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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.
61

Om ansvar anhålles – En studie om ansvarsutkrävande inom Försäkringskassan / Accountability, if you please – A study regarding accountability within The Social Insurance Agency

Jidblad, Charlotte, Johansson, Patrik, Strauss, Nathalie January 2016 (has links)
Inom den statliga förvaltningen skall ansvarsutkrävande fungera som en garant för tjänstemännens myndighetsutövning. Det har emellertid anförts kritik mot att ansvarsutkrävandet har minskat på grund av ineffektiva processer inom den statliga förvaltningen. Det tillsynes minskade ansvarsutkrävandet avser att tydliggöras utifrån två kategorier av teoretiska förklaringar; om det föreligger en slapphetskultur eller om ansvarsutkrävandet sker på ett mer ändamålsenligt sätt. Denna uppsats syftar till att undersöka om minskningen av ansvarsutkrävande vid tjänsteförseelser inom den statliga förvaltningen är reell eller chimär. Studiet av ansvarsutkrävande har fordrat en kvalitativ metod och sker genom en fallstudie inom Försäkringskassan på lokal nivå. För att undersöka vilka uppfattningar i ansvarsfrågan som styr tillämpandet av ansvarsutkrävande inom myndigheten har tio intervjuer genomförts. Intervjupersonerna representerar olika yrkesroller som innefattas i den ansvarsutkrävande processen. De har utifrån sina erfarenheter beskrivit hur ansvarsutkrävande i praktiken sker inom myndigheten. Det empiriska materialet har analyserats utifrån tre teoretiska perspektiv; det rationella, det kulturella och det symboliska. Vilket har fört oss till slutsatsen att minskningen är chimär då myndigheten funnit mer ändamålsenliga sätt att utkräva ansvar. Det tillsynes minskade ansvarsutkrävandet kan förklaras av att myndigheten väljer att hantera tjänsteförseelser med kompetensutvecklande insatser. / Within the functions of government agencies, accountability is a necessity for civil servants to ensure that appropriate levels of authority are being exercised. However criticism has been raised, that inefficient processes within the government agencies have led to reduced accountability. This is to be explained from two categories of theoretical explanations; whether there exists a cultural looseness, or if accountability occurs in a more utilitarian way. The purpose of this study is to examine when misconduct takes place in a government agency, if reduced accountability is imminent or chimera. In order to better understand the perception of accountability in government agencies, the question has been examined regarding The Social Insurance Agency on a local level. The study requires a qualitative method and a case study limited to The Social Insurance Agency. Ten interviews were conducted. The respondents represent several different professions, with differing levels of accountability. Their perceptions have illustrated how accountability takes form in a government agency. The empirical material has been analyzed through three theoretical perspectives; the Rational, the Cultural, and the Symbolic. The conclusion is that the reduction is chimera. The Social Insurance Agency have found more utilitarian ways to hold civil servants accountable for their actions. The seemingly reduced accountability can be explained by an agency´s choice to deal with misconduct by using competence to improve actions.This study is written in Swedish.
62

THE TIMELINESS OF ASYNCHRONOUS PACKET MULTIPLEXING IN SWITCHED ETHERNET

Qiao, Li, XiaoLin, Zhang, Huagang, Xiong, Yuxia, Fei 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / Powered by single-segment switched interconnection, Ethernet can be used in time-critical data acquisition applications. Unlike synchronous time division multiple access, asynchronous packet streams result in congestions and uncertain multiplexing delays. With the delay analysis in the worst case and probabilistic guaranteeing conditions, we restrict the packet-sizes, intervals or traffic burstiness a priori to regulate delay deviations within acceptable scales. Some methods of combinatorics and stochastic theory, e.g. Cumulant Generating Function and the Large Deviation Principle, are used and verified by some simulation-based computations. The influence of time varying delay for telemetry applications is also discussed in some sense.
63

OPTIMIZED LOW BIT RATE PCM/FM TELEMETRY WITH WIDE IF BANDWIDTHS

Law, Eugene 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / This paper will present the results of some experiments with non-coherent, single symbol detection of pulse code modulation (PCM)/frequency modulation (FM) where the receiver intermediate frequency (IF) bandwidth is much wider than the bit rate. The experiments involved varying the peak deviation and measuring the bit error probability (BEP) at various signal energy per bit to noise power spectral density ratios (E(b)/N(o)). The experiments showed that the optimum peak-to-peak deviation was about 0.7 to 0.8 times the –3 dB IF bandwidth and that the E(b)/N(o) required for a given BEP increased as the ratio of IF bandwidth to bit rate increased. Further, bi-phase-level/FM performed slightly better than non-return-to-zero-level (NRZ-L)/FM with an ac coupled RF signal generator and IF bandwidths much wider than the bit rate.
64

Resource management in IP networks

Wahabi, Abdoul Rassaki 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: lP networks offer scalability and flexibility for rapid deployment of value added lP services. However, with the increased demand and explosive growth of the Internet, carriers require a network infrastructure that is dependable, predictable, and offers consistent network performance. This thesis examines the functionality, performance and implementation aspects of the MPLS mechanisms to minimize the expected packet delay in MPLS networks. Optimal path selection and the assignment of bandwidth to those paths for minimizing the average packet delay are investigated. We present an efficient flow deviation algorithm (EFDA) which assigns a small amount of flow from a set of routes connecting each OD pair to the shortest path connecting the OD pair in the network. The flow is assigned in such a way that the network average packet delay is minimized. Bellman's algorithm is used to find the shortest routes between all OD pairs. The thesis studies the problem of determining the routes between an OD pair and assigning capacities to those routes. The EFDA algorithm iteratively determines the global minimum of the objective function. We also use the optimal flows to compute the optimal link capacities in both single and multirate networks. The algorithm has been applied to several examples and to different models of networks. The results are used to evaluate the performance of the EFDA algorithm and compare the optimal solutions obtained with different starting topologies and different techniques. They all fall within a close cost-performance range. They are all within the same range from the optimal solution as well. / AFRIKAANSE OPSOMMING: lP-netwerke voorsien die skaleerbaarheid en buigsaamheid vir die vinnige ontplooing van toegevoegde-waarde lP-dienste. Die vergrote aanvraag en eksplosiewe uitbreiding van die Internet benodig betroubare, voorspelbare en bestendige netwerkprestasie. Hierdie tesis ondersoek die funksionaliteit, prestasie en implementering van die MPLS(multiprotokoletiketskakel)- meganismes om die verwagte pakketvertraging te minimeer. Ons bespreek 'n doeltreffende algoritme vir vloei-afwyking (EFDA) wat 'n klein hoeveelheid vloei toewys uit die versameling van roetes wat elke OT(oorsprong-teiken)- paar verbind aan die kortste pad wat die OT-paar koppel. Die vloei word toegewys sodanig dat die netwerk se gemiddelde pakketvertraging geminimeer word. Bellman se algoritme word gebruik om die kortste roetes tussen alle OT-pare te bepaal. Die tesis bespreek die probleem van die bepaling van roetes tussen 'n OT-paar en die toewysing van kapasiteite aan sulke roetes. Die EFDA-algoritme bepaal die globale minimum iteratief. Ons gebruik ook optimale vloeie vir die berekening van die optimale skakelkapasiteite in beide enkel- en multikoers netwerke. Die algoritme is toegepas op verskeie voorbeelde en op verskillende netwerkmodelle. Die skakelkapasiteite word aangewend om die prestasie van die EFDAalgoritme te evalueer en dit te vergelyk met die optimale oplossings verkry met verskillende aanvangstopologieë en tegnieke. Die resultate val binne klein koste-prestasie perke wat ook na aan die optimale oplossing lê.
65

Beiträge zur Richtighaltung von Kreisformmessgeräten

Miethling, Klaus-Dietmar 04 May 2016 (has links) (PDF)
In der Arbeit werden normativ-technische und verfahrenstechnische Voraussetzungen zur Richtighaltung von Kreisformmessgeräten dargelegt. Dazu wird ein umfassendes Begriffssystem für die allgemeine Beschreibung von Bewegungsabweichungen von bewegten Bauteilen an Werkzeugmaschinen oder Formmessgeräten, z.B. Kreisformmessgeräten, als Grundlage für ihre Tolerierung und Messung vorgeschlagen. Bekannte Messverfahren zur Bestimmung von Rotationsabweichungen der Spindel von Kreisformmessgeräten werden theoretisch und praktisch untersucht. Es wird ein neues Messverfahren, das kontinuierliche Relativlagenmessverfahren, entwickelt und ebenfalls untersucht. Die untersuchten Messverfahren zur Bestimmung von Rotationsabweichungen ermöglichen verschiedene Messunsicherheiten bis zu weniger als 0,02 µm. Vorschläge für die Gestaltung des Prüfschemas zur Richtighaltung von Kreisformmessgeräten werden unterbreitet. auch unter: Zentralbibliothek/Magazin/MPF1443
66

Optimum Subcarrier Deviation for PCM/FM+FM/FM Systems using IRIG Constant Bandwidth Channels

Osborne, William P., Whiteman, Donald E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A typical PCM/FM system is designed for a peak to peak carrier deviation of 0.7 times the bit rate of the PCM data. This value of PCM data deviation has been shown to be optimum for both PCM/FM [1] and PCM/FM+FM/FM [2] systems. However, the optimum deviation of the carrier by the FM subcarrier for a PCM/FM+FM/FM system is dependent upon the specific subcarrier type and required subcarrier signal to noise ratio at the receiver output. This paper introduces a simple method to calculate the optimum deviation of the carrier by FM subcarriers for a PCM/FM+FM/FM system. The method developed is used to calculate the optimum value of subcarrier deviation for two sample PCM/FM+FM/FM systems when IRIG constant bandwidth channels are used as FM subcarriers. The calculated optimum values of FM subcarrier deviation of the carrier, subcarrier mod index, are utilized in a companion paper to study the performance of PCM/FM+FM/FM systems [3]. The work presented herein can be extended to calculate the optimum deviation of the carrier by FM subcarriers for any PCM/FM+FM/FM system.
67

THE GREAT FREQUENCY DEVIATION AUTOMATIC MEASURING OF TELEMETRY TRANSMITTER

Bixian, Luo, Jian, Luo, Wei, Zeng 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / At present, there is no means of instrument direct measurement to frequency deviation when it is up 500kHz. But the frequency deviation of high bit rate telemetry transmitter is 700kHz or more. In this paper, an indirect measurement method using spectrum analyzer and counter is put forward. It effectively solves the measurement problem of frequency deviation and frequency response of high bit rate telemetry transmitters. Measuring theory, summary of experiences and difficulties in measuring work, have been deeply studied with the viewpoint of how to avoid the limitation of different methods of measurement. Focused on the establishment of an automatic measuring system, expert system, skilled data and software of the system are studied in detail. The data for comparison is also supplied. Finally, the analysis to the measuring error and general uncertainty is given.
68

A stochastic analysis of Turbulence Intensity influence over various sizes of HAWT : Study of hypothetical relationship between Rotor Diameter and influence level of Turbulence Intensity / En stokastisk analys av turbulensintensitet inflytande över olika storlekar av HAWT : Studie av hypotetisk relation mellan rotordiameter och inflytande nivå turbulensintensitet

Nicholas, Allen Christo January 2016 (has links)
This disquisition aims for the study of turbulence intensity influence over the power performance of different sizes of turbines with the intent to validate a hypothesis. The hypothesis formulated for the analysis is the relationship between the rotor diameter (turbine size) and turbulence intensity. The hypothetical relationship is that the smaller turbines tend to experience more influence on the power performance from the turbulence in comparison with larger ones. For this examination, three different wind turbines of models Vestas V90, V100, V126 were chosen from three Swedish wind farms. The power performance of turbines at various levels of turbulence intensity were analyzed and the power deviation from the mean value due to influence of turbulence were assessed. The power deviation values of different turbines were compared at same level of wind speeds and also the power coefficients at same level of tip speed ratios were compared to validate the hypothesis. It was observed that the hypothesis seemed to appear true as higher influence on power curves were observed on V90 compared to others. Nevertheless, there were some obscene results which might be due to several factors such as influence of variation in hub height, site and inadequacy of data. / Detta examensarbete syftar till att studera hur ett vindkraftverks storlek påverkar inflytande från turbulens på effektuttaget. Hypotesen är att vindkraftverk med mindre rotordiameter påverkas mer av turbulens än de större. Tre vindkraftverksmodeller (Vestas V90, V100 och V126) från svenska vindkraftsparker valdes ut. De olika modellernas effektuttag för olika grader av turbulens analyserades och avvikelsen från effektmedelvärdet jämfördes. Effektavvikelserna samt verkningsgradsavvikelsen  för de olika vindkraftverksmodellerna jämfördes vid samma vindhastighet respektive löptal för att kunna testa hypotesen. Hypotesen styrks då den mista modellen (Vestas V90) påverkas mest av turbulens. Resultatet har dock troligtvis påverkats av andra faktorer såsom tornhöjd, terräng och en begränsad mängd data.
69

Large Deviations on Longest Runs

Zhu, Yurong January 2016 (has links)
The study on the longest stretch of consecutive successes in \random" trials dates back to 1916 when the German philosopher Karl Marbe wrote a paper concerning the longest stretch of consecutive births of children of the same sex as appearing in the birth register of a Bavarian town. The result was actually used by parents to \predict" the sex of their children. The longest stretch of same-sex births during that time in 200 thousand birth registrations was actually 17 t log2(200 103): During the past century, the research of longest stretch of consecutive successes (longest runs) has found applications in various areas, especially in the theory of reliability. The aim of this thesis is to study large deviations on longest runs in the setting of Markov chains. More precisely, we establish a general large deviation principle for the longest success run in a two-state (success or failure) Markov chain. Our tool is based on a recent result regarding a general large deviation for the longest success run in Bernoulli trails. It turns out that the main ingredient in the proof is to implement several global and local estimates of the cumulative distribution function of the longest success run.
70

Enough is Enough : Sufficient number of securities in an optimal portfolio

Barkino, Iliam, Rivera Öman, Marcus January 2016 (has links)
This empirical study has shown that optimal portfolios need approximately 10 securities to diversify away the unsystematic risk. This challenges previous studies of randomly chosen portfolios which states that at least 30 securities are needed. The result of this study sheds light upon the difference in risk diversification between random portfolios and optimal portfolios and is a valuable contribution for investors. The study suggests that a major part of the unsystematic risk in a portfolio can be diversified away with fewer securities by using portfolio optimization. Individual investors especially, who usually have portfolios consisting of few securities, benefit from these results. There are today multiple user-friendly software applications that can perform the computations of portfolio optimization without the user having to know the mathematics behind the program. Microsoft Excel’s solver function is an example of a well-used software for portfolio optimization. In this study however, MATLAB was used to perform all the optimizations. The study was executed on data of 140 stocks on NASDAQ Stockholm during 2000-2014. Multiple optimizations were done with varying input in order to yield a result that only depended on the investigated variable, that is, how many different stocks that are needed in order to diversify away the unsystematic risk in a portfolio. / <p>Osäker på examinatorns namn, tog namnet på den person som skickade mejl om betyg.</p>

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