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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.
71

Just diagonalize: a curvelet-based approach to seismic amplitude recovery

Herrmann, Felix J., Moghaddam, Peyman P., Stolk, Christiaan C. January 2007 (has links)
No description available.
72

The distribution and synopsis of ecological and silvical characteristics of tree species of British Columbia's forests

Klinka, Karel, Worrall, John, Skoda, L., Varga, Pal, Chourmouzis, Christine January 1999 (has links)
An updated silvics text for British Columbia. The need for an effective learning tool for silvics - one of the basic required courses in forestry - has been recognized by intructors as well as students across the province. The text prepared 18 years ago by Krajina et al. (1982) specifically for western Canada has become outdated. The silvics text by Burns and Honkala (1990) represents an up-to-date compendium but it is not an effective learning tool, particularly lacking in the linkage of silvics to ecological classification. Consequently, we revised and expanded “Distribution and Ecological Characteristics of Trees and Shrubs of British Columbia” (Krajina et al. 1982) using the available information on silvics, with some modification for BC and the results of recent silvics research done in BC. This material has been consolidated into a format that will help students understand the silvical attributes of tree species as well as the relationships between trees and their environments. To enhance learning, we have selected a series of slides illustrating the salient characteristics for each species and present this visual component on a CD-ROM included with the text. Also included is a large biogeoclimatic zone map of BC. The text, together with the CD-ROM, is intended to facilitate learning of silvics emphasizing its application to silviculture.
73

Turbo coded pulse position modulation for optical communications

Alahmari, Abdallah Said 05 1900 (has links)
No description available.
74

Effects of the prominence of first harmonic on the perception of breathiness and vowel identity.

Sloane, Samuel David January 2013 (has links)
Title:EFFECTS OF THE PROMINENCE OF FIRST HARMONIC ON THE PERCEPTION OF BREATHINESS AND VOWEL IDENTITY Authors: Emily Lin, Samuel Sloane,and Donal Sinex Background: Human communication relies on adequate speech intelligibility to enable the comprehension of verbal messages. Dysphonia (i.e., aberrant voice) may not only result in distraction during communication but also interfere with speech intelligibility leading to a communication barrier. One voice quality commonly found in dysphonia is breathiness, which is related to the presence of excessive airflow during phonation due to incomplete glottal closure. Breathiness has been associated with the prominence of the first harmonic (H1) in the acoustic analysis of voice. Objectives: This study aimed to determine whether excessiveness in the first harmonic (H1) dominance, which has been associated with breathy voice, may result in the perception of breathiness and compromise vowel intelligibility. Methods: Participants included 10 female and 10 male normal-hearing adults, aged between 19 to 40 years. Participant’s tasks included a “breathiness rating” and a “vowel identification” task. For the “breathiness rating” task, a direct magnitude method was employed for the participant to rate a 500-ms long vowel (/i/ and /a/) segmented from sustained vowel phonation. For the “vowel identification” task, the vowel stimuli were segmented out from running speech (“Rainbow passage”) and the participants were asked to listen to one vowel stimulus (/i/, /a/, or /o/; duration: 60 ms) at a time and indicate which vowel (i.e., /i/, /e/, /a/, /o/, or /u/) they perceived the stimulus to be. The vowel stimuli included processed and unprocessed voice recordings of individuals with and without voice disorders. Voices showing the lowest, median, and highest amplitude differences between the first two harmonics (H1-H2) were chosen from a voice database for female and male voices respectively. The 18 selected vowel signals (3 vowels X 3 H1-H2 levels X 2 speaker genders) were processed through 12 signal manipulation conditions. The 12 signal conditions involved increasing or decreasing the H1 amplitude of the original signals in six 2-dB interval steps in both directions. Results: For the “breathiness rating” task, the five-way (3 vowels X 2 speaker genders X 3 H1-H2 levels X 13 signal conditions X 2 listener genders) Mixed Model Analysis of variance (ANOVA) conducted on the breathiness scores for normal speakers and voice patients separately showed significant findings for various main and interaction effects, such as a significant speaker gender by signal condition by vowel interaction effect on the perception of breathiness [F(12, 96) = 1.95, p = 0.038] for normal voice. An increase of H1-H2 through signal manipulation led to an increase of perceived breathiness only when performed on the vowel /i/ produced by female normal speakers. As for the “vowel identification” task, a relationship between H1-H2 increment and vowel intelligibility was found but the relationship was affected by vowel type, speaker gender, and H1-H2 level. With all vowel types, speaker genders, and H1-H2 levels combined, a significant signal condition effect on the number of incorrect vowel identification was found (2 = 188.585, df = 10, p < 0.001). Generally, it appeared that an increase of H1-H2 would worsen the identification of /i/ but enhance that of /o/. Conclusion: The relationship between H1 dominance and perceived breathiness was non-linear. Factors found to disrupt the linear relationship included speaker gender, vowel type, and the extent of H1 dominance. In addition, there was evidence that acoustic manipulation of the H1 amplitude would affect vowel intelligibility and the relationship between vowel intelligibility and H1-H2 values also vary by speaker genders and vowel types.
75

Integruotos amplitudės EEG (aEEG) metodo taikymas miego pradžiai aptikti / Use of amplitude integrated - method (aeeg) for sleep onset detection

Žukauskaitė, Rasa 26 June 2014 (has links)
Sveikas žmogus užmiega vidutiniškai per 15 min, o miegas prasideda lėtojo miego fazėje. Patologinis užmigimas yra diagnozuojamas narkolepsija sergantiems pacientams, kurie užmiega paradoksinio miego fazėje. Šiam miego sutrikimui diagnozuoti yra atliekamas - Pakartotinas Miego Latencijos Testas (anlg. Multiply sleep latency test (MSLT)). Testas atliekamas tam pačiam pacientui keturis kartus per dieną. Vertinamos keturios užmigimo trukmės, analizuojant registruojamą paciento žievės bioelektrinį aktyvumą polisomnografiniu tyrimu miego laboratorijoje bei vertinant miego latenciją. Miegas ir epilepsija yra susiję. Miego metu provokuojami priepuoliai, tuo tarpu priepuoliai įtakoja miego vientisumą, jo fazes. Kai kurių epilepsijos formų (idiopatinės židininės, infantilinių spazmų ir kt.) epilepsiniai priepuoliai aktyvuojasi užmingant, kitų (juvenilinės miokloninės)- prabundant. Miego pradžios nustatymas yra reikalingas epilepsija sergančių ligonių miego struktūros analizei, ankstyvųjų epilepsinių iškrūvių atpažinimui bei tiksliai narkolepsijos diagnostikai. Todėl klinikinėje praktikoje yra reikalingas automatinis diagnostinis metodas, kuris padėtų objektyviai, greitai ir tiksliai įvertinti miego pradžią. Mūsų tyrimo tikslas - įvertinti integruotos amplitudės EEG (aEEG) metodo patikimumą nustatant miego pradžią narkolepsija ir epilepsija sergantiems pacientams Tyrime dalyvavo Kopenhagos universitetinėje ligoninėje gydyti 25 narkolepsija sergantys bei 23 Vilniaus universiteto vaikų... [toliau žr. visą tekstą] / The onset of sleep under normal circumstances in young adult humans is normally through Non-REM sleep after 15 minutes of being awake. The abnormal entry into sleep through REM sleep can be diagnostic in patients with narcolepsy. One important investigation in diagnosing narcolepsy is the Multiple Sleep Latency Test (MSLT), where onset of sleep and occurrence of REM – if any is measured 4 times per day. This test is traditionally scored by visual analysis of sleep onset and onset of REM sleep. There is tight relation between sleep and epilepsy. During sleep epileptiform activity is frequent and seizures make influence on the quality of sleep ant it’s phases. In some types of epilepsy (e.g. idiopathic focal) seizures occur during onset of sleep, in others (juvenile myoclonic) – short time after awaking. Detection of sleep onset is very important for the evaluation of the sleep quality of epilepsy patient’s and for accurate diagnosis of narcolepsy. EEG interpretation strongly depends on the skills of the EEG reader. Therefore automatic sleep onset detection could be useful diagnostic tool for EEG interpretation. We have found it of interest to investigate if an automatic analysis amplitude – integrated electroencephalography (aEEG) method could reliable identify sleep onset by comparing it with visual analysis in 25 narcolepsy patients, who were treated in Copenhagen University hospital and 23 children with epilepsy (idiopathic focal and juvenile myoclonic), who were treated in... [to full text]
76

Analysis of frequency conversion for M-QAM and M-PSK modems

Wojtiuk, Jeffrey John Unknown Date (has links)
Thesis (M.Eng.)--University of South Australia, 1995
77

Analysis of frequency conversion for M-QAM and M-PSK modems

Wojtiuk, Jeffrey John Unknown Date (has links)
Thesis (M.Eng.)--University of South Australia, 1995
78

True amplitude prestack depth migration /

Deng, Feng, January 2007 (has links)
Thesis (Ph.D.)--University of Texas at Dallas, 2007. / Includes vita. Includes bibliographical references (leaves 103-107)
79

1/f AM and PM noise in a common source heterojunction field effect transistor amplifier

Cardon, Christopher Don. January 2007 (has links)
Thesis (M.S.)--University of Wyoming, 2007. / Title from PDF title page (viewed on July 28, 2008). Includes bibliographical references (p. 61-62).
80

Regularization of the AVO inverse problem by means of a multivariate Cauchy probability distribution

Alemie, Wubshet M. January 2010 (has links)
Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on Mar. 18, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Geophysics, Department of Physics, University of Alberta. Includes bibliographical references.

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