In the current global climate of declining fossil fuel reserves and due to the impact of industry on the natural environment, industrial sustainability is becoming ever more important. However, sustainability is quite a vague concept for many, and there are a range of interpretations of the word. If the resource efficiency of a factory is taken as a measure of its sustainability, then the concept becomes better defined and quantifiable. In order to analyse the resource efficiency of a factory and suggest improvements, all flows through the manufacturing system need to be modelled. However the factory is a complex environment, there is a wide variation in the quality levels of energy as well as the composition of material flows in the system. The research presented in this thesis shows how the thermodynamics-based concept of ‘exergy’ can be used to quantify the resource efficiency of a factory. The factory is considered an ‘integrated system’, meaning it is composed of the building and the production processes, both interacting with each other. This is supported by three case studies in different industries that demonstrate the practical application of the approach. A review of literature identified that it was appropriate to develop a novel approach that combined exergy analysis with the integrated view of the factory. Such an approach would allow a ‘holistic’ assessment of resource efficiency for different technology options possibly employable. The development of the approach and its illustration through practical case studies is the main contribution of the work presented. Three case studies, when viewed together, illustrate all aspects of the novel exergy based resource accounting approach. The first case study is that of an engine production line, in which the resource efficiency of this part of the factory is analysed for different energy system options relating to heating ventilation and air conditioning. Firstly, the baseline is compared with the use of a solar photovoltaic array to generate electricity, and then a heat recovery unit is considered. Finally, both of these options were used together, and here it is found that the non-renewable exergy supply and exergy destruction are reduced by 51.6% and 49.2% respectively. The second case study is that of a jaggery (a sugar substitute) production line. The exergy efficiency of the process is calculated based on varying the operating temperature of the jaggery furnace. The case study describes the modelling of al flows through the jaggery process in terms of exergy. Since this is the first example of an exergy analysis of a jaggery process, it can be considered a minor contribution of the work. An imaginary secondary process that could utilize the waste heat from the jaggery process is considered in order to illustrate the application of the approach to industrial symbiosis. The non-renewable exergy supply and exergy destruction are determined for the baseline and the alternative option. The goal of this case study is not to present a thermally optimized design; rather it illustrates how the exergy concept can be used to assess the impact of changes to individual process operations on the overall efficiency in industrial symbiosis. When considering natural resource consumption in manufacturing, accounting for clean water consumption is increasingly important. Therefore, a holistic methodology for resource accounting in factories must be able to account for water efficiency as well. The third case study is that of a food production facility where the water supply and effluent are modelled in terms of exergy. A review of relevant literature shows that previously, the exergy content of only natural water bodies and urban wastewater had been quantified. To the author’s knowledge, this is the first example of applying this methodology of modelling water flows in a manufacturing context. The results show that due to a high amount of organic content in food process effluent, there is significant recoverable exergy in it. Therefore, a hypothetical water treatment process was assumed to estimate the possible savings in exergy consumption. The results show that at least a net 4.1% savings in terms of exergy could be possible if anaerobic digestion water treatment was employed. This result can be significant for the UK since the food sector forms a significant portion of the industry in the country. Towards the end of the thesis, a qualitative study is also presented that aims to evaluate the practical utility of the approach for the industry. A mixed method approach was used to acquire data from experts in the field and analyse their responses. The exergy based resource accounting method developed in this thesis was first presented to them before acquiring the responses. A unanimous view emerged that the developed exergy based factory resource accounting methodology has good potential to benefit industrial sustainability. However, they also agreed that exergy was too complex a concept to be currently widely applied in practice. To this effect, measures that could help overcome this barrier to its practical application were presented which form part of future work.

Now a days, there is lot of alternatives available, which provides green and renewable energy. Through these alternatives, the consumer’s demand for energy is being satisfied. It is important to use the available energy in a systematic and efficient way so that there are many benefits. The purpose of this study is to briefly identify the various prospects, problems, and policies for energy efficiency in industries. Basis of purpose on the negative impacts caused due to the increased use of energy consumption in industries. This literature study is based from practical examples of industries, industrial applications and other new technology. As the electric motor system operates most of the industrial processes, the electricity consumption of motors in industries accounts for two thirds of total energy consumption. Influencing energy efficiency in industries provides substantial advantages. Various motor applications such as pumps, fans, air compressors, cooling compressors, variable speed drives is studied for their operation and working conditions. The utilization of energy efficient technologies to a greater extent can perceive savings to the industries. In spite of being aware of potentials of using energy efficient technologies in industries, energy efficient technologies are not widely used. A barrier to energy efficiency is explained as a practice that inhibits the industrial decision of being efficient in terms of energy and finance. The barriers consent with energy efficiency in industries is fair enough to be considered, while compromising energy for temporary prosperity is not upright. Influence of increased energy efficiency in market areas need coordination of all industries and commercial area throughout the country. The coordination between the industries and commercial sectors can be closely achieved by raising energy policies and energy regulations. The energy efficient policies are considered as cognizance for market transformation and this can maintain the industry, the environment, and the energy. The options available for market transformation are enormous. It is suggested to implement the energy efficient policies as energy efficiency is important for sustainable future. By adopting the right policy, at right situation can provide enormous benefits to the process, industry, and nation. A basis of energy efficiency in industrial application can provide potential energy savings for the present and future industrial situation. This can provide a balance between INDUSTRY-ENVIRONMENT-ENERGY.

This thesis is focused on local polynomial smoothers of the conditional vari- ance function in a heteroscedastic nonparametric regression model. Both mean and variance functions are assumed to be smooth, but neither is assumed to be in a parametric family. The basic idea is to apply a local linear regression to squa- red residuals. This method, as we have shown, has high minimax efficiency and it is fully adaptive to the unknown conditional mean function. However, the local linear estimator may give negative values in finite samples which makes variance estimation impossible. Hence Xu and Phillips proposed a new variance estimator that is asymptotically equivalent to the local linear estimator for interior points but is guaranteed to be non-negative. We also established asymptotic results of both estimators for boundary points and proved better asymptotic behavior of the local linear estimator. That motivated us to propose a modification of the local li- near estimator that guarantees non-negativity. Finally, simulations are conducted to evaluate the finite sample performances of the mentioned estimators.

Background and objectives: In 2006 Shinya Yamanaka successfully reprogrammed mouse fibroblasts back to an embryonic stem cell-like state (called induced pluripotent cells, iPS cells) using retrovirus to introduce four genes that encode critical transcription factor proteins (Oct4, Sox2, KLF4, and c-Myc). This ability to reprogram has promising future applications in clinical and biomedical research for study of diseases, development of candidate drugs and to support therapeutic treatments in regenerative medicine. However, the clinical applications have to meet GMP requirements without the risk of insertional mutagenesis associated with retrovirus. Chromatin modifying agents are widely used in many protocols to generate iPS cells and culture of blood CD34+ cells with chromatin-modifying agents can lead to an increase in marrow repopulating cells and in the case of valproic acid increased erythroid cell colony formation. We undertook research to help understand what effects these reagents have on mobilised peripheral blood (mPB) CD34+ cells and optimised the expansion medium protocol to facilitate reprogramming work. This project aims to utilize peripheral blood mononuclear cells (MNC), one of the most easily accessible tissues to generate iPS cells using an efficient non-viral, feeder cell free methodology, with the ultimate goal of moving this methodology towards clinical use. Materials and Methods: G-CSF mobilised peripheral blood, buffy coat, cord blood and fetal liver were obtained from patients and donors under informed consent and ethics committee approval. Haematopoietic stem/progenitor cells CD34+ or CD133+) isolated by magnetic separation were flow cytometry sorted into CD34+/CD133+, CD34+/CD133-, and CD34-/CD133+ sub-populations and their lineage potential were assessed in colony forming unit assays. The effect of epigenetic modifiers valproic acid and 5-aza-2-deoxycytidine used singly or in combination with each other and with IL3 on phenotype and lineage potential of cultured CD34+ cells from mobilised peripheral blood were assessed by flow cytometry and colony-forming unit assays. Prior to reprogramming mononuclear cells from peripheral blood or CD34+ cells from blood were expanded in culture medium supplemented with stem cell factor (SCF), Fms-related tyrosine kinase 3 ligand (Flt3L) and Interleukin- 3 (IL-3) for several days. Actively proliferating cells were reprogrammed by electroporation using episomal vectors with an oriP/EBNA-1 backbone to deliver five reprogramming genes, Oct4, Sox2, Lin28, L-Myc, and Klf4. Electroporated cells were seeded onto matrigel coated plates immediately after transfection or were reseeded after three days’ culture. Subsequently, cells were cultured in specific medium on different days. When iPS colonies appeared, they were picked and cultured as for ES cells. Once established, iPS cell lines were immunophenotyped using flow cytometry and immunofluorescence and their potential to differentiate into the three germ layers was assessed in vitro. Results and Conclusion: The largest subpopulation of CD34+ cells was CD34+/CD133+ population which was essentially committed to myeloid colony production, while much smaller CD34+/CD133- subpopulation had a greater capacity to generate erythroid colonies. Optimised cytokine cocktail for expansion of CD34+ cells included IL-3, important in improving expansion and maintaining functionality of CD34+ cells. The optimised cytokine cocktail comprised 100 ng/ml SCF, 10 ng/ml Flt3L, and 20 ng/ml IL-3, which maintained CD34+ cells and MNC in an active proliferating state. In addition, valproic acid and IL3 were found to act synergistically, to increase the numbers of CD34+/CD36+ positive cells. However, we found that an apparent increase in red cell colony formation actually resulted from a decrease in white cell colonies, so no overall increase in red cell colonies was seen when equivalent numbers of CD34+ cells were plated. Proliferating MNC maintained in optimised cytokine cocktail were amenable to electroporation for the effective delivery of episomal transcription factors (Oct4, Sox2, Klf4, L-Myc, and Lin28) within a backbone of oriP/EBNA-1. We successfully developed an efficient and simple method for reprogramming MNC from fresh or frozen samples to generate induced pluripotent cells using episomal vectors in a feeder-free system without any requirement for small molecules and the highest reprogramming efficiency is 0.033% (65 colonies from 2 ◊ 105 seeding MNC). The cytokine cocktail and reprogramming methods work better in CD34+ cells from cord blood or fetal liver, and we obtained 148 iPS colonies from 105 seeding cells (0.148%) at most. In addition, fibroblasts from adult and fetal liver can be successfully reprogrammed using the same reprogramming method. The use of episomal vectors with an oriP/EBNA-1 backbone to deliver reprogramming genes, and efficient electroporation were the most important factors in efficiency of the reprogramming process. In addition, it is pivotal to initiate transfection when cells are actively proliferating. The iPS cell lines we generated maintained the successful expression of ES markers including Oct4, Nanog, SSEA3. SSEA4, TRA-1-60 and TRA-1-81, and had the capacity to successfully differentiate into cell types of ectoderm, mesoderm and endoderm layers in vitro.

In this thesis, multicell coordination for wireless cellular networks is studied, whereby various approaches have been conducted to tackle this issue. Firstly, the coverage probability and e ective capacity in downlink multiple-input multiple-output (MIMO) cellular system are considered. Two scenarios are investigated; in the rst scenario, it is assumed that the system employs distance-based fractional power control with no multicell coordination. For the second scenario, it is assumed that the system implements multicell coordinated beamforming so as to cancel inter-cell interference. The base stations (BS) are modelled as randomly uniformly distributed in the area according to Poisson point process (PPP). Using tools from stochastic geometry, tractable, analytical expressions for coverage probability and e ective capacity are derived for both scenarios. Secondly, an adaptive strategy for inter-cell interference cancellation and coordination is proposed for downlink multicarrier cellular random networks. The adaptive strategy coordinates and cancels the interference on the both frequency and spatial domains. Based on this adaptive strategy, two interference management schemes have been proposed. The adaptation process is implemented based on measured instantaneous signal-to-interference and noise ratio (SINR) of the considered user. Furthermore, the locations of base stations BSs are modelled as an independent spatial PPP. Using tools from stochastic geometry, the proposed schemes have been analytically evaluated. Analytical expressions for coverage probability are derived for both schemes. In addition, an expression for average rate has been derived using the coverage probability analysis. Thirdly, low complexity algorithms for user scheduling have been proposed for coordinated MIMO multicell network. The algorithms consist of two stages: multicell scheduling stage and precoding stage. The algorithm works on sequential distributive manner. Two variants of multicell scheduling are proposed. The rst algorithm has less complexity but leads to more di erence in sum rate among cells. While the second algorithm results in better fairness in terms of system performance but causes frequent signalling among the cells. Moreover, the algorithm is extended to multimode selection in addition to the user selection. Finally, an adaptive coordination scheme for energy-effeicient resource allocation has been developed for orthogonal frequency division multiple access (OFDMA) cellular networks. The proposed scheme consists of centralised and distributed stages for allocating resources to cell-edge and cell-centre users, respectively. The optimisation problems are formulated as integer linear fractional and integer linear problems for the first stage and second stages, respectively. The spectral-energy trade-o is analysed under the constraint of fairness among users. In summary, the research work presented in this thesis reveals statistical approach to analyse the multicell coordination in random cellular networks. It also offers insight into the resource allocation and scheduling problems within multicell coordination framework, and how to solve them with a certain objective.

No description available.

Magister Legum - LLM / This study focuses on the impact on service provision arising from uncertainties in the UC Act. There are serious problems with the delivery of basic services in urban areas: including frequent interruptions in water supply, persistent power cuts, uncollected refuse, poor health services and dilapidated infrastructure. The purpose of this study is to highlight specific weaknesses in the UC Act and examine how these contribute to poor service delivery. The specific weaknesses to be examined are the unfettered powers of the minister, lack of legal certainty on powers and functions of UCs, limited revenue generating powers and lack of autonomy in recruiting senior council administration. First, UCs exercise delegated powers from central government. The minister has powers to give directions on matters of policy, suspend, reverse, or rescind council resolutions. There is no legal authority to check and balance the unfettered powers of the minister. Poor service delivery may be attributed in part to the unfettered powers of the minister. Secondly, UCs do not have devolved fiscal powers. As agents of central government, UCs can only levy those taxes and borrow money as authorised by the minister. The limited capacities of UCs to generate own revenue impacts negatively on the capacity of UCs to respond to the needs of the communities they serve. / South Africa

>Magister Scientiae - MSc / This research undertakes to investigate both long-term and short-term investor overreaction on the JSE Limited (JSE) over the period from 1 January 2002 to 31 December 2009. The period covers the restructuring and reform of the JSE in the early 2000s to the end of global financial market crisis in late 2008/2009, which can be regarded as a complete economic cycle. The performances of the winner and loser portfolios are evaluated by assessing their cumulative abnormal returns (CAR) over a 24-month holding period. The test results show no evidence of mean reversion for winner and loser portfolios formed based on prior returns of 12 months or less. However, test results show evidence of significant mean reversion for the winner and loser portfolios constructed based on their prior 24 months and 36 months returns. In addition, the study reveals that the mean reversion is more significant for longer-formation-period portfolios as well as for longer holding periods. The examination of the cumulative loser-winner spreads obtained from the contrarian portfolios based on the constituents’ prior 24 month and 36 month returns indicates that the contrarian returns increase for portfolios formed between 2004 and 2006, and declines thereafter towards the end of the examination period. The deterioration of contrarian returns coincides with the subprime mortgage crisis in 2007 and the subsequent global financial crisis in 2008. This evidence suggests that the degree of mean reversion on the JSE is positively correlated to the South African business cycle.

New and proposed tax relief sections have been added to the Income Tax Act no 58 of 1962 over the past few years and this is an indication that the South African (SA) Government acknowledges that there is considerable investment required, by both SA taxpayers and the SA Government, to go “green” and to save energy. The National Treasury proposed the introduction of section 12L to the Income Tax Act No 58 of 1962 (the Act) in the 2009 Taxation Laws Amendment Act. This will provide an incentive for taxpayers to benefit from energy savings by incurring capital expenditure with the purpose of reducing energy consumption. The idea with the proposed section 12L is that the more energy one saves, the less tax one pays. However, the proposed introduction of section 12L has led to uncertainty as to the process to be followed by a taxpayer, in order to qualify for the allowance. There will be a discussion on whether this notional allowance will be in addition to the allowances and deductions based on actual expenditure incurred in the investment of new green technologies. The objective during the current study is to examine how government should formulate SA legislation in terms of section 12L of the Act to stimulate investment in the conversion of old technologies to new “green” technology. The challenges of improved energy savings will be addressed in the SA context, and compared to similar legislation in China and the United Kingdom (UK). This comparison will identify the gaps, alternatives and possible improvements to the proposed SA section 12L. AFRIKAANS : Nuwe en voorgestelde wetsartikels vir die vermindering van belasting is gedurende die laaste paar jaar ingedien. Dit is ’n aanduiding dat die Suid-Afrikaanse (SA) Regering erken dat aansienlike belegging benodig word om “groen” te raak en om krag te bespaar. Die Nasionale Tesourie het die indiening van artikel 12L in die Inkomste belasting Wet Nr. 58 van 1962 (Die Wet) in die 2009 Belasting Wysigingswet voorgestel. Dit sal as aansporing dien vir belastingbetalers om voordeel te trek uit energiebesparing deur om kapitaaluitgawes wat lei tot die vermindering van kragverbruik aan te gaan. Die idée agter die voorgestelde artikel 12L is dat hoe meer energie ’n mens spaar, hoe minder belasting jy hoef te betaal. Die voorgestelde indiening van wetsartikel 12L lei egter tot onsekerheid oor die proses wat die belatingbetaler moet volg om vir die toelaag te kwalifiseer. Die bespreking sal insluit of hierdie voorgestelde toelaag bykomend sal wees tot die toelae en aftrekkings wat gegrond is op werklike uitgawes wat aangegaan is tydens belegging in die nuwe groen tegnologie. Die doelwit met hierdie studie is om ondersoek in te stel in hoe die regering die SA wetgewing in terme van artikel 12L van die belastingwet moet formuleer om sodoende belegging in die omskakeling van die ou tegnologie na die nuwe “groen” tegnologie te stimuleer. Die uitdaging van energie besparing sal in die SA konteks aangespreek word en vergelyk word met soortgelyke wetgewing in die Verenigde Koningkryk (VK) en China. Die gapings, alternatiewe en moontlike verbeterings in die voorgestelde wetsartikel 12L sal tydens hierdie vergelyking identifiseer word. Copyright 2011, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Du Toit, EF 2011, Energy efficiency savings allowance in South Africa : an international comparison, MCom dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-03062012-113449 / > F12/4/146/gm / Dissertation (MCom)--University of Pretoria, 2012. / Taxation / unrestricted

Market efficiency, based on people acting rationally, has been the dominating finance theory for most of the 20th and 21st Century’s. This classical finance theory is based on assumptions that people are rational, they absorb all available information and maximise utility. This view is outdated; it has been shown that people are in fact irrational and that this could be the cause of anomalies in the market. Behavioural finance takes into account people, and their natural biases. Behavioural finance has integrated classical financial theories and psychological theories to illustrate the way in which irrational people can impact market efficiency. This research looks at the way collective investment scheme manager decision-making can impact market efficiency. Specifically the behavioural biases: overconfidence, over optimism, loss aversion and frame dependence and whether or not collective investment scheme performance is affected by these. This research was carried out using a questionnaire distributed directly to CIS managers and risk-adjusted returns were used in order to allow for comparative results. The results from the questionnaire show evidence that actively managing South African CIS managers do indeed suffer from overconfidence and loss aversion and they do not appear to suffer from frame dependence or over optimism in this research context. There was also evidence showing that managers who suffer from these biases also demonstrated lower investment returns. “The investor’s chief problem, and even his worst enemy, is likely to be himself.” - Benjamin Graham