Spelling suggestions: "subject:"mecca"" "subject:"decay""
1 |
Radiobaserad positionering för UAV'erJakobsson, David, Jansson Stenroos, Erik January 2013 (has links)
Navigering med UAV:er kräver att farkostens och eventuellt ett måls position går att mäta ut under flygtillfället. I det allra flesta fall önskas en så hög noggrannhet som möjligt på positionen. DECCA är ett pensionerat system som var konstruerat för att läsa av fasförändringar mellan multiplar av en grundfrekvens. Systemet hade analoga mätare som gav utslag på förändringen av fasen och positionen kunde mätas ut på speciella kartor med inteferenslinjer som motsvarade en viss fasskillnad. GPS ger idag en precision ner på ett par meter, men med optimeringstekniker DGPS går det att komma ner i centimeternoggrannhet. Förutsättningen är att UAV:en befinner sig i ett geografiskt område med en minimal propagering på GPS-signalen. GPS är ett system som används idag och som fortfarande utvecklas. Fokus har lagts på att beskriva hur GPS går till väga för att få en hög precision på positioneringen och med de svårigheter som uppkommer med de långa avstånden mellan mottagaren och satelliten. En kort beskrivning över DECCA-systemets svagheter och styrkor ges, samt en kort sammanställning över hur DECCA och GPS skulle prestera i ett system med sändande antenner utplacerade över ett mindre geografisk område. / UAV navigation requires that the position of the vehicle and perhaps the destination to be measured, in flight. The reliability of close accuracy are in most case crucial for a positioning system. DECCA was constructed to measure the phase differences between several broadcasting frequencies, where all origin from one same fundamental frequency and broadcast as multiples of the source frequency. The system had analog meters which indicated the phase differences and with different interference lines corresponding to a certain phase different printed on a map, one could denote a rough position for the receiver. Today’s GPS grants accuracy within a few meter, but with technology as DGPS the precision can extend to a few centimetres. The condition for the precise position is where the GPS-signal are exposed for minimal propagation effects. Thus, the crucial is the receiver’s geographic location. Today GPS is active and used by numerous user around the world, but it is constant under development and improvement. The focal point has been to describe how GPS gets a good accuracy and the difficulties with the long distances between receiver and satellite. A short description over the weakness and strengths in DECCA has been made. And one short compilation over how well DECCA and GPS would perform in a system with multiple broadcast antennas, placed over a limited geographic area.
|
2 |
The Evolution of Ella Fitzgerald's Syllabic Choices in Scat Singing: A Critical Analysis of Her Decca Recordings, 1943-52Binek, Justin 05 1900 (has links)
This study examines the evolution of Ella Fitzgerald's scat syllable vocabulary during a key developmental period in her career when she was recording for Decca Records. Between 1943 and 1952, Fitzgerald established the syllabic vocabulary that would serve as a defining characteristic of her improvisational style for the rest of her career. Fitzgerald is commonly praised as the greatest vocal improviser in jazz history, but while much has been written about Fitzgerald's melodic and harmonic approach to jazz improvisation, little has been written about her syllabic approach. Timbre and articulation are considered to be vital elements of any jazz musician's style; the study examines the changes in Ella Fitzgerald's syllabic approach through transcription and analyses of thirteen scat solos recorded during this time period, using scat syllable choices to discuss timbre and articulation. This analysis provides a model for further research of its kind, as well as informing historically accurate performance practice by both teachers and students of jazz singing.
|
Page generated in 0.1391 seconds