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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.
51

Framtagning av ny cykelbelysning med ljussignalering / Development of new bicycle lights with signal lights

Ghorbani, Nathalie January 2018 (has links)
Syftet med projektet var att ta fram en ny cykelbelysning för att höja cyklisters säkerhet och förenkla trafikregler samt utförandet av signalering. Genom en nulägesanalys av befintliga produkter, elektronikkomponenter och slutanvändarnas uttalanden kunde kundbehov tas fram. Därefter rangordnades kundbehoven och en funktionslista tillsammans med en produktspecifikation kunde verkställas. Med dem som grund utfördes en idégenerering med flera olika lösningskoncept där ett val gjordes baserat på en Kesselringmatris. Det vinnande konceptet var ett par pedaler med integrerad belysning. Genom en accelerometer fungerar pedalen som en bromslykta och med hjälp av en extern kontroll kan körriktningsvisare sättas igång som projiceras på marken. Elektriciteten som behövs till pedalernas belysning genereras när cyklisten roterar pedalaxeln via en generator. Som slutsats uppfylldes projektets mål men mer arbete behöver göras kring projektets avgränsningar för en färdig produkt. / The purpose of the project was to develop a new bicycle light in order to improve cyclists’ safety and to make it easier for them to follow traffic regulations. Using a status analysis of existing products, electronics and the end users statements the customer needs could be documented. Then the needs were ranked and a function list together with a product specification was produced. With them as a base the brainstorming could begin where multiple concept solutions were made and one of them chosen as a winner through a Kesselring matrix. The winning concept was a pair of pedals with integrated lighting. With the help of an accelerometer the pedal worked as a brake light and with an external control system turn signals could be turned on and were projected on the ground. The electricity needed for the pedals light system is generated when the user rotates the pedal axis with the help of a generator. As a conclusion all the project goals were fulfilled but more work needs to be done regarding the projects limitations for a complete production ready product.
52

Pedalkraft, Muskelaktivität und physiologische Kenngrößen auf Ergometer, Laufband und Bahn bei Elitebahnradsportlern

Strunz, Janine 12 December 2011 (has links)
Auf der Radrennbahn können Leistungsdiagnostik und Techniktraining nur sehr eingeschränkt durchgeführt werden. Alternativen bieten sich mit Ergometer (Ergo) und Laufband (LB). Das erste Ziel dieser Arbeit war zu klären, inwieweit sich EMG, Pedalkraft und physiologische Kenngrößen beim Radfahren auf dem Ergo oder auf dem LB vom Radfahren auf der Bahn unterscheiden. Um die Wettkampfleistung beeinflussen zu können, müssen die Besonderheiten des Muskelkoordinationsmusters sowie des Tangentialkraft-Winkel-Kurvenverlaufes im wettkampfspezifischen Intensitätsbereich erkannt werden. Das zweite Ziel der Arbeit war daher die Analyse von Muskelaktivität und Tangentialkraft bei wettkampfnaher Belastung auf der Radrennbahn, um hieraus Erkenntnisse für die Trainingspraxis zu gewinnen. Im ersten Ergebnisteil zeigten sich signifikante Unterschiede für die physiologi-schen Kennwerte, die Tangentialkraft und die Muskelaktivität im Vergleich Bahn vs. Ergo (U1) sowie Bahn vs. LB (U2). Die mittlere Tangentialkraft und die physiologischen Kennwerte waren in der U1 und U2 auf der Bahn signifikant geringer als auf dem Ergo bzw. LB. Die Aktivität einiger Muskeln wies hingegen auf der Bahn signifikant höhere Werte auf als beim Ergo- und LB-Test. Im Vergleich Bahn vs. Ergo konnten für sechs und im Vergleich Bahn vs. LB für zwei der zehn abgeleiteten Muskeln signifikante Unterschiede nachgewiesen werden. Aus den Ergebnissen des ersten Untersuchungsteils kann gefolgert werden, dass für die Leistungsdiagnostik und das Techniktraining das LB dem Ergo vorgezogen werden sollte. Im zweiten Ergebnisteil wurde nachgewiesen, dass bestimmte Muskeln an der Anpassung der gesamten muskulären Beanspruchung an die wettkampfnahe Belastung besonders stark beteiligt sind. Im Kraft- und Radtraining sollte diesen Muskeln besondere Beachtung zukommen. Auch die Tangential-Kraft-Winkelkurve wies bei wettkampfnaher Belastung Besonderheiten auf, welche mit einem Feedbacktraining angesteuert werden könnten. / Performance diagnostics and technical training can only be carried out in a re-stricted manner on the cycling track. The alternatives are the ergometer (ergo) and treadmill (TM). The first objective of this paper was to clarify to what extent EMG, pedal force and physiological parameters during cycling on the ergo or TM differ from cycling on the track. The peculiarities of the muscle coordination pattern as well as the tangential force-angle-course of curve in the intensity range specific to competition must be recognized to be able to influence performance. The second objective of the paper was therefore the analysis of muscle activity and tangential force during stress on the cycle track close to the race to obtain findings for practical training as a result. In the first part of the results there were significant differences for the physio-logical parameters, the tangential force and the muscle activity when comparing track and ergo (U1) as well as track and TM (U2). The average tangential force and the physiological parameters in U1 and U2 on the track were significantly lower than on the ergo or TM. The activity of some muscles on the track, however, showed significantly higher values than on the ergo and TM test. When comparing track vs. ergo six of the ten derived muscles showed significant differences, when comparing track vs. TM it was two of the ten muscles. We can conclude from the results of the first part of the investigation that the TM is preferable to the ergo for performance diagnostics and technical training. The second part of the results showed that certain muscles play a significant role in the adaptation of the entire muscular stress to stress during the race. Special attention should be paid to these muscles during strength and cycle training. The tangential force-angle curve also showed peculiarities during stress close to the race, which could be controlled with feedback training.
53

The effects of energy quantity to the reproductive strategies of the sea anemone Aiptasia pulchella Carlgren 1943

Chen, Chien-Hsun 26 June 2000 (has links)
The effects of energy quantity to the reproductive strategies of the sea anemone Aiptasia pulchella Carlgren 1943 Chien-Hsun Chen (Advisors: Drs. Keryea Soong, Chao-Lun Chen) Institute of Marine Biology, National Sun Yat-Sen University, Kaohsiung, 804, Taiwan, R.O.C. Thesis abstract The influences of energy quantity on the sexual and asexual reproduction and possible trade-offs between them in the sea anemone, Aiptasia pulchella were investigated. Different feeding frequencies, light intensities and presence of zooxanthellae were the treatments of energy quantity. Lacerate numbers, lacerate sizes and total weight of lacerates were used to quantify investment in asexual reproduction; oocyte sizes and gonad weights were used as the measures of sexual reproduction. The correlation between total weight of lacerates and that of gonads provided an opportunity for evidence of trade-offs between sexual and asexual reproduction. Under higher feeding frequencies, A. pulchella produced more and larger lacerates as well as larger oocytes and heavier gonads than under lower feeding frequencies. Under lower light intensities, A. pulchella produced more and heavier lacerates with than without zooxanthellae. Lacerate sizes were influenced by light intensities, presence of zooxanthellae and the interaction of the two factors. At intermediate light intensity (2000 lux), Aiptasia pulchella produced heavier gonads than at 0 lux or 10000 lux. A. pulchella produced heavier gonads with than without zooxanthellae. The oocyte sizes of A. pulchella were also influenced by light intensities, zooxanthellae and the interaction of the two. In both sexual or asexual modes of reproduction, A. pulchella performed better under higher than lower feeding frequencies. There were higher level of asexual reproduction for A. pulchella under lower light intensities with zooxanthellae. A. pulchella achieved the highest levels of fecundity, as an indication of sexual reproduction, under a light intensity of 2000 lux in individuals containing zooxanthellae. There is a positive correlation between sexual and asexual investment under different energy regimes. This is not compatible with the prediction of the trade-off hypothesis.
54

Pedalkraft system : Stödsystem för elproduktion i småskalighet

Amaya, Jorge January 2013 (has links)
Detta examensarbete vänder sig till personer som är intresserade att använda nya miljövänligametoderna för elproduktion eller personer som redan använder små vindkraftverk ochsolpaneler med behovet av en extra energikälla i små stugor eller avlägsna platser där tillgångentill elnät är omöjligt. Syften i detta arbete är först och främst att bygga ett system förelproduktion med hjälp av en cykel. Sedan bestämma mängden av elektrisk energi en personkan alstra med systemet. Slutligen svara om detta system skulle kunna använda som ettstödsystem för elproduktion i småskalighet. Den första målsättningen är att utforma ett system med användning av kraftelektronik där denkraften som genereras matar lasterna. Den mekaniska delen kommer att konstrueras som en delav energikällan, därefter kommer det att utformas en kontroll för att styra effekten viaelektroniska komponenter, de elektriska belastningarna matas av systemet, kommer attsimuleras. För att veta den alstrade effekten till styrkrets kommer det att installeras en mätareoch en seriekommunikationsenhet för kommunikation med en dator. Det utfördes en forskning av andra system och produkter i svenska marknaden, för att svara omdetta system kan vara en reserv system för elproduktion i småskalighet. Uppförandet av ett pedalkraftssystem uppnås med användning av en tolv volt likströmsmotormed permanent magnet som energikälla. System har förmåga att visa i en LCD-skärm och sändagenom serieportarna, värde av den alstrade effekten. System kan vägleda denna effekt tillbelastningarna med hjälp av en mikrokontroll. Effekt som genereras i systemet visades att detär signifikant för att beaktas som en ytterligare energikälla, fristående eller integrerad till andra system. / This thesis is aimed at people who are interested in using the new environmentally friendlymethods of electricity generation or people who already use small wind turbines and solarpanels with the need for an additional energy source in small cabins or remote locations whereaccess to electricity networks is impossible. Aims of this work is first to build a system forgenerating electricity using a bicycle. Second is determining the amount of electrical energy aperson can generate with the system. Finally answer if this system could be used as a supportsystem for electricity generation in small scale. The first objective is to design a system using power control where the power generatedsupplied the loads. The mechanical part will be constructed as part of the energy source, thenwill be designed a control for controlling the power via electronic components, electrical loadssupplied by the system, will be simulated. To know the generated power to the control circuitwill install a meter and a serial communication device for communicating with a computer. It carries out a research on other systems and products in the Swedish market, to answer whetherthis system can be a backup system for electricity generation in small scale. The construction of a pedaling power system is achieved using a twelve volt direct currentmotor with permanent magnet as an energy source. System has the ability to show in an LCDdisplay and transmit through the serial ports, the value of the generated power. System canguide the power to the loads by using a microcontroller. Power generated by the system showedthat it is significant to be considered as an additional energy source, stand-alone or integratedwith other systems.
55

Lätt på foten : En självobservationsstudie i fottekniksövning med dubbelpedalspel på trummor / Find your feet : A self-observation study of foot-techinque execrises when playing the double pedal on drums

Kjellberg, Nils January 2018 (has links)
Syftet med arbetet är att jämföra två olika metoder för inlärning av fotteknik för spel vid trumset och hur de två olika metoderna påverkar trumspel. För att undersöka detta användes videoobservation samt loggbokförande under de sex veckor som undersökningsperioden varade. Varje vecka filmades tre olika övningstillfällen med varierande fokus. Studien grundar sig i det designteoretiska perspektivet. Resultatet av studien visade att olika metoder kan ge varierande resultat och att utforskandet av nya metoder kan ge positiva och oväntade resultat. Resultatet pekar även på att strategier och struktur ger positiva effekter vid övning. I diskussionsdelen diskuteras vilka resurser som varit mest givande för min utveckling samt hur en trummis måste vara medveten om sina begränsningar för att strategiskt kunna forma övning. / The purpose of this study is to compare two different methods of learning foot-technique and how the two methods affect playing of the drums. To examine this video-observation filled an important role with complement of a journal during the six weeks of practice that were recorded. Each week there were three videos recorded with variating focus each video. The study is based on design theory which is described in the background chapter. The result of this study showed that different methods can result in variating outcome and it also showed that exploring new methods can give positive effects on your practice. The discussion revolves around what resources have been the most impactful for my own personal development and how one must be conscious of one’s own limitations to be able to create a successful plan of practice.
56

Design, FEM strength analysis and testing of an innovative mountain bike pedal with magnetic locking mechanism

Jakel, Roland 24 May 2023 (has links)
The presentation describes the development of a new mountain bicycle pedal with a special magnetic safety locking mechanism by means of the finite element method (FEM). It starts with a description of the predecessor mountain bike pedal “Enduro” from magped GmbH and sets out the development objectives for the new pedal named “Enduro2”. The complete development activities like load determination and load assumptions, FEM analysis of the initial draft, subsequent optimization steps for strength improvement and mass reduction, bearing design and analysis, and prototype testing are described. The presentation ends with a chapter about creating computer generated images for marketing material of the pedal. The presentation is structured as follows: 1. Introduction: -Description of the predecessor mountain bike pedal “Enduro1” by magped GmbH -The magnetic safety locking mechanism -Overview of the magped GmbH product portfolio -Short magped GmbH company presentation -Development objectives and initial design draft of the successor pedal model “Enduro2” 2. Determination of the load cases for design & optimization: -Loads for bicycle pedals acc. to DIN ISO 4210 -Chosen load cases and qualification test program 3. Strength analysis and weight optimization of the pedal axis: -Pre-optimization steps -Optimized shape: Theoretical consideration of the pedal axis -Optimized design description -Obtained mass reduction -User tips for shape / notch stress optimization -Comparison with the axis of a competitor 4. Strength analysis and weight optimization of the pedal body: -Challenges in pedal body design -Computed load cases -Design result and mass savings 5. Bearing design and analysis: -Sliding bearing layout -Ball bearing layout: Bearing forces computation by FEM due to over-determined system -Description of the Creo Simulate FEM model -Bal bearing life span 6. Product testing: -Test program performed by the zedler-institute -Testing of the first test batch of pedals with hollow bored axis -Testing of the first test batch of pedals without hollow bored axis 7. Realized mass savings: -Magped Enduro1 and Enduro2 on the balance and comparison with the magped Gravel pedal 8. Creation of marketing material for the final product: -Still image creation -Photorealistic rendering containing FEM loading sequences / Der Vortrag beschreibt die Entwicklung eines neuen Mountainbike-Pedals mit einer speziellen magnetischen Sicherheitsverriegelung mittels der Finite-Elemente-Methode (FEM). Er beginnt mit einer Beschreibung des Vorgänger-Mountainbike-Pedals 'Enduro' der magped GmbH und legt die Entwicklungsziele für das neue Pedal mit dem Namen 'Enduro2' dar. Die gesamten Entwicklungsaktivitäten wie Lastermittlung und Lastannahmen, FEM-Analyse des ersten Entwurfs, nachfolgende Optimierungsschritte zur Festigkeitsverbesserung und Massenreduzierung, Lagerauslegung und -analyse sowie Prototypentests werden beschrieben. Die Präsentation endet mit einem Kapitel über die Erstellung computergenerierter Bilder für die Verwendung in Marketingmaterial des Pedals. Gliederung des Vortrages: 1. Einleitung: -Beschreibung des Vorgänger-Mountainbike-Pedals 'Enduro1' der magped GmbH -Die magnetische Sicherheitsverriegelung des Pedals -Überblick über das Produktportfolio der magped GmbH -Kurze Firmenpräsentation der magped GmbH -Entwicklungsziele und erster Designentwurf des Nachfolgemodells 'Enduro2' 2. Ermittlung der Lastfälle für Design & Optimierung: -Belastungsfälle für Fahrradpedale nach DIN ISO 4210 -Ausgewählte Lastfälle und Qualifikations-Testprogramm 3. Festigkeitsanalyse und Gewichtsoptimierung der Pedalachse: -Vor-Optimierungsschritte -Optimierte Form: Theoretische Betrachtung der Pedalachse -Beschreibung der optimierten Form -Erzielte Massenreduzierung -Anwendertipps zur Form- / Kerbspannungsoptimierung -Vergleich mit der Achse eines Wettbewerbers 4. Festigkeitsanalyse und Gewichtsoptimierung des Pedalkörpers: -Herausforderungen bei der Konstruktion von Pedalkörpern -Berechnete Lastfälle -Konstruktionsergebnis und Gewichtseinsparung 5. Lagerkonstruktion und -analyse: -Auslegung der Gleitlager -Auslegung der Kugellager: Berechnung der Lagerkräfte durch die FEM aufgrund des statisch überbestimmten Systems -Beschreibung des Creo Simulate FEM-Modells -Lebensdauer der Kugellager 6. Produktprüfung: -Testprogramm, durchgeführt durch das zedler-Institut -Erprobung der ersten Versuchscharge von Pedalen mit hohlgebohrter Achse -Prüfung der ersten Versuchscharge von Pedalen ohne hohlgebohrte Achse 7. Realisierte Masseneinsparung: -Magped Enduro1 und Enduro2 auf der Waage und Vergleich mit dem magped Gravel-Pedal 8. Erstellung von Marketingmaterial für das Endprodukt: -Erstellung von computergenerierten Fotos -Fotorealistisches Rendering mit FEM-Belastungssequenzen
57

Noise-free distortion pedal for electric guitars : Designing and constructing a unique distortion pedal for live playing guitarists

Almqvist, Tobias, Nordberg, David January 2019 (has links)
Guitarists using effect pedals to alter the way their guitar sounds often face the problem of loud noise when they want their guitars to be completely silent. This can be the result of using a distortion pedal which works well when you’re playing, but not when you have a brief pause. This project focuses on developing a complete prototype of a distortion pedal that has an adjustable mute circuit, also known as a noise gate, built into it. The project pedal consists of some functions which commercially available effect pedals have; 6.3 mm input jack, on and off switch, both a battery connector and a DC-jack, and adjustable knobs for the different effects like drive, tone and volume. The distortion circuit is inspired by the BOSS SD1 SUPER OVERDRIVE pedal and the muting function is constructed with Junction Field Effect Transistors.Two prototypes were constructed; one with hole mounted components, and one with surface mounted components. They both work largely as imagined. When the guitar is played, the desired distorted sound can be heard and adjusted with a drive, tone and volume control. When the guitar is not played, all unwanted noise is completely muted. A sensitivity adjusting knob allows for different signal strengths to be muted.The chosen method for muting the signal introduces a short and faint unwanted noise during the muting process. While it would have been better to eliminate this noise too, the prototype introduces something new and helpful for guitarists using distortion pedals. With more work, this way of integrating a mute circuit in distortion pedals could potentially set a new standard. / Gitarrister som använder effektpedaler för att ändra hur deras gitarr låter stöter ofta på problemet där oönskat brus uppstår när de vill att gitarren ska vara helt tyst. Detta kan vara resultatet av att använda en distortionspedal som fungerar väl när man spelar på gitarren, men inte när man tar en kort paus. Detta projekt fokuserar på att utveckla en fulländad prototyp av en distortionspedal som har en justerbar mutefunktion, också kallad en brusgrind. Pedalen har några funktioner som vanligtvis finns hos de kommersiellt tillgängliga pedalerna; 6.3 mm ingångsoch utgångskontakter, av-/påknapp, strömförsörjning via både ett batteri och vägguttag, och justerbara kontroller för förvrängning, ton och volym. Distortionskretsen är inspirerad av pedalen BOSS SD1 SUPER OVERDRIVE och mute-funktionen använder sig av Junction Field Effect Transistorer.Två prototyper konstruerades; en med hålmonterade komponenter, och en med ytmonterade komponenter. De både prototyperna fungerar i stort sett enligt de uppsatta målen. När gitarren spelas så hörs det önskade förvrängda ljudet som kan justeras med kontrollerna. När gitarren inte spelas dämpas allt oönskat brus till en ohörbar nivå. En känslighetskontroll tillåter olika signalstyrkor att tystas.Den valda metoden för mute-funktionen introducerar ett kort och svagt oönskat ljud som uppstår under själva dämpningsprocessen. Medan detta oljud är något som bör lösas så ger prototypen fortfarande något unikt och hjälpsamt för gitarrister. Med mer arbete skulle detta kunna förbli en ny standard inom distortionspedaler.
58

Where Have I Known This Before? An Exploration of Harmony and Voice Leading in the Compositions of Chick Corea

Lynch, Jordan 09 April 2012 (has links)
No description available.
59

Expanded tonality in three early piano works of Béla Bartók (1881-1945)

Brukman, Jeffrey James 11 1900 (has links)
Bart6k's own expanded tonal ("supradiatonic") pronouncements reveal that his music, notwithstanding tonally camouflaging surface details, clearly had a tonal foundation which in many respects is a reaction to the emerging atonalism of Schonberg. Analysis of three piano works (1908 - 1916) reveal that Bart6k's tonal language embraced intuitively the expanded tonal idiom. The harmonic resources Bart6k employed to obscure tonicisation embrace double-degree constructions, quartal formations, chords of addition and omission and other irregular constructions. Diatonic tonal pillars are evident in pedal points, tonic triads and dominant to tonic root movement. Through an application of the Riemann function theory expanded by Hartmann's supposition of fully-chromaticised scales tonal syntax (especially secondphase Strauss cadences or closes) becomes apparent within an expanded tonal product. The analyses conclude that Bart6k's inimitable "sound-world" is a twentieth-century manifestation of traditional tonality's primary tenets. / Musicology / M.Mus.
60

The Emergence of the Double-Action Harp as the Standard Instrument: Pleyel's Chromatic Harp and Erard's Double-Action Harp

Chen, Lee-Fei 22 May 2008 (has links)
The primary purpose of this essay is to provide comparisons between Pleyel's chromatic harp and Erard's double-action pedal harp, in order to find the factor leading to the emergence of the double-action harp as today's standard instrument. This essay includes biographies of Gustave Lyon and Sébastien Erard, historical background, literature, criticisms, influences, performance techniques and as well as musical examples demonstrating written techniques of Pleyel's chromatic harp and Erard's double-action pedal harp. In addition, this essay also includes a list of earlier twentieth-century works for the chromatic harp.

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