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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.
21

Explaining and predicting the single channel versus multi-channel consumer : the case of an embarrassing product

Londono, Juan Carlos January 2013 (has links)
The fundamental purpose of this thesis was to determine how effective is the theory of planned behaviour (TPB) to predict and explain shopping for embarrassing products in single and multi-channel. This is important because multi-channel consumers buy more, the question is why (Neslin, Grewal et al. 2006). The question was answered by comparing consumer behaviour in three different channels: drugstore, internet and multi-channel. The Theory of Planned Behaviour (TPB) has been successful to predict intentions for a wide variety of products and behaviours. However, little is known about how effective it is when the behaviour under study is influenced by the emotion of embarrassment. Similarly, the TPB is parsimonious and has a good predictive power; nevertheless, this thesis identified that the TPB could be more effective if it considered: (1) the role of positive and negative emotions (2) other determinants of choice like personality and demographics (3) variables that are useful to make marketing decisions like the synergistic effect of brands, retailers and channels (4) variables that explain consumer response like approach and avoidance. To provide a comprehensive theoretical framework that is able to understand single and multi-channel, this thesis integrated the TPB within the Stimulus-Organism-Response (S-O-R) framework. To evaluate the proposed model, the study used a context and target product that resonated with the theory: the purchase of Regaine (a hair loss product that is embarrassing to buy) in Boots (a well-known UK. multi-channel drugstore). The embarrassing nature of Regaine created differences in the importance that variables play in each channel. The results were analysed using partial least squares structural equation modelling (PLS-SEM) and the three shopping environments were compared using multi-group analysis (MGA). The effectiveness of the TPB was improved. The variance explained (R² to intention) was 73 percent for the drugstore, 67 percent for the internet and 54 percent for multi-channel. However, subjective norm (SN) was the only factor that achieved significance for the three shopping environments. Personality and demographic factors had a low but significant moderating effect on intention. This thesis built on a series of contributions in different areas, such as the TPB, attitudes, subjective norm, perceived behavioural control, embarrassing products, multi-channel, marketing, emotions, personality and demographics. Future research should expand this thesis to other embarrassing products, industries and social media settings.
22

EXTRAÇÃO DE SINAIS DE VOZ EM AMBIENTES RUIDOSOS POR DECOMPOSIÇÃO EM FUNÇÕES BASES ESTATISTICAMENTE INDEPENDENTES / EXTRATION OF VOICE SIGNALS IN NOISY ENVIRONMENTS FOR DECOMPOSITION IN FUNCTIONS STATISTICAL INDEPENDENT BASES

Abreu, Natália Costa Leite 11 December 2003 (has links)
Made available in DSpace on 2016-08-17T14:52:55Z (GMT). No. of bitstreams: 1 Natalia Costa Leite Abreu.pdf: 841490 bytes, checksum: 00ff55b62f0819b502a66a2304564bf4 (MD5) Previous issue date: 2003-12-11 / The constant search for the improvement and strengthening of the relationship between humans and machines turning it more natural is common place. Consequently, the recognition of speech will turn, easier and practical the handling of equipments supplied with the capacity to understand the human speech. In this sense and with the use of the available knowledge information in the literature as how the human brain processes informations, some suggested methods try to simulate this ability in the computer, especially devoted to the extraction of a speech signal of mixed sounds, attempting, for example to increase the recognition and comprehension rate. The extraction of speech can be obtained by measures of a single-channel or multiple the channels. In order to extract the speech in a single channel, it is proposed here to use the speech characteristics introducing the concept of efficient codification, that tries to imitate the way the auditory cortex gets information using the method of Independent Component Analysis (ICA), getting the basis functions of the input signals and retrieving the estimated signal even when we add interferences to it. Our simulations also prove the efficiency of our method against reverberation effects and the recovery of speech signal by the handling of basis function of other speech signals. This technique can be used efficiently both to extract a single speech, as well as highlighting new ways of approaching the speech/speaker recognition problem. / A constante busca para aperfeiçoar e estreitar o relacionamento entre homens e máquinas, tornando-o mais natural, não é nenhuma novidade. Conseqüentemente, o reconhecimento da voz possibilitará uma manipulação mais fácil e prática de equipamentos dotados com a capacidade de compreender a fala humana. Neste sentido e utilizando-se dos conhecimentos disponíveis na literatura de como o cérebro humano processa informações, alguns métodos propostos procuram simular computacionalmente essa habilidade, voltados principalmente à extração de um sinal de voz de uma mistura de sons, na tentativa de, por exemplo, aumentar a taxa de reconhecimento e inteligibilidade. A extração da voz pode ser obtida usando medidas de um único ou múltiplos canais. Para extrair uma voz em um único canal, propomos usar as características da voz pelo conceito de codificação eficiente, que procura imitar o modo como o córtex auditivo trata as informações, utilizando-se da técnica de Análise de Componentes Independentes (ICA), obtendo as funções bases dos sinais de entrada e recuperando o sinal estimado, mesmo quando são adicionadas interferências. Através de simulações comprovamos também a eficiência da técnica usada, primeiro, na recuperação de um sinal de voz com a utilização das funções bases de outro sinal e, segundo, frente a efeitos de reverberação. Esta técnica pode ser usada para extrair uma única fala eficazmente, como também prenuncia um modo novo de chegar ao problema de reconhecimento da fala/orador.
23

Developing a portable, customizable, single-channel EEG device for homecare and validating it against a commercial EEG device / Utveckling av en portable, anpassningsbar, enkanalig EEG-enhet för hemsjukvård och dess validering gentemot en kommersiell EEG-enhet

Károly Tóth, Máté January 2023 (has links)
There are several commercial electroencephalography (EEG) devices on the market; however, affordable devices are not versatile for diverse research applications. The purpose of this project was to investigate how to develop a low-cost, portable, single-channel EEG system for a research institute that could be used for neurofeedback-related applications in homecare. A device comparison was intended to examine what system requirements such a system would need to achieve the secondary objective of developing a neurofeedback application that demonstrates the functionalities of the new device. A portable, single-channel EEG device prototype was realized that consisted of an amplifier module called EEG Click, a single-board microcontroller, an electrode cable, some disposable wet electrode pads, and a custom 3D-printed headband. Three pieces of software were developed: firmware for the prototype, two supporting computer applications for data recording, and visual neurofeedback. The neurofeedback application replayed a first-person view roller coaster video at a varying frame rate based on the theta band's mean power spectral density (PSD). The prototype was compared against a commercial device, InteraXon MUSE 2 (Muse). Technical measurements included determining the amplitude-frequency characteristics and signal quality, such as signal-to-noise ratio (SNR), spurious-free dynamic range (SFDR), and total harmonic distortion (THD). Furthermore, four physiological measurements were performed on six human test subjects, aged between 21-31 (mean: 26.0, std: 3.11), to compare the altered brain activity and induced artifacts between the two devices. The four tests were respiratory exercise, head movement exercise, eye movement exercise, and paced auditory serial addition test (PASAT), where each measurement included several epochs with various stimuli. After the recordings, PSD was calculated for each bandpass filtered epoch, then the spectra were split into theta (4-8 Hz), alpha (8-12 Hz), and beta bands (12-30 Hz). The PSD values were averaged within each frequency band, and then these baseline-corrected mean values were the input for the repeated measures ANOVA statistical analysis. Results revealed that the amplitude-frequency characteristic of the prototype was low-pass filter-like and had a smaller slope than Muse's. The prototype's SNR, including and excluding the first five harmonics, was 6 dB higher, while SFDR and THD for the first five harmonics were roughly the same as Muse's. The two devices were comparable in detecting changes in most physiological measurements. Some differences between the two devices were that Muse was able to detect changes in respiratory activity in the beta band (F(8,16) = 2.510, p = .056), while the prototype was more sensitive to eye movement, especially lateral and circular eye movement in theta (F(2,8) = 9.144, p = .009) and alpha (F(2,8) = 6.095, p = .025) bands. A low-cost, portable EEG prototype was successfully realized and validated. The prototype was capable of performing homecare neurofeedback in the theta band. The results indicated it is worth exploring further the capabilities of the prototype. Since the sample size was too small, more complex physiological measurements with more test subjects would be more conclusive. Nevertheless, the findings are promising; the prototype may become a product once. / Det finns flera kommersiella EEG-apparater (elektroencefalografi) på marknaden; däremot är de prismässigt överkomliga apparaterna inte mångsidiga nog för olika forskningsapplikationer. Syftet med detta projekt var att undersöka hur man kan utveckla en billigt, portabelt, enkanaligt EEG-system för ett forskningsinstitut som skulle kunna användas för neurofeedbackrelaterade tillämpningar inom hemsjukvård. En apparatjämförelse var tänkt att undersöka vilka systemkrav ett sådant system skulle behöva uppnå för att realisera det sekundära målet att utveckla en neurofeedback-applikation för att demonstrera den nya apparatens funktioner. En prototyp av en bärbar, enkanalig EEG-apparat skapades som bestod av en förstärkarmodul kallad EEG Click, en enkortsmikrokontroller, en elektrodkabel, några utbytbara våta elektrodkuddar och ett 3D-tryckt specialpannband. Tre mjukvarodelar utvecklades: en firmware för prototypen och två stödjande datorapplikationer, en för datainspelning och en för visuell neurofeedback. Applikationen för neurofeedback spelade upp en berg-och-dalbana för förstapersonsvisning med en varierande bildhastighet baserat på thetabandets effektspektrumet (eng. power spectral density, PSD). Prototypen jämfördes mot en kommersiell apparat, InteraXon MUSE 2 (Muse). Tekniska mätningar inkluderade fastställande av amplitud-frekvensegenskaper och signalkvalitet, såsom signal-brusförhållande (eng. signal-to-noise ratio, SNR), spuriosfritt dynamiskt område (eng. spurious free dynamic range, SFDR) och total harmonisk distorsion (eng. total harmonic distortion, THD). Vidare utfördes fyra fysiologiska mätningar på sex mänskliga deltagare (medelålder: 26,0, std: 3,11) för att jämföra de två apparaterna med avseende på mätningar av den förändrade hjärnaktiviteten och inducerade artefakter. De fyra testerna var andningsövningar, huvudrörelseövningar, ögonrörelseövningar, och paced auditory serial addition test (PASAT), där varje mätning innehöll flera epoker med olika stimuli. Efter inspelningarna beräknades PSD för varje bandpassfiltrerad epok, sedan delades spektrumet upp i theta-, alpha- och beta-band. Medelvärdet för PSD-värdena kalkylerades för varje frekvensband och dessa baseline-korrigerade medelvärden var indata till den beroende ANOVA statistisk analysen. Resultaten avslöjade att amplitud-frekvenskarakteristiken för prototypen var lågpassfilterliknande och hade en mindre lutning än Muses. Prototypens SNR, inklusive och exklusive de första fem harmonik, var 6 dB högre, medan SFDR och THD för de första fem övertonerna var ungefär desamma som Muses. De två apparaterna var jämförbara när det gäller att upptäcka förändringar i de flesta fysiologiska mätningar. Vissa skillnader mellan de två apparaterna var att Muse kunde upptäcka förändringar i andningsaktivitet i beta-bandet (F(8,16) = 2,510, p = 0,056), medan prototypen var mer känslig för ögonrörelser, särskilt de laterala och cirkulära ögonrörelser, i theta-bandet (F(2,8) = 9,144, p = 0,009) och alfa-bandet (F(2,8) = 6,095, p = 0,025). Prototypen var generellt mer känslig för grundläggande hjärnaktivitet, buller från omgivningen och artefakter. Sammanfattningvis konstruerades en billig, bärbar EEG-prototyp, vilketvaliderades framgångsrikt. Den anpassade enheten kunde utföra neurofeedback för hemsjukvård. Resultaten visade att det är värt att utforska prototypens möjligheter ytterligare. Eftersom stickprovet var relativt litet skulle mer komplexa fysiologiska mätningar med flera testpersoner krävas för att fastställa framtida användningsområden. Icke desto mindre är resultaten lovande; prototypen kan bli en produkt en gång.
24

Imaging the assembly of the Staphylococcal pore-forming toxin alpha-Hemolysin

Thompson, James Russell January 2009 (has links)
Alpha-hemolysin is a pore-forming toxin secreted by pathogenic Staphylococcus aureus. Its spontaneous oligomerization and assembly into a trans-bilayer beta-barrel pore is a model for the assembly of many other pore-forming toxins. It is studied here in vitro as a means to probe general membrane protein oligomerization and lipid bilayer insertion. This thesis details the results of experiments to develop and implement a novel in vitro lipid bilayer system, Droplet-on-Hydrogel Bilayers (DHBs) for the single-molecule imaging of alpha-hemolysin assembly. Chapter 2 describes the development of DHBs and their electrical characterization. Experiments show the detection of membrane channels in SDS-PAGE gels post-electrophoresis and DHBs use as a platform for nanopore stochastic sensing. Chapter 3 describes the engineering and characterization of fluorescently-labelled monomeric alpha-hemolysin for use in protein assembly imaging experiments described in Chapter 6. Chapter 4 describes the characterization of DHB lipid fluidity and suitability for single-molecule studies of membrane protein diffusion. In addition, a novel single-particle tracking algorithm is described. Chapter 5 describes experiments demonstrating simultaneous electrical and fluorescence measurements of alpha-hemolysin pores embedded within DHBs. The first multiple-pore stochastic sensing in a single-lipid bilayer is also described. Chapter 6 describes experiments studying the assembly of alpha-hemolysin monomers in DHBs. Results show that alpha-hemolysin assembles rapidly into its oligomeric state, with no detection of long-lived intermediate states.
25

Integration von Connexonen in Lipidmembranen auf porösen Oberflächen / Integration of connexons in lipid bilayers on porous substrates

Gaßmann, Helmut Albin Oliver 15 July 2010 (has links)
No description available.
26

Preamplifier Design for Active Electrodes in Single-Channel EEG Applications

Marwan Abed, Thorir January 2018 (has links)
The implementation of portable electroencephalography (EEG) systems has been known to be complex. During ambulation, the integrity of recorded EEG signals is often impaired by motion artifacts and the time and effort required to set up the system is excessive. The use of single-channel EEG systems with dry, active electrodes (AEs) for signal acquisition is a topic of current interest. AEs are electrodes which have integrated bioamplifier circuitry and are known to be less susceptible to motion artifacts and environmental interference. In this report, the design of an AE preamplifier for the purpose of improving single-channel EEG recordings is presented. Initially, a thorough literature review was performed, exploring the available knowledge and state-of-the-art technology. Thereafter, the design specifications were set and the appropriate topology and circuit design techniques were selected to maximize the amplifier’s performance. Ultimately, three different preamplifier topologies were designed and their performance compared with one another as well as with established medical device standards and state-of-the-art AEs. The results of one preamplifier showed comparable performance with state-of-the-art AEs. Therefore, this topology was selected for a deep analysis and physical layout design. The layout of the selected preamplifier was designed and its parasitics extracted. The post layout performance of the design proved to be comparable to the schematic level performance, with a CMRR of 153dB, IRNV of 0.89µVRMS and an electrode offset tolerance of 450mV. The preamplifier design presented in this report has proven to be comparable with state-of-the-art AE preamplifiers and demonstrates potential for the advancement of AE performance in single-channel EEG systems. / Implementeringen av bärbara elektroencefalografisystem (EEG) har varit känd för att vara komplex. Vid rörelse påverkas ofta reliabiliteten av de inspelade EEGsignalerna av rörelseartefakter samt av att tiden och det arbete som krävs för att ställa in systemet blir överdrivet lång. Användandet av singelkanals EEG-system, med torra aktiva elektroder (AE) under inspelningen, är ett aktuellt ämne. En AE är en elektrod som har en integrerad bioförstärkarkrets och är känd för att vara både mindre mottaglig för rörelseartefakter och för störning från omgivningen. I denna rapport presenteras utformningen av en AE-förförstärkare för singelkanals EEGinspelningar. Inledningsvis utfördes en grundlig litteraturöversikt där den rådande kunskapen och toppmoderna tekniken undersöktes. Därefter bestämdes designspecifikationerna, lämpliga topologier samt kretsdesigntekniker, för att maximera förstärkarens prestanda. Slutligen konstruerades tre olika förstärkares topologier och deras prestanda jämfördes med varandra liksom med etablerade medicin tekniska standarder och toppmoderna AE. Resultaten av en förförstärkare visade sig ha jämförbar prestanda med toppmoderna AE. Därför valdes denna topologi ut för en djupanalys och för fysisk layoutkonstruktion. Layouten för den valda förförstärkaren utformades och dess parasiter extraherades. Utformningen av postlayouten visade sig vara jämförbar med prestanda på en schematisk nivå, med en CMRR på 153dB, IRNV på 0.89µVRMS och en elektrodoffsettolerans på 450mV. Förförstärkarens design som presenteras i denna rapport har visat sig vara jämförbar med toppmoderna AE-förförstärkare och visar potential till framsteg för AEprestanda i singelkanals EEG-system
27

Evaluation of Methods for Sound Source Separation in Audio Recordings Using Machine Learning

Gidlöf, Amanda January 2023 (has links)
Sound source separation is a popular and active research area, especially with modern machine learning techniques. In this thesis, the focus is on single-channel separation of two speakers into individual streams, and specifically considering the case where two speakers are also accompanied by background noise. There are different methods to separate speakers and in this thesis three different methods are evaluated: the Conv-TasNet, the DPTNet, and the FaSNetTAC.  The methods were used to train models to perform the sound source separation. These models were evaluated and validated through three experiments. Firstly, previous results for the chosen separation methods were reproduced. Secondly, appropriate models applicable for NFC's datasets and applications were created, to fulfill the aim of this thesis. Lastly, all models were evaluated on an independent dataset, similar to datasets from NFC. The results were evaluated using the metrics SI-SNRi and SDRi. This thesis provides recommended models and methods suitable for NFC applications, especially concluding that the Conv-TasNet and the DPTNet are reasonable choices.
28

Koöperasie as mededingingstrategie vir graanprodusente, 1995

Olivier, Pieter Gerhardus 06 1900 (has links)
Kooperasies, as werktuie ter doelwitbereiking vir graanprodusente, het sedert hul totstandkoming onderskeibare ontwikkelingsfases deurgegaan. Die toepassing van kooperasie as mededingingstrategie deur graanprodusente is grootliks bei"nvloed deur die veranderings wat tydens die ontwikkelingsfases voorgekom het. Aksies wat in die loop van hierdie ontwikkellngsfases ingestel was, het mettertyd onduidelikhede oor die bestaansgrondslag van die kooperasies laat ontstaan. Die klJmaat van politieke veranderings wat tans in die land heers, kan ook belangrike veranderings meebring ten opsigte van die grondslag waarop kooperasies funksioneer. Pie uitwerking van die verwagte veranderings kan kooperasies forseer om strategiese aanpassings in hul strukture te maak ten einde steeds suksesvol te kan bly voortbestaan. · Graanprodusente verkeer in 'n posisie wat vereis dat daar besin moet word oor strategiee wat gevolg kan word ten einde steeds suksesvol in die onsekere markomstandighede mee te ding. Die toepassing van kooperasie as mededingingstrategie waarvolgens graanprodusente deur lidmaatskap van die kooperasies in die mark deelgeneem het, kom nou ook onder die loep. Die hoofprobleem waarop daar dus in hierdie studie gefokus word, is om te bepaal of kooperasie as mededingingstrategie geskik is om die individuele en kollektiewe belange van graanprodusente te bevorder. Van die belangrikste bevindings van die studie is: Graanprodusente voorsien dat kooperasie individuele graanprodusente se markoptrede kan versterk. Graanprodusente is van mening dat hulle deur middel van kooperasie wat manifesteer in selfstandige besigheidsondernemings, genaamd ''kooperasies", 'n positiewe invloed vir graanprodusente op die mark kan uitoefen. Daar kcan nie 'n beduidende negatiewe, of positiewe persepsie oor onderlinge mededinging en die invloed wat die vryemarkbedeling daarop uitoefen, by graanprodusente gei"dentifiseer word nie. Dit blyk egter dat sommige graanprodusente die vryemarkbedeling as 'n belangrike markfaktor bejeen. Ander graanprodusente huldig 'n meer buigsame benadering jeens die vryemarkbedeling. Graanprodusente is, met enkele klemverskille, van mening dat die kooperasies nie daarin slaag om die tradisionele kooperasiebeginsels in die wyse waarop kooperasies hul besigheid bedryf, volledig toe te pas nie. Graanprodusente het oor die algemeen gesien duidelike menings oor die noodsaaklikheid daa.rvan dat die staat nie by die graanbedryf meet inmeng nie. Ander tipes ondersteuningstrategiee, soos die oprigting van beslote korporasies of maatskappye, geniet wisselende steun. 'n Beduidende groep graanprodusente is onseker oor moontlikhede om maatskappye met kapitaalgroei as basis te skep, om sodoende in geheel met kooperasies weg te doen. / Co-operatives have experienced distinguishable changes. The application of co-operation as a competitive strategy by g~in producers was largely influenced by the changes. The prevailing political changes can also instigate important changes with regard to co-operatives. Grain producers must revise strategies to maintain successful competition in the market. The study investigates co-operation as a competitive strategy to advance the individual and collective interests of grain producers, Findings are: Grain producers are convinced that co-operation enhances the market related actions of individual grain producers. Grain producers can, through co-operation, exercise a positive influence in the market. No definite negative or positive perception concerning the influence of the free market system upon mutual competition could be identified. Grain producers are convinced that the state should not interfere with the grain industry. / Business Management / M. Admin. (Business Management)
29

Seismic structure, gas hydrate, and slumping studies on the Northern Cascadia margin using multiple migration and full waveform inversion of OBS and MCS data

Yelisetti, Subbarao 05 November 2014 (has links)
The primary focus of this thesis is to examine the detailed seismic structure of the northern Cascadia margin, including the Cascadia basin, the deformation front and the continental shelf. The results of this study are contributing towards understanding sediment deformation and tectonics on this margin. They also have important implications for exploration of hydrocarbons (oil and gas) and natural hazards (submarine landslides, earthquakes, tsunamis, and climate change). The first part of this thesis focuses on the role of gas hydrate in slope failure observed from multibeam bathymetry data on a frontal ridge near the deformation front off Vancouver Island margin using active-source ocean bottom seismometer (OBS) data collected in 2010. Volume estimates (∼ 0.33 km^3) of the slides observed on this margin indicate that these are capable of generating large (∼ 1 − 2 m) tsunamis. Velocity models from travel time inversion of wide angle reflections and refractions recorded on OBSs and vertical incidence single channel seismic (SCS) data were used to estimate gas hydrate concentrations using effective medium modeling. Results indicate a shallow high velocity hydrate layer with a velocity of 2.0 − 2.1 km/s that corresponds to a hydrate concentration of 40% at a depth of 100 m, and a bottom simulating reflector (BSR) at a depth of 265 − 275 m beneath the seafloor (mbsf). These are comparable to drilling results on an adjacent frontal ridge. Margin perpendicular normal faults that extend down to BSR depth were also observed on SCS and bathymetric data, two of which coincide with the sidewalls of the slump indicating that the lateral extent of the slump is controlled by these faults. Analysis of bathymetric data indicates, for the first time, that the glide plane occurs at the same depth as the shallow high velocity layer (100±10 mbsf). In contrast, the glide plane coincides with the depth of the BSR on an adjacent frontal ridge. In either case, our results suggest that the contrast in sediments strengthened by hydrates and overlying or underlying sediments where there is no hydrate is what causing the slope failure on this margin. The second part of this dissertation focuses on obtaining the detailed structure of the Cascadia basin and frontal ridge region using mirror imaging of few widely spaced OBS data. Using only a small airgun source (120 cu. in.), our results indicate structures that were previously not observed on the northern Cascadia margin. Specifically, OBS migration results show dual-vergence structure, which could be related to horizontal compression associated with subduction and low basal shear stress resulting from over-pressure. Understanding the physical and mechanical properties of the basal layer has important implications for understanding earthquakes on this margin. The OBS migrated image also clearly shows the continuity of reflectors which enabled the identification of thrust faults, and also shows the top of the igneous oceanic crust at 5−6 km beneath the seafloor, which were not possible to identify in single-channel and low-fold multi-channel seismic (MCS) data. The last part of this thesis focuses on obtaining detailed seismic structure of the Vancouver Island continental shelf from MCS data using frequency domain viscoacoustic full waveform inversion, which is first of its kind on this margin. Anelastic velocity and attenuation models, derived in this study to subseafloor depths of ∼ 2 km, are useful in understanding the deformation within the Tofino basin sediments, the nature of basement structures and their relationship with underlying accreted terranes such as the Crescent and the Pacific Rim terranes. Specifically, our results indicate a low-velocity zone (LVZ) with a contrast of 200 m/s within the Tofino basin sediment section at a depth 600 − 1000 mbsf over a lateral distance of 10 km. This LVZ is associated with high attenuation values (0.015 − 0.02) and could be a result of over pressured sediments or lithology changes associated with a high porosity layer in this potential hydrocarbon environment. Shallow high velocities of 4 − 5 km/s are observed in the mid-shelf region at depths > 1.5 km, which is interpreted as the shallowest occurrence of the Eocene volcanic Crescent terrane. The sediment velocities sharply increase about 10 km west of Vancouver Island, which probably corresponds to the underlying transition to the Mesozoic marine sedimentary Pacific Rim terrane. High attenuation values of 0.03 − 0.06 are observed at depths > 1 km, which probably corresponds to increased clay content and the presence of mineralized fluids. / Graduate / 0373 / 0372 / 0605 / subbarao@uvic.ca
30

Koöperasie as mededingingstrategie vir graanprodusente, 1995

Olivier, Pieter Gerhardus 06 1900 (has links)
Kooperasies, as werktuie ter doelwitbereiking vir graanprodusente, het sedert hul totstandkoming onderskeibare ontwikkelingsfases deurgegaan. Die toepassing van kooperasie as mededingingstrategie deur graanprodusente is grootliks bei"nvloed deur die veranderings wat tydens die ontwikkelingsfases voorgekom het. Aksies wat in die loop van hierdie ontwikkellngsfases ingestel was, het mettertyd onduidelikhede oor die bestaansgrondslag van die kooperasies laat ontstaan. Die klJmaat van politieke veranderings wat tans in die land heers, kan ook belangrike veranderings meebring ten opsigte van die grondslag waarop kooperasies funksioneer. Pie uitwerking van die verwagte veranderings kan kooperasies forseer om strategiese aanpassings in hul strukture te maak ten einde steeds suksesvol te kan bly voortbestaan. · Graanprodusente verkeer in 'n posisie wat vereis dat daar besin moet word oor strategiee wat gevolg kan word ten einde steeds suksesvol in die onsekere markomstandighede mee te ding. Die toepassing van kooperasie as mededingingstrategie waarvolgens graanprodusente deur lidmaatskap van die kooperasies in die mark deelgeneem het, kom nou ook onder die loep. Die hoofprobleem waarop daar dus in hierdie studie gefokus word, is om te bepaal of kooperasie as mededingingstrategie geskik is om die individuele en kollektiewe belange van graanprodusente te bevorder. Van die belangrikste bevindings van die studie is: Graanprodusente voorsien dat kooperasie individuele graanprodusente se markoptrede kan versterk. Graanprodusente is van mening dat hulle deur middel van kooperasie wat manifesteer in selfstandige besigheidsondernemings, genaamd ''kooperasies", 'n positiewe invloed vir graanprodusente op die mark kan uitoefen. Daar kcan nie 'n beduidende negatiewe, of positiewe persepsie oor onderlinge mededinging en die invloed wat die vryemarkbedeling daarop uitoefen, by graanprodusente gei"dentifiseer word nie. Dit blyk egter dat sommige graanprodusente die vryemarkbedeling as 'n belangrike markfaktor bejeen. Ander graanprodusente huldig 'n meer buigsame benadering jeens die vryemarkbedeling. Graanprodusente is, met enkele klemverskille, van mening dat die kooperasies nie daarin slaag om die tradisionele kooperasiebeginsels in die wyse waarop kooperasies hul besigheid bedryf, volledig toe te pas nie. Graanprodusente het oor die algemeen gesien duidelike menings oor die noodsaaklikheid daa.rvan dat die staat nie by die graanbedryf meet inmeng nie. Ander tipes ondersteuningstrategiee, soos die oprigting van beslote korporasies of maatskappye, geniet wisselende steun. 'n Beduidende groep graanprodusente is onseker oor moontlikhede om maatskappye met kapitaalgroei as basis te skep, om sodoende in geheel met kooperasies weg te doen. / Co-operatives have experienced distinguishable changes. The application of co-operation as a competitive strategy by g~in producers was largely influenced by the changes. The prevailing political changes can also instigate important changes with regard to co-operatives. Grain producers must revise strategies to maintain successful competition in the market. The study investigates co-operation as a competitive strategy to advance the individual and collective interests of grain producers, Findings are: Grain producers are convinced that co-operation enhances the market related actions of individual grain producers. Grain producers can, through co-operation, exercise a positive influence in the market. No definite negative or positive perception concerning the influence of the free market system upon mutual competition could be identified. Grain producers are convinced that the state should not interfere with the grain industry. / Business Management / M. Admin. (Business Management)

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