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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.
151

Adaptation strategies among farmers in the Gujrat and Jhelum districts, Pakistan

Saleemi, Sanna January 2016 (has links)
Climate change imposes major threats for farming communities in South Asia as increased temperatures and changes in precipitation impact yields. Local farmers in Pakistan are facing similar challenges and the country has already been highly affected by climate change. Further, local knowledge is increasingly being recognized as an important complement to quantitative climate data. There is a need to go beyond the quantitative results in climate change research, and ground proof these data by including local experiences. Many farmers around the world are experiencing climate change and are responding to these with various adaptation strategies. This study examines climate change in the Gujrat and Jhelum districts in the Punjab province in Pakistan, how local farmers perceive climate change and what adaptation strategies local farmers have implemented. The study also intends to examine the main constraints to adaptation by incorporating expert views to analyze issues and gaps in the system. The results show increased temperatures and decreased precipitation in the study region between 1975-2014. Farmer surveys indicate that a majority of the farmers perceive these changes and have applied different adaptation strategies as a response. These strategies mainly consist of: changing planting/sowing time and increased irrigation using groundwater. A third form of response to smaller yields and decreased income was alternative off- farm jobs, as an additional income. Expert interviews reveal contradictions of implementation of climate change adaptation policies along with contrasting responses to the farmers regarding institutional efforts to support the local farmers. These results show how lack of institutional support is hindering effective, successful and long-term adaptation for these farming communities.
152

The use of AFLP to determine if a slimes-tolerant indigenous species shows local adaptation to slimes dam soils

Angus, Caroline Jane 15 November 2006 (has links)
Student Number : 9903228W - MSc dissertation - School of Molecular and Cell Biology - Faculty of Science / Plant populations show an ability to survive and adapt under varying environmental conditions. Adaptation to heavy metal contaminated soils usually results in a decrease in genetic variation. Slimes dams consist of the pulverized rock slurry left after the extraction of gold or uranium. High toxicity levels mean that these wastes often remain uncolonised and are therefore easily eroded through wind or water. Plant populations that will be viable for long-term vegetation of slimes dams will prevent erosion, and stabilise and improve the quality of the soil. Indigenous, locally adapted species are the most likely to be successful candidates for vegetation. Indigenous, slimes-tolerant species Indigofera adenoides and Indigofera zeyheri were therefore studied. The aim was to determine if plant populations show local adaptation to the adverse substrate conditions emanating from slimes dams, by investigating genetic and morphological variation between adjacent populations growing at different distances in relation to slimes dams. The AFLP technique was used to analyse genetic variation as it produces rapid results, is inexpensive, reproducible, and capable of screening the entire genome. Lower genetic diversity was observed in those areas of the dams with higher levels of slimes-associated contamination. This difference was observed in both species, and for all measures of genetic diversity (Shannon’s information index, Nei’s gene diversity, percentage of loci polymorphic). This may be due to a founder effect following colonisation, natural selection, flowering time differences, or a combination of these factors. Reduced morphological variation was observed in those areas of the dams with higher levels of slimes-associated contamination. Significant morphological differences were observed between groups of plants from different areas, some of which appear to have the capability to assist the plants in a slimes-contaminated environment. Some degree of adaptation to slimes-contaminated soil therefore seems to have occurred, with this being more pronounced in Indigofera adenoides, although it cannot be determined whether this is purely phenotypic, or a combination of phenotypic and genetic. These species therefore seem suitable as candidates for vegetation of slimes dams, although further work must be done to fully understand the effect of slimes-associated toxicity.
153

Activity patterns of green iguana (Iguana iguana) at Hugh Taylor Birch State Park, Fort Lauderdale, Florida

Unknown Date (has links)
Activity patterns of Iguana iguana from two locations within Hugh Taylor Birch State Park, Fort Lauderdale, Florida were documented and examined. Between May 1, 2006 to April 20, 2007, I. iguana were observed on a routine basis and activities were documented as one of six major activity categories (basking, locomotion, foraging, resting, visual signaling, and other). Data was analyzed to determine differences between activity patterns of I. iguana relative to sites, seasons, and size category within the park. Iguana iguana spent more time basking at Site 1 than Site 2. Size 4 animals which consisted of dominant adult males, spent more time basking than other males and adult females. Size 4 animals also spent less time foraging than hatchlings, juveniles, and other adults. These results complement the existing research on behavior of I. iguana and may be useful in determining invasive control efforts of I. iguana in Florida. / by Stacey R. Sekscienski. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
154

Shakedown of porous materials / Adaptation plastique des matériaux poreux

Zhang, Jin 28 September 2018 (has links)
Cette thèse est consacrée à la détermination des états limites de l'adaptation des matériaux ductiles poreux sur la base du théorème de Melan et en considérant le modèle de la sphère creuse. Dans un premier temps, nous proposons le critère analytique macroscopique d'adaptation avec la matrice de von Mises sous deux charges particuliers, alterné et pulsé. Le critère analytique dépend des première et seconde invariants des contraintes macroscopiques, du signe du troisième et du coefficient de Poisson. Ensuite, ce critère est étendu aux charges cycliques répétées générales par la construction d'un champ de contraintes résiduelles d'essai plus approprié permettant simultanément des calculs analytiques et l'amélioration du modèle précédent. De plus, il est également utilisé pour les matériaux ductiles poreux avec une matrice de Drucker-Prager.L'idée repose d'abord sur la solution exacte pour le charge purement hydrostatique. Il s'avère que la ruine se produit par fatigue. Ensuite, des champs de contrainte d'essai appropriés sont construits avec des termes supplémentaires pour capter les effets de cisaillement. Le domaine de sécurité, défini par l'intersection du domaine d'adaptationet celui d'analyse limite (la ruine survenant brusquement par formation d'un mécanisme au premier cycle), est entièrement comparé avec des simulations élasto-plastique incrémentales et des calculs directs simplifiés.Enfin, nous fournissons une méthode numérique directe pour prédire le domaine de sécurité de l'adaptation des matériaux poreux soumis à des charges variant de manière indépendante en considérant le chemin critique du domaine de chargement au lieu de l'histoire entière. Le problème de l'adaptation est transformé en un problème d'optimisation de grande taille, qui peut être résolu efficacement par l'optimiseur non-linéaire IPOPT pour donner non seulement le facteur de charge limite, mais aussi le champ de contrainte résiduelle correspondant à l'état d'adaptation. / This thesis is devoted to the determination of shakedown limit states of porous ductile materials based on Melan's static theorem by considering the hollow sphere model, analytically and numerically. First of all, we determine the analytical macroscopic shakedown criterion of the considered unit cell with von Mises matrix under alternating and pulsating special loading cases. The proposed macroscopic analytical criterion depends on the first and second macroscopic stresses invariants, the sign of the third one and Poisson's ratio. Then, the procedure is extended to the general cyclically repeated loads by the construction of a more appropriate trial residual stress field allowing analytical computations and the improvement of the previous model simultaneously. Moreover, this approach is applied to porous materials with dilatant Drucker-Prager matrix.The idea relies firstly on the exact solution for the pure hydrostatic loading condition. It turns out that the collapse occurs by fatigue. Next, suitable trial stress fields are built with additional terms to capture the shear effects. The safety domain, defined by the intersection of the shakedown limit domain and the limit analysis domain corresponding to the sudden collapse by development of a mechanism at the first cycle, is fully compared with step-by-step incremental elastic-plastic simulations and simplified direct computations. At last, we provide a direct numerical method to predict the shakedown safety domain of porous materials subjected to multi-varying independent loadings by considering the critical loading path of the load domain instead of the whole history. The shakedown problem is transformed into a large-size optimization problem, which can be solved efficiently by the non-linear optimizer IPOPT to give out not only the limit load factor, but also the corresponding residual stress field for the shakedown state.
155

Subband acoustic echo cancellation

Huo, Jiaquan January 2004 (has links)
The main theme of this thesis is the control of acoustic echoes for modem voice communication systems by means of echo cancellation. Two important issues in acoustic echo cancellation, namely the efficient adaptation of the echo cancellation filter and the reliable adaptation of the echo cancellation filter in double talk environment, are investigated. The delayless subband adaptive filter architecture is studied. Efficient implementation of the analysis filter bank and the time domain filtering are derived. The transforming of the subband filter weights to a fullhand counterpart is examined. It is shown that the weight transform is a synthesis filtering procedure. Two new weight transform schemes that deliver substantial performance improvements are proposed. The open-loop optimal subband filter impulse responses are shown to be non-causal and several anti-causal laps in the subband filters are required to model this non-causality. Because of the inevitable double talk detection errors, adaptive filtering algorithms with built-in double talk robustness measures are needed for the reliable operation of the echo canceller. The basic idea of robust adaptive filtering is examined. A comparison of different existing time domain robust adaptive filtering algorithms demonstrates that excellent trade-off between the convergence and the tracking properties and the double talk robustness of the adaptive filtering algorithm can he achieved by using Huher’s method for both the update of the echo cancellation filter and the estimation of scale. A delayless closed-loop robust sub- hand adaptive filter is proposed. / By independently adapting the scale estimates and normalizing the adaptation in each subband, significant improvement in terms of the convergence and tracking speed over the time domain robust NLMS algorithm can be obtained without sacrificing the double talk robustness. Moreover, it is demonstrated that by using different thresholds in the update of the echo cancellation filter and the scales, the robust algorithms converge and track echo path variation as fast as their non-robust counter part while still maintaining a sufficiently low sensitivity to double talk detection errors. The application of two path adaptive filters to acoustic echo cancellation is examined. An analysis of the original two path adaptive filtering algorithm shows that it suffers from two kinds of performance degradation due to the divergence of the background filter during double talk, namely the slow tracking of echo path variation and the false filter coefficient copying after double talk. A robust two path adaptive filter is proposed to mitigate these problems.
156

The Molecular Bases of Training Adaptation

Coffey, Vernon Glenn, vernon.coffey@rmit.edu.au January 2006 (has links)
The molecular events that promote or inhibit specific training adaptations (i.e. skeletal muscle hypertrophy or mitochondrial biogenesis) are not completely understood. Accordingly, there is a need to better define both the acute and chronic responses to divergent exercise stimuli in order to elucidate the specific molecular mechanisms that ultimately determine skeletal muscle phenotype. Therefore, the primary aims of the studies undertaken for this thesis were to examine the acute molecular adaptation responses in skeletal muscle following resistance and endurance training. In order to determine the acute molecular events following repeated bouts of exercise, the study described in Chapter Two compared a high-frequency stacked training regimen designed to generate a summation of transient exercise-induced signalling responses with a conventional-frequency resistance training protocol. Groups (n= 6) of Sprague-Dawley rats performed either high-frequency training (four exercise bouts consisting of 3 - 10 repetitions separated by 3 h) or conventional-frequency training (three exercise bouts consisting of 4 - 10 repetitions with 48 h between sessions). Protocols were matched for total work, and repetitions were performed at 75% one-repetition maximum with 3 min recovery between sets. White quadriceps muscle was extracted 3 h after every training bout, and 24 and 48 h following the final exercise session of each protocol. AKT phosphorylation was significantly decreased 3 h following the 2nd bout of high-frequency training, an effect that persisted until 48 h after the final exercise bout (P less than 0.05), while the phosphorylation state of this kinase was unchanged with conventional training. These results suggest that high-frequency training suppressed IGF-1 mediated signalling. Furthermore, high-frequency training generated sustained and coordinated increases in TNFá and IKK phosphorylation (P less than 0.05), indicating an extended response of inflammatory signalling pathways. Conversely, and irrespective of an initial increase after the first bout of exercise, TNFá signalling ultimately returned to control Abstract values by DAY 5 of conventional-frequency training, indicative of a rapid adaptation to the exercise stimulus. Notably, despite differential AKT activation there were similar increases in p70 S6K phosphorylation with both training protocols. These results indicate high-frequency resistance training extends the transient activation of inflammatory cytokine-mediated signalling and results in a persistent suppression of AKT phosphorylation, but these events do not appear to inhibit kinase activity proximal to translation initiation. The aim of the study described in Chapter Three was to determine the effect of prior training history on selected signalling responses after an acute bout of resistance and endurance exercise. Following 24 h diet / exercise control 13 male subjects (7 strength-trained and 6 endurance-trained) performed a random order of either resistance (8 x 5 maximal leg extensions) or endurance exercise (1 h cycling at 70% peak O2 uptake). Muscle biopsies were taken from the vastus lateralis at rest, immediately and 3 h post-exercise. AMPK phosphorylation increased after cycling in strength-trained, but not endurance-trained subjects (P less than 0.05). Conversely, AMPK was elevated following resistance exercise in endurance-, but not strength-trained subjects (P less than 0.05). Thus, AMPK was elevated only when subjects undertook a bout of exercise in a mode of training to which they were unaccustomed. Surprisingly, there was no change in AKT phosphorylation following resistance exercise regardless of the training background of the subjects. In the absence of increased AKT phosphorylation, resistance exercise induced an increase in p70 S6K and ribosomal S6 protein phosphorylation in endurance-trained but not strength-trained subjects (Pless than 0.05). AKT phosphorylation was increased in endurance-trained, but not strength-trained subjects after cycling (P less than 0.05). These results show that a degree of signalling
157

Cultural Evolution and Advertising Strategies : Which future for TV commercials?

Bonesire, Thomas, Bouvy, François January 2009 (has links)
<p>This thesis deals with TV advertising strategies, namely adaptation and standardization, and with the impact of cultural homogenization on these strategies. Indeed, globalization generates the convergence of world cultures and especially of young Europeans’ cultures. This relative convergence in people’s habits, behaviour and values could allow advertisers to use more standardized advertisements without losing too much impact on the consumer. The use of standardized advertisements is interesting to create a uniform brand image, appeal to cross-border segments and, of course, make economies of scale. This thesis surveys young Europeans, represented by Swedes and Belgians, to examine their degree of cultural homogenization, i.e., if they are culturally similar enough for standardization to be effective on this group. Moreover, it compares the impact of both adapted and standardized commercials on this young European audience. This study comes to two main findings. First, the young Swedish and Belgian cultures have similarities, which standardized commercials can exploit, but also differences. This shows that we can speak about cultures’ convergence but not about a complete homogenization. Second, standardization seems to be effective - as effective as adaptation - in its appeal to young Swedes and Belgians. This shows that, given its advantages, standardization is certainly the most adequate method for targeting a young European audience. The findings for Sweden and Belgium should be valid for the whole EU. The thesis also discusses the generalization of the findings to the rest of the world and other age ranges as well as the future of commercials.</p>
158

TWO COUNTRIES - ONE MARKETING MIX? HOW TO ADOPT COMPANY’S MARKETING MIX TO FOREIGN MARKET - CASE STUDY OF VOLVO

Szwejkowska, Aneta, Puczynski, Leszek, Jezierski, Konrad January 2007 (has links)
<p>The discussion about 4P’s marketing mix covers two aspects. On the one hand, marketing mix activities are used to apply product into market and attract customers. Its activities are matched with every single market in different way. Managers are focused on country specification, customers’ demands and potential competitors. They analyse all factors, which can influence on future product’s adaptation. Enterprise’s success is measured by amount of selling as well as customer satisfaction and behaviour. On the other hand, it is not obviously that companies need to change their marketing strategies every time, when they want to expand their market to being more international. From this point of view differentiation among marketing mix activities are useful for at first gain new target group and meet their requirements. Subsequently, product can be customized. This thesis concludes theories about marketing mix components and its practical application.</p>
159

A New Original : The Adaptation of The Remains of The Day

Freiholtz, Anna January 2009 (has links)
<p>The essay investigates the film adaptation <em>The Remains of the Day</em>. The novel and film are used to give examples of ways the story of a novel can change when it is adapted for film. The theoretical framework is based on Linda Hutcheon's concept of orginality and fidelity.</p>
160

Robust Incentive Contracts

Wernerfelt, Birger 13 February 2004 (has links)
We look at a principal-agent model in which the agent has to perform an action, the difficulty of which is better known ex interim than ex ante. We compare two contracting regimes; one with commitment to an ex ante negotiated contract, and one with an ex interim negotiated contract. The ex ante contract can not be too steep, but attempts to negotiate a steeper ex interim contract may result in bargaining failure. We find that the relative efficiency of the two contracting regimes depends on the nature of the differences between tasks. In a dynamic version of the analysis, we further find that the comparison depends on the frequency with which new tasks are needed. The argument can be interpreted as an analysis of the tradeoff between weak incentives in the firm and the possibility of unsuccessful negotiations in the market

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