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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.
351

Patienters erfarenheter av tvångsvård inom den psykiatriska slutenvården : En beskrivande litteraturstudie

Bergh, Amanda, Sievers, Alexandra January 2019 (has links)
Sammanfattning Bakgrund: Inom den psykiatriska slutenvården i Sverige vårdas cirka en av fem patienter mot sin vilja, enligt Lagen om psykiatrisk tvångsvård (LPT). Att lida av psykisk ohälsa och blivit utsatt för tvångsvård är en omvälvande livshändelse för patienter. Det är önskvärt att förbättra tvångsvården och minska förekomsten av tvångsåtgärder. För att kunna göra det, och för att som sjuksköterska kunna ge bästa möjliga omvårdnad, krävs en djupare förståelse för patienters erfarenheter av tvångsvård.   Syfte: Att beskriva patienters erfarenheter av tvångsvård inom den psykiatriska slutenvården. Metod: En beskrivande litteraturstudie baserad på 13 vetenskapliga, kvalitativa artiklar. Huvudresultat: Resultatet, som presenteras i fem kategorier, visade att många patienter hade liknande erfarenheter av tvångsvård. Tvångsvården i sig beskrevs inte sällan som rätt åtgärd för att skydda patienten eller andra, men många patienter upplevde att den utfördes på fel sätt. Negativa erfarenheter som nämndes var brist på information, kommunikation och delaktighet eller att bli bemött som en diagnos av personalen. Däremot beskrevs empatisk och hjälpsam personal, adekvat information om sjukdom och behandling, känslan av delaktighet och autonomi samt en trevlig yttre miljö och flexibla regler som positiva erfarenheter som gynnade tillfriskningsprocessen.  Slutsats: Patienter beskrev ofta både bra och dåliga erfarenheter av tvångsvård. För att kunna ge bästa möjliga omvårdnad och minimera risken för tvångsåtgärder är det viktigt att sjuksköterskan känner till och har förståelse för patienters erfarenheter av tvångsvård. Det kan minska patientens vårdlidande och främja återhämtningen. / Abstract Background:Within the psychiatric inpatient care in Sweden, about one in five patients are cared for against their will, according to the Act on Psychiatric Forcible Care (LPT). Suffering from mental illness and being subjected to obsessive-compulsive care is a life-changing event for patients. It is desirable to improve coercive care and reduce the incidence of coercive measures. To be able to do that, and to be able to provide the best possible care as a nurse, a deeper understanding of patients experience of coercion is required. Aim: To describe patients experiences of coercion in psychiatric inpatient care. Method: A descriptive literature review based on 13 scientific articles with a qualitative approach. Main results: The results were presented in five categories and showed that many patients have similar experiences of compulsive care. Coercion was often described as the right measure to protect the patient or others, but many patients felt that it was performed incorrectly. Negative experiences mentioned were lack of information and communication, not being able to participate in their own care or being treated as a diagnosis by the staff. However, responsive, empathetic and helpful staff, adequate information on illness and treatment, the sense of participation and autonomy as well as a pleasant external environment and flexible rules were described as positive experiences and favorable to the recovery process. Conclusion: Patients often described both good and bad experiences of compulsive care. In order to provide the best possible care, and to minimize the risk of coercive measures, it is important for the nurse to know and understand patients' experiences of compulsive care. Then the patients suffering can be reduced and their recovery can be promoted.
352

The bicipital groove as a landmark for reconstruction of complex proximal humeral fractures with hybrid double plate osteosynthesis: The bicipital groove as a landmark for reconstruction of complex proximalhumeral fractures with hybrid double plate osteosynthesis

Theopold, Jan, Marquaß, Bastian, Fakler, Johannes, Steinke, Hanno, Josten, Christoph, Hepp, Pierre January 2016 (has links)
Background: Complex proximal humerus fractures with metaphyseal comminution remain challenging regarding reduction and stability. In most fracture patterns the hard bone of the bicipital groove remains intact. In this case series, we describe a novel technique of hybrid double plate osteosynthesis of complex proximal humerus fractures with metaphyseal comminution. Methods: In randomly chosen shoulder specimens and synthetic bones, pilot studies for evaluation of the feasibility of the technique were performed. Between 4/2010 and 1/2012 10 patients underwent hybrid double plate osteosynthesis. Seven patients (4 male, 3 female, mean age was 50 years (range 27–73)) were available for retrospective analysis. Based on plain radiographs (anterior-posterior and axial view), the fractures were classified according to the Orthopaedic Trauma Association classification (OTA) and by descriptive means (head-split variant (HS), diaphyseal extension or comminution (DE)). Results: Follow-up radiographs demonstrated complete fracture healing in six patients and one incomplete avascular necrosis. None of the patients sustained loss of reduction. Three patients where reoperated. The medium, not adapted, Constant score was 80 Points (58–94). Patients subjective satisfaction was graded mean 3 (range: 0–6) in the visual analog scoring system (VAS). Conclusion: The technique of hybrid double plate osteosynthesis using the bicipital groove as anatomic landmark may re-establish shoulder function after complex proximal humerus fractures in two dimensions. Firstly the anatomy is restored due to a proper reduction based on intraoperative landmarks. Secondly additional support by the second plate may provide a higher stability in complex fractures with metaphyseal comminution.
353

Quantization Effects Analysis on Phase Noise and Implementation of ALL Digital Phase Locked-Loop

Shen, Jue January 2011 (has links)
With the advancement of CMOS process and fabrication, it has been a trend to maximize digital design while minimize analog correspondents in mixed-signal system designs. So is the case for PLL. PLL has always been a traditional mixed-signal system limited by analog part performance. Around 2000, there emerged ADPLL of which all the blocks besides oscillator are implemented in digital circuits. There have been successful examples in application of Bluetooth, and it is moving to improve results for application of WiMax and ad-hoc frequency hopping communication link. Based on the theoretic and measurement results of existing materials, ADPLL has shown advantages such as fast time-to-market, low area, low cost and better system integration; but it also showed disadvantages in frequency resolution and phase noise, etc. Also this new topic still opens questions in many researching points important to PLL such as tracking behavior and quantization effect. In this thesis, a non-linear phase domain model for all digital phase-locked loop (ADPLL) was established and validated. Based on that, we analyzed that ADPLL phase noise prediction derived from traditional linear quantization model became inaccurate in non-linear cases because its probability density of quantization error did not meet the premise assumption of linear model. The phenomena of bandwidth expansion and in-band phase noise decreasing peculiar to integer-N ADPLL were demonstrated and explained by matlab and verilog behavior level simulation test bench. The expression of threshold quantization step was defined and derived as the method to distinguish whether an integer-N ADPLL was in non-linear cases or not, and the results conformed to those of matlab simulation. A simplified approximation model for non-linear integer-N ADPLL with noise sources was established to predict in-band phase noise, and the trends of the results conformed to those of matlab simulation. Other basic analysis serving for the conclusions above covered: ADPLL loop dynamics, traditional linear theory and its quantitative limitations and numerical analysis of random number. Finally, a present measurement setup was demonstrated and the results were analyzed for future work.
354

A Study of Injection Locking in Optoelectronic Oscillator

Prakasha, Prarthana 30 September 2020 (has links)
The random fluctuations of signal phase of an oscillator limit the precision of time and frequency measurements. The noise and long-term stability of the system’s oscillator or clock is of major importance in applications such as optical and wireless communications, high-speed digital electronics, radar, and astronomy. The Optoelectronic Oscillator (OE Oscillator), a new class of time delay oscillator with promise as a low-phase noise source of microwave carriers, was introduced by Steve Yao and Lute Malek in 1996. The OE Oscillator combines into a closed loop an RF photonic link and an RF chain. The RF photonic link consists of a laser, electro-optic modulator, optical fibre delay line, and a photo-receiver that together provide an RF delay. An RF chain consists of one or more amplifiers and a RF resonator that together provide the sustaining amplification and the frequency selectivity necessary for single mode oscillation of the loop. The low loss of optical fibres enables the attainment of delays that correspond to optical fibre lengths of several kilometers. It is the long delay, unattainable in an all electronic implementations that is responsible for the superior phase noise performance of an OE Oscillator. In this thesis the fundamental principles of operation of an OE Oscillator are described and the principal sources of in-loop phase fluctuations that are responsible for phase-noise identified. This lays the ground for an exposition of the mechanism that describes the perturbation of a time delay oscillator by injection into the loop of a carrier that is detuned in frequency from the natural frequency of the oscillator. For sufficiently small detuning the oscillator can become phase locked to the injected carrier. The model presented in the thesis generalises the traditional Yao-Maleki and Leeson model to include all the important features that describe the injection locking dynamics of an OE Oscillator. In particular the common assumptions of single mode oscillation and weak injection are removed. This is important to correctly predict the effect of injection locking on the spurious peaks in the phase noise spectrum corresponding to the side-modes of a time delay oscillator. Simulation results are presented in order to validate the dynamics of the oscillator under injection and analytic results on the lock-in range and phase noise spectrum. A 10 GHz OE Oscillator with a single 5km delay line is used as an example in the simulation illustration.
355

From Body to Self - Towards a Socially Enacted Autonomy With Implications for Locked-in Syndrome and Schizophrenia

Kyselo, Miriam 04 November 2013 (has links)
Embodied approaches to cognition consider themselves as alternatives to a brain-bound view of cognition. They decisively emphasize that the brain is not the minimal basis for cognition, but that the body plays a crucial role as well. But what do we actually mean by “the body” and to what extent is it a necessary condition for cognition? Is bodily action equated with movement? Is the human body just a biological phenomenon? How is it related to the human self and sociality? This thesis explores these questions by confronting embodied cognitive science with Locked-in Syndrome (LIS), a case of global paralysis, which despite the lack of voluntarily bodily action seems to leave the patient cognitively intact. I suggest that LIS poses a challenge to embodied cognitive science putting into question our basic assumptions on what it means to be a human cognitive system. A body without movement and a self whose connection to the social sphere is radically impoverished – how can we make sense of this? LIS challenges the concepts by which we describe the structure and various dimensions of cognition and it invites us to make explicit the background epistemology and general perspective through which we relate the different aspects of cognition. First, I provide an overview of the philosophy of cognitive science, from the orthodox perspective up to recent embodied cognitive science. I then introduce and clarify the enactive approach, an integrative framework for cognitive science that also serves as the epistemological basis of this thesis. Based on the different states of LIS I formulate a challenge to embodied cognitive science and discuss how the sensorimotor, functionalist and phenomenological approach to embodiment account for it. The discussion casts doubt on the assumption that a body has mainly to do with movement and it reposes the question how tool-use figures in cognition. It also brings to attention the dimension of bodily subjectivity and raises a much-neglected issue in recent cognitive science: the role of the body in social interactions. I show that these approaches to embodiment entail restrictive or loose notions of the body and are not fully able to account for cognition in LIS. I formulate a proposal for an enactive concept of the body integrating aspects from the sensorimotor and phenomenological approach to the body. I defend the idea that the enactive approach is the best framework in embodied cognitive science to counter the challenge posed by LIS and BCI. However, since embodied cognitive science entails an individualistic perspective not fully taking into account that humans are embedded in a social environment the question how the body matters in social interaction can also not be resolved from an enactive perspective on the body. In the last part of this thesis I thus propose transcending the level of individual embodiment. I make suggestions for elaborating on the enactive notion for the cognitive system (autonomy) from a social perspective. I propose to conceive of human mind in terms of a network that is based on the enaction of social processes of distinction and participation. Based on this notion I show how we arrive at an understanding of the human cognitive system which could ultimately account for the basic challenge posited by LIS – the clarification and interrelation of the concepts of body, self and sociality. In the last chapter I provide support for the plausibility for this proposal by applying it to another empirical context, namely psychiatry. What we think about the nature of human mind sets the ground for our thinking about breakdowns and what happens in cases when it does not work. I explore possible implications of the concept of socially enacted human autonomy for mental disorders in general, and for schizophrenia in particular.
356

Contribution à l’étude des lasers à verrouillage de modes pour les applications en télécommunications / Mode locked lasers for telecom applications.

Akrout, Akram 16 December 2009 (has links)
Ce travail de thèse porte sur l’étude des lasers à verrouillage de modes à bâtonnets quantiques (MLL QD) sur le système de matériau InAs/InP en vue de leur utilisation pour les applications télécoms. Contrairement aux lasers à deux sections, nous exploitons, tout au long de cette thèse, le phénomène du mélange à quatre-ondes qui est à l’origine du verrouillage de modes dans ces structures. Une analyse du « chirp » des impulsions générées par ce type de lasers, ainsi qu’une étude théorique et expérimentale pour le compenser, ont été décrites. En particulier, nous démontrons la compensation du « chirp » linéaire par un filtrage et par une fibre présentant une dispersion adéquate. D’autre part, une compensation du « chirp » d’ordre supérieur est possible en utilisant une fibre à dispersion spécifique. Une étude a été consacrée à la gigue temporelle, un autre paramètre crucial pour la plupart des applications utilisant les MLLs QD. Dans une première étape, nous avons mis en œuvre une technique de mesure par cross-corrélation optique pour caractériser la gigue temporelle des MLLs à haute fréquence de répétition. Contrairement à la technique de mesure par analyse spectrale, celle-ci permet d’effectuer des mesures à des fréquences de répétitions supérieures à 50 GHz et sur une plage de fréquence allant de presque 0 Hz à quelques centaines de MHz. Ensuite, nous avons caractérisé des diodes lasers présentant une largeur de raie RF record d’une valeur de 850 Hz. Une valeur de gigue de 500 fs a été mesurée sur la bande de fréquence [150 kHz-320 MHz]. Cette valeur correspond à une amélioration d’un facteur 25 par rapport à la valeur mesurée sur une structure à base de puits quantiques pour les mêmes bornes d’intégration. Nous avons également présenté une étude de la réduction du bruit de phase des MLLs basée sur l’effet de la réinjection optique. Nous avons ainsi obtenu une amélioration du niveau de bruit de phase d’un facteur supérieur à 15 dB par rapport à la technique optoélectronique standard. Ces résultats mettent en évidence le potentiel des MLL QD pour la génération des impulsions à très faibles gigue temporelle et ouvrent la voie pour la conception des oscillateurs tout-optiques à faible bruit de phase. Enfin, nous présentons la génération d’un peigne de fréquences WDM en utilisant un MLL QD. En utilisant une telle source, nous avons démontré une transmission canal par canal sur une distance de 50 km de fibre SMF à un débit de 10 Gbit/s. Ce résultat de toute première importance permet d’envisager l’utilisation des MLLs QD pour la transmission WDM / This PhD thesis deals with the integration of InP based quantum dash mode locked lasers for use in optical communication systems and microwave optoelectronic applications. The properties of pulse and characterization methods are described as well as requirements for application in communication systems. Experimental and analytic method for pulse “chirp” characterization and compensation are also discussed. In particular, we demonstrate that high order dispersion can be compensated using specific fibre length. The characterization of quantum dash based mode locked lasers, has shown their potential to generate high spectral purity self-pulsating signals, with state-of-the-art spectral linewidth of ~ 850 Hz. Especially, the importance of, and way to reduce high-frequency jitter is discussed. Indeed, a novel method for measurement of high-frequency jitter based on optical cross-correlation technique is implemented. Systematic investigation of 10 GHz passively mode locked laser based on InAs/InP quantum dashes emitting at 1.55 µm have demonstrated a reduced value of timing jitter of 500 fs in the 150 kHz – 320 MHz frequency range. Compared to typical passively mode-locked quantum well laser which exhibit timing jitter in the range 12 ps (150 kHz – 50 MHz), our device demonstrates an approximately 25 times improvement in timing jitter. Concerning microwave optoelectronic applications, we demonstrate that a low phase noise oscillator can be obtained using a QD MLL integrated in an optical self injection loop without any opto-electronic or electro-optic conversion. A significant reduction of the -3 dB linewedith as low as 200Hz was obtained thanks to optimised tuning of the optical external cavity length. The phase noise has been reduced from -75dBc/Hz to a level as low as -105dBc/Hz at an offset of 100kHz. This yields to ultra low timing jitter and shows the potential to fabricate simple, and yet low noise oscillators based on semiconductor lasers without any high frequency electronics, photodetector or modulator. Finally, we report, for the first time, error-free transmission of 8 WDM channels over 50 km long single mode fiber at 10 Gbit/s using comb-generation in a quantum dash based mode locked laser. Such good performance paves the way for the use of mode locked-lasers in WDM transmission and allows considering such a solution in an integrated WDM transceiver
357

Modélisation, conception et intégration de nouvelles architectures différentielles pour des capteurs M/NEMS résonants / Modelling, design and integration of new differential architectures for M/NEMS resonant sensors

Prache, Pierre 09 November 2017 (has links)
Les capteurs M/NEMS résonants, grâce à leur petite taille, faible consommation, et caractère quasi-numérique (leur grandeur de sortie est une fréquence la plupart du temps), sont des outils incontournables dans les systèmes embarqués modernes, des objets connectés simples à l’industrie aérospatiale et militaire.Cependant, ils sont soumis aux dérives environnementales, et malgré la possibilité d’en diminuer l’effet par différentes techniques de conception, parfois l’association de deux capteurs en mode différentiel est nécessaire pour assurer la fiabilité de l’information en environnement difficiles. Dans cette thèse, une technique particulière de mesure différentielle est étudiée, qui consiste à synchroniser deux résonateurs, dont l’un est une référence et l’autre soumis à la grandeur physique à mesurer. Placés dans une seule boucle de rétroaction, les deux résonateurs oscillent à la même fréquence, et un désaccord entre les deux, issu de la grandeurphysique à mesurer entraine un déphasage. La mesure de ce déphasage est un moyen simple de remonter à l’information à mesurer, théoriquement insensible aux variations environnementales identiquement appliquées aux deux résonateurs. Cette technique bénéficie est également peu complexe au niveau de son implémentation, donc adapté à l’intégration à grande échelle. Après avoir étudié le cadre théorique de la synchronisation de résonateurs par verrouillage par injection, on dégage des contraintes d’implémentation, qui servent de ligne directrice dans la fabrication d’un démonstrateur. On dégage également des performances théoriques, qui sont comparées aux performances du démonstrateur. / M/NEMS resonant sensors, due to their small size, consumption and quasi-digital output (a frequency most of the time) are unavoidable tools for on-board systems, from smartphones to aeronautic technology. However, they suffer from environmental drifts, and even though the effect of these drifts can be limited by the design, it is sometimes necessary to use differential architectures to properly remove the drifts from the measurements and ensure the output reliability even in harsh environments. In this work, a special technique for differential measurement is studied, consisting in the synchronization of two resonators, one reference and one sensor. Placed in a single feedback loop, they oscillate at the same frequency and eventual phase shift when the physical quantity to be sensed is applied. This phase shift is a theoretically drift-free way to measure this physical quantity. This technique also benefits from its ease of integration, making it a good candidate for large scale integration. After studying the theoretical framework, several design guidelines are found, which are used in the fabrication of a proof of concept. The theoretical performances are found as well, and compared to the experimental ones.
358

Product development of Dosis locked daily pill box / Produktutveckling av Dos - en låst pillerbox för dagligt bruk

Venkatachala, Jayanth January 2019 (has links)
Taking medication at the prescribed times is very important for people with mental issues like schizophrenia, dementia Alzheimer’s and depression. But their condition itself keeps them from doing so. They are either forgetful or choose not to take the pills intentionally. This could lead to missing dosage or overdosing both of which are dangerous to the person’s health. Hence a pill box that monitors the dosage and keeps them from being able to access the pills at undesired times is needed. The aim of the thesis is to design such a pill box for the company Victrix AB in Stockholm, Sweden, by expanding on their current pill box, Dosis. In the project, the locking mechanism to keep the lids closed was rigorously designed in phases after understanding the user conditions. The end result is a locked daily pill box that is ergonomic to use for people of all ages, mental and physical conditions. The product sets itself apart from its competitors by being compact, less medical looking and very easy to use. / Att ta mediciner vid föreskrivna tidpunkter är mycket viktigt för personer med psykiska problem som schizofreni, alzheimers, demens och depressioner. Dock kan deras tillstånd hindra dem från att göra det. De är antingen glömska eller så väljer de att inte ta medicinen avsiktligt. Sådant beteende kan leda till saknad dosering eller överdosering, vilka båda är farliga för personens hälsa. Därmed behövs en pillerask som övervakar doseringen och hindrar dem från att komma åt pillerna vid oönskade tidpunkter. Syftet med examensarbetet har varit att designa en sådan pillerask för företaget Victrix AB i Stockholm, Sverige, genom att utöka sin nuvarande ask, Dosis. I projektet designades låsmekanismen noggrant i faser, genom en ökad förståelse av användarförhållandena, för att hålla locken stängda,. Slutresultatet blev en låst daglig pillerask som är ergonomisk för personer i olika åldrar med mentala och fykiska problem. Produkten skiljer sig från dess konkurrenter genom att vara kompact, inte ha ett typiskt medicinskt utseende samt mycket enkel att använda.
359

Synchronization In Advanced Optical Communications

Kim, Inwoong 01 January 2006 (has links)
The objective of this dissertation is to generate high power ultrashort optical pulses from an all-semiconductor mode-locked laser system. The limitations of semiconductor optical amplifier in high energy, ultrashort pulse amplification are reviewed. A method to overcome the fundamental limit of small stored energy inside semiconductor optical amplifier called "eXtreme Chirped Pulse Amplification (X-CPA)" is proposed and studied theoretically and experimentally. The key benefits of the concept of X-CPA are addressed. Based on theoretical and experimental study, an all-semiconductor mode-locked X-CPA system consisting of a mode-locked master oscillator, an optical pulse pre-stretcher, a semiconductor optical amplifier (SOA) pulse picker, an extreme pulse stretcher/compressor, cascaded optical amplifiers, and a bulk grating compressor is successfully demonstrated and generates >kW record peak power. A potential candidate for generating high average power from an X-CPA system, novel grating coupled surface emitting semiconductor laser (GCSEL) devices, are studied experimentally. The first demonstration of mode-locking with GCSELs and associated amplification characteristics of grating coupled surface emitting SOAs will be presented. In an effort to go beyond the record setting results of the X-CPA system, a passive optical cavity amplification technique in conjunction with the X-CPA system is constructed, and studied experimentally and theoretically.
360

A Laser Radar Employing Linearly Chirped Pulses From A Mode-locked Laser For Long Range, Unambiguous, Sub-millimeter Resolution Ranging And Velocimetry

Piracha, Mohammad Umar 01 January 2012 (has links)
Light detection and ranging (lidar) is used for various applications such as remote sensing, altimetry and imaging. In this talk, a linearly chirped pulse source is introduced that generates wavelength-swept pulses exhibiting ~6 nm optical bandwidth with > 20 km coherence length. The chirped pulses are used in an interferometric lidar setup to perform distance measurements with sub-millimeter resolution (using pulses that are a few meters long), at target distances > 10 km, with at least 25 dB signal-to-noise ratio at the receiver. A pulse repetition rate of 20 MHz provides fast update rates, while chirped pulse amplification allows easy amplification of optical signals to high power levels that are required for long range operation. A pulse tagging scheme based on phase modulation is used to demonstrate unambiguous, long range measurements. In addition to this, simultaneous measurement of target range and Doppler velocity is performed using a target moving at a speed of over 330 km/h (205 mph) inside the laboratory. In addition to this, spectral phase modulation of the chirped pulses is demonstrated to compensate for the undesirable ripple in the group delay of the chirped pulses. Moreover, spectral amplitude modulation is used to generate pulses with Gaussian temporal intensity profiles and a two-fold increase in the lidar range resolution (284 um) is observed.

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