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This dissertation provides a thorough overview of the use of nonparametric estimation methods for analyzing data collected by complex sampling plans. Applied econometric analysis is often performed using data collected from large-scale surveys, which use complex sampling plans in order to reduce administrative costs and increase the estimation efficiency for subgroups of the population. These sampling plans result in unequal inclusion probabilities across units in the population. If one is interested in estimating descriptive statistics, it is highly recommended that one uses an estimator that weights each observation by the inverse of the unit's probability of being included in the sample. If one is interested in estimating causal effects, a weighted estimator should be used if the sampling criterion is correlated with the error term. The sampling criterion is the variable used to design the sampling scheme. If it is correlated with the error term, sampling is said to be endogenous and, if ignored, leads to inconsistent estimation. I consider three distinct probability weighted estimators: i) a nonparametric kernel regression estimator; ii) a conditional probability distribution function estimator; and iii) a nonparametric instrumental variable regression estimator. / Thesis / Doctor of Philosophy (PhD)

This thesis is missing page 147 in all printed copies. - Digitization Centre / Techniques for accelerating the convergence of multi-variable iterative calculations were studied. The study is mainly concerned with iterations which result from the calculation of recycle processes of complex chemical plants. The conditions for convergence and the existence of the solution of linear and non-linear iterations were obtained. Special attention was given to the asymptotic behaviour of the iterations since, in most cases, they approach geometric progression. The convergence of an Alkylation unit simulation was studied by implementation of the "full matrix" technique for accelerating the rate of convergence. The geometric extrapolation technique was described and applied successfully for accelerating the convergence of the calculation of multi-component distillation columns. / Thesis / Doctor of Philosophy (PhD)

This thesis is missing page 16, no other copies of this thesis have the page. -Digitization Centre / Metasomatism was taken by Goldschmidt (1922) as being metamorphism involving introduction and removal of certain substances, with a corresponding change in the chemistry and mineralogy of the rock concerned. Using this definition, there is strong evidence of metasomatism having played an important role in the transformation of part of the Kamiskotia mafic intrusion from a norite to a greenschist facies rock. The importance of metasomatism has generally proved difficult to evaluate because of disagreement on a quantitative approach to the problem. Two of the approaches suggested in the literature have been employed to characterize the chemical changes accompanying metamorphism of the Kamiskotia complex; one assuming constant volume, the other assuming constant alumina. The latter approach, supported by most recent work in this area (Carmichael, 1970; Korzhinsky, 1964) is favoured. It defines a mobility series that agrees quite well with Korzhinsky's for all elements except iron. It is concluded that metamorphism, of the Kamiskotia norite has been accompanied by significant removal of potash, soda, iron and silica besides the addition of water and carbon dioxide. Reactions, constructed on the basis of mineral relationships observed in thin section combined with the calculated chemical changes are proposed. The source of the metasomatic fluids and the site of deposition of removed material is speculated upon. / Thesis / Bachelor of Science (BSc)

This thesis is missing page 78, the other copies of this thesis do not have the page either. -Digitization Centre / In benzene solution at 10°, 2-butyne and bis(benzonitrile)palladium chloride reacted together to give the Dietl complex [(Me2c2)3PdC12]2. Reaction of this complex with Ph3E (E = P, As, Sb) gave hexamethyl-benzene, 1-vinyl-1,2,3,4,5-pentamethylcyclopentadiene, and 1-(1-chlorovinyl)-1,2,3,4,5-pentamethylcyclopentadiene. The complex was decomposed by hydrazine to the vinylpentamethylcyclopentadiene; with halogen hexamethylbenzene was formed; while lithium aluminum hydride gave largely 1-ethyl-1,2,3,4,5-pentamethylcyclopentadiene. In the presence of o-phenanthroline a new complex was formed, identified as 1-(chloro-(o-phenanthroline)palladium)-vinyl-1,2,3,4,5-pentamethylcyclopentadiene. Similar complexes were obtained with bipyridyl and pyridine. A structure for the Dietl complex is proposed and the mechanisms of some of its reactions are discussed. / Thesis / Master of Science (MS)

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AIDS Dementia Complex (ADC) is a common neurological complication of HIV/AIDS. ADC is characterized by cognitive, behavioral, and motor impairments including slowed thinking, decreased concentration, forgetfulness, apathy, irritability, anxiety, clumsiness, leg weakness, and altered handwriting. Symptoms progress into pronounced verbal and motor slowing, extensive thought disturbances, profound disorientation, hostility, ataxia, incontinence, and eventually a near vegetative state. Presently, no cure is available for ADC. However, treatment with the antiretroviral drug, zidovudine (AZT), has been shown to slow the progression of ADC and improve functioning. Other promising pharmacological treatments under investigation include newer antiretroviral drugs, combination use of protease inhibitors and zidovudine, calcium channel blocking agents, receptor antagonists for excitatory neurotransmitters, and antagonists of cytokines and inflammatory agents. Psychosocial interventions for managing patients in the early stages of ADC focus on preserving independence, promoting self-esteem, and assisting patients to compensate for cognitive changes. During the later stages of ADC, interventions deal with adapting patients' environments to ensure safety and maintain structure, routine, and simplicity. Prompt intervention is essential to improving the quality and length of these patients' lives.

The United States and the People's Republic of China maintain a unique relationship due to the high levels of interdependence between the countries' political, economic, military, and social functions. This association has been complicated in the past by Chinese industrial cyberespionage (CE) carried out against United States organizations and individuals in pursuit of economic advancement. This paper examines the nature of Chinese-American relations and determines whether its features adhere to Robert Keohane and Joseph Nye's theory of complex interdependence in Power and Interdependence. Further, this paper also explores possible reasons for a decline in Chinese CE beginning in mid-2014 and what impact this could have on the two countries' relations moving forward. / Master of Arts / The purpose of this thesis is to examine whether the United States and China have become interdependent through political, economic, military, and social means. Additionally, China has historically spied on and stolen United States’ secrets electronically for their own benefit. This trend began to slow down in mid-2014 and I offer several possible explanations for why this might have happened. Lastly, I conclude by seeing how this decline in Chinese spying reflects on the interdependent relationship between China and the United States.

Thesis (PhD)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: Separation of the metal ions Cu2+, Pb2+, Cd2+ Mn2+, Cr3+, Fe3+ and Zn2+ with poly ethylenediamine tetra-acetic acid (EDTA), ethylenediamine disuccinic acid ([S,S']- EDDS) and ethylenediamine dimalonic acid (EDDM) was performed by Capillary Electrophoresis. The electropherograms obtained by Capillary Electrophoresis were validated with a speciation model Joint Expert Speciation System (JESS). Excellent agreement was observed for the speciation diagrams for these species with the pH curves determined by capillary electrophoresis with those determined by speciation modelling using JESS. The ligands EDDS and EDDM are readily biodegradable. They have been proposed as substitute ligands for EDTA. Detection of the above species was performed using both an electrochemical and a UV detector. The obtained electropherograms were used for the determination of the detection limits of these species. The electrochemical detector has a lower detection limit for these species than the UV detector in conformity with reported literature for these detectors. / AFRIKAANSE OPSOMMING: Skeiding van die metaal ione Cu2+, Pb2+, Cd2+, Cr3+, Fe3+ en Zn2+ met behulp van etileendiamientetra-asyn suur (EDTA), etileendiamiendisuksien suur ([S,S']-EDDS) en etileendiamiendimaleen suur (EDDM) was gedoen deur kapilêre elektroferose. Die elektroferogramme, verkry deur kapilêre elektroferose was gebruik om die spesiasie model "Joint Expert Speciation System (JESS)" te valideer. Uitstekende ooreenstemming was waargeneem vir die verspreidings diagramme van hierdie spesies as 'n funksie van pH wat verkry was deur kapilêre elektroferose met die' wat vasgestel was deur die spesiasie modeleeringsproses van JESS. Die ligande EDDS en EDDM toon onmiddelike biodigradeerbaarheid. Hulle was voorgehou as alternatiewe ligande vir EDTA. Bepaling van die bogenoemde spesies was ook gedoen deur beide elektrochemiese en UV deteksie. Deur gebruik te maak van hierdie detektore was die deteksie limiete van hierdie spesies bepaal. Die elektroochemiese detektor het 'n laer deteksie limiet vir hierdie spesies in vergelyking met die UV detector. Dit stem ooreen met die literatuur vir hierdie detektore.

Thesis (PhD)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: Separation of the metal ions Cu2+, Pb2+, Cd2+ Mn2+, Cr3+, Fe3+ and Zn2+ with poly ethylenediamine tetra-acetic acid (EDTA), ethylenediamine disuccinic acid ([S,S']- EDDS) and ethylenediamine dimalonic acid (EDDM) was performed by Capillary Electrophoresis. The electropherograms obtained by Capillary Electrophoresis were validated with a speciation model Joint Expert Speciation System (JESS). Excellent agreement was observed for the speciation diagrams for these species with the pH curves determined by capillary electrophoresis with those determined by speciation modelling using JESS. The ligands EDDS and EDDM are readily biodegradable. They have been proposed as substitute ligands for EDTA. Detection of the above species was performed using both an electrochemical and a UV detector. The obtained electropherograms were used for the determination of the detection limits of these species. The electrochemical detector has a lower detection limit for these species than the UV detector in conformity with reported literature for these detectors. / AFRIKAANSE OPSOMMING: Skeiding van die metaal ione Cu2+, Pb2+, Cd2+, Cr3+, Fe3+ en Zn2+ met behulp van etileendiamientetra-asyn suur (EDTA), etileendiamiendisuksien suur ([S,S']-EDDS) en etileendiamiendimaleen suur (EDDM) was gedoen deur kapilêre elektroferose. Die elektroferogramme, verkry deur kapilêre elektroferose was gebruik om die spesiasie model "Joint Expert Speciation System (JESS)" te valideer. Uitstekende ooreenstemming was waargeneem vir die verspreidings diagramme van hierdie spesies as 'n funksie van pH wat verkry was deur kapilêre elektroferose met die' wat vasgestel was deur die spesiasie modeleeringsproses van JESS. Die ligande EDDS en EDDM toon onmiddelike biodigradeerbaarheid. Hulle was voorgehou as alternatiewe ligande vir EDT A. Bepaling van die bogenoemde spesies was ook gedoen deur beide elektrochemiese en UV deteksie. Deur gebruik te maak van hierdie detektore was die deteksie limiete van hierdie spesies bepaal. Die elektroochemiese detektor het 'n laer deteksie limiet vir hierdie spesies in vergelyking met die UV detector. Dit stem ooreen met die literatuur vir hierdie detektore.