International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In our prior work [1] we proposed that network-centric data telemetry systems offer substantial improvements over traditional serial data telemetry systems. This paper is a follow up to that work and is also a companion to our experimentation paper [2]. In network-centric telemetry systems, there can be many infrastructure sites that form the network’s ad hoc communications paths, and there can be many fast-moving nodes, e.g., munitions, which enter the network, generate telemetry data, and exit the network. As the geographic size of such data telemetry networks grows, constraints on link margin will typically preclude a one-to-one matching of ground-based infrastructure sites to airborne, fast-moving nodes. That is, the fast-moving nodes will traverse distances that will require the mobile node to change which specific ground node it communicates with to transfer telemetry data. This paper describes an analytic model for the generic process of a fast moving node entering a wireless network and the associated handoffs of that node among ground stations as the fast mover traverses the spatial region covered by the wireless network. Our analysis and associated worst-case example demonstrate that wireless networking technology can handle the stress of rapidly managing connectivity to high-speed nodes for effective telemetry data extraction.

This study aimed to determine the applicability of western migration models to the movement patterns of foreign migrant traders at the Hartebeespoort Dam. After reflecting on theoretical dimensions of migration and the informal sector, an overview was provided of the historical development of migration patterns to and within South Africa. The complex nature of migration phenomena ensures the application of qualitative and quantitative research methodologies. A snowball sampling technique was used to select 30 respondents for the purpose of the questionnaire survey. Information obtained from this survey was supplemented by five in-depth interviews. Descriptive statistical techniques were used to analyse the information obtained from the survey. The study concluded that western migration models do not offer adequate explanation for the migration patterns observed among foreign migrant traders at the Hartebeespoort Dam. The study also established the merit of the combined use of qualitative and quantitative research methodologies in migration studies. / Geography / M.A. (Geography)

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Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The expansion of the global fuels industry has caused an increase in the quantity of hydrocarbons produced as a by-product of refinery gas-to-liquid processes. Conversion of hydrocarbons to higher value products is possible using bioprocesses, which are sustainable and environmentally benign. Due to the deficiency of oxygen in the alkane molecule, the supply of sufficient oxygen through aeration is a major obstacle for the optimization of hydrocarbon bioprocesses. While the oxygen solubility is increased in the presence of hydrocarbons, under certain process conditions, the enhanced solubility is outweighed by an increase in viscosity, causing a depression in overall volumetric oxygen transfer coefficient (KLa). The rate at which oxygen is transferred is defined in terms of a concentration driving force (oxygen solubility) and the overall volumetric oxygen transfer coefficient (KLa). The KLa term comprises an oxygen transfer coefficient (KL) and the gas-liquid interfacial area (a), which are dependent on the uid properties and system hydrodynamics. This behaviour is not well understood for hydrocarbon bioprocesses and in a bubble column reactor (BCR). To provide an understanding of oxygen transfer behaviour, a model hydrocarbon bioprocess was developed using a BCR with a porous sparger. To evaluate the interfacial area, the Sauter mean bubble diameter (D32) was measured using an image analysis algorithm and gas holdup (ϵG) was measured by the change in liquid height in the column. Together the D32 and ϵG were used in the calculation of interfacial area in the column. The KLa was evaluated with incorporation of the probe response lag, allowing more accurate representation of the KLa behaviour. The probe response lag was measured at all experimental conditions to ensure accuracy and reliability of data. The model hydrocarbon bioprocess employed C14-20 alkane-aqueous dispersions (2.5 - 20 vol% hydrocarbon) with suspended solids (0.5 - 6 g/l) at discrete super ficial gas velocity (uG) (1 - 3 cm/s). For systems with inert solids (corn our, dp = 13.36 m), the interfacial area and KLa were measured and the behaviour of KLa was described by separation of the in uences of interfacial area and oxygen transfer coefficient (KL). To further the understanding of oxygen transfer behaviour, non-viable yeast cells (dp = 5.059 m) were used as the dispersed solid phase and interfacial area behaviour was determined. This interfacial area behaviour was compared with the behaviour of systems with inert solids to understand the differences with change in solids type. In systems using inert solids, a linear relationship was found between G and uG. An empirical correlation fo rthe prediction of this behaviour showed an accuracy of 83.34% across the experimental range. The interfacial area showed a similar relationship with uG and the empirical correlation provided an accuracy of 78.8% for prediction across the experimental range. In inert solids dispersions, the KLa increased with uG as the result of an increase in interfacial area as well as increases in KL. An increase in solids loading indicated an initial increase in KLa, due to the in uence of liquid-film penetration on KL, followed by a decrease in KL at solids loading greater than 2.5 g/l, due to diffusion blocking effects. In systems with yeast dispersions, the presence of surfactant molecules in the media inhibited coalescence up to a yeast loading of about 3.5 g/l, and resulted in a decrease in D32. Above this yeast loading, the fine yeast particles increased the apparent viscosity of the dispersion sufficiently to overcome the in uence of surfactant and increase the D32. The behaviour of G in yeast dispersions was similar to that found with inert solids and demonstrated a linear increase with uG. However, in yeast dispersions, the interaction between alkane concentration and yeast loading caused a slight increase in dispersion viscosity and therefore G. An empirical correlation to predict G behaviour with increased uG was developed with an accuracy of 72.55% for the experimental range considered. Comparison of yeast and inert solids dispersions indicated a 37.5% lower G in yeast dispersions compared to inert solids as a result of the apparent viscosity introduced by finer solid particles. This G and D32 data resulted in a linear increase in interfacial area with uG with no significant in uence of alkane concentration and yeast loading. This interfacial area was on average 6.7% lower than interfacial area found in inert solid dispersions as a likely consequence of the apparent viscosity with finer particles. This study provides a fundamental understanding of the parameters which underpin oxygen transfer in a model hydrocarbon bioprocess BCR under discrete hydrodynamic conditions. This fundamental understanding provides a basis for further investigation of hydrocarbon bioprocesses and the prediction of KLa behaviour in these systems. / AFRIKAANSE OPSOMMING: Die uitbreiding van die internasionale brandstofbedryf het 'n toename veroorsaak in die hoeveelheid koolwaterstowwe geproduseer as 'n deur-produk van raffinadery gas-tot-vloeistof prosesse. Omskakeling van koolwaterstowwe na hoër waarde produkte is moontlik met behulp van bioprosesse, wat volhoubaar en omgewingsvriendelik is. As gevolg van die tekort aan suurstof in die alkaan molekule, is die verskaffing van voldoende suurstof deur deurlugting 'n groot uitdaging vir die optimalisering van koolwaterstof bioprosesse. Terwyl die suurstof oplosbaarheid verhoog in die teenwoordigheid van koolwaterstowwe, onder sekere proses voorwaardes is die verhoogde oplosbaarheid oortref deur 'n toename in viskositeit, wat 'n depressive veroorsaak in die algehele volumetriese suurstofoordragkoëffisiënt (KLa). Die suurstof oordrag tempo word gedefinieer in terme van 'n konsentrasie dryfkrag (suurstof oplosbaarheid) en KLa. Die KLa term behels 'n suurstofoordragkoëffisiënt (KL) en die gas-vloeistof oppervlakarea (a), wat afhanklik is van die vloeistof eienskappe en stelsel hidrodinamika. Hierdie gedrag is nie goed verstaan vir koolwaterstof bioprosesse nie, asook in kolom reaktors (BCR). Om 'n begrip van suurstof oordrag gedrag te voorsien, is 'n model koolwaterstof bioproses ontwikkel met 'n BCR met 'n poreuse besproeier. Om die oppervlakarea te evalueer, is die gemiddelde Sauter deursnit (D32) gemeet deur 'n foto-analise algoritme en gas vasvanging ( G) is gemeet deur die verandering in vloeibare hoogte in die kolom. Saam is die D32 en G gebruik in die berekening van die oppervlakarea in die kolom. Die KLa is geëvalueer met insluiting van die meter se reaksie sloering, om n meer akkurate voorstelling van die KLa gedrag te bereken. Die meter reaksie sloering was gemeet op alle eksperimentele toestande om die akkuraatheid en betroubaarheid van data te verseker. Die model koolwaterstof bioproses gebruik n-C14-20 alkaan-water dispersies (2.5 - 20 vol% koolwaterstof) solide partikels (0.5 - 6 g/l) op diskrete oppervlakkige gas snelhede (1 - 3 cm/s). Vir stelsels met inerte solides (koring meel, dp = 13.36 m), is die oppervlakarea en KLa gemeet en die gedrag van KLa beskryf deur skeiding van die invloede van oppervlakarea en KL. Om die begrip van suurstof oordrag se gedrag te bevorder, is nie-lewensvatbare gisselle (dp = 5.059 m) gebruik as die verspreide solide fase en oppervlakarea is bepaal. Hierdie oppervlakarea gedrag is vergelyk met die van stelsels met inerte solides om die verskille met verandering in solide tipes te verstaan. In stelsels met inerte solides, is 'n line^ere verwantskap gevind tussen G en uG. 'n Empiriese korrelasie vir die voorspelling van hierdie gedrag is opgestel met 'n akkuraatheid van 83.34% in die eksperimentele reeks. Die oppervlakarea het 'n soortgelyke verhouding met uG en die empiriese korrelasie verskaf 'n akkuraatheid van 78,8% vir die voorspelling van oppervlakarea oor die eksperimentele reeks. In inerte solide dispersies, het die KLa toegeneem met uG as die gevolg van 'n toename in grens oppervlak asook stygings in KL. 'n Toename in solides belading het n aanvanklike styging in KLa aangedui, as gevolg van die invloed van die vloeistof-film penetrasie op KL, gevolg deur 'n afname in KL op vastestowwe ladings groter as 2.5 g/l, te danke aan diffusie blokkeer effekte. In stelsels met gis dispersies, het die teenwoordigheid van benattings molekules in die media samesmelting geïnhibeer tot 'n gis lading van ongeveer 3.5 g/l, en het gelei tot 'n afname in D32. Bo hierdie gis lading, het die fyn gis partikels die skynbare viskositeit van die verspreiding verhoog genoegsaam om die invloed van benattings molekules te oorkom en die D32 te verhoog. Die gedrag van G in gis dispersies was soortgelyk aan die van inerte solides en dui op 'n lineêre toename met uG. Maar in gis dispersies, het die interaksie tussen alkaan konsentrasie en gis lading 'n effense toename veroorsaak in die verstrooiing viskositeit en dus in G. 'n Empiriese korrelasie is ontwikkel om G gedrag te voorspel en het 'n akkuraatheid van 72,55% vir die eksperimentele verskeidenheid beskou. Vergelyking van gis en inerte patrikel dispersies wys 'n 37.5% laer G in gis dispersies in vergelyking met inerte vaste stowwe as 'n gevolg van die skynbare viskositeit bekendgestel deur fyner vastestowwe partikels. Hierdie G en D32 data het gelei tot 'n linere toename in grens oppervlak met uG met geen beduidende invloed van alkaan konsentrasie en gis lading nie. Die oppervlakarea was gemiddeld 6.7% laer as oppervlakarea gevind in inerte partikel dispersies as 'n waarskynlike gevolg van die skynbare viskositeit met fyner partikels. Hierdie studie bied 'n fundamentele begrip van die veranderlikes wat die suurstof oordrag definieer in 'n model koolwaterstof bioproses BCR onder diskrete hidrodinamiese voorwaardes. Hierdie fundamentele begrip bied n basis vir verdere ondersoek van koolwaterstof bioprosesse en en die voorspelling van KLa gedrag in hierdie stelsels.

<p> The purpose of the study was to determine whether family and peer risk and protective factors predicted alcohol, marijuana and cigarette use as well as alcohol-related problems among 6^th, 8^th, and 10^th grade students. This study also determined whether age moderated the relation between family and peer influences and substance use outcomes. Results demonstrated that peer alcohol use, peer positive alcohol use attitudes, and family history of drug and alcohol problems were associated with higher alcohol, marijuana, and cigarette use, as well as alcohol-related problems. Conversely, parental monitoring and peer negative alcohol use attitudes were associated with lower alcohol, marijuana, and cigarette use, as well as alcohol dependence. Moderation analyses demonstrated that among older adolescents&rsquo; social risk and protective factors were associated with higher or lower substance use, respectively. However, younger adolescents&rsquo; reported lower substance use, regardless of the level of the social influence. Implications regarding prevention programs are discussed.</p>

This thesis is conducted on the premise that the existing legal, policy and governance frameworks are insufficient to protect biodiversity from the alarming loss it is facing now. It argues that these frameworks are crafted to conform to the dominant paradigm of anthropocentrism; a paradigm which believes that humans are the pinnacle of creation and everything on Earth, including the Earth itself destined to satisfy only the interests of humanity without having their own purpose. By showing how anthropocentric worldview conceived, developed and spread, and how this worldview managed to influence societal collective consciousness to govern the relationship established between humans and the nonhuman nature, the thesis argues that loss of biodiversity not a problem in itself. Rather it is a symptom of the underlying problem rooted in human thinking, guided by anthropocentric worldview. Anthropocentrism has become a powerful paradigm that succeeded in permeating into dominant religions, knowledge base and legal systems of countries of the world, including Ethiopia. The thesis contends that law, as mirror of dominant paradigms and perceptions, reflects the values of these paradigms, at international as well as national levels putting protection of biodiversity within the interpretations of these paradigms. It argues that the human treatment of the natural environment is on a scale of violence which puts the survival of humans and that of the environment at a precarious condition. Based on evidence from the review of evolutionary science and the Holy Scriptures, the thesis argues that humans are deeply connected to and dependent on the Earth systems and are responsible to maintain these systems which are functioning in a holistic manner to support all life on Earth. Promoting the proposition of Thomas Berry that the Earth is a community of subjects not a collection of objects, it contends that biodiversity has intrinsic value in addition to instrumental value, deserving ethical extension. Drawing on these concepts, the thesis suggests, by adopting a reformist approach, a shift from the reductionist notion of anthropocentrism to ecocentrism via the new philosophy called Earth jurisprudence. Earth jurisprudence is believed to correct and heal the conflicting relationship that humans established with the nonhuman nature, with the view to reconciling the present legal, policy and governance systems which have been dominated by anthropocentric perspectives. Through the vehicle of Earth jurisprudence, it is hoped that humans assume a stewardship responsibility for the mutual benefits of humans and nonhuman nature. The thesis finally deals with a case study conducted in Sheka zone in the Southwest Ethiopia. The case study is done with the purpose of exploring the TEG systems of indigenous/local communities which are believed to conform to the tenets of the Earth jurisprudence, the philosophy of law which is chosen by this work to guide the protection of biodiversity. The case study came out with findings that the Sheka TEG systems are good examples of customary practices that provide better protection for biodiversity. Exemplary lessons can be drawn from the Sheka TEG systems to amend the dominant legal, policy and governance regimes.

Ethiopia has experimented with land law reforms linked to agriculture-led national development strategies that Emperor Haile Sellassie I, Derg, and EPRDF introduced since Emperor Menelik II enacted modern Ethiopia’s first reform intended for development in 1908. Nonetheless, the country’s smallholder productivity averaged 1.0 ton/hectare and its poverty ranked 174th in the UNDP Human Development Index in 2011. This thesis examines whether and how land law reform can be used to help raise smallholder productivity and tackle poverty in Ethiopia notwithstanding the challenges of legal pluralism. By drawing upon evidence from law and development research and experience and analysing it in the Ethiopian context, the thesis argues that reform can help raise smallholder productivity, but only by recognising legal pluralism and changing the land tenure system’s formal state or non-formal customary land policies, laws, and institutions which constrain the provision and implementation of productivity-raising smallholder land rights that enhance tenure security, facilitate the transfer of rights over land, and authorise the collateralisation of land rights; and tackle poverty by thereby increasing food supplies, raising incomes, and improving health, education, and other necessities for the country’s predominantly rural population. Specifically, the thesis explores the possibility of using reform to adopt a hybrid state-private-customary land policy that combines the advantages of state land ownership policy that the government enforces, private ownership that critics favour, and non-formal arrangements that society uses. It then highlights how within the framework of this hybrid policy reform may help issue land laws boosting the provision of land rights that enhance tenure security by specifying definition of state, private, and communal landholdings, certification of lifelong usufructuary landholding, stricter eviction and confiscation procedures, and clearer expropriation and compensation mechanisms; that facilitate transfer by easing lease, donation, and succession restrictions; and that authorise collateralisation conditionally. Finally, it demonstrates how reform may help establish land institutions that improve implementation by incorporating non-formal arrangements, establishing a federal executive institution, clarifying the mandates of regional institutions, and assigning the judiciary greater dispute resolution role.

The thesis examines the nature and mechanisms of land alienation in the context of Ethiopia's history of land relations and the role of national and global actors. In consideration of these themes, the study has adopted a contextual analysis of law and policy. Data from fieldwork has informed the core themes. It has also involved a combination of doctrinal legal research and documentary policy research augmented by quantitative data. The research considers issues of land alienation in the situation where the main relevant perspectives argue for the abolition of the people's ownership of land approach embodied in the country's 1995 Constitution and its replacement by private ownership of land (privatization perspective) or for its modification to allow alienation of land use rights (revisionist perspective) or for its change into village ownership of land with a possibility of market transfer of land use rights (associative ownership perspective). In addition to their promotion of one or another form of land alienation, the above three perspectives focus on consideration of ways to break the bureaucratic power of the State over land. This study contends that a focus on these issues has prevented the perspectives from fully identifying and thus explaining features of the ongoing land alienation in Ethiopia including the position of international institutions. This thesis therefore claims that there is an underlying shift towards marketable property in land in favor of actors who are assumed to be 'better land improvers. This is happening in a dual context of significant land poverty and economic growth.' Land alienation is being manifested in rural land expropriation laws, administrative and judicial endorsement of kontract, absence of recognition of communal lands and transfer by the State of the communal rural lands to large-scale farmers through the deployment of discourses such as 'empty land' and the 'tragedy of the commons.' This gravitation clashes with the people's ownership of land approach that provides for agricultural land for peasants and pastoralists, security of their landholdings and a ban on land alienation. The tilt has resulted in another tension between federal and regional governments where the Centre claims that efficiency demands that it handle land transfers to developers whereas the regions assert their constitutional power over land. Similarly, global institutions are involved in a contradiction because they prescribe land rights to the poor as a strategy to reduce poverty in Ethiopia and at the same time they encourage large-scale land grants in accordance with `principles of responsible agricultural investment.' The thesis proposes an affirmation of the constitutional principles concerning land with a proper form of constitutionality.

The thesis is about a contextual and prospective analysis of the Ethiopian variant of plea bargaining focusing on the major components of legal culture, legal structure and principles of criminal law and procedure. To this end, it makes use of a thorough analysis of policy and reform documents, laws, as well as comparative literature, interviews and questionnaires. The thesis argues that the Ethiopian variant of plea bargaining is less desirable and feasible. It hardly fits into the Ethiopian legal system for it is constrained by inherent due process concerns in an exacerbated fashion as well as structural/institutional and cultural limitations. Here three subarguments emerge: First, plea bargaining which inherently relates less to evidence and circumvents fundamental principles of criminal law and procedure, aimed at ensuring the integrity of the process, is likely to yield , inter alia, inaccurate outcomes- the innocence problem. With a less developed legal structure (weak defence in particular) and weak legal culture/rule of law, the problem would be exceptionally formidable in Ethiopia. Second, huge structural and functional limitations of legal institutions- the police, the prosecution, the judiciary, and the defence/legal aid, mean plea bargaining would not fare well. Third, plea bargaining tends to be incompatible with the prevailing legal culture. In America and Western Europe, it is often characterized by problems of fairness and outcome inaccuracy. On the face of weak legal culture/rule of law, it remains to be more so in Ethiopia. While plea bargaining may solve problems of delay and enhance efficiency in many jurisdictions, it is not a universal prescription, though. With jurisdictions like Ethiopia whose legal institutions and legal culture are less developed; whose trial appears to be simple, inexpensive, less utilized and correlates very loosely as an underlying cause of delay, plea bargaining is less likely to offer the desired efficiency gains even at all costs. Conversely, it would be more of a liability than an asset at least in three senses: it is likely to yield inaccurate outcomes- wrongful convictions in an aggravated fashion; put defendant`s rights at greater risk, and leave a room for abuses and corruptions.

In order to achieve binding Government targets towards the decarbonisation of the electricity network, the GB power system is undergoing an unprecedented amount of change. A series of new technologies designed to integrate massive volumes of renewable generation, predominantly in the form of offshore wind, asynchronously connecting to the periphery of the transmission system, are transforming the requirements of the network. This displacement of traditional thermal generation is leading to a significant reduction in system inertia, thus making the task of system operation more challenging. It is therefore deemed necessary to develop tools and technologies that provide far greater insight into the state of the power system in real-time and give rise to methods for improving offline modelling practices through an enhanced understanding of the systems performance. To that extent PMUs are seen as one of the key enablers of the Smart Grid, providing accurate time-synchronised measurements on the state of the power system, allowing the true dynamics of the power system to be captured and analysed. This thesis provides an analysis of the existing PMU deployment on the GB transmission system with a view to the future system monitoring requirements. A critical evaluation and comparison is also provided on the suitability of a University based Low Voltage PMU network to further enhance the visibility of the GB system. In addition a novel event detection algorithm based on Detrended Fluctuation Analysis is developed and demonstrated, designed to determine the exact start time of a transmission event, as well as the suitability of such an event for additional transmission system analysis, namely inertia estimation. Finally, a reliable method for the estimation of total system inertia is proposed that includes an estimate of the contribution from residual sources, of which there is currently no visibility. The proposed method identifies the importance of regional inertia and its impact to the operation of the GB transmission system.