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On low-complexity frequency selective digital filters and filter banksRosenbaum, Linnea January 2007 (has links)
En filterbank består av flera filter som arbetar tillsammans för att dela upp en signal i olika frekvensband. De kan också användas för att slå ihop signaler separerade i frekvensplanet till en enda. Sedan tidigt 70-tal har man lärt sig att designa förlustfria filterbankar som alltså inte introducerar några som helst fel i systemet. Sådana filterbankar kallas PR-filterbankar, där PR står för 'perfekt rekonstruktion'. Exempel på applikationer där filterbankar används är bildkodning, audiokodning, kommunikationssystem och omvandling av analoga signaler till digitala (A/D-omvandling). Under de senaste åren har det framkommit att genom att lätta på kraven gällande perfekt rekonstruktion, går det att markant minska den erforderliga aritmetiska komplexiteten. Eftersom de flesta system i sig inte är förlustfria, kan man utan att egentligen påverka den totala prestandan tillåta små fel i filterbanken, så l¨ange dessa fel är försumbara i jämförelse med andra felkällor som t.ex. kvantisering och avrundning. Avhandlingen behandlar digitala filter och likformiga icke-PR-filterbankar. Merparten av filterbankarna är realiserade med någon slags moduleringsteknik (cosinus-, sinus- eller komplexmodulering). Den röda tråden genom avhandlingen är kombinationen av tämligen smala övergångsband och samtidigt låg aritmetisk komplexitet. Ett sätt att uppnå denna kombination är att använda sig av en teknik som heter frekvenssvarsmaskning och förkortas FRM. Denna metod har på ett framgångsrikt sätt använts i avhandlingen. En potentiell nackdel med FRMmetoden är att den medför en längre fördröjning genom systemet. Därför föreslås också ett sätt att syntetisera FRM-filter med låg fördröjning. Här optimeras filtren både med avseende på komplexitet och fördröjning samtidigt. En annan metod som utnyttjats för att kombinera relativt smala övergångsband med låg aritmetisk komplexitet är att använda IIR filter istället för FIR filter. Ett flertal exempel på filter och filterbankar, optimerade och syntetiserade i Matlab, illustrerar fördelarna med de föreslagna filter- och filterbanks-klasserna. / Filter banks are systems of several filters with a common input or a common output. They are used whenever a signal needs to be split into different frequency bands. Since the early seventies, the theory of digital filter banks has developed to a mature state. Today there exist numerous ways to design filter banks for different applications, such as image and audio coding, transmultiplexing in communication systems, echo cancellation, and analog-to-digital (A/D) conversion systems. However, earlier work has to a large extent been on the transfer function level, whereas in this thesis work, efficient realizations, important in e.g. low-power applications, are in focus. Further, most of the previous work have been focused on the perfect reconstruction (PR) case, which is, for many applications an unnecessarily severe restriction. It has been show that by relaxing the requirements on perfect reconstruction, and allowing the filter banks to have some errors, the arithmetic complexity can be reduced significantly. This thesis treats digital filters and uniform non-PR filter banks. A major part of the filter banks are realized using different modulation schemes (complex, cosine, or sine modulation). The governing idea through the thesis is the combination of frequency selectivity and low arithmetic complexity. One example on how to achieve frequency selective digital filters and filter banks with low arithmetic complexity is to use the frequency-response masking (FRM) approach. This approach together with the idea of using IIR filters instead of FIR filters is successfully used in the thesis. The price to pay for the reduced arithmetic complexity using FRM filters is unfortunately a longer overall delay. Therefore, some work has ben done in the field of low-delay FRM FIR filters as well. These filters are optimized on both low delay and low arithmetic complexity simultaneously. A number of design examples are included in order to demonstrate the benefits of the new classes of filters and filter banks.
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Projekt dětského členství v AC Sparta Praha / AC Sparta Prague Kids membership projectPašková, Barbora January 2017 (has links)
Title: AC Sparta Prague Children's Membership Project Objectives: The main aim of the Diploma Thesis is a proposal to improve the project of the children's membership in the Kids Club and the Teens Club in AC Sparta Prague based on the current state of the project and the results of the marketing research. Methods: The main methods of collecting data and information used in this thesis were a marketing research focused on the satisfaction of the registered members and an in-depth interview with the manager of the project. The method includes an analysis of documents. Results: Based on the description and feedback from the current members, the Kids Club and the Teens Club may be considered a successful project falling within the overall philosophy of AC Sparta Prague. The overall concept of the children's membership project may be considered properly set, too. The selected method of registration and the registration form are evaluated positively however the pace of the whole registration process is slow. Most of the total number of the registered members are from the Capital City and the surrounding area and most of them are males. The members are satisfied with the membership offer and the existing events but they would welcome more events with the players. A weak point of the project is its...
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Parametric Structural Optimization of a Wheel Using the Flex Representation MethodVernon, Gregory John 13 December 2022 (has links)
The use of the finite element method within an optimization workflow is fraught with challenges that limit the automation of such workflows. These challenges are inherent to the traditional finite element formulations which are heavily dependent on a manual meshing process that introduces variability that is challenging to account for within an automated workflow. The recently developed flex representation method (FRM) provides a salient solution to the manual meshing process without sacrificing solution accuracy. In response to the development of FRM a global automotive company requested a study to explore the applicability of FRM to one of their sizing-optimization problems: the constrained optimization of a wheel undergoing a rigidity test. In this study we develop an optimization framework based on the DAKOTA optimization framework, the open-source FreeCAD computer-aided design software, and an implementation of FRM within the Coreform IGA solver. Within this framework we demonstrate in the affirmative that FRM enables a highly robust sizing-optimization workflow while requiring minimal effort to prepare the FRM model.
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Evaluation of PM10 and Total Suspended Particulate Sampler Performance Through Wind Tunnel TestingThelen, Mary Katherine 2010 August 1900 (has links)
Particulate matter (PM) concentrations in ambient air can be monitored by
gravimetric sampling near a source using Federal Reference Method (FRM) samplers.
PM is regulated by size, with PM10, which is comprised of particles with aerodynamic
equivalent diameters less than or equal to 10 μm, being the main focus of this research.
FRM PM10 samplers exhibit sampling errors when sampling dusts with mass median
diameters (MMDs) that are larger than the 10 μm sampler cutpoint. For industries to be
regulated equitably, these sampler errors must be quantified and understood.
This research evaluates the performance of FRM PM10 and low volume total
suspended particulate (TSP) samplers under the controlled conditions of a wind tunnel.
The performance evaluation was conducted by observing the sampler cutpoints, slopes,
and measured concentrations. These measured values were compared to values obtained
using a collocated isokinetic reference sampler.
The results of this research indicate that PM10 samplers do not operate as
intended under all conditions. The cutpoint of the PM10 inlets was significantly higher
than the maximum FRM limit of 10.5 μm when sampling dust with MMDs larger than the cutpoint of the sampler. The slope values for the PM10 inlets were significantly
higher than the maximum FRM limit of 1.6.
MMDs and geometric standard deviations of PM collected by TSP samplers were
significantly different than those of PM collected using the collocated isokinetic
sampler. The concentrations measured by the TSP samplers were significantly higher
than the collocated isokinetic sampler.
The results of this research provide a better understanding of the performance of
TSP and PM10 samplers operating under different conditions and shows that these
samplers are not operating as intended. Because of this, industries may be suffering the
consequences of inequitable regulation.
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Návrh projektu a aplikace metodiky projektového managementu v podniku / Proposal for Project and Application of Project Management Methodology in the CompanyMarkulchak, Alina January 2021 (has links)
Ths bhlr thss s fusd n prjt mngmnt n n th sltd mpny. Th frst prt f th thss dsrbs th thrtl knwldg f prjt mngmnt. Th snd nlytl prt s dvtd t th bs nfrmtn but th mpny nd th nlyss f th urrnt stutn n th mpny. Th lst prt f wrk nluds suggstns fr hngs n th mpny nd dsrbs th bnfts f ths hngs.
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Assessment of river discharge changes in the Indochina Peninsula region under a changing climate / 地球温暖化時のインドシナ半島における河川流量の変動評価Duong Duc Toan 23 January 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18690号 / 工博第3968号 / 新制||工||1611(附属図書館) / 31623 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 立川 康人, 教授 中北 英一, 准教授 KIM Sunmin / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Cost-push shocks and monetary policy transmission under the existence of fixed rate mortgage contracts and high indebtednessBackberg, Emma January 2023 (has links)
This thesis examines the transmission of monetary policy and the effects of persistent cost-push shocks in the presence of high household indebtedness (DTI) and frictions in fixed-rate mortgage (FRM) interest rates. A dynamic stochastic general equilibrium (DSGE) model incorporating housing, household debt, and long-term FRMs is estimated to accomplish this. The key findings can be summarized as follows: (i) A higher DTI leads to a stronger transmission of monetary policy, although this effect is dampened by the degree of interest rate fixation periods. (ii) Cost-push shocks propagates more strongly to inflation when the interest rate fixation periods is longer, resulting in delayed and slightly muted effects on output and consumption compared to adjustable-rate mortgages (ARM). (iii) While stronger responses to inflation help mitigate the cost-push shock, this comes at the expense of a larger output gap but with a slightly faster stabilization of the economy with a somewhat steeper recovery.
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Shoulder Abduction and Flexion Movements Measured with the Force Range Monitor - A Validation Study / Axel abduktions- och flexionsrörelser uppmätt med en Force Range Monitor - En valideringsstudieRahman, Promi, Lazarz, Karolina January 2021 (has links)
The life expectancy of the elderly population is expected to increase with 22 % by 2050. As one grows older, the body starts to deteriorate, which can lead to a higher risk for diseases and accidents. During recent years shoulder surgeries have increased dramatically, and to assess the shoulder function the most common technique is the use of camera-based motion capture systems. However, this is very time consuming and does not completely represent the real shoulder performance. Therefore, this study was aimed to validate a new technique, the force range monitor (FRM). Thirteen volunteers participated in this study, which was divided into two sessions. Session one included abduction and flexion strength measurements using the FRM, as well as six mobility measurements with the inertial measurement unit (IMU) of the FRM. The second session was conducted in the same manner, with the addition of the Vicon system (motion capture system). In this study a control session for FRM and the Vicon system was also performed for abduction and flexion movements with two participants, where the placement of the IMU was modified. As indicated by the results, FRM and the Vicon system do not measure the same parameters. Even if the FRM does not measure the same shoulder joint angles as the Vicon System, the FRM can still be of clinical importance when evaluating position deviation during strength and mobility measurements. Moreover, the FRM had a high repeatability for a number of participants, and most of the mobility measurements presented a distinct patterns for various activities. Hence, it can be concluded that the FRM is a potential technique to evaluate shoulder strength and mobility.
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Analyse biomécanique et électromyographique des éléments d'anticipation de l'initiation de déplacement en fauteuil roulant manuel / Biomechanics and electromyographic analysis of anticipation elements of the manual wheelchair initiation displacementChikh, Soufien 19 June 2015 (has links)
Les Personnes à Mobilité Réduite (PMR) souffrent souvent de limitation au cours de la locomotion. Plusieurs outils sont à leurs dispositions pour les aider et les assister dans leur déplacement, plus particulièrement le Fauteuil Roulant Manuel (FRM) ou électrique. Ces travaux de thèse se focalisent sur les interactions entre le sujet et le FRM afin de déterminer des éléments prédictifs du déplacement à venir dans l’optique d’une aide à la locomotion. Comprendre l'Interaction Homme-FRM (IHF) est un enjeu actuel afin d'améliorer le déplacement et d’optimiser la performance ainsi que le confort, en minimisant la fatigue et les risques des blessures. Pour contribuer à mieux comprendre voire améliorer cette IHF, un ensemble d'études centrées sur une analyse biomécanique et électromyographique des éléments d'anticipation de l'Initiation du Déplacement en FRM (ID-FRM) a été réalisé au cours de ces travaux de thèse. Cet ensemble d’études porte sur i) les Activités Musculaires Anticipatoires (AMA) en position assise pour interroger la prédictibilité des mouvements au regard de ses paramètres préalables ; ii) l’évolution des patterns musculaires et des pressions sur l'assise lors de l'ID-FRM, pour interroger l’adaptabilité ou la spécificité des paramètres initiaux lors de différents déplacements en FRM chez des sujets valides. ; iii) l’évolutions des patterns musculaires et des pressions sur l'assise lors de l'ID-FRM chez des sujets blessés médullaires et ; iv) l’analyse multi-variée des paramètres de l'ID-FRM. Le SNC présente des capacités d'adaptabilité importantes au mouvement à venir en ajustant les commandes motrices aux conditions physiologiques globales du sujet. Cette adaptabilité a conduit à des pourcentages importants de prédiction et elle peut être enregistrée au travers d'éléments macroscopiques permettant d'envisager des systèmes d'aide au déplacement, notamment pour les PMR. / People with Disabled Mobility (PDM) often suffer from limitation during locomotion. Several tools are at their disposal to help and assist them in their displacement, specifically the electric or the Manual Wheelchair (MW). This thesis works focuses on the Human-MW-Interaction (H-MW-I) subject to determine elements predictors of forthcoming displacement with a view of aid to locomotion. Understanding (H-MW-I) is a current challenge to improve the displacement and optimize the performance as well as comfort, by minimizing fatigue and injury risk. In order to enhance understanding and even improving the (H-MW-I), a set of studies focusing on Biomechanics and electromyographic analysis of anticipation elements of the Manual Wheelchair Initiation Displacement (MW-ID) was performed during the thesis works. This set of studies focuses on i) Anticipatory Muscular Activities (AMA) in the sitting position to question the predictability of the movements in relation to its prior parameters; ii) evolution of muscular patterns and pressures on the seat when MW-ID to question the adaptability or specificity of the initial parameters during various displacements using MW in healthy subjects ; iii) evolution of muscular patterns and pressures on the seat when MW-ID in spinal cord injury subjects and; iv) multivariate analysis of the MW-ID parameters. The CNS presents an important capacity of adaptability to the forthcoming movement by adjusting motor commands to the global physiological condition of the subject. This adaptability has led to significant percentages prediction and it can be saved through macroscopic elements to envisage help systems to displacement for PDM.
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Analyse des Sportunterrichts in der Arabischen Republik Ägypten / Analysis of Physical Education lesson in the Arab Republic EgyptOsman, Ashraf 13 October 2004 (has links)
No description available.
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