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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.
291

The role of tourism in natural resource management in the Okavango Delta, Botswana.

Harrison, Phillipa Anne. January 2006 (has links)
In recent years the use of tourism as a development strategy by Third World governments has increased, resulting in the intersection of international tourism and local resource utilisation patterns. The aim of this thesis is to critically assess the impact of tourism in the utilisation and management of natural resources in the Okavango Delta in Botswana. More specifically, the study appraises the current state of tourism and natural resource utilisation and management in the Okavango Delta; assesses the past and present forms of resource utilisation practised by the local inhabitants scattered throughout the Delta area; focuses on the implementation of government policy regarding resource use; highlights past and present relationships between tourism and resource utilisation; and examines the impact of tourism on the areas resources, environment and local inhabitants. Research has shown that the Okavango Delta, which is Botswana's primary tourism area, is faced with a number of social, economic and environmental challenges. These include extreme levels of poverty, especially in the rural areas; lack of infrastructure; competition over land and resources; growing regional inequality; social degradation; increased imports leading to foreign exchange leakages; changes in subsistence strategies and increased 'rural-urban' .migration; and the loss of control of the region by the local population to the global tourism system. The Okavango Delta is in the process of undergoing a change from traditional, rural, subsistence economies and livelihoods to capitalist, commercial-driven economic structures. In the Okavango Delta, as in many places around the world, people are in the process of being integrated into national level political, social and economic institutions, both within and outside of their control. The creation of employment for the local population, the sustainable use of the Delta and its resources, the development of the local agricultural industry, the continued growth of the tourism industry, and striking a balance between the conservation/preservation of the Okavango and meeting the water requirement needs of Angola, Namibia, and Botswana's growing populations are amongst the key concerns present in the area. 11 Tourism in the Okavango Delta is directly dependent upon the utilisation of the region's natural resources of wildlife, water and natural vegetation areas for the industry. As such, tourism has increasingly impacted upon the way, and degree to which, these resources are managed and utilised, hence being identified as a key factor effecting the resource sector. If the Government of Botswana is to develop a tourism industry which fosters environmental and natural resource preservation, rather than maintaining a heavy dependence on limited and fragile resources, a better understanding of the relationship between the two sectors is necessary. Enhancing the positive linkages between tourism and natural resource utilisation in the Okavango Delta region represents an important means to stimulate increased natural resource and environmental protection, and improve the distribution of tourism benefits to rural communities. amongst the key concerns present in the area. Tourism in the Okavango Delta is directly dependent upon the utilisation of the region's natural resources of wildlife, water and natural vegetation areas for the industry. As such, tourism has increasingly impacted upon the way, and degree to which, these resources are managed and utilised, hence being identified as a key factor effecting the resource sector. If the Government of Botswana is to develop a tourism industry which fosters environmental and natural resource preservation, rather than maintaining a heavy dependence on limited and fragile resources, a better understanding of the relationship between the two sectors is necessary. Enhancing the positive linkages between tourism and natural resource utilisation in the Okavango Delta region represents an important means to stimulate increased natural resource and environmental protection, and improve the distribution of tourism benefits to rural communities. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2006
292

Knowledge sharing among staff at Delta State University Library Abraka for improved service provision

Izu, Lydia Osarugue 11 1900 (has links)
Academic libraries are an integral part of higher educational institutions in Nigeria in order for them to achieve their mission of national development. Knowledge sharing has become a survival kit for academic libraries to improve service provision and remain relevant in today’s information world. This study explores the roles of knowledge sharing among staff at the Delta State University (DELSU) library, Abraka for improved service provision and also suggests strategies to enhance knowledge sharing among staff for improved service provision. The theory of organisational knowledge creation (SECI) and the Social Exchange Theory (SET) underpinned this study. The study adopted a mixed method research approach and case study research design. While questionnaires were the main data collection instruments, interviews were the supplementary instruments. The entire staff at the DELSU library, Abraka was the target population for this study. A census was taken on the entire staff of the library to collect data using the questionnaires while the heads of the different library sections were purposively sampled for the collection of data through interviews. The quantitative data collected using questionnaires was analysed with the Statistical Package for Social Science (SPSS) software and the results were presented in tables and simple descriptive statistics. The interview data was analysed and interpreted using thematic analysis and was presented in predetermined themes according to the research objectives. A total of 60 out of the 63 copies of the questionnaire administered were retrieved and interviews were conducted on all seven participants sampled. The study revealed that knowledge sharing among staff members play an important role in improving service provision in the library in terms of the provision of accurate and in time services, learning best library practices, avoidance of mistake repetition and solving problems encountered on the job. However, knowledge sharing is not formalised in the library. Therefore, effective knowledge sharing for service provision has not been achieved. The greatest barriers to knowledge sharing for improved service provision in the library are the lack of a knowledge sharing culture, information and communication technological tools and infrastructures and motivation as well as the inferiority and superiority complex among staff. The greatest motivation for the library staff to share knowledge is to improve service provision. The study suggests strategies to encourage knowledge sharing among the staff members in order to improve service provision. These strategies include an adequate reward system, as well as a continuous awareness and appraisal of knowledge sharing. / Information Science / M. Inf.
293

China : capillarity and territory : paradigms of diffuse urbanization / Chine : capillarité et territoire : paradigmes de l'urbanisation diffuse

Palmioli, Andrea 02 May 2018 (has links)
Cette recherche interroge l’existence des nouvelles formes de ruralité émergentes dans le bassin métropolitain du delta du Yangzi. En opposition à l’écart croissant entre patrimoine infrastructurel et société on réaffirme la priorité du territoire comme principe théorique et paradigme naturel. L’analyse des processus historiques d’aménagement du territoire agricole à partir des réformes foncières et des pratiques autochtones de « Guangxi » (réseaux sociaux), a révélé une restructuration des ressources stratégiques du territoire du delta avant la réorganisation des espaces ruraux bâtis : la nature du sol et le réseau de l’eau. En même temps dispositif de contrôle politique et de développement social, la modification de l’infrastructure territoriale jusqu’ à la fin du maoïsme, peut être interprétée comme un investissement sur le long terme du capital humain et environnemental. Notre hypothèse est que la diffusion des petites et moyennes entreprises dans les zones rurales représente une forme de capitalisation des matrices sociales et organisationnelles du tissu agricole plus ancien. Ces transformations ont amené à la formation de nombreux espaces hybrides et clusters des entreprises dispersées dans la campagne qui s’appuient de façon complémentaire aux réseaux environnementaux préexistants. En conséquence, ce mode de production a à son tour, remodelé la relation entre l'économie, les communautés et l'environnement naturel locaux donnant lieu à des formes du développement sans fractures, plus ductiles et résilientes où la relation entre l'espace construit et l'espace agricole n'est plus de nature opposée. Ce qui émerge est un réseau de “milieux” dont chaque élément rend compte de la conception d’un paysage, de matériaux propres, de méthodes et procédures de construction. L’organisation morphologique qui en résulte montre un modèle d'urbanisation capillaire dans ces zones conventionnellement définies « non-urbaines ». Interroger ces formes émergentes de ruralité veut dire réviser la façon de conceptualiser la notion du « territoire métropolitain », et notamment de ce que on définis l’ « urbain ». On fait valoir, finalement, pour un besoin urgent de reconsidérer la séquence programmatique qui sous-tendent la morphologie spatiale de régions mégalopolitaines, par la prise en compte des rapports de continuité entre « milieux » et « communauté » et par le biais d'un examen des interactions entre ces réalités souvent, disjoints / The territorial scale and the form of the territory are fundamental basis to understand metropolitan processes and the changes occurred in its spatial, economic and social structure. The centrality of landforms and of their dynamics inspires more situated approaches, in which the agency of natural elements is integrated. This research investigates the existence of new forms of emerging rurality in the metropolitan basin of the Yangtze Delta. In opposition to the growing gap between infrastructural heritage and society, the priority of the territory is reaffirmed as a theoretical tool and environmental paradigm. The research hypothesis is that the spread of small and medium-sized enterprises in rural areas represents a form of capitalization of the spatial reorganization occurred in the Commune's period. The preliminary factor which originated the process of rural industrialization is based on the restructuring of two strategic territorial resources: the soil structure and the water network. These transformations have led to the formation of numerous hybrid spaces and clusters of small and micro enterprises dispersed over the countryside. As a result, this mode of production has, in turn, reshaped the relationship between the local economy, communities and natural environment giving rise to forms of urban development without fractures, where the relationship between the built space and the agricultural area is no longer of an opposite nature. What emerges is a network of "milieu” where the resulting socio-spatial organization shows a pattern of capillary urbanization in these conventionally defined "non-urban" areas. The notion of urban is changing and ecological rationality can offer fundamental opportunities to analyse, intersect and integrate the various territorial layers
294

Land use change analysis of the urban fringe in the Zhujiang Delta by remote sensing techniques.

January 1994 (has links)
by Chan, Cheung-Wai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 184-189). / ACKNOWLEDGMENTS --- p.ii / LIST OF ILLUSTRATIONS --- p.iii / LIST OF TABLES --- p.iv / Chapter Chapter One --- Introduction --- p.1 / Chapter 1.1 --- Introduction / Chapter 1.2 --- Background / Chapter 1.3 --- Objectives of this study / Chapter 1.4 --- The Structure of the thesis / Chapter Chapter Two --- Literature Review --- p.9 / Chapter 2.1 --- Introduction / Chapter 2.2 --- Rural-urban fringe / Chapter 2.3 --- Characteristics of land use changes in the fringes / Chapter 2.4 --- Factors affecting the mechanism of land use changes in the urban fringe / Chapter 2.5 --- Parties involved in land use change decision / Chapter 2.6 --- Land use in the urban fringe of Zhujiang Delta / Chapter 2.6.1 --- Cities' in China / Chapter 2.6.2 --- Urban fringes in China ---the case of Zhujiang Delta / Chapter 2.6.3 --- Land use pattern in the Zhujiang Delta / Chapter Chapter Three --- Methodology --- p.29 / Chapter 3.1 --- Introduction --- Change detection techniques of land use changes / Chapter 3.1.1 --- A concept of change detection / Chapter 3.1.2 --- Change detection techniques / Chapter 3.2 --- Method employed to detect land use change in Zhujiang Delta / Chapter 3.3 --- Procedures / Chapter 3.3.1 --- Data description / Chapter 3.3.2 --- Preprocessing / Chapter a. --- Atmospheric correction / Chapter b. --- Image Registration / Chapter i. --- Spatial interpolation / Chapter ii. --- Intensity interpolation / Chapter 3.3.3 --- Image differencing / Chapter 3.3.4 --- Post-classification comparison / Chapter a. --- Land Use / Land Cover classification scheme / Chapter b. --- Definitions and image characteristics of land / Land cover classes / Chapter c. --- Supervised classification / Chapter d. --- Training sites / Chapter e. --- Maximum likelihood classifier / Chapter f. --- Accuracy assessment / Chapter g. --- post-classification comparison / Chapter Chapter Four --- Study Area --- p.64 / Chapter 4.1 --- Physical and agricultural landscape of Zhujiang Delta ---a general description / Chapter 4.1.1 --- Physical landscape / Chapter 4.1.2 --- Urban develoment / Chapter 4.1.3 --- Agricultural landscape / Chapter 4.2 --- Shunde / Chapter 4.2.1 --- Agricultural land use / Chapter 4.2.2 --- The image of Shunde / Chapter 4.3 --- Dongguan / Chapter 4.3.1 --- Agricultural land use / Chapter 4.3.2 --- The image of Dongguan / Chapter 4.4 --- Guangzhou / Chapter 4.4.1 --- Agricultural land use / Chapter 4.4.2 --- The image of Guangzhou / Chapter 4.5 --- Land use changes expected within the study area / Chapter Chapter Five --- Results and discussions --- p.83 / Chapter 5.1 --- Image differencing / Chapter 5.2 --- Results of classifications / Chapter 5.2.1 --- Shunde / Chapter 5.2.2 --- Dongguan / Chapter 5.2.3 --- Guangzhou / Chapter 5.3 --- Post-classification comparison change detection / Chapter Chapter Six --- Land use chancre analysis of the urban fringesin Zhujiang Delta --- p.107 / Chapter 6.1 --- Framework for discussion / Chapter 6 .2 --- Land use / land cover changes in Shunde / Chapter 6.2.1 --- Rural-to-urban changes / Chapter 6.2.2 --- Rural-to-rural changes / Chapter 6. 3 --- Land use / land cover changes in Dongguan / Chapter 6.3.1 --- Rural-to-urban changes / Chapter 6.3.2 --- Rural-to-rural changes / Chapter 6.4 --- Land use / land cover change in Guangzhou / Chapter 6.4.1 --- Rural-to-urban changes / Chapter 6.4.2 --- Rural-to-rural changes / Chapter 6 .5 --- Comparson of land use changes of the study area / Chapter 6.5.1 --- Land-use change comaprison / Chapter 6.5.2 --- Rural-to-urban changes / Chapter 6.5.3 --- Rural-to-rural changes / Chapter a. --- Origins of wet cropland and market gardening / Chapter b. --- Origins of woodland / Chapter c. --- Origins of fish ponds / Chapter 6.5.4 --- Conclusions / Chapter Chapter Seven --- Conclusion --- p.175 / Chapter 7.1 --- Land use change in the urban fringes in the Zhujiang Delta ---a comparison / Chapter 7.2 --- the applicability of western theories on land use change to the Zhujiang Delta / Chapter 7.3 --- Remote sensing method as an application for land use change monitoring in China
295

RF Sampling by Low Pass ΣΔ Converter for Flexible Receiver Front End

Qazi, Fahad January 2009 (has links)
<p>In today’s world the multi-standard wireless receivers are gaining more and more popularity. End-users want to access voice, data and streaming media from a single wireless terminal. An ideal approach for multi-standard receiver front-end is to digitize a wide band RF signal available from the antenna. All radio functions such as downconversion, demodulation and channel selection can be then performed in the digital domain. Analog to Digital Converter in such a case should guarantee very high linearity, speed and bandwidth specifications while consuming a lot of power. Unfortunately an ADC with such stringent requirements cannot be realized in today’s CMOS technology. In a typical receiver a mixer is used to downconvert the RF signal to baseband (or IF) before digitization is performed. A passive mixer is often used in this case to mitigate the effect of the low frequency flicker noise. Specially it can be a sampling mixer which also serves as a S/H circuit usually required for A/D conversion. In this thesis a lowpass sigma-delta converter with RF sampling is presented. The ΣΔ modulator is SC passive circuit plus comparator, so an operational amplifier usually needed to realize the integrator is avoided. To reduce the complexity, the sampling mixer in front of the modulator is merged with the passive loop filter. As a result the sampling mixer is closed in the modulator loop, so the overall linearity of the frontend is improved to some extent. Downconversion is combined with digitization that reduces the circuit complexity as well.The challenges while digitizing high frequency RF signal are discussed in details. Switches required to realize the loop filter are very critical and tend to be nonlinear. Parasitic effects associated with MOS transistors strongly show up at GHz frequencies. Optimized transistor sizes are obtained through simulation while addressing the speed and linearity trade-off. Another major challenge is the kT/C noise that is the real bottleneck in high frequency SC circuit design. A thermal noise model for ΣΔ-modulator with second-order loop filter is presented and it is shown that a passive ΣΔ-modulator is  in fact thermal noise limited rather than quantization noise limited. It is because the capacitor values are limited by the very high sampling frequency used in this case.The downconverting lowpass ΣΔ modulator with second order SC passive loop filter and 1-bit quantizer is simulated at transistor level in 90nm CMOS process. This modulator can operate at very high sampling frequency upto 4GHz and can sample RF signal with carrier of upto 4GHz as well. The designed ΣΔ modulator is flexible and supports sub-sampling by 2 to 8 (fs = 500MHz, ... 2GHz). Besides, the presented design is very power efficient as it does not use OpAmps – which consume most of the power in the typical ΣΔ modulators. From schematic simulation on average, signal-to-noise and distortion ratio (SNDR) of 52 dB is obtained (ENOB = 8.3). SNDR results does not vary much for three different cases of baseband digitalization, RF sampling and RF sub-sampling. This SNDR value seems to be a good number for a passive sigma-delta modulator. The detailed simulation results for the three cases discussed in the thesis work shown that, the modulator performs equally well for a wide range of sampling and RF signal frequencies.</p>
296

RF Sampling by Low Pass ΣΔ Converter for Flexible Receiver Front End

Qazi, Fahad January 2009 (has links)
In today’s world the multi-standard wireless receivers are gaining more and more popularity. End-users want to access voice, data and streaming media from a single wireless terminal. An ideal approach for multi-standard receiver front-end is to digitize a wide band RF signal available from the antenna. All radio functions such as downconversion, demodulation and channel selection can be then performed in the digital domain. Analog to Digital Converter in such a case should guarantee very high linearity, speed and bandwidth specifications while consuming a lot of power. Unfortunately an ADC with such stringent requirements cannot be realized in today’s CMOS technology. In a typical receiver a mixer is used to downconvert the RF signal to baseband (or IF) before digitization is performed. A passive mixer is often used in this case to mitigate the effect of the low frequency flicker noise. Specially it can be a sampling mixer which also serves as a S/H circuit usually required for A/D conversion. In this thesis a lowpass sigma-delta converter with RF sampling is presented. The ΣΔ modulator is SC passive circuit plus comparator, so an operational amplifier usually needed to realize the integrator is avoided. To reduce the complexity, the sampling mixer in front of the modulator is merged with the passive loop filter. As a result the sampling mixer is closed in the modulator loop, so the overall linearity of the frontend is improved to some extent. Downconversion is combined with digitization that reduces the circuit complexity as well.The challenges while digitizing high frequency RF signal are discussed in details. Switches required to realize the loop filter are very critical and tend to be nonlinear. Parasitic effects associated with MOS transistors strongly show up at GHz frequencies. Optimized transistor sizes are obtained through simulation while addressing the speed and linearity trade-off. Another major challenge is the kT/C noise that is the real bottleneck in high frequency SC circuit design. A thermal noise model for ΣΔ-modulator with second-order loop filter is presented and it is shown that a passive ΣΔ-modulator is  in fact thermal noise limited rather than quantization noise limited. It is because the capacitor values are limited by the very high sampling frequency used in this case.The downconverting lowpass ΣΔ modulator with second order SC passive loop filter and 1-bit quantizer is simulated at transistor level in 90nm CMOS process. This modulator can operate at very high sampling frequency upto 4GHz and can sample RF signal with carrier of upto 4GHz as well. The designed ΣΔ modulator is flexible and supports sub-sampling by 2 to 8 (fs = 500MHz, ... 2GHz). Besides, the presented design is very power efficient as it does not use OpAmps – which consume most of the power in the typical ΣΔ modulators. From schematic simulation on average, signal-to-noise and distortion ratio (SNDR) of 52 dB is obtained (ENOB = 8.3). SNDR results does not vary much for three different cases of baseband digitalization, RF sampling and RF sub-sampling. This SNDR value seems to be a good number for a passive sigma-delta modulator. The detailed simulation results for the three cases discussed in the thesis work shown that, the modulator performs equally well for a wide range of sampling and RF signal frequencies.
297

Women's protests in Egi and Warri, Nigeria, 1998 -2009 : the politics of oil, nonviolent resistance, and gender in the Niger Delta

Brodrick-Okereke, Mabel January 2013 (has links)
No description available.
298

Teamprocessen i en kreativ grupp :  – En rekonstruktion av ”6δ-modellen” i arbetslivet / The team process of a creative group : - a reconstruction of the “6δ-model” in working life.

Holmström, Elsah, Tehyrell, Jasmine January 2016 (has links)
Titel: Teamprocessen i en kreativ grupp – en rekonstruktion av “6δ-modellen” i arbetslivet. Kurs: Examensprojekt i innovationsteknik, INO325. Författare: Elsah Holmström, Jasmine Tehyrell. Syfte: Syftet är att studera och tolka 6δ-modellen (Backström &amp; Söderberg, 2015) för att sedan utföra vidare forskning och rekonstruera modellen på t e a m i arbetslivet. Syftet är också att bidra med ytterligare empiri gentemot Backström &amp; Söderberg samt att undersöka hur modellen accepteras i arbetslivet då det är där den skulle kunna användas i ett senare skede. Frågeställning: Vilka faktorer bör uppmärksammas vid en eventuell användning av 6δ-modellen på team i arbetslivet? M e t o d : Kvalitativ metod, aktionsforskning, 6δ-modellen, abduktiv ansats, hermeneutiskt förhållningssätt, experiment, diskussion och analys. Teoretiska perspektiv: Kreativitet, innovation, gruppers innovationsförmåga, gruppkreativitet, 6δ-modellen, HID-modellen, arbetsgrupper, samarbete, homogenitet, The compensatory control theory. Slutsats: Vid en rekonstruktion av 6δ-modellen på team verksamma i arbetslivet kan faktorer som tid, engagemang och teamkultur definieras. Utgången av experimenten skiljde sig åt beroende på hur teamet tog till sig 6δ-modellen. Vidare har modellen potential att fylla en långsiktig funktion på arbetsmarknaden. / Title: The team process of a creative group - a reconstruction of the “6δ-model” in working life. Course: Bachelor thesis in innovation, INO325. Authors: Elsah Holmström, Jasmine Tehyrell. P u r p o s e : The purpose is to study and interpret the 6δ-model (Backstrom &amp; Söderberg, 2015) and then carry out further research and reconstruct the model on teams active in working life. It also aims to contribute additional empirical evidence towards Backstrom &amp; Söderberg and to explore how the model is accepted in the workplace where it aims to be tested at a later stage. Question: Which are the crucial factors that should be considered when using the 6δ-model on teams in working life? Methodology: Qualitative method, Action research, 6δ-model, abductive approach, hermeneutic approach, experiment, discussion and analysis. Theoretical perspectives: Creativity, innovation, groups' ability to innovate, group creativity, 6δ-model, HID-Model, workgroups, collaboration, homogeneity, The compensatory control theory. Conclusion: At a reconstruction of the 6δ-model on teams active in working life, factors like time, commitment and team culture is defined. The outcome of the experiments differed because of how the team took to the 6δ-model. The model also has the potential to fill a long-term function of the labor market.
299

Techniques for High-Speed Digital Delta-Sigma Modulators

Ching, Hsu January 2016 (has links)
In this theses techniques for high-speed digital delta-sigma modulator(DDSM) structures are considered. Four techniques are applied andevaluated: unfolding, increasing the number of delay elements in theinner loop, pipelining/retiming, and optimizations provided by thesynthesis tool. Of interest is to see the speed-area-power trade-offs.For implementation, three different modulators meeting the samerequirements are implemented. Each modulator has a 16-bit input andresults in a 3-bit output. The baseline case is a second-ordermodulator, which has one delay element in its inner loop. Throughoptimization, two new structures are found: to provide two delayelements in the inner loop, a fourth-order modulator is required,while to provide three delay elements, a thirteenth-order modulator isobtained.The results show that in general it is better to unfold the modulatorthan to obtain the speed-up through optimizing the arithmeticoperators with the synthesis tool. Using correct pipelining/retimingis also crucial. Finally, for very high-speed implementation, usingthe structures with more delay elements is required. Also, in manycases these are more area and power efficient compared to usingoptimized arithmetic operators, despite their higher computationalcomplexity.
300

CVSD MODULATOR USING VHDL

Hicks, William T., Yantorno, Robert E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / IRIG-106 Chapter 5 describes a method for encoding voice using a simple circuit to reduce the overall bit rate and still achieve good quality voice. This well described Continuously Variable Slope Delta Modulation (CVSD) circuit can be obtained using analog parts. A more stable implementation of CVSD can be obtained by designing an anti-aliasing input filter, an A/D converter, and logic. This paper describes one implementation of the CVSD using a standard A/D converter and logic.

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