The robustness of the stability property of multivariable feedback control systems with respect to model uncertainty is studied and discussed. By introducing a topological notion of arcwise connectivity, existing and new robust stability tests are combined and unified under a common framework. The new switching-type robust stability test is easy to apply, and does not require the nominal and perturbed plants to share the same number of closed right half-plane poles, or zeros, or both. It also highlights the importance of both the sensitivity matrix and the complementary sensitivity matrix in determining the robust stability of a feedback system. More specifically, it is shown that at those frequencies where there is a possibility of an uncertain pole crossing the jw-axis, robust stability is "maximized" by minimizing the maximum singular value of the sensitivity matrix. At frequencies where there is a likelihood of uncertain zeros crossing the imaginary axis, it is then desirable to minimize the maximum singular value of the complementary sensitivity matrix. A robustness optimization problem is posed as a non-square H^∞-optimization problem. All solutions to the optimization problem are derived, and parameterized by the solutions to an "equivalent" two-parameter interpolation problem. Motivated by improvements in disturbance rejection and robust stability, additional optimization objectives are introduced to arrive at the 'best' solution.

Syfte och frågeställningar: Syftet är att undersöka och jämföra tre kommuners kommunikation på Facebook, men också fenomenet Facebook och dess komponenter i form av exempelvis gilla-markeringar. Studien bygger på två huvudfrågor. 1. Vilken typ av kommunikation bedrivs via kommunernas Facebooksidor? 2. Hur skiljer sig kommunikationen åt mellan de tre kommunerna? Metod och material: Intervjuer och netnografiska observationer. Huvudresultat: Facebook är en viktig kommunikationskanal för kommunerna. Intervjuerna visar att mycket av det som kommunernas kommunikatörer säger sig kommunicera stämmer in på det som de netnografiska observationerna visat och att de huvudsakligen lever upp till sina uttalade syften. Något som kan konstateras är att oberoende av hur många följare eller hur mycket feedback en kommuns Facebooksida får så gör det ingen större skillnad i hur de bedriver kommunikationen. Alla tre kommunerna har som mål att föra dialog med sina följare via Facebooksidan. Av observationerna att utläsa är det dock endast Karlstad kommun som aktivt bjuder in följarna till att bidra med innehåll. Alla tre undersökta kommuner har varsin policy som är utfärdad för hur de ska arbeta med sociala medier, vilket alla kommuniktörer förhåller sig till i arbetet med Facebooksidan. Med resultat från både intervjuer och observationer kan tre stycken ledord urskiljas som beskriver den kommunikation kommunerna bedriver; informera, interagera och engagera.

国立情報学研究所で電子化したコンテンツを使用している。

No description available.

Background: During the last 20 years there have been different approaches to teaching nurse students cardiopulmonary resuscitation (CPR). Receiving CPR with compressions of adequate depth and frequency, and ventilations of adequate volume improves the chance of survival. The aim of this study was to evaluate effects of different types of feedback on CPR skills among nursing students. Methods: A pilot study with an explorative approach including 30 nurse students. Students was randomized in three groups; 1) instructor-led training followed by self-training without feedback, 2) self-training with visual graphic feedback, and 3) self-training with voice advisory manikin (VAM). Outcomes were correct compression deep, frequency, hand position and release, and correct ventilation volume and flow. If performance was correct to 70%, students were considered to have reached approved level. The students also answered questions about theoretical knowledge about CPR. Results: In technical skills, group 2 had significant higher level of correct ventilation volume compared with the other group. Both group 1 and 3 did not reach the level of 70% correct performance. Group 1 and 2 had significant higher level of correct deep of compressions compared with group 3 which did not reach the 70% level. There was no difference in performance between groups in other parameters. Conclusion: This pilot study suggests that visual graphic feedback is promising and seemed to be more effective than self-training with voice advisory manikin and instructor-led training with followed self-training without feedback.

Thesis (PhD)--University of South Australia, 2000

Thesis (PhD)--University of South Australia, 2000

Thesis (M.S.)--Villanova University, 2007. / Psychology Dept. Includes bibliographical references.

Zugl.: Linz, Univ., Diplomarbeit, 2006 / Hergestellt on demand

Thesis (M.S.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 17, 2009) Includes bibliographical references.