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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Tidig elit? : En kvantitativ studie om eleverna på Sveriges elitinnebandygymnasier

Hargesson, Markus, Ljungholm, Tobias January 2011 (has links)
Syfte och frågeställningar: Studiens huvudsakliga syfte var att undersöka vilka elever som går på Sveriges elitinnebandygymnasier efter reformen av den gymnasiala idrottsutbildningen.Ytterligare ett syfte var att urskilja påverkansfaktorer i utvecklingsprocessen som innebandyspelare.- Hur ser förekomsten av relative age effect ut på elevpopulationen?- Hur upplever eleverna sina förväntningar och egna förmåga i sitt innebandyutövande?- Hur ser elevernas idrottsbakgrund ut? Metod: Enkätundersökning har använts som metod i denna studie. Totalt har 132 elever på Sveriges elitinnebandygymnasier besvarat enkäten. Könsfördelningen var 46 flickor och 86 pojkar. Enkäten bestod av både öppna och slutna frågor där eleverna fick besvara frågor som rörde deras idrottande idag samt idrottsbakgrund. Resultat: Elevernas födelsefördelning var spridd sett till hela populationen. Bland pojkarna på Riksidrottsgymnasiet var 58 % födda under det första kvartalet och visade på en relative age effect. Majoriteten av eleverna började spela innebandy i tidig ålder, innan nio års ålder. Utöver innebandy hade över 90 % av eleverna sysslat med flera andra idrotter under sin uppväxt, men de flesta hade nu specialiserat sig på innebandy. Bland eleverna strävade 94 % mot elitnivå, majoriteten tränade innebandy mellan 7-12 timmar/vecka. Pojkarna tränade, i större utsträckning, mer än flickorna. En stor majoritet bland flickorna och ungefär 60 % bland pojkarna hade deltagit i SDF-SM för femtonåringar. Eleverna angav att de hade höga krav på sig själva som generellt var högre än de krav de upplevde utifrån. Det var en stor spridning på hur eleverna uppfattade sin egen förmåga jämfört med sina lagkamrater. Det var dock väldigt ovanligt att eleverna inte alls tyckte sig tillhöra, eller att de tidigare tillhört, de bästa i laget. Slutsats: Den nya gymnasiereformen har påverkat idrottsutbildningarna där en intensifierad elitsatsning införts. Denna studie fokuserade på innebandygymnasierna och vi kan konstatera att eleverna delade utbildningens elitambition. Vad de långsiktiga effekterna kommer bli är omöjligt att säga men säkert är att den elitistiska inriktningen på ett eller annat sätt kommer påverka eleverna. Forskningen är fortfarande tudelad om vilka effekter en tidig elitsatsning har och om vilken väg som är den bästa för framtidens elitspelare. Efter att ha genomfört denna studie kunde vi konstatera att majoriteten av eleverna har en bred idrottsbakgrund och relativt sent specialiserat sig på en idrott.
42

Automated Spacecraft Docking Using a Vision-Based Relative Navigation Sensor

Morris, Jeffery C. 14 January 2010 (has links)
Automated spacecraft docking is a concept of operations with several important potential applications. One application that has received a great deal of attention recently is that of an automated docking capable unmanned re-supply spacecraft. In addition to being useful for re-supplying orbiting space stations, automated shuttles would also greatly facilitate the manned exploration of nearby space objects, including the Moon, near-Earth asteroids, or Mars. These vehicles would allow for longer duration human missions than otherwise possible and could even accelerate human colonization of other worlds. This thesis develops an optimal docking controller for an automated docking capable spacecraft. An innovative vision-based relative navigation system called VisNav is used to provide real-time relative position and orientation estimates, while a Kalman post-filter generates relative velocity and angular rate estimates from the VisNav output. The controller's performance robustness is evaluated in a closed-loop automated spacecraft docking simulation of a scenario in circular lunar orbit. The simulation uses realistic dynamical models of the two vehicles, both based on the European Automated Transfer Vehicle. A high-fidelity model of the VisNav sensor adds realism to the simulated relative navigation measurements. The docking controller's performance is evaluated in the presence of measurement noise, with the cases of sensor noise only, vehicle mass errors plus sensor noise, errors in vehicle moments of inertia plus sensor noise, initial starting position errors plus sensor noise, and initial relative attitude errors plus sensor noise each being considered. It was found that for the chosen cases and docking scenario, the final controller was robust to both types of mass property modeling errors, as well as both types of initial condition modeling errors, even in the presence of sensor noise. The VisNav system was found to perform satisfactorily in all test cases, with excellent estimate error convergence characteristics for the scenario considered. These results demonstrate preliminary feasibility of the presented docking system, including VisNav, for space-based automated docking applications.
43

Observational Learning of a Bimanual Coordination Task: Understanding Movement Feature Extraction, Model Performance Level, and Perspective Angle

Dean, Noah J. 2009 December 1900 (has links)
One experiment was adminstered to address three issues central to identifying the processes that underlie our ability to learn through observation. One objective of the study was to identify the movement features (relative or absolute) extracted by an observer when demonstration acts as the training protocol. A second objective was to investigate how the performance level of the model (trial-to-trial variability in strategy selection) providing the demonstrations influences movement feature extraction. Lastly, a goal was to test whether or not visual perspective of the model by the observer (first-person or third-person) interacts with the aforementioned variables. The goal of the task was to trace two circles templates with a 90 degree relative phase offset between the two hands. Video recordings of two models practicing over three days were used to make three videos for the study; an expert performance, discovery performance, and instruction performance video. The discovery video portrayed a decrease in relative phase error and a transition from high trial-to-trial variability in the strategy selection to use of a single strategy. The instruction video also portrayed a decrease in relative phase error, but with no strategy search throughout practice. The expert video showed no strategy search with trial-to-trial variability within 5% of the goal relative phase of 90 across every trial. Observers watched one of the three video recordings from either a first-person or third-person perspective. In a retention test, the expert observers showed the most consistant capability (learning) in performing the goal phase. The instruction observers also showed learning, but to a lesser degree than the expert observers. The discovery group observers showed the least amount of learning of relative phase. The absolute feature of movement amplitude was not extracted by any observer group, results consistent with postulations by Scully and Newell (1985). Observation from the 1P perspective proved optimal in the expert and instruction observation groups, but the 3P perspective allowed for greater learning of of the goal relative phase (90 degree) in the discovery observation group. Hand lead, a relative feature of motion, was extracted by most obsevers, except those who observed the discovery model from the 3P perspective. It's concluded that the trial-to-trial variabiliy in terms of strategy selection interacted with the process of mental rotation, which prevented the extraction of hand lead in those observers that viewed the discovery model.
44

Perceptual and Attentional Constraints on 1:1 Bimanual Coordination

Kovacs, Attila J. 2010 May 1900 (has links)
Two experiments were conducted in an attempt to further the understanding of how previously identified intrinsic constraints and perceptual factors interact in influencing the learning and performance of various bimanual coordination patterns. The purpose of Experiment 1 was to determine the influence of Lissajous feedback on 1:1 bimanual coordination patterns (0°, 90°, 180° phase lags) when the movement amplitudes of the two limbs were different. Participants coordinated rhythmic movements of their forearms while being provided separate feedback for each limb (no- Lissajous group) or integrated feedback (Lissajous group). Data from Experiment 1 supports the notion that the lead-lag relationship as well as amplitude assimilation between limbs observed in the literature can be partially attributed to the visualperceptual factors present in the testing environment. When participants are provided integrated feedback in the form of Lissajous plots and templates much of the lead-lag and amplitude assimilation effects were eliminated and relative phase error and variability were also greatly reduced after only 3 min of practice under each condition. Results from recent experiments suggest that when the salient visual information (Lissajous feedback) is removed, performance in bimanual coordination tasks rapidly deteriorates. The purpose of Experiment 2 was to determine if reducing the frequency of feedback presentation will decrease the reliance on the feedback and will facilitate the development of an internal representation that will improve performance when visual feedback is removed. Participants receiving reduced frequency feedback presentation were able to perform a delayed retention test with the feedback removed as well as the test with feedback present. Data from Experiment 2 demonstrates that salient extrinsic Lissajous feedback can effectively be combined with reduced frequency feedback presentation in a way that performance levels, when tested without the availability of feedback, match those obtained when tested in the presence of Lissajous feedback. Taken together the present experiments add to the growing literature that supports the notion that salient perceptual information can override some aspects of the system's intrinsic dynamics typically linked to motor output control. The strong tendencies toward the intrinsic dynamics found in numerous previous bimanual movement studies and the difficulties in producing various coordination patterns may actually represent detrimental effects attributable to the perceptual information available in the environment and the attentional focus participants adopt. Given external integrated salient visual information participants can essentially tune-in and learn difficult bimanual coordination patterns with relatively little practice.
45

Application of Data Envelopment Analysis to Evaluate Efficiency of Nursing Units: Sample of Two Medical Centers

Au, Wai-Yung 27 August 2003 (has links)
In the recent years most of the studies related to the hospital efficiency focus on the issues of the ownership, size, physician team work, and clinical performance. It is certain that nursing units are the major profit centers for hospitals. However, the relative efficiency of nursing units regarding the resource use and outputs is seldom investigated. Therefore the aim of this study is to investigate the influence of each input and output item on the relative efficiency using Data Envelopment Analysis (DEA). The research samples included 44 units of two government owned hospital accredited as medical centers in 2002. The research samples are divided into 5 groups. The inputs items include full time nurse, continuous education hours, cost expand, specialties, patient care hours and workload. The output items are length of stay, number of admission, occupancy rate and total patient days. Every nursing unit is considered as a Decision Making Unit (DMU). The data were collected from Jan. to Dec. 2002 to evaluate the overall efficiency, technical efficiency and scale efficiency. Efficiency reference sets were found to be reference for inefficiency nursing units. The ways to improve the resources inputs or outputs of those inefficient nursing units were suggested using scale variable analysis. The influence of each input and output variable on the relative efficiency were assessed using sensitivity analysis. The results are summarized as follows:. 1. Overall inefficiency nursing units: A hospital has 4 (20%), B hospital has 5 (20%), both A and B hospitals have 9 (21%), medical nursing units have 5(17%)and surgical nursing units have 7 (47%). 2. Technical inefficiency nursing units: A hospital has 2 (10%), B hospital has 2 (8%), both A and B hospital have 3(6%), medical nursing units has one (3%)and surgical nursing units have 4(27%). 3. Scale inefficiency nursing units: A hospital has 4(20%), B hospital has 5 (20%), both A and B hospital have 9 (21%), medical nursing units have 5 (17%)and surgical nursing units have 7(47%). 4. Relative inefficiency nursing units with overall efficiency value between 0.9-1 belong to the marginal inefficiency units. The overall inefficiency of nursing units due to scale inefficiency. 5. From slack variable analysis the first three inputs needed to reduced are continue education hours, patient care hours and number of full time nurse. The outputs needed to increase are the number of admission and the length of stay. In this study, the input items to evaluate the efficiency of nursing units are mainly based on the data of clinical productivity. However, the quality of nursing care, the index of patient satisfaction, the number of medical equipments and the standard on patient care activities are not considered. It is highly suggested that service index and equipment allocation should be considered while evaluating efficiency.
46

Dynamics and control of satellite relative motion in a central gravitational field

Sengupta, Prasenjit 25 April 2007 (has links)
The study of satellite relative motion has been of great historic interest, primarily due to its application to rendezvous, intercept, and docking maneuvers, between spacecraft in orbit about gravitational bodies, such as the Earth. Recent interest in the problem of satellite formation flight has also led to renewed effort in understanding the dynamics of relative motion. Satellite formations have been proposed for various tasks, such as deep-space interferometry, and terrestrial observation, among others. Oftentimes, the rich natural dynamics of the relative motion problem near a gravitational body are exploited to design formations of a specific geometry. Traditional analysis models relative motion under the assumptions of a circular reference orbit, linearized differential gravity field (small relative distance), and without environmental perturbations such as oblateness effects of the attracting body, and atmospheric drag. In this dissertation, the dynamics of the relative motion problem are studied when these assumptions are relaxed collectively. Consequently, the combined effects of nonlinearity, eccentricity, and Earth oblateness effects on relative motion, are studied. To this end, coupling effects between the various environmental perturbations are also accounted for. Five key problems are addressed - the development of a state transition matrix that accounts for eccentricity, nonlinearity, and oblateness effects; oblateness effects on averaged relative motion; eccentricity effects on formation design and planning; new analytical expressions for periodic relative motion that account for nonlinearity and eccentricity effects; and a solution to the optimal rendezvous problem near an eccentric orbit. The most notable feature of this dissertation, is that the solutions to the stated problems are completely analytical, and closed-form in nature. Use has been made of a generalized reversion of vector series, and several integral forms of Kepler’s equations, without any assumptions on the magnitude of the eccentricity of the reference orbit.
47

De la responsabilité des compagnies en matière de transports internationaux de marchandises les conventions de Berne /

Four, Charles. January 2006 (has links)
Reproduction de : Thèse doctorat : Droit : Lyon : 1931. / Titre provenant de l'écran-titre. Notes bibliogr. p. [127]-128.
48

Upplevelser av att leva som anhörig till en person med demenssjukdom : En litteraturstudie

Classon, Olivia, Skogsberg, Hanna January 2015 (has links)
Bakgrund: Idag lever 47,5 miljoner människor med demenssjukdom och den siffran beräknas bli fördubblad var 20e år. Sjukdomen medför stora förändringar i den drabbades och den anhörigas liv och kallas ofta för “De anhörigas sjukdom”. De anhöriga har en viktig roll i den demenssjukes liv, eftersom han eller hon ofta har levt en större del av livet tillsammans med personen med demenssjukdom. Det är därför den anhöriga som känner den drabbade bäst, trots att sjukdomen leder till personlighetsförändringar. Syfte: Att beskriva upplevelser av att leva som anhörig till en person med demenssjukdom (PMD), samt att beskriva hur urvalsgrupperna i de ingående artiklarna ser ut. Metod: En litteraturstudie med deskriptiv design baserad på 12 kvalitativa vetenskapliga artiklar som framkom efter sökningar i databaserna PubMed och CINAHL. Materialet bearbetades och delades in i ämnesrubriker. Huvudresultat: Resultatet visade att anhöriga till PMD ofta upplevde känslor av frustation, oro samt skuldkänslor på grund av bristande information och kommunikation. De anhöriga beskrev också hur de upplevde anpassningen till de förändringar som skett i deras och PMDs liv och på vilka sätt de hanterade förändringarna. Slutsats: De upplevda känslor som framkom i resultatet kom ofta av förlorad kontroll och förändringar som var svåra för de anhöriga att anpassa sig till. Brist på förtroende, dålig kommunikation och otillräcklig information var orsaker till den bristande tilliten. Genom att främja en god relation mellan sjuksköterska och de anhöriga, kan de anhöriga uppleva tillit och trygghet. Det i sin tur kan bidra till att vårdsituationen blir så bra som möjligt för alla inblandade parter. / Background: 47.5 million people live with dementia today, and this number is expected to double every 20 year. This disease causes big changes for the person who suffers and the relative’s life and is often called "The relatives' disease". The relatives have an important role in the dementia sufferer's life, because he or she often has lived a large part of their life with the person with dementia, it is the relatives who know them the best, even though the disease leads to personality changes. Aim: To describe the experiences of living as a relative to a person with dementia (PWD) and to describe the study group in the included articles. Method: A literature study based on twelve qualitative scientific studies that was found through searches in the two databases PubMed and CINAHL. The material was processed and divided into content areas. Main results: The result showed that relatives of PWD often experienced feelings of frustration, anxiety and guilt due to lack of information and communication. They also described how they experienced the adaptation to the changes in their and the PWD lives and the ways in which they managed those changes. Conclusion: The perceived feelings that emerged in the results often came of loss of control and the changes that were difficult for the families to adapt to. Lack of confidence, poor communication and inadequate information were reasons for the lack of trust. By developing a good relationship between the nurse and the families, the families can experience trust and security. That in turn could help the care situations to be as good as possible for all involved parties.
49

Grammar and Parsing: A Typological Investigation of Relative-Clause Processing

Lin, Chien-Jer Charles January 2006 (has links)
This dissertation investigates the role of grammar and parsing in processing relative clauses across languages. A parsing theory called the Incremental Minimalist Parser (IMP), which parses sentences incrementally from left to right, is sketched based on the Minimalist Program (Chomsky, 2001, 2005). We provide sentence processing evidence which supported a universal parsing theory that is structure-based. According to IMP (and other structure-based theories), a gap located at the subject position is more easily accessed than a gap located at the object position in both head-initial (e.g. English) and head-final (e.g. Mandarin) relative clauses. Experiment 1 (self-paced reading tasks) showed a processing advantage for Mandarin relative clauses that involved subject extractions over object extractions, consistent with the universal subject preference found in all other languages. Experiments 2 to 4 (naturalness ratings, paraphrasing tasks, and self-paced reading tasks) focused on possessor relative clauses. When the possessor gap was located at the subject position (i.e. in passives), a possessive relation was easier to construct than when the gap was located at an object position (i.e. in canonical constructions and sentences involving BA). The results of Experiments 1-4 suggested that processing accounts based on locality and canonicity, but not on syntactic structure, cannot account for the processing preferences of filler-gap relations in relative clauses. Experiment 5 (self-paced reading tasks) investigated whether the surface NVN sequence of relative clauses at sentence-initial positions induced garden path, and whether the animacy of the first noun in such sequences could rescue the garden path. Mandarin relative clauses involving topicalization of the embedded object were investigated. The results suggested that the surface NVN sequence did induce main-clause misanalysis (as Subject-Verb-Object). Even when the first noun was (semantically) an unlikely agent, the parser took it as a subject in the initial syntactic analysis. Semantics did not have an immediate effect on syntactic processing.
50

The Syntax, Processing and Second Language Acquisition of Chinese Relative Clauses

Xu, Yi January 2009 (has links)
The structural complexity and the typological universals associated with relative clauses (RCs) have made the structure particularly interesting to linguists and second language acquisition (SLA) researchers. Currently, much controversy is found in RCs in East Asian Languages. This dissertation tests the syntactic status of "relative clauses" in Chinese and explores second language (L2) learners' processing and production of different types of Chinese RCs.In the theoretical part of the dissertation, I test whether Comrie (2002)'s proposal of analyzing putative relative clauses in East Asian languages as "attributive clauses" can be applicable to Chinese. From a review of syntactic literature and movement test, I argue that there are crucial differences between Chinese RCs and attributive clauses. Further, reconstruction effect suggests that A-bar movement takes place within gapped Chinese RCs. More specifically, following Sauerland (2000)'s proposal, I suggest that the derivation of Chinese RCs involves the movement of an operator taking a complex NP as its complement to the Spec of CP, and that complex NP matches with an external head outside the RC.Further, I examine the possibility of analyzing AdjP+DE structure as relative clauses, and examine the flexibility and effect of demonstrative and numeral-classifier positions and their relation with relative clauses.In the experiment chapter, I discuss results from three experiments that tested the relative degrees of difficulty for L2 learners among different types of RCs including Subject, Direct Object, Indirect Object and Object of Preposition relative clauses, I seek plausible linguistic and psycholinguistic proposals in explaining the performance data. The experiments include a self-paced word order judgment task, a written sentence completion task, and a written sentence combination task. It was found that the L2 acquisition of Chinese RCs is generally consistent with the Noun Phrase Accessibility Hierarchy (Keenan & Comrie, 1977), a typological generalization based on natural languages and a hierarchy that was found to be predictive of learners' order of acquisition in SLA studies of many other languages.

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