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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.
481

Hälsorelaterad livskvalitet hos hjärt-kärlsjuka individer / Healt-related quality of life among individuals with cardiovascular diseases

Göransson, Emilia, Uhre Grönqvist, Eveline January 2012 (has links)
Bakgrund: I Sverige lever cirka 1,1 miljoner individer med en hjärt-kärlsjukdom. Hjärt-kärlsjuka individer skattar sin hälsorelaterade livskvalitet lägre än normalbefolkningen och lågt skattad hälsorelaterad livskvalitet kan medföra fler inläggningar på sjukhus samt en ökad risk att avlida i sin hjärt- kärlsjukdom. Syfte: Syftet med studien var att beskriva hälsorelaterad livskvalitet hos hjärt- kärlsjuka individer och hur kön, ålder, tobaksanvändning, graden av fysisk aktivitet, eller samtida sjukdom påverkar den hälsorelaterade livskvaliteten. Metod: Empirisk, deskriptiv tvärsnittsstudie med kvantitativ ansats. Valt mätinstrument var Short-Form 36 (SF-36), skala 0-100 där ett högre värde motsvarar en högre skattad hälsorelaterad livskvalitet. Databearbetning genomfördes med deskriptiv och analyserande statistik där SF-36 testades mot kön, ålder, tobaksvanor, graden av fysisk aktivitet, eller samtida sjukdom. Resultat: Totalt inkluderades 53 hjärt- kärlsjuka individer, varav 28 var män. Medelåldern i gruppen var 69,5 år (SD 11,9 år). Samtida sjukdomar var den bakgrundsvariabel som påverkade skattningen av hälsorelaterad livskvalitet mest, men även kön, grad av fysisk aktivitet och ålder påverkar skattningen av hälsorelaterad livskvalitet. Tobaksanvändning påverkade inte den hälsorelaterade livskvaliteten. Konklusion: Denna studie visar att omvårdnadsåtgärder bör inriktas hos hjärt- kärlsjuka individer med annan samtida sjukdom. Sjuksköterskan bör även identifiera grad av fysisk aktivitet, ålder och kön för att på så sätt arbeta preventivt mot en förbättrad hälsorelaterad livskvalitet.
482

Accuracy Improvement of Closed-Form TDOA Location Methods Using IMM Algorithm

Chen, Guan-Ru 31 August 2010 (has links)
For target location and tracking in wireless communication systems, mobile target positioning and tracking play an important role. Since multi-sensor system can be used as an efficient solution to target positioning process, more accurate target location estimation and tracking results can be obtained. However, both the deployment of designed multi-sensor and location algorithm may affect the overall performance of position location. In this thesis, based on the time difference of arrival (TDOA), two closed-form least-square location methods, spherical-interpolation (SI) method and spherical-intersection (SX) method are used to estimate the target location. The two location methods are different from the usual process of iterative and nonlinear minimization. The locations of the target and the designed multiple sensors may yield geometric effects on location performance. The constraints and performance of the two location methods will first be introduced. To achieve real-time target tracking, the Kalman filtering structures are used to combine the SI and SX methods. Because these two positioning and tracking systems have different and complementary performance inside and outside the multi-sensor array, we consider using data fusion to improve location estimation results by using interacting multiple model (IMM) based estimator, in which internal filters running in parallel are designed as the SX-KF1 and the SI-KF2. However, due to the time-varying characteristics of measurement noises, we propose an adjusting scheme for measurement noise variance assignment in the Kalman filters to obtain improved location estimation results. Simulation results are obtained by running Matlab program. In three-dimensional multi-sensor array scenarios, the results of moving target location estimation shows that the IMM-based estimators effectively improve the position performance.
483

Design of Adaptive Block Backstepping Controllers for Nonlinear Systems with Non-strict Feedback Form

Chien, An-fu 09 November 2010 (has links)
Based on the Lyapunov stability theorem, two design methodologies of adaptive block backstepping controller is proposed in this thesis for a class of multi-input systems with matched and mismatched perturbations to solve regulation problems. The main difference between these two method is that perturbation estimations are only employed in each virtual control input in the second method, whereas in the first method, the perturbation estimation is only employed in the last block. According to the number of block (m) in the dynamic equations of plant to be controlled, m-1 virtual input controllers are designed from the first block to the (m-1)th block, and the proposed robust controller is designed from the last block. Adaptive mechanisms are employed in each of the virtual input controllers as well as the robust controller, so that the least upper bounds of perturbations and perturbation estimation errors are not required. Furthermore, the dynamic equations of the plant do not need to satisfy the block strict feedback form, and the resultant control system can achieve asymptotic stability or uniformly ultimately boundedness. Finally, a numerical example and a practical example are given for demonstrating the feasibility of the proposed control schemes.
484

Evaluation of zirconium-iron-rhenium alloys as surrogates for a technetium alloy waste form

Mews, Paul Aaron 15 May 2009 (has links)
Stainless steel – zirconium alloys were developed by the US Department of Energy Laboratories as metallic waste forms for noble metal fission products. This thesis evaluates iron–zirconium–rhenium alloys to establish a technical basis for using metal waste form alloys for technetium-99 immobilization. Rhenium is used as a surrogate for Tc-99 since Tc is not naturally available and Re is metallurgically similar to Tc. The iron-zirconium system has two eutectic compositions, Fe-15 wt % Zr and Zr- 16 wt% Fe. Ten test samples were successfully cast in yttrium oxide crucibles at 1600°C, half near each eutectic composition, with Re amounts varying from 2.5 to 12.5 weight percent. A scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDS) capability was employed to determine the phase structure and phase composition of each sample. Iron rich samples were found to form up to three phases, with the rhenium content favoring the intermetallic phases: 1) an Fe solid solution phase, 2) an FeZr2-type intermetallic with 11 wt % or less Re, and 3) a second intermetallic with about 18 wt % Re. Zirconium rich samples formed as many as five distinct phases: 1) a Zr solid solution phase, 2) a Zr3Fe-type intermetallic with as much as 13 wt% Re, 3) a rhenium-zirconium intermetallic, 4) another Fe-Zr intermetallic with very little Re, and 5) a Fe-Re intermetallic. Potentiostatic and potentiodynamic electrochemical tests were performed using sulfuric acid to evaluate the corrosion resistance of each sample. These tests found that the zirconium rich samples were very corrosion resistant but became increasingly susceptible at higher rhenium concentrations. The iron rich samples were not very resistant to corrosion under the test conditions; there was no notable trend in corrosion behavior related to the introduction of rhenium.
485

Single Inductor Dual Output Buck Converter

Eachempatti, Haritha 2009 May 1900 (has links)
The portable electronics market is rapidly migrating towards more compact devices with multiple functionalities. Form factor, performance, cost and efficiency of these devices constitute the factors of merit of devices like cell phones, MP3 players and PDA's. With advancement in technology and more intelligent processors being used, there is a need for multiple high integrity voltage supplies for empowering the systems in portable electronic devices. Switched mode power supplies (SMPS's) are used to regulate the battery voltage. In an SMPS, maximum area is taken by the passive components such as the inductor and the capacitor. This work demonstrates a single inductor used in a buck converter with two output voltages from an input battery with voltage of value 3V. The main focus areas are low cross regulation between the outputs and supply of completely independent load current levels while maintaining desired values (1.2V,1.5V) within well controlled ripple levels. Dynamic hysteresis control is used for the single inductor dual output buck converter in this work. Results of schematic and post layout simulations performed in CADENCE prove the merits of this control method, such as nil cross regulation and excellent transient response.
486

The Method of Division and Aristotle's Criticism of Platonic Philosophy

Howton, Robert F. 2010 May 1900 (has links)
This thesis investigates Aristotle's criticism and consequent reformulation of the Platonic method for formulating definitions called the Method of Division. For both Plato and Aristotle, the object of division is a natural kind, which consists in a class whose members stand in a homologous relationship to a single form. I argue that Aristotle's criticisms of the Method of Division fall under two categories: logical objections and ontological objections. The logical objections focus on division as a method for demonstrating definitions, a method that Aristotle wants to distinguish from his syllogistic logic, the centerpiece of his theory of scientific demonstration. The ontological objections focus on the question of whether the sort of account generated by division is sufficient to constitute a definition of its object. Aristotle's revised Method of Division is supposed to avoid the problems he raises by constructing definitions that satisfy the principles motivating his ontological objections through a logical process devised to make the resulting account a "necessary" consequence of the initial assumptions of the division. I argue that Aristotle?s ontological objections to the Method of Division reflect a deeper disparity between the Platonic and the Aristotelian notion of a form and natural kind. Underpinning Aristotle's notion of a natural kind is an ontology of discrete substances. Because the unity of substance is paramount in this ontology, Aristotle argues that a definition, which is supposed to give an account of the essence of a substance, must account for the unity of its object by itself possessing a non-accidental unity. Yet, on a Platonic ontology, a definition by division invokes a plurality of independent Forms whose conjunction does not constitute a unity. On the basis of this consideration, Aristotle argues that an ontology of abstract Forms cannot account for the unity of an individual substance. To this extent, I conclude, Aristotle's methodological objections to the Platonic Method of Division are a component of his broader criticisms of Platonic metaphysics.
487

The Organization Choice of Cross Business Operation-Sampling Financial Industry Integration

Tseng, Chien-yu 09 February 2006 (has links)
none
488

Marx On Form And Ccontent: It&#039 / s All About Structure, It&#039 / s All About Artwork!

Yildirim, Baris 01 May 2011 (has links) (PDF)
This study aims at providing a reading of the first chapter of Karl Marx&lsquo / s Capital Volume One titled
489

A Study of Cheng Wen-cho's Tz'u Poetry

Chao, Kuo-Jung 23 July 2002 (has links)
none
490

Charmonium absorption and charmed hadron production in hadronic reactions

Liu, Wei 17 February 2005 (has links)
A gauged SU(4) flavor symmetric hadronic Lagrangian with empirical hadron masses is constructed to study charmonium absorption and charmed hadron production in hadronic reactions. For the coupling constants, empirical values are used if available. Otherwise, they are determined from known coupling constants using the SU(4) relations. To take into account the finite sizes of hadrons, form factors are introduced at strong interaction vertices with empirical cutoff parameters. For J/ψabsorption by nucleons, we have included both two-and three-body final states and find that with a cutoff parameter of 1 GeV at interaction vertices involving charm hadrons, the cross section is at most 5 mb and is consistent with that extracted from J/ψproduction from both photo-and proton-nucleus reactions. We have also evaluated the cross sections for charmed hadron production from pion and rho meson interactions with nucleons. With the same cutoff parameter of 1 GeV at interaction vertices, we find that these cross sections have values of a few tenths of mb and are dominated bythe s-channel nucleon pole diagram. For charmed hadron production from proton-proton reactions, their cross sections including bothtwo-andthree-body final states are about 1 batcenter-of-mass energyof 11.5 GeV, which is comparable to the measured inclusive cross section in these reactions.Including photon as a U(1) gauge particle, we have extended the model to study charmed hadron production in photon-proton reactions with both two-and three-body final states included. For form factors, an overall one is introduced in each processin order to maintain the gauge invariance of the total amplitude. Fitting the cutoff parameter in the form factor to the measured total cross section for charmed hadron production in photon-proton reactions at a center-of-mass energy of 6 GeV, the ratio of the cross sections for two-body and three-body final states is consistent with available experimental data.This result is further compared with predictions from the leading-order perturbative QCD calculation. Knowledge of the cross sections for charmonium absorption byhadrons and for charmed hadron production in hadronic reactions is essential for understanding charm production in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC), where a quark-gluon plasma is expected to be formed during the initial hot dense stage.

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