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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

The impact of sponsorship announcements on share prices in South Africa

Kruger, Thomas Stephanus 14 July 2012 (has links)
Much has been written, by academics, about the impact sponsorship announcements have on the share price performance of sponsoring firms. The objective of this study was to investigate if this phenomenon was true for JSE listed companies with particular focus on three announcement categories i.e. (i) new, (ii) renew and (iii) termination. The Efficient Market Hypothesis as an aspect of Investment Finance behaviour was explored to understand why sponsorship announcements would or would not have an impact on the share price performance. For this study, descriptive research was done with a causal design as the study tested the relationship between two or more variables. The study analysed 118 sponsorship announcements made by 19 JSE listed companies over a period of eleven years and five months. The study then assessed the share price performance for the period 120 days prior to and 120 days after the announcement date. The share price holding periods were adjusted for that of the average Financial Services (J212) Index, the Industrial (J212) Index and the Resources (J258) Index respectively to ascertain whether the returns were abnormal or not. The results have shown that there were no evidence that the announcement of a (i) new, (ii) renewed or (iii) terminated sponsorship do have a significant impact on the performance of share prices for JSE listed companies. / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted
72

Thermal comfort study on a renovated residential apartment in Tjärna Ängar, Borlänge

Mnla Ali, Tammam January 2021 (has links)
The Swedish government in the 1960th initiated “The Million Program” to build million residentialunits to cover the housing shortage between 1965 to 1975. Tjärna Ängar neighborhood in Borlängemunicipality was built during the million-program period, where these residential units became old,and the indoor environment is uncomfortable for the residents.Recently, there have been extensive energy-efficient renovations to improving the energyefficiency,indoor air quality, and thermal comfort of these buildings. The renovation project, withcooperation between Dalarna University and the local housing company (Stora Tunabyggen)started in 2015 by renovating three buildings in the Tjärna Ängar neighborhood.This study was conducted at one of these three retrofitting buildings (Kornstigen 25) to investigatethe thermal comfort in the building following energy retrofit. The assessment of the thermalcomfort in this study is based on Fanger's model with the use of predicted mean vote (PMV) andpredicted percentage of dissatisfied (PPD) to assess the obtained measurements.An online questionnaire survey with building occupants was conducted to give a betterunderstanding of the current situation of the retrofitting building before and after the renovationregarding thermal comfort. Based on the measurement, the thermal sensation of the occupants isslightly cool according to the standard’s sensation scale during the period of the measurement. Anonline questionnaire survey assures that the occupants were feeling slightly cool during someperiods of the day inside the apartments.
73

Accelerating Multi-target Visual Tracking on Smart Edge Devices

Nalaie, Keivan January 2023 (has links)
\prefacesection{Abstract} Multi-object tracking (MOT) is a key building block in video analytics and finds extensive use in surveillance, search and rescue, and autonomous driving applications. Object detection, a crucial stage in MOT, dominates in the overall tracking inference time due to its reliance on Deep Neural Networks (DNNs). Despite the superior performance of cutting-edge object detectors, their extensive computational demands limit their real-time application on embedded devices that possess constrained processing capabilities. Hence, we aim to reduce the computational burdens of object detection while maintaining tracking performance. As the first approach, we adapt frame resolutions to reduce computational complexity. During inference, frame resolutions can be tuned according to the complexity of visual scenes. We present DeepScale, a model-agnostic frame resolution selection approach that operates on top of existing fully convolutional network-based trackers. By analyzing the effect of frame resolution on detection performance, DeepScale strikes good trade-offs between detection accuracy and processing speed by adapting frame resolutions on-the-fly. Our second approach focuses on enhancing the efficiency of a tracker by model adaptation. We introduce AttTrack to expedite tracking by interleaving the execution of object detectors of different model sizes in inference. A sophisticated network (teacher) runs for keyframes only while, for non-keyframe, knowledge is transferred from the teacher to a smaller network (student) to improve the latter’s performance. Our third contribution involves exploiting temporal-spatial redundancies to enable real-time multi-camera tracking. We propose the MVSparse pipeline which consists of a central processing unit that aggregates information from multiple cameras (on an edge server or in the cloud) and distributed lightweight Reinforcement Learning (RL) agents running on individual cameras that predict the informative blocks in the current frame based on past frames on the same camera and detection results from other cameras. / Thesis / Doctor of Science (PhD)
74

Computer simulation of the dynamics and control of an energy-efficient robot leg

Cheng, Fan-Tien January 1982 (has links)
No description available.
75

Multiple-Input Multiple-Output Systems for Spinning Vehicles

Petersen, Samuel 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / This paper investigates the performance of a multiple-input multiple-output (MIMO) digital communication system, when the transmitter is located on a spinning vehicle. In particular, a 2x2 MIMO system is used, with Alamouti coding at the transmitter. Both Rayleigh and Rayleigh plus line-of-sight, or Rician, models combined with a deterministic model to simulate the channel. The spinning of the transmitting vehicle, relative to the stationary receive antennas, modulates the signal, and complicates the decoding and channel parameter estimation processes. The simulated system bit error rate is the primary performance metric used. The Alamouti channel code is shown to perform better than the maximal ratio receiver combining (MRRC) and single receiver (2x1) system in some circumstances and performs similarly to the MRRC in the broadside case.
76

Effect of market anomalies on expected returns on the JSE: A cross-sector analysis

Mahlophe, Mpho Innocentia January 2015 (has links)
The efficient market hypothesis and behavioural finance have been the cause of much debate for decades, with one theory advocating market efficiency and the other opposing it. The efficient market hypothesis (EMH) assumes that investors always act rationally and stock prices adjust rapidly to new information and should reflect all available information. In contrast, behavioural finance suggests that markets are not rational and investors make irrational decisions, which may lead them to over- or under-price stocks. Researchers for years have been empirically testing these assumptions in stock markets. However, there has been no consensus on which asset-pricing models perform better in capturing the effect of market anomalies and what impact these market anomalies have on the expected returns of different stock market’s sectors. The aim of the study was to test the effect of selected market anomalies on expected return in different sectors of the Johannesburg Stock Exchange (JSE). More specifically, the study aimed to compare the performance of different asset-pricing models and their ability to account for market anomalies in different sectors of the JSE. Additionally, this study tested the applicability of the recent Fama and French five (FF5-factor) model, in estimating the expected return on the JSE. The study used a quantitative approach with secondary data over a period of 12 years starting from January 2002 to December 2014. The sample used in the study consists of monthly data obtained from McGregor BFA and the South African Reserve Bank. The study examined for the effects of size, value, January and momentum variables across six sectors of the JSE. This was accomplished by the use of various asset-pricing models such as the Capital asset pricing model (CAPM), the Fama and French three-factor model (FF3-factor), the Carhart four-factor model (C4F) and the recent five-factor model of Fama and French (FF5-factor). The study showed that whenever the asset-pricing models were not restricted, they tend to capture the market anomalies in four out of the six sectors examined. However, no market anomalies were found present in two of the six sectors analysed. In contrast, when the asset-pricing models are restricted, the asset-pricing models only seem to capture the effects of market anomalies in one of the six examined sectors. The findings in this study suggest that market anomalies are sensitive to model specifications, as restricting the models tends to capture the different market anomalies across the sectors of the JSE. The study also found that market anomalies differ across sectors and that some sectors are more efficient than others. The study also reveals that the FF5-factor model is able to account for expected returns on the JSE. In addition, the FF5-factor model tends to perform better when the model is restricted. It is also evident from the findings presented in this study, that the value anomaly loses its predictive power when profitability and investment variables are included in the model. Overall, the study illustrated that market anomalies have an effect on returns of the JSE, that the model specifications play an important role in an asset-pricing model and that the FF5-factor model is applicable on the JSE, however, it is not certain whether four or five factors apply to the South African market.
77

Effect of market anomalies on expected returns on the JSE: A cross-sector analysis

Mahlophe, Mpho Innocentia January 2015 (has links)
The efficient market hypothesis and behavioural finance have been the cause of much debate for decades, with one theory advocating market efficiency and the other opposing it. The efficient market hypothesis (EMH) assumes that investors always act rationally and stock prices adjust rapidly to new information and should reflect all available information. In contrast, behavioural finance suggests that markets are not rational and investors make irrational decisions, which may lead them to over- or under-price stocks. Researchers for years have been empirically testing these assumptions in stock markets. However, there has been no consensus on which asset-pricing models perform better in capturing the effect of market anomalies and what impact these market anomalies have on the expected returns of different stock market’s sectors. The aim of the study was to test the effect of selected market anomalies on expected return in different sectors of the Johannesburg Stock Exchange (JSE). More specifically, the study aimed to compare the performance of different asset-pricing models and their ability to account for market anomalies in different sectors of the JSE. Additionally, this study tested the applicability of the recent Fama and French five (FF5-factor) model, in estimating the expected return on the JSE. The study used a quantitative approach with secondary data over a period of 12 years starting from January 2002 to December 2014. The sample used in the study consists of monthly data obtained from McGregor BFA and the South African Reserve Bank. The study examined for the effects of size, value, January and momentum variables across six sectors of the JSE. This was accomplished by the use of various asset-pricing models such as the Capital asset pricing model (CAPM), the Fama and French three-factor model (FF3-factor), the Carhart four-factor model (C4F) and the recent five-factor model of Fama and French (FF5-factor). The study showed that whenever the asset-pricing models were not restricted, they tend to capture the market anomalies in four out of the six sectors examined. However, no market anomalies were found present in two of the six sectors analysed. In contrast, when the asset-pricing models are restricted, the asset-pricing models only seem to capture the effects of market anomalies in one of the six examined sectors. The findings in this study suggest that market anomalies are sensitive to model specifications, as restricting the models tends to capture the different market anomalies across the sectors of the JSE. The study also found that market anomalies differ across sectors and that some sectors are more efficient than others. The study also reveals that the FF5-factor model is able to account for expected returns on the JSE. In addition, the FF5-factor model tends to perform better when the model is restricted. It is also evident from the findings presented in this study, that the value anomaly loses its predictive power when profitability and investment variables are included in the model. Overall, the study illustrated that market anomalies have an effect on returns of the JSE, that the model specifications play an important role in an asset-pricing model and that the FF5-factor model is applicable on the JSE, however, it is not certain whether four or five factors apply to the South African market.
78

Energy Efficient Vehicle Policy: Lessons Learnt : An analysis of the effects of incentive policies on the demand, usage and pricing of energy efficient vehicles.

Whitehead, Jake January 2016 (has links)
Encouraging the uptake of energy efficient vehicles (EEVs) is an aspiration of critical importance in a day and age in which we are confronted with the increasingly dire consequences of human behaviour on our planet, and on the planet for generations to come. The transport sector is one of the highest contributors of anthropogenic greenhouse gas emissions, whilst pollution from this sector is responsible for a large proportion of human deaths each and every year. Given the severity of these issues, it is more important than ever for policy-makers, and researchers alike, to encourage a transition within the community towards more sustainable lifestyles. Transportation is key to this change. As a service that every human being uses, almost every day of his or her life, the transport sector presents a unique opportunity for behavioural change. Through efficient and targeted policies, consumers can be incentivised to make more sustainable transport choices and to consider the consequences of their own actions. Foremost amongst these initiatives is that of encouraging a transition towards energy efficient vehicles. This thesis has been produced in order to shed further light on issues affecting this transition. In particular for policy-makers, this document includes a series of recommendations based on prevailing findings in the current literature, in addition to the novel and significant findings of this research effort. These include the various lessons learnt from government policies that have already been implemented in regions around the globe. As a thesis by publication, this document consists of four research articles that investigate factors affecting the EEV market, specifically in terms of: consumer demand, vehicle usage and product pricing. A number of other demographic and economic factors have also been examined, including the role of economies-of-scale. / Att uppmuntra ökad användningen av energieffektiva fordon (EEVs) är en strävan av avgörande betydelse i en tid då vi konfronteras med de allt mer ödesdigra konsekvenserna av människors påverkan på vår planet, i dag och för kommande generationer. Transportsektorn är en av de sektorer som bidrar mest till utsläppen av antropogena växthusgaser. Utsläpp från transportsektorn bidrar även till ett stort antal dödsfall varje år. Med tanke på vikten av dessa frågor är det viktigare än någonsin för beslutsfattare och forskare att bidra till en samhällsövergång mot mer hållbara livsstilar. Transporter är avgörande i denna omvandling. Eftersom transporter är en tjänst som alla människor utnyttjar i stort sett varje dag, erbjuder transportsektorn en unik möjlighet till beteendeförändringar. Genom effektiva och målinriktade åtgärder kan konsumenter ges incitament att göra mer hållbara transportval och överväga konsekvenserna av sina handlingar. Främst bland dessa initiativ är en uppmuntran till en övergång mot mer energieffektiva fordon. Denna avhandling har tagits fram i syfte att belysa frågeställningar som berör denna övergång. För framför allt beslutsfattare innehåller avhandlingen en rad rekommendationer baserade på såväl rådande forskningsresultat från aktuell forskningslitteratur som nya resultat från denna forskningsinsats. Dessa inkluderar erfarenheter från redan implementerade politiska åtgärder från regioner runt om i världen. Denna sammanläggningsavhandling består av fyra forskningsartiklar som undersöker faktorer som påverkar EEV-marknaden vad gäller konsumentefterfrågan, fordonsanvändning och produktprissättning. Utöver dessa har även ett antal andra demografiska och ekonomiska faktorer, inklusive betydelsen av stordriftsfördelar, undersökts. / <p>QC 20160503</p>
79

FQPSK DEVELOPMENTS RECOMMENDED FOR CCSDS STANDARDIZATION BY NASA JPL

Martin, Warren L. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / In 1992, international space agencies became concerned that increasing frequency band congestion, together with attempts by the mobile telephone industry to obtain additional bandwidth, would result in substantially more interference incidents. The CCSDS undertook a technical study to identify and recommend more bandwidth efficient modulation schemes, which would permit more users to co-exist in a frequency band while reducing interference incidents. This paper describes the contribution of the Jet Propulsion Laboratory (JPL) to that effort.
80

PERFORMANCE STUDY OF ENHANCED FQPSK AND CONSTRAINED ENVELOPE MODULATION TECHNIQUES

Borah, Deva K., Horan, Stephen 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / This paper investigates the spectral properties and the bit error rate (BER) performance of enhanced FQPSK (EFQPSK) and constrained envelope modulation (CEM) techniques. Both the techniques are found to provide good spectral efficiencies. The EFQPSK signals are found to generate spectral lines for unbalanced data. An analytical spectral study for the spectral lines is presented. While the performance of CEM techniques has been presented in [6] for an ideal nonlinear amplifier, we present results for more realistic amplifiers with AM/AM and AM/PM effects. It is shown that such an amplifier generates spectral regrowth and a predistorter is required to reduce the adverse effects. A BER performance study with/without channel coding is also presented for the two techniques.

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