllables in a phrase. It is proposed that removing the predictable durational irregularities will yield a more regular signal, reflecting the (hypothesized) Intended Isochronous rhythm of the speaker. The latter two sources of distortion introduce progressive durational irregularity or "warping" which can be readily incorporated into an automated "dewarplng" procedure. A computer program was devised to compensate, at the syllable level for these two sources of distortion. The former two sources are not amenable to such an automated procedure, and were therefore not included. The "dewarping" program was run on the speech amplitude envelopes of two speakers, one French and one English.
The results indicate that, for the French speaker, dewarping does remove some of the durational Irregularity, yielding a more regular amplitude envelope. For the English speaker, no such Improvement in regularity is obtained. This indicates that the dewarping used, which presumes the syllable as "unit" of dewarping, is appropriate for syllable-timed languages such as French, but inappropriate for stress-timed languages such as English. It therefore provides some support for isochrony in French at the syllable level. Finally, the results also give support to the hypothesis that the degree of warping perceived as regular in speech perception studies corresponds to the degree of dewarping which, conversely, yields the most regular speech amplitude envelope; however, further experimentation is necessary to determine the optimum values of the parameters of the dewarping function.Medicine, Faculty of
Audiology and Speech Sciences, School of
Graduate
3
Al-Khatib, Saleh. "Variation in speech timing : a durational model for modern standard Arabic." Thesis, Lancaster University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333464.
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Goldberg, Stephen Gregory. "Durational Control of Defensive Burying in Rats: An Investigation of a Species-Specific Defense Reaction." DigitalCommons@USU, 1988. https://digitalcommons.usu.edu/etd/5977.
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Six experiments were run to determine whether the duration of conditioned defensive burying (COB) in rats is a function of its consequences.
Four experiments developed the methodology. Experiment 1 replicated the standard one-trial experiment, where rats are shocked once by a prod. All three rats exhibited CDB. Experiment 2 used a lever-press-for-water contingency to force recontact with the lever, following shock deliveries in Sessions 6 and 14. All three rats buried the lever in both sessions. Experiment 3 replicated Experiment 2, employing albino and hooded rats. All six buried the lever. The albinos exhibited longer burying durations. Experiment 4 used the lever-press-for-water contingency but employed extinction to test whether rats would bury the lever under that condition. They did not.
Experiment 5 used three groups of rats to determine whether burying durations are a function of CDB's consequences. Groups LS and LSH had enough sawdust to cover the lever, but a hole under the lever was opened during LSH's burying. Group SS lacked enough sawdust to cover the lever. The groups' mean burying durations (MBDs) were not significantly different in Session 6. Following Session 14, group differences and a group-by-session interaction were statistically significant. Effect sizes for Groups LS and SS were large. Group LS's MBD increased, Group LSH's remained unchanged, and Group SS's decreased.
Experiment 6 used two groups of rats to determine whether MBDs are a function of shock source visibility. Group C's substratum consisted of uncolored, transparent Plexiglas blocks. Group B had black, opaque blocks. Only the group-by-session interaction was statistically significant. The MBDs of Groups Band C paralleled those of Groups LS and SS in Experiment 5. The effect sizes for C and B were large and medium, respectively.
CDB occurred in all experiments where the rats received shocks, and CDB was reproduced in experiments where the animals were forced to recontact the shock source through a lever-press-for-water contingency.
CDB durations are a function of their consequences. Rats whose burying covers or blocks the shock source from view exhibit longer burying durations in succeeding shock trials. Rats whose burying is ineffective exhibit shorter durations.
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Coogan, Amanda. "Deconstructing and re-constructing instances of live durational performance art : yellow-re-performed." Thesis, Ulster University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.633031.
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Live durational performance art practice is the site of investigation for this research project. The event of another human presented for intentional viewing in somatic, non-verbal practice is explored through a phenomenologicallense. The research examines underlying issues by firstly addressing "the cult of personality" in works where the artist is performer and then exploring individual involvement in live performance from both the performer's and audience member's perspectives. This thesis thus examines live durational performance under four categories: Site, Time, Performer and Audience. The research is both a textual and a practical one, with many of the artworks scrutinized stemming from my own work. The practice of an artist as performer is dissected and re-built through a re-performance project; Yellow-Re-pelTormed. This reperformance project is analysed and contextualized within the recently emerged debate surrounding re-performance strategies in performance art practice belonging to visual art. The proposition of re-performance is correlated to appropriation art, with both challenging the status of an original artwork. Through the experience of selected live artworks produced for this research, this study illuminates the complexities and difficulties inherent in this unstable practice. By analysing live performance from an insider's perspective, this thesis contributes to the understanding of the practice of durationallive performance in a gallery context. Interrelating reperformance and appropriation art, the thesis seeks further to demystify the art form and critically proposes re-performance as a strategy of remembering and also for making new live performance art. Through documenting and reflecting on the processes of commissioning and exhibiting performances, as well as briefing re-performers and eliciting inthe- moment responses from participants on all sides, this project can inform future practices and debates. It is my view that it can help gallerybased live performance to be better understood in relation to presence, and the experience of presence in re-performance.
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Kromholz, Sophie C. "The artwork is not present : an investigation into the durational engagement with temporary artworks." Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/7716/.
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This thesis presents a conceptual knot, namely of how to sustain the intentionally temporary. Part of the original contribution of this thesis lies in exploring what it means for an artwork to be temporary, tracing the historical context from the twentieth century onwards, thereby establishing the category of temporary artworks, and providing thoughts on how to care for temporary artworks so that they might be known and experienced by future audiences. On the basis of this research, a practical proposal is developed for what a retrospective of temporary artworks might look like. Temporary artworks should be considered as a category unto their own because of the specific set of constraints which set them apart: they are physical works of art which exist for an intentionally limited amount of time, and are created only once. These specific constraints problematize the engagement of future audiences due to the works’ very limited and singular existence as a physical work. In order to address the issue of how to (re)visit impermanence, I develop the claim that what is passed on from a temporary artwork is contingent on the stakeholders, including the primary audience, who are posited as a group of unintentional archivists holding stock in a type of living archive. After their material unmaking, temporary artworks can be experienced through the notion that ‘the artwork is not present’, a riff on artist Marina Abramović’s retrospective work The Artist is Present (2010). A retrospective of temporary artworks would consist of memories and documents contextualizing their fragmentary nature, highlighting what Severin Fowles discusses as ‘the carnality of absence’. A clarification of what is missing assists in sustaining what I develop and describe as ‘the performance of loss’, a critical part of temporary artworks. Stewarding a temporary artwork into the future thus depends on letting the material object go, and contextualizing its presence, loss, and absence for future audiences.
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Holm, Snefrid. "Intonational and durational contributions to the perception of foreign-accented Norwegian : An experimental phonetic investigation." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for språk- og kommunikasjonsstudier, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2331.
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Young, Shikika Sade. "The Durational Effects of a Free Operant Condition on Automatically Maintained Stereotypic Behavior and Discrete Trial Task Responding." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5806.
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This study examined the effects of three fixed-duration free operant access conditions on rates of automatically maintained stereotypic behavior and correct task responding during discrete trial training (DTT) with two children diagnosed with autism. Following a functional analysis, confirming automatic function, interviews/observations were conducted to identify behavioral indicators of satiation and an average satiation level. In this endeavor, participants were exposed to a free operant condition to validate satiation of stereotypic responding. Once satiation level was averaged, two durational conditions were computed: Long (75% access) and Short (25% access). A third condition, Deprivation, involved blocking all attempts at the stereotypic response for the average duration till satiation. An alternating treatment design was used to examine the effects of these three conditions on stereotypy and correct responding during subsequent discrete trial tasks. For both, participants correct responding did not seem to be affected by the length of the pre-session access to the stereotypic behavior prior to the DTT session. For Marcus, the Long condition may have acted as an abolishing operation (AO) during DTT. Following the Short condition he engaged in higher rates of the stereotypic behaviors during his DTT sessions compared to the other conditions. For the Sara, it appears that pre-session access to stereotypy had little effect on stereotypic behavior during DTT sessions.
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Rissanen, J. (Janne). "A perceptual study of difficulties met by native speakers of English in the production of the durational patterns of Finnish disyllabic word structures." Master's thesis, University of Oulu, 2014. http://urn.fi/URN:NBN:fi:oulu-201410041921.
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This thesis presents a perceptual study of difficulties met by native speakers of English in the production of the durational patterns of Finnish disyllabic word structures. The primary purpose of the analysis was to investigate how a message changes on the way from text to utterance and further from utterance to perception, and then to evaluate how well the informants have managed in their utterances on the basis of the listeners’ perceptions. The test material of 70 words contains words pairs consisting of meaningful disyllabic Finnish words and pseudowords in random order. The meaningful words were selected so that an expected quantitative deviation would form a minimal pair with an alternative that they can be mixed with. The words were read by nine informants in a noiseless speech lab, their productions were recorded, and the recordings were played to groups of upper secondary school students, whose task was to write down their immediate perceptions. The perception data amounting to 14,350 samples was inserted to a tailored relational database for analysis. The perception analysis was made from two main points of view, focusing on quantitative changes in different syllable patterns and on the individual tendencies of the informants, including some notions of qualitative characteristics as well. The findings were, when necessary, supported by results derived from segmental phonetic measurements. All quantitative deviation types, which in this disyllabic material are shortening and lengthening of the vowel in both syllable positions and that of consonants on both sides of the syllable boundary, were analysed from the original words in each syllable pattern. By far the most common and the most persistent deviation type is shortening of the vowel in the second syllable. Problems are typically faced with patterns that contain both short and long sound segments, especially those containing a consonant cluster at the syllable boundary. Words with evenly long, either short or long sound segments are the easiest ones to master. Shortening of the vowel in the first syllable is the next most common occurrence. Durational problems at the syllable boundary, the most common being the double-length consonant perceived as short, are a challenging group altogether. These changes are typically coupled so that on the basis of the perceptions, simultaneous shortening and lengthening of the sound sequences occur on both sides of the syllable boundary, resulting in perceptions that are perhaps furthest away from the intended utterance and thus hard to understand. The study underlines the importance of mastering the quantitative opposition in Finnish from the viewpoint of successful communication. On the basis of the findings of this study training material for those learning Finnish as a second language could be tailored to better serve the needs of native English speakersTässä pro gradu -tutkielmassa esitellään havaintoaineistoon perustuva tutkimus vaikeuksista, joita englanninkieliset suomenoppijat kohtaavat pyrkiessään tuottamaan rakenteeltaan suomen kielen mukaisia kaksitavuisia sanoja. Analyysin päätarkoitus oli selvittää, kuinka viesti muuttuu matkalla tekstistä lausumaksi ja lausumasta havainnoksi, ja sen jälkeen arvioida äidinkielenään suomea puhuvien kuuntelijoiden havaintojen perusteella, kuinka hyvin informantit onnistuivat tuotoksissaan. 70 sanan testiaineisto koostuu sanapareista, joissa on oikeita kaksitavuisia suomen kielen sanoja ja rakenteeltaan samanlaisia hölynpölysanoja satunnaisessa järjestyksessä. Merkitykselliset sanat laadittiin siten, että ennustettava kvantiteetin poikkeama tuottaisi niiden kanssa minimiparin. Kaikki yhdeksän informanttia lausuivat sanat äänieristetyssä studiossa, heidän tuotoksensa tallennettiin, ja tallenteet esitettiin lukioluokan oppilaista koostuville kuulijaryhmille. Heidän välittömät kirjalliset havaintonsa, 14350 yksittäistä näytettä, syötettiin analysoitavaksi tätä tarkoitusta varten räätälöityyn relaatiotietokantaan. Havaintoaineistoa analysoitiin kahdesta näkökulmasta, yhtäältä tarkastellen kvantitatiivisia poikkeamia kussakin tavurakenteessa ja toisaalta kunkin informantin vastaavia yksilöllisiä piirteitä tehden huomioita myös laadullisista poikkeamista. Tarvittaessa havaintojen analyysiä täydennettiin foneettisista mittauksista saaduilla tuloksilla. Analyysi kattoi kaikki mahdolliset kvantitatiiviset poikkeamatyypit, joita tällaisessa aineistossa voivat olla vokaalin piteneminen tai lyheneminen kummassakin tavussa tai konsonantin piteneminen tai lyheneminen tavunrajalla. Selkeästi yleisin ja sitkein poikkeamatyyppi aineistossa on toisen tavun vokaalin lyheneminen. Eniten tätä esiintyy tavurakenteissa, joissa on sekä lyhyitä että pitkiä äännesegmenttejä, ja eritoten silloin, kun tavunrajalla on konsonanttiklusteri. Helpoimpia tuottaa ovat sellaiset sanat, joissa kaikki segmentit ovat joko pitkiä tai lyhyitä. Toiseksi yleisin poikkeamatyyppi on ensitavun pitkän vokaalin lyheneminen. Erilaiset tavunrajan kestopoikkeamat, yleisimpänä niistä kaksoiskonsonantin havaitseminen lyhyenä, ovat kokonaisuudessaan haastava ryhmä. Nämä muutokset liittyvät tyypillisesti yhteen niin, että tavunrajalla tapahtuu samanaikaisesti sekä äännesegmenttien lyhenemistä että pitenemistä, mikä johtaa havaintoihin, jotka ovat kenties kauimpana alkuperäisestä tarkoitteestaan ja siten vaikeita ymmärtää. Tutkimus korostaa suomen kvantiteettiopposition hallinnan merkitystä kommunikaation sujuvuuden kannalta. Tutkimustuloksia voidaan hyödyntää koulutusmateriaalin laadinnassa äidinkielenään englantia puhuville suomen kielen oppijoille
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Alexander, Justin Matthew. "Meditations upon durations." Thesis, Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/alexander/AlexanderJ1207.pdf.
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Odabasi, Elvan. "Models For Estimating Construction Duration: An Application For Selected Buildings On The Metu Campus." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610696/index.pdf.
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The duration of construction of a project depends on many factors, such as: cost, location, site characteristics, procurement methods, area of construction, footprint
of the building and its height, etc. It is very important to be able to predict these durations accurately in order to successfully complete a project on time. Various construction duration estimation tools have been developed to make accurate predictions, as &ldquotime is money.&rdquo
The main objective of this study was to develop a model that can be used to predict the construction duration of a project in a reliable and practical way. Contractors can thus use a project'
s characteristics, as given in the tender documents, to estimate the actual amount time it would take them to complete the construction works. In this study, factors affecting the duration of a construction project and models for estimating construction durations were investigated. Within this framework, duration estimation models such as
Bromilow&rsquo
s Time-Cost (BTC) Model and Building Cost Information Service (BCIS) Model were used while Simple Linear Regression (SLR) and Multiple Linear Regression (MLR) analyses were conducted on data related to seven case study buildings that are situated at the Middle East Technical University (METU) campus in Ankara. This data was obtained from the Department of Construction and Technical Works (DCTW) at METU. The closeness in estimation of the regression analyses was investigated and finally an MLR model was obtained which was based on two parameters
the area of the building and the area of its faç
ade. On the other hand, as opposed to studies reported in literature, the effect of cost on duration was not seen to be significant.
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Thune, Lucie Noel. "Sense of Duration." VCU Scholars Compass, 1998. http://scholarscompass.vcu.edu/etd/1279.
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The following writings contain different segments about the concept of time. To best describe certain feelings and thoughts concerning my ideas and work I have used poetry and short stories in a prosaic manner. I also felt it necessary to include some historic facts about the history of time and its measuring devices.
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Athayde, Gustavo M. de. "Duration: novas considerações." reponame:Repositório Institucional do FGV, 1996. http://hdl.handle.net/10438/28.
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Forissier, Aurelie. "Load duration curves analysis." Thesis, KTH, Elektriska energisystem, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119574.
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This report deals with the load duration curves used for development studies on the sub-transmission grid. The aims of grid development studies are firstly to locate the needs for grid reinforcement, then to elaborate a reinforcement strategy and finally to promote the profitability of this reinforcement. This study is about the last step of grid development studies: benefits calculation. The profitability of grid development studies is estimated by comparing grid investment costs and failure costs modelled by the energy not supplied. Load duration curves are used to calculate the energy not supplied due to transmission limitations and therefore to promote the profitability of grid developments (new transmission facilities…). Current load duration curves come from a catalogue created in the early nineties which identifies nine consumption profiles. The aim of this study was to decide whether this catalogue is still valid or not, and, if this catalogue is no longer valid, to elaborate a new catalogue or a homemade software to create on demand, i.e. “à la carte”, load duration curves or load curves for every studied area. Firstly, current catalogue relevance has been analyzed through comparisons with real measured load duration curves of fourteen areas which showed its inadequacy. Then, the study of the real measured load duration curves proved that an accurate catalogue including all the existing load profiles would require a huge number of parameters to describe it. Therefore, a new simple catalogue could be enough to model load profiles on large areas for large scale studies but not for local studies. For these last ones, on demand load duration curves would be preferred to have an appropriate detailed and realistic description of local load behaviour. Finally, a simple method and software to create load duration curves or load curves for every studied area has been developed. Through this analysis, questions were raised of which some could not be answered and this method is not applicable right now. The study needs to be widened in order to establish the links with load levels forecast.
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Sihra, Nirmal. "Sleep duration and mood." Thesis, Loughborough University, 1996. https://dspace.lboro.ac.uk/2134/26145.
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It is widely believed that sleep and mood are interrelated and that prolongation of sleep may have beneficial effects on subsequent mood and general well-being. In the present investigation, it is hypothesised that excess sleep is in fact, detrimental to mood and is associated with a 'Wornout Syndrome', characterised by feelings of fatigue and lethargy, that can persist for up to 5 hours. The studies to be presented here compare the differential effects of Sleep Extension and Sleep Restriction on mood in healthy adults. The experimental design required subjects to undergo one night of Sleep Extension [+2h] and, following an interval of one-week, one night of Sleep Reduction [-2h]. The conditions were counterbalanced. Subjective assessments were conducted hourly on mood states and sleepiness using an adapted Profile of Mood States Questionnaire and the Stanford Sleepiness Scale. Actometers were worn throughout the experimental days and nights. In the first study of 10 subjects results indicated that four subjects were adversely affected by oversleep. Study 2 investigated the effects of sleep duration on mood in 20 healthy adults. Personality factors were assessed using Cattell's 16PF Questionnaire. Subjects maintaining regular sleep schedules reported negative effects of oversleep on subsequent mood. Results indicated that certain personality types were predisposed to the 'Wornout Syndrome' following Sleep Extension. In Study 3, thirty-four subjects were selected on the basis of personality type. It was hypothesised that Introverts, Morning types, Emotionally Tenderminded and Low Impulsives would report symptoms characteristic of the 'Wornout Syndrome' following one night of Sleep Extension. This was confirmed by reports of increased fatigue, diminished vigor, and increased confusion following Sleep Extension. Oversleeping produced greater detrimental effects on mood than a comparable reduction in sleep duration. There are many similarities in symptomatology between the 'Wornout Syndrome' and Chronic Fatigue Syndrome (CFS), specifically, intense fatigue and impaired concentration. Interestingly, chronically fatigued patients often complain of sleep disturbance, and spend much of their time resting in bed. It was hypothesised that the 'Wornout Syndrome' may be a confounding factor in the symptomatology of CFS. As a clinical dimension, twelve subjects were investigated polysomnographically [six were CFS patients]. Findings indicated that CFS patients acquired sleep of longer duration than controls. In addition to excess nocturnal sleep, CFS patients were taking daytime naps. EEG data indicated that these individuals obtained twice the normal amount of slow wave sleep. CFS sufferers may be better advised to regulate their sleep habits and reduce their total sleep time to avoid the confounding effects of the 'Wornout Syndrome'.
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Castaño, Maria Soledad. "Hétérogénéité dans des processus de développement cachés : inférence et analyse de populations structurées en environnements fluctuants." Thesis, Antilles, 2017. http://www.theses.fr/2017ANTI0124/document.
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Codakia orbicularis est un mollusque bivalve appartenant à la famille des Lucinidae et établissant des symbioses avec des bactéries sulfo-oxydantes (symbiotes) au sein de ses branchies. Dans l’hypothèse où toute symbiose nécessite une régulation par des molécules de dialogue, une étude chimique exhaustive pourrait aboutir à la mise en évidence des métabolites impliqués. Le travail de ce manuscrit porte donc sur l'isolement de métabolites secondaires à partir des branchies de ce bivalve et sur l'évaluation de l'activité antibactérienne des molécules isolées. Douze composés ont été isolés des branchies de Codakia orbicularis et leurs structures ont été déterminées par les méthodes spectroscopiques usuelles. Parmi ces molécules, une seule est nouvelle et a été nommée orbicularisine. Elle présente un squelette indolone spirotetracyclique inédit. Parmi les molécules isolées, seules quatre d’entre elles présentent une activité antibactérienne à savoir le soufre S8, la 4-hydroxybenzaldéhyde et deux monoglycérolipides. L'orbicularisine est inactive contre un panel de lignées cellulaires cancéreuses et de kinases. Le nouveau squelette de l’orbicularisine pourrait permettre d'aboutir à une nouvelle famille de molécules par synthèse organique et ainsi d'accroître la diversité moléculaire autour de ce motif inédit. Il sera également intéressant de déterminer l'origine des molécules isolées (procaryote ou eucaryote), particulièrement pour l’orbicularisine, et leurs rôles dans le cadre de la symbiose. Les résultats chimiques obtenus sur C. orbicularis et sur les Lucinidae en général sont intéressants puisque les espèces côtières appartenant aux bivalves ont été peu exploitées en chimie jusqu’à ce jourCodakia orbicularis is a bivalve mollusk belonging to the family Lucinidae harboring sulfur-oxidizing bacterial endosymbionts within its gills. Considering that any symbiosis is most likely regulated by dialogue molecules, an exhaustive chemical study could lead to identify the involved metabolites. Thus, the aim of this thesis focuses on the isolation of secondary metabolites from the gills of this bivalve and the evaluation of the antibacterial activity of the isolated molecules. Twelve compounds were isolated from the gills of Codakia orbicularis and their structures were determined by usual spectroscopic methods. Among these molecules, only one presented a new structure and has been named orbicularisine. The latter presents an undescribed spirotetracyclic indolone skeleton. Regarding the biological activities, among the isolated molecules, only four of them identified as S8 sulfur, 4-hydroxybenzaldehyde and two monoglycerolipids presented an antibacterial activity. Orbicularisine was inactive against a panel of cell lines and kinase. The orbicularisine new skeleton is an interesting start for the synthesis of new family of molecules, thus enhancing its molecular diversity. It will be interesting to determine the origin of the isolated molecules (prokaryotic or eukaryotic), especially for the new orbicularisine, and their roles in the frame of the symbiosis. The chemical results obtained on C. orbicularis and on lucinids in general are interesting since the coastal species belonging to Bivalves have not been chemically explored
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Fisher, Uri Joseph. "Military entrepreneurship and war duration." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3273670.
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Zhai, Yongliang. "Dynamic duration of load models." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36958.
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The duration of load effect is a distinctive and important characteristic of wood strength. It refers to the fact that wood products can usually sustain a high load for a short time but the products may deteriorate and break in the long run.
Modelling the duration of load effect and testing wood for specific properties of this effect are important in formulating wood construction standards.
Damage accumulation models have been proposed by authors to model the duration of load effects. The models assume that damage is accumulated over time according to the load history, and once the accumulated damage reaches a threshold value, the board will break. Different authors have designed different experiments and proposed different methods for estimating the model parameters.
In this work, we consider several damage accumulation models, with a focus on the U.S. model. We investigate the effects of the distributional assumptions for the models, and propose several methods to estimate parameters in the models. Our proposed methods are evaluated via simulation studies. Two real datasets are present for illustration.
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Khoshbin, Ehteram. "Modelling two stage duration process." Thesis, Lancaster University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310460.
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Sykora, Jiri S. M. Massachusetts Institute of Technology. "Vacancy durations in the office market." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/123599.
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Thesis: S.M. in Real Estate Development, Massachusetts Institute of Technology, Program in Real Estate Development in conjunction with the Center for Real Estate, 2019Cataloged from PDF version of thesis.
Includes bibliographical references (pages 49-50).
The durations of other indicators have been researched extensively in real estate studies, primarily the time on market and the duration of residence in housing units. Despite their importance, empirical research on the duration of vacancies is relatively limited and focused mainly on the housing sector. This paper aims to fill this gap and analyze the determinants of vacancy durations in the office sector. The analysis is based on a dataset of individual office suites located in New York City, NY that became vacant between 2012 and 2015. Vacancy durations are a form of time-to-event data and as such can be examined using survival analysis. We present several parametric and non-parametric survival models. Four key characteristics -- unit size, asking rent, building height, and floor number -- are found significant across all model specifications. Specifically, vacancy durations are affected the most by unit size and asking rent. Survival probabilities are found to considerably vary over time, which appears to be driven by variations in employment growth.
by Jiri Sykora.
S.M. in Real Estate Development
S.M.inRealEstateDevelopment Massachusetts Institute of Technology, Program in Real Estate Development in conjunction with the Center for Real Estate
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Van, Heerden Charl Johannes. "Phoneme duration modelling for speaker verification." Diss., Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-06262009-150945/.
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Boudreau, Christian. "Duration data analysis in longitudinal surveys." Waterloo, Ont. : University of Waterloo, 2003. http://etd.uwaterloo.ca/etd/cboudrea2003.pdf.
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Thesis (Ph.D.)--University of Waterloo, 2003."A thesis presented to the University of Waterloo in fulfillment of the thesis requirement for the degree of Doctor of Philosophy in Statistics". Includes bibliographical references. Also available in microfiche format.
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Cunningham, David E. "Veto players and civil war duration /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3241818.
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Winkler, Isabell. "The Processing of Frequency and Duration." Doctoral thesis, Universitätsbibliothek Chemnitz, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200900917.
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Die Häufigkeit und die Dauer, mit der Ereignisse auftreten, sind zwei grundlegende Merkmale des Geschehens in unserer Umwelt. Sie beeinflussen unser Erleben und Verhalten und wirken sich auf Lernprozesse aus. In vielen Situationen müssen wir in der Lage sein, Unterschiede in Auftretenshäufigkeit und –dauer wahrzunehmen, um angemessen zu reagieren und die richtigen Entscheidungen zu treffen.
In der vorliegenden Arbeit wird die menschliche Verarbeitung von Häufigkeit und Dauer anhand von Häufigkeits- und Zeitschätzungen untersucht. In bisherigen Untersuchungen wurde bereits festgestellt, dass sich die Wahrnehmungen von Häufigkeit und Dauer unter bestimmten Umständen gegenseitig beeinflussen: So werden Häufigkeiten umso größer geschätzt, je länger die entsprechenden Stimuli dargeboten werden; außerdem wird die Stimulusdauer als umso länger beurteilt, je öfter die Stimuli präsentiert werden. Auf der Basis dieser Befunde wurde vermutet, dass der Verarbeitung von Häufigkeit und Zeit ein gemeinsamer Verarbeitungsmechanismus zugrunde liegt. Tatsächlich wurde dies schon im Rahmen tierexperimenteller Studien bestätigt. Weiterhin gibt es neuropsychologische Befunde, die darauf hindeuten, dass Häufigkeit und Zeit in identischen Hirnstrukturen verarbeitet werden.
Allerdings gibt es auch Befunde zur menschlichen Häufigkeits- und Zeitverarbeitung, die die Annahme eines gemeinsamen Verarbeitungsmechanismus in Frage stellt. Diese Studien zeigten eine asymmetrische Beziehung zwischen Häufigkeits- und Zeitschätzungen: Häufigkeitsurteile waren dabei sehr präzise und relativ unbeeinflusst von der Darbietungsdauer, während Zeiturteile wesentlich unpräziser waren und stark von der Stimulushäufigkeit beeinflusst wurden.
Die vorliegende Arbeit ist motiviert durch die Annahme, dass es sich bei dem gefundenen asymmetrischen Beziehungsmuster um einen Forschungsartefakt handelt. Die Ursache für das beschriebene Ungleichgewicht zwischen Häufigkeits- und Zeiturteilen ist vermutlich die Tatsache, dass die Verarbeitung von Häufigkeit und Zeit unterschiedlich viel Aufmerksamkeit benötigt. Die Enkodierung von Stimulushäufigkeiten benötigt nur relativ wenig Aufmerksamkeit. Für eine vollständige Enkodierung der Darbietungsdauer ist hingegen wesentlich mehr Aufmerksamkeit nötig, die über die gesamte Präsentationsdauer des jeweiligen Stimulus‘ hinweg aufrecht erhalten werden muss. In den Studien, in denen ein asymmetrischer Zusammenhang gefunden wurde, wurden meist sehr viele Stimuli ohne spezielle Bedeutsamkeit für die Probanden präsentiert (z.B. Wortlisten). Vermutlich wurde deshalb nur wenig Aufmerksamkeit auf die Stimuli gerichtet, so dass zwar die Häufigkeit, nicht jedoch die Darbietungsdauer, vollständig enkodiert wurde. Die gefundene geringe Zeitsensitivität sowie die hohen Sensitivität für Häufigkeiten bestätigen diese Annahme. Ein asymmetrisches Beziehungsmuster ist unter diesen Umständen kaum verwunderlich, da zwar die gut differenzierten Häufigkeitsurteile viel Einfluss auf die kaum hinsichtlich der tatsächlichen Darbietungszeit diskriminierenden Zeiturteile haben können, umgekehrt ist dies jedoch kaum möglich. Diese Annahmen werden im Rahmen von drei Manuskripten überprüft.
Im ersten Manuskript wurden die Auswirkungen kognitiver Beanspruchung auf die Häufigkeits- und Zeitverarbeitung untersucht. Die kognitive Beanspruchung wurde hierbei variiert anhand der Anzahl der zu verarbeitenden Stimuli sowie anhand der Aufgabenkomplexität. Eine hohe kognitive Beanspruchung geht dabei mit einer reduzierten Aufmerksamkeit für die einzelnen Stimuli einher. Bei hoher kognitiver Beanspruchung zeigten sich eine niedrige Zeitsensitivität und ein asymmetrisches Beziehungsmuster zwischen Häufigkeits- und Zeiturteilen. Bei geringer kognitiver Beanspruchung hingegen war die Zeitsensitivität höher und die Urteile beeinflussten sich gegenseitig.
Im zweiten Manuskript lenkten wir die Aufmerksamkeit der Teilnehmer zum einen durch die Stimulusart (neutrale Worte versus emotionale Bilder) auf die Stimuli, zum anderen durch eine Aufgabe, bei der die Aufmerksamkeit während der gesamten Stimulusdarbietung auf die Stimuli gerichtet werden musste. Dabei zeigte sich die größte Zeitsensitivität, wenn emotionale Bilder gezeigt wurden und zusätzliche Aufmerksamkeit durchgehend auf die Stimuli gerichtet wurde. In dieser Bedingung fand sich zudem die größte gegenseitige Beeinflussung zwischen Häufigkeits- und Zeiturteilen.
Im dritten Manuskript untersuchten wir den Effekt der Aufmerksamkeit auf die Häufigkeits- und Zeiturteile in realitätsnäheren experimentellen Settings. In der ersten Studie lenkten wir die Aufmerksamkeit der Probanden während der gesamten Präsentationsdauer auf die Stimuli (durch die Darbietung von Straßenverkehrssimulationen, in denen während der gesamten Präsentationsdauer Bewegung zu sehen war). Die Zeitsensitivität war hierbei hoch und Häufigkeits- und Zeiturteile beeinflussten sich gegenseitig. In der zweiten Studie wurde mittels einer Zweitaufgabe Aufmerksamkeit von den Stimuli abgezogen. Je mehr Aufmerksamkeit von den Stimuli abgelenkt wurde, desto geringer war die Zeitsensitivität und desto kleiner die gegenseitige Beeinflussung der Häufigkeits- und Zeiturteile.
Die Befunde deuten allesamt auf einen gemeinsamen Verarbeitungsmechanismus von Häufigkeit und Zeit hin. In der vorliegenden Arbeit wird die Anwendung der gewonnenen Erkenntnisse für Entwicklung eines Erklärungsmodells der menschlichen Häufigkeits- und Zeitverarbeitung diskutiert.
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Boudreau, Christian. "Duration Data Analysis in Longitudinal Survey." Thesis, University of Waterloo, 2003. http://hdl.handle.net/10012/1043.
Full textAbstract:
Considerable amounts of event history data are collected through longitudinal surveys. These surveys have many particularities or features that are the results of the dynamic nature of the population under study and of the fact that data collected through longitudinal surveys involve the use of complex survey designs, with clustering and stratification. These particularities include: attrition, seam-effect, censoring, left-truncation and complications in the variance estimation due to the use of complex survey designs. This thesis focuses on the last two points.
Statistical methods based on the stratified Cox proportional hazards model that account for intra-cluster dependence, when the sampling design is uninformative, are proposed. This is achieved using the theory of estimating equations in conjunction with empirical process theory. Issues concerning analytic inference from survey data and the use of weighted versus unweighted procedures are also discussed. The proposed methodology is applied to data from the U. S. Survey of Income and Program Participation (SIPP) and data from the Canadian Survey of Labour and Income Dynamics (SLID).
Finally, different statistical methods for handling left-truncated sojourns are explored and compared. These include the conditional partial likelihood and other methods, based on the Exponential or the Weibull distributions.
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Freedman, Ruth Janine. "Duration and bond returns : empirical tests." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24396.
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The purpose of this thesis is to empirically investigate the role of duration in explaining bond price volatility caused by interest rate movements. Specifically, Canadian and American market data are used to test whether Macaulay/Fisher and Weil duration is an adequate measure of basis risk for default-free government bonds during the 20-year sample period January 1961 to December 1980.
The most important result of the study is that in either a Canadian or an American context there is no significant evidence to suggest that, on average, higher duration bonds earn higher returns. Specifically, there appears to be a negative, although insignificant, relationship on average between bond returns and duration. A possible explanation for this result is that interest rates have trended upwards over most of the sample period. American results suggest that when changes in the level of interest rates have been filtered out there is a positive, although insignificant, relationship between bond returns and duration.
Other results of the study are that coupon rates are positively related to bond returns (perhaps due to a tax effect), and that bond pricing errors are often related to subsequent returns.Business, Sauder School of
Graduate
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Campolieti, Michele. "Bayesian estimation of discrete duration models." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0001/NQ27884.pdf.
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Lou, Zhijian. "Determination of unemployment duration in Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ64607.pdf.
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Lou, Zhijian 1957. "Determination of unemployment duration in Canada." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36641.
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In an effort to explore various difficulties in the process of reemployment, the focus of this study is how, to what extent, and in what way length of unemployment duration is generated by the interplay between the structural characteristics of the labor market and the individual characteristics of unemployed workers. The structural resources are conceptualized in terms of (1) different types of reemployment, and (2) economic sectors. It turns out that the insertion of labor market structures into research on unemployment duration is quite valuable in improving our understanding of individual reemployment behavior.The findings show that reemployment through job recalls is relatively easier than through job switches. Even though many unemployed workers remained to benefit from the structural buffer of internal labor markets in their struggle for reemployment, workers losing core-sector jobs are found to have more difficulty in switching to a new job relative to those losing peripheral jobs. The finding illustrates a critical weakness of internal labor markets in reallocating unemployed workers.
Furthermore, the impact of the labor market location of lost jobs is also observed in both the manner and the extent to which the individual attributes of unemployed workers affect the process of reemployment. (1) More education substantially improves the reemployment chances of workers losing core-services jobs, but not workers unemployed from other sectors. (2) The reemployment probability of workers losing core-services jobs is increased with an improvement in general education whereas the reemployment probabilities of workers losing core goods-production jobs tend to increase with an accumulation in firm-specific skills. (3) Men tend to maintain their reemployment advantage through their access to internal labor markets whereas women improve their reemployment probability by benefiting from job expansion in service industries. (4) Experienced core-service workers tend to have a shorter unemployment duration than young ones when their jobs are available for recall, whereas experienced peripheral goods production workers often have a competitive disadvantage in switching to a new job. And (5) UI benefits slow down the job-recall rate substantially but have little impact on the individual behavior of searching for a new job. The problem of timing termination of unemployment duration to coincide with exhaustion of UI benefits is much more severe for the job-recall rate than for the job-switch rate.
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Reis, Alfredo Duarte Egidio dos. "On the duration of negative surplus." Thesis, Heriot-Watt University, 1994. http://hdl.handle.net/10399/1389.
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Wang, Wenqun. "Modelling and predicting traffic incident duration." Thesis, University of Leeds, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426846.
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Boaventura, Guimareas Dumangane Montezuma. "Essays on duration response measurement error." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368683.
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Chaurasia, Priyanka. "Incorporating duration information in activity recognition." Thesis, Ulster University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.674917.
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Activity recognition is a key component of patient management in smart homes where high-level activities can be learned from low-level sensor data. Different activities have different durations. In addition different people may take different amounts of time to complete the same activity. Activity duration information can therefore be considered as a potentially useful feature in assessing user health and cognitive status, and in distinguishing between different activities. The objective of this thesis is to develop methods that incorporate duration-based information in activity recognition and thus improve activity prediction performance. Activity duration information has been integrated in an existing probabilistic model and improvements in activity recognition analysed. For the purpose of computational modelling, duration data were discretised. A probabilistic learning model was built using the joint probability distribution over different activities, representing behavioural patterns of the users in performing a range of activities. Each activity was predicted based on the conditional probability of the activity given the sequence of sensor activations, the time of activation and the duration of the activity. The built model demonstrated nearly 2% improvement in the prediction of activities when duration information was included. The derived model with enhanced recognition capability motivated the development of a duration-based decision making framework for a potential online support tool. The aim was to combine two incomplete aspects of online sensor data: incomplete activity duration and partially observed sensor activations within such a framework. The two aspects, when integrated can improve the online prediction of user activity. As an activity progresses, these two aspects change over time; hence the prediction of the current activity will also change accordingly. Further work related to activity durations involved exploring different clustering approaches for the purpose of discretisation of duration data related to a set of activities and automation of the discretisation process. The work also addressed issues associated with the discretisation problem when working with a dataset of limited size, where prediction of the statistical model parameters is difficult. In summary, the research presented in this thesis contributes to methodologies to enhance activity recognition systems for smart homes based on the incorporation of activity duration information. The advantage of employing activity duration data in activity recognition was also demonstrated on datasets from external smart home environments, where different activities were distinguished based on durations along with other sensor attributes.
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Hom, Conan Lee 1973. "Regional characteristics of rainstorm durations and intensities." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47422.
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Finical, Stephanie. "Duration of a sung token in pitch matching as a function of the duration of the response." Connect to resource, 2007. http://hdl.handle.net/1811/25253.
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Thesis (Honors)--Ohio State University, 2007.Title from first page of PDF file. Document formatted into pages: contains iv, 18 p.; also includes graphics. Includes bibliographical references (p. 18). Available online via Ohio State University's Knowledge Bank.
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Carter, Evan C. "Religious Cognition and Duration of Maintained Grip." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_theses/23.
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Recent work suggests that the links between religious belief and behavior with a variety of positive outcomes (e.g., longer life, more marital satisfaction, scholastic achievement, better health behaviors) may be partially explained by religious belief systems' ability to foster self-control and self-regulation. The current investigation sought to explore this hypothesis by determining if induction of religious cognition (through a supraliminal religious prime) could increase behavioral self-control, operationalized as performance on a maintained grip task. Using 118 participants, the author tested whether nonconscious exposure to religious content would increase the amount of time that participants were willing to physically persist at two rounds of the maintained grip task as compared to a control group. A within-subjects trial-by-prime interaction was found (the prime appeared to cause participants to persist at the task for less time during the first trial, but not the second) and a between-subjects sex-by-prime interaction was found (on average, men given the religious prime held their grip for less time than did men in the control group, whereas no differences were found between women). Findings are discussed in terms of the link between religion and self-control and future directions are suggested.
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Goubanova, Olga. "Bayesian networks for predicting duration of phones." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/29125.
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The duration of a phonetic segment (phone) is usually modelled with a database of feature vectors, that consist of a set of linguistic factors’ (attributes’). There have been a number of models developed for predicting a phone’s duration, ranging from rule-based to neural nets to classification and regression tree (CART) to sums-of-products (SoP) models duration is predicted by a decision tree. In our work, we use a Bayesian belief network (BN) consisting of discrete nodes for the linguistic factors and a single continuous node for the phone’s duration. Interactions between factors are represented as conditional dependency relations in this graphical model. During training, the parameters of the belief network are learned via the Expectation Maximisation (EM) algorithm. The duration of each phone in the test set is then predicted via Bayesian inference: given the parameters of the belief network, we calculate the probability of a phone taking on a particular duration given the observations of the linguistic variables. The duration value with the maximum probability is chosen as the phone’s duration. We contrasted the results of the belief network model with those of the sums of products and CART models. We trained and tested all three models on the same data. In terms of the RMS error our BN model performs better than both CART and SoP models. In terms of the correlation coefficient, our BN model performs better than SoP model, and no worse than CART model. We believe our Bayesian model has many advantages compared to CART and SoP models. For instance, it captures the factors’ interactions in a concise way by causal relationships among the variables in the graphical model. The Bayesian model also makes robust predictions of phone duration in cases of missing or hidden data.
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Sargent, Risa D. "Male phase duration in a protandrous plant." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0012/MQ61496.pdf.
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Podugu, Sireesha P. Ferrari Michael B. "Long duration calcium transients inhibit sarcomere assembly." Diss., UMK access, 2006.
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Thesis (M.S.)--School of Biological Sciences. University of Missouri--Kansas City, 2006."A thesis in cellular and molecular biology." Typescript. Advisor: Michael B. Ferrari. Title from "catalog record" of the print edition Description based on contents viewed Nov. 1, 2007. Includes bibliographical references (leaves 48-52). Online version of the print edition.
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Nivorozhkin, Anton. "Essays on unemployment duration and programme evalution /." Göteborg : Department of Economics, School of Business, Economics and Law, Göteborg Univeersity, 2006. http://www.handels.gu.se/epc/archive/00004686/01/Nivorozhkin%5Fdiss.pdf.
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Hverven, Stine Myhre. "Laser Induced Incandescence with Long Pulse Duration." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for fysikk, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22436.
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Laser Induced Incandescence (LII) is a technique used to observe soot concentration and particle size in a flame. The LII signal is captured by an intensified CCD camera. Laser light impacts and heats soot particles within the flame, and the resulting intensity signal is detected. The LII signal is the radiation from the soot particles, and its temporal profile depends on many physical processes. The collected intensity images are further analyzed to generate the temporal profile of the LII signal.Detailed LII measurements were performed in order to study an unknown phenomenon which first appeared in a previous experiment at SINTEF. Two peaks were found to appear in the temporal LII signal when laser pulses of pulse duration longer than 100 ns were used.The main part of this thesis was dedicated to preparing the experimental setup, running LII measurements and analyzing temporal LII profiles. The LII measurements were performed on a small laminar ethylene flame with varying laser pulse duration and pulse fluence. An Nd:YAG laser with wavelength 532 nm was used, and later the first harmonic 1064 nm laser light. The temporal laser profiles had pulse duration in the range 50 to 450 ns, all rectangular in shape. The laser energy incident on the ethylene flame was varied using a combination of a half-wave plate and a beamsplitter.Several hypotheses were presented after the previous experiments at SINTEF, and these have been studied more carefully. As an example, areas within the flame where the soot?s morphological characteristics are different were analyzed and found not to have an effect. PAH-fluorescence and contribution from C2-radicals have also been ruled out as possible causes of the phenomenon. The cause of the two peaks appearing in the temporal LII signal is still unknown, but the results show some interesting aspects of the phenomenon.For the two peaks to appear, a certain fluence threshold must be reached. Studies of the time-integrated LII signal vs. laser pulse fluence revealed a new profile not previously seen. Such graphs have previously shown a saturation curve, saturating around 0.4-0.5 J/cm2 for the 1064 nm laser light. The results presented in this thesis show that this signal begins to increase again for higher fluence values. It is when the signal begins to increase that the two peaks become visible in the temporal LII profiles.The phenomenon?s irradiance dependence is also analyzed, but more data is required to give a decisive conclusion. It might be that the two peaks are present in studies using 10 ns pulse duration, but that due to the short time frame only a single peak is seen.Possible causes of the two peak phenomenon are presented and discussed. Advise on further research, both experimental and computational, is also presented. The two peaks might be caused by morphological changes in the soot, or by creation of new particles due to vaporization. It might also be caused by unknown processes the soot undergoes when impacted by the laser beam.
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Ganzenmüller, Stephanie. "Effects of sensory feedback on duration reproduction." Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-165747.
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Most studies, investigating human time perception, have demonstrated a difference between subjective and objective timing. Very common are, for example, results showing that visual intervals are judged shorter than physically equivalent auditory intervals. Recent studies have also found differences between motor and perceptual timing. Considering those perceived differences, the idea has been proposed that the brain might employ distributed (modality- specific) timing mechanisms rather than one amodal timing mechanism. Distributed timing mechanisms and therefore independent temporal estimates would be convenient in the computation for reliability-based multisensory or sensorimotor integration, as predicted by Bayesian inference. Several studies have shown that multisensory temporal estimates can be predicted by reliability-based integration models, as for example the Maximum Likelihood Estimation (MLE) model. Reliability-based integration studies in time research are still fairly rare and discussed controversially, and especially studies investigating sensorimotor integration are mostly missing. The aim of this cumulative thesis was to investigate sensorimotor temporal reproduction with a focus on the influence of sensory (mainly auditory) feedback on motor timing. Here fore, in all studies a sensorimotor temporal reproduction paradigm was employed, and sensory and motor estimates were treated as different/independent estimates. First, we investigated the effect of onset and offset delayed sensory feedback on temporal reproduction (Chapter 2.1). Second, perceptual and motor timing were compared explicitly and then a reliability-based model was used to predict the observed sensorimotor reproduction times (Chapter 2.2). In a third study, we manipulated the prior representation of the standard duration, using different adaptation conditions (Chapter 2.3). The findings showed that if the onset of a feedback stimulus was delayed in relation to an action (in contrast to when the feedback signal was started before the action), reproduced durations increased immediately, as soon as a delay is introduced. Offset-delayed sensory feedback, on the other hand, only induced a minor decrease in reproduction times and this effect could only be observed with auditory feedback. In comparison to auditory comparison estimates, which were shown to be fairly precise, pure motor reproduction as well as auditory reproduction was found to be consistently overestimated. The observed overestimation bias in auditory reproduction was reduced, compared to pure motor reproduction. This pattern of result could be shown for various standard durations and different signal-to-noise ratios (SNR) in the compared/reproduced tones. Further, a reliability-based model
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predicted observed auditory reproduction biases successfully. In the third study, we could show that shifting the temporal range of accuracy feedback, manipulating the SNR of the reproduced tone, as well as introducing a manipulation of the reproduced tone onset, led to significant changes in the prior representation of the standard duration. Only manipulating the reproduced tone onset during the adaptation phase induced a reduction of auditory weights, which could be observed during the test phase. Additional trial-wise analysis confirmed that the adapted prior representation is shifted back to normal dynamically over time, once no accuracy feedback is provided anymore. The differences between observed sensory and motor estimates of time are discussed. We concluded that the finding that onset and offset delay influenced reproduction performance differentially implies that participants rather rely on the sensory feedback as a start- timing signal (at least if a causal relationship between action and sensory feedback can be established), while the motor stop is used as primary stop-timing signal. Observed sensorimotor reproduction biases and variability could be described as the weighted integration of the auditory estimate and the motor estimate. The integration reflects the brain combines multiple timing signals to improve overall performance. The prior knowledge of the standard duration in the reference memory is updated dynamically in that current sensorimotor estimates are constantly integrated with the history of duration estimates. In the end, overall implications of all the results for time perception, as well as sensory integration research are discussed. In summary, this thesis helps to improve our knowledge about sensorimotor temporal integration in a sensorimotor reproduction task on the basis of behavioral findings as well as probabilistic modeling.
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Gin, Andrew. "Building a Secure Short Duration Transaction Network." Thesis, University of Canterbury. Computer Science and Software Engineering, 2007. http://hdl.handle.net/10092/1188.
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The objective of this project was to design and test a secure IP-based architecture suitable for short duration transactions. This included the development of a prototype test-bed in which various operating scenarios (such as cryptographic options, various IP-based architectures and fault tolerance) were demonstrated. A solution based on SIP secured with TLS was tested on two IP based architectures. Total time, CPU time and heap usage was measured for each architecture and encryption scheme to examine the viability of such a solution. The results showed that the proposed solution stack was able to complete transactions in reasonable time and was able to recover from transaction processor failure. This research has demonstrated a possible architecture and protocol stack suitable for IP-based transaction networks. The benefits of an IP-based transaction network include reduced operating costs for network providers and clients, as shared IP infrastructure is used, instead of maintaining a separate IP and X.25 network.
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Boettcher, Joan. "Interaction of factors related to lactation duration." Virtual Press, 1998. http://liblink.bsu.edu/uhtbin/catkey/1074546.
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The national health promotion goals for increasing breastfeeding initiation rates to at least 75% of all mothers and six month breastfeeding continuation rates of at least 50% by the year 2000 do not seem to be obtainable. These goals require new insight into what motivates a new mother to continue to breastfeed. This study identified perceived social support and interpersonal dependency as potential factors associated to lactation duration, based upon the previous breastfeeding experience of the mother. Inexperienced breastfeeding mothers perceived more total support, task support and informational support than mothers with previous breastfeeding experience. This study did not correlate the amount of perceived support to lactation duration. An ancillary finding was that women providing a combination of breast milk and artificial baby milk feeds had a significantly higher lack of social self-confidence than mothers providing breastmilk exclusively.Department of Family and Consumer Sciences
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Guenette, Gerald Roger. "A fully scaled short duration turbine experiment." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15249.
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Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND AERO.
Includes bibliographical references.
by Gerald Roger Guenette, Jr.
Sc.D.
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Smith, David Andrew. "Millisecond duration thermal processing of silicon layers." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335788.
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Gallais, Cedric. "Effect of vibration exposure duration on discomfort." Thesis, University of Southampton, 2008. https://eprints.soton.ac.uk/72157/.
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The comfort of a seated person exposed to vibration is known to depend on the magnitude, frequency content, and direction of the excitation. A review of the literature showed that very little is known about the effects of the duration of exposure to vibration on comfort. This thesis investigates the effects of body support, frequency, waveform, and direction of excitation on the Subjective Discomfort Time-Dependency (SDTD) during vibration so as to improve understanding of the mechanisms involved (e.g. the biodynamic responses of the body and muscle activity) and elaborate a model predicting how discomfort evolves with exposure duration. To achieve these objectives, a new method of measuring the discomfort time-dependency was developed and tested. The Subjective Discomfort Time-Dependency has been investigated in 27 experimental sessions, each with twelve subjects seated on a conventional car seat. In each session, subjects were exposed to one stimulus. The new developed method requires the subjects to adjust the magnitude of the vibration in order to keep constant their discomfort. The SDTD was obtained by measuring the platform acceleration over the exposure duration. At specific time-intervals, subjects were also asked to indicate the locations of their discomfort and provide discomfort ratings for these locations. Results showed that the amount of vibration to achieve a constant level of discomfort decreased over time (mainly during the first 15 minutes of exposure). This implies that the sensitivity of vibration increases with duration. Fore-and-aft excitations generated a greater SDTD for most stimuli. For 1-Hz lateral sinusoidal motion, the sensitivity of vibration increased at a greater rate with a harness than without. Stimuli at 1 Hz produced SDTD that were less dependent on the duration of exposure than stimuli at higher frequencies. The waveforms of the vibration had little effect on the SDTD. The discomfort rating showed that prolonged exposure to vibration produced discomfort mainly at the neck. Because discomfort was mainly felt at the neck and that the SDTD depended on the frequency, it was hypothesised that the type of neck muscle activity produced during exposure to vibration depends on the frequency. Neck muscle activity was measured with 12 seated subjects during 10 minutes of fore-and-aft sinusoidal vibration. The r.m.s. magnitudes of the raw EMG and of the phasic and tonic components of the EMG were calculated (it was assumed that phasic muscle activity arose from the periodic vibration whereas the tonic muscle activity was needed to respond to a static load). Results showed that the frequency of vibration had no effect on the EMG r.m.s values but affected the phasic and tonic components of the EMG. Phasic activity was greatest at 1 Hz and decreased as the frequency increased. Tonic activity showed the opposite tendency. As for the SDTD studies, the frequency of excitation seems to have an effect on the phasic and tonic components of the neck muscle activity. Phasic and tonic neck muscle activities represent different types of head motions. Because the content of phasic and tonic activities of the EMG signal seems to be linked with the effects of vibration exposure duration on discomfort, it was hypothesised that predicting the head motions may help estimating the comfort timedependency. A three degree-of-freedom lumped parameter model was developed to predict floor-to-head transmissibility. The model was then calibrated to estimate the head motions using the floor-to-head, seat-tohead, and seat transmissibility measured with 12 subjects, exposed to fore-and-aft sinusoidal, narrow-band random, and broad-band random vibration. Results showed that the model can estimate the head motions around the frequencies of resonances (mode shapes), but requires improvement to be accurate at the other frequencies. The estimated mode shapes showed three types of head motions: at 1.4 Hz the head and neck moved in phase; at 3.5 Hz, there was a resonance of the backrest and the head and neck moved in phase, but with a greater head motion than neck motion; and at 6.9 Hz the head and neck moved out of phase. The subjective, physiological, and biodynamic studies suggest that the SDTD increases when the neck muscles attempt to control head motions by producing greater tonic, and less phasic, activity. The lumped parameter model identified through the mode shapes three types of head motions corresponding to different comfort time-dependencies. It was hypothesized that the phase and modulus of the seat-to-head transmissibility may indicate the amount of phasic and tonic activity produced. Through neck muscle activity, a model predicting seat-to-head transmissibility may also predict the time-dependency of discomfort. This thesis proposes a new method for determining the time-dependency of discomfort caused by whole-body vibration. Discomfort time-dependencies have been shown to depend on the frequency of vibration, direction of excitation, and body support. Mechanisms responsible for the discomfort time-dependency have been proposed.
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Kocher, Robert Joseph. "Building Duration: A House Living Toward Death." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78314.
Full textAbstract:
Life is a transition through stages, framed by birth and death. We transition through life in a nonlinear fashion, moving sometimes closer to, and sometimes farther from, rest. Daily, we rise for living and fall to rest. Daily, we prepare for activity and prepare for sleep. Daily we age and endure, but our burdens may lighten with the coming of Spring or a new member to the family.
In reverence to the stages of life, I have designed a house living for death - a house that provides a meaningful setting for the stages of life and our daily transitions. The house provides a dwelling for a cemetery caretaker, whose very vocation is a daily encounter with death.
The house, living for death, is composed of aspects that call the dweller to death and to life. Death is reflected in a stone foundation and walls for the private quarters of the home, for rest and daily preparations. These ground the dweller in ultimate rest. Life is reflected in rooms of timber that create a place for nourishment, entertaining, and leisure during the day. The centerpiece of the house is a stone hearth that adjoins the stages of the house - stone and timber, death and life. Just as the stages of life are nonlinear, the stone and timber construction of the house meet and acknowledge each other and their respective roles. For example, the sleeping quarters have a stone foundation but east-facing walls of wood remind the sleeper that activity calls and that rest in the house is not permanent.
A key feature of the home is its moment of transition to the west, where the dweller is prepared to encounter and acknowledge final rest in the attached cemetery. Two rotating doors create a space for the caretaker to access the cemetery through a moment of transition. In this moment, the caretaker accesses her tools and reorients her mind. Transitioning to the outdoors, the caretaker must ascend to the cemetery and pauses on landing when eye-height with her charges, the headstones. Upon return from the cemetery, the moment of transition is a moment to remove dirt, clean, and again reorient to the living.Master of Architecture
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Alamad, Ruba Amin. "SURGERY DURATION ESTIMATION USING MULTI-REGRESSION MODEL." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1498073495501962.
Full text
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"A Rhythmic Analysis of Scottish Gaelic Using Durational Metrics." Master's thesis, 2020. http://hdl.handle.net/2286/R.I.57372.
Full textAbstract:
abstract: Languages have long been studied through the rhythm class framework, which discriminates them into separate classes on the basis of shared rhythmic properties. Originally these differences were attributed to the isochronous timing of different prosodic units, such as stress intervals in “stress-timed” languages and syllables in “syllable-timed” languages. More recent work has turned to durational metrics as a means of evaluating rhythm class, by measuring the variability and proportion of segmental intervals in the speech stream. Both isochrony and durational metrics are no longer viewed as correlative with natural language rhythm, but durational metrics in particular have remained prevalent in the literature. So long as the conclusions of durational metrics are not overextended, their analysis can provide a useful mechanism for assessing the compatibility of a language with a given rhythm class by way of comparative analysis. This study therefore presents a durational-metric comparison of Scottish Gaelic, a language which has frequently been described as stress-timed but has never been empirically tested for rhythm class, with English, a prototypical and well-studied example of a stress-timed language. The Gaelic metric scores for %V (percentage of vocalic content), ΔV (standard deviation in vocalic interval length), and ΔC (standard deviation in consonantal interval length) (Ramus et al. 1999) are shown to be very similar to those measured for English, indicating that the language displays similar patterns of durational variability and segmental proportion typically ascribed to a rhythmically stress-timed language. This provides clear support for the classification of Scottish Gaelic as stress-timed.Dissertation/Thesis
Masters Thesis Linguistics and Applied Linguistics 2020