In South African classrooms a strong emphasis is placed on assessing learners by means of portfolios. Through the utilisation of portfolios it is envisaged that learner growth and development should be enhanced in order for learners to become expert learners who are strategic, self-regulated and self-reflecting. This study aimed to determine how effective the implementation of portfolio assessment presently is, and if necessary, to develop a model that could improve the implementation of portfolio assessment in the Senior Phase, Grade 9 in particular. By means of explanatory mixed method research through the completion of questionnaires by 369 learners and 88 educators, and focus group interviews conducted with 36 of the 88 educators from the Sedibeng West District, disconcerting results were revealed. It appeared that educators are not equipped with adequate knowledge and skills to implement portfolio assessment in order to enhance learner growth and development. Based on the disturbing findings, a model was designed to highlight the processes and components involved in the successful implementation of portfolio assessment. As no evidence of any other model to improve the implementation of portfolio assessment at school level could be located, the contribution of this study lies in the development of a tool that could be utilized by the Department of Education to train educators to become effective implementers of portfolio assessment. / Thesis (Ph.D. (Education))--North-West University, Vaal Triangle Campus, 2009.

Nigeria has a huge natural gas reserve, but to date this resource has been largely under-developed. This state of affair has impacted negatively on Nigerias economic potential. In contrast, Alberta has benefitted immensely from its natural gas resource because it has effectively developed same. This thesis advocates the effective development of Nigerias natural gas resources. It examines the current frameworks for the development of natural gas in Alberta and Nigeria and outlines the concepts in the Albertas framework that could be adopted by Nigeria. Three core regimes that promote the effective development of natural gas are utilized for the examination. They are: effective regimes for the acquisition of natural gas rights, for the conservation, and for the utilization of natural gas resources. Given climate change concerns and depletion in natural gas stock capital, this thesis also advocates the sustainable development of natural gas in Nigeria and Alberta.

Coupling between the electric field, magnetic field, and strain of composite materials is achieved when electro-elastic (piezoelectric) and magneto-elastic (piezomagnetic) particles are joined by an elastic matrix. Although the matrix is neither piezoelectric nor piezomagnetic, the strain field in the matrix couples the E field of the piezoelectric phase to the B field of the piezomagnetic phase. This three-phase electro-magneto-elastic composite should have greater ductility and formability than a two-phase composite in which E and B are coupled by directly bonding two ceramic materials with no compliant matrix. A finite element analysis and homogenization of a representative volume element is performed to determine the effective electric, magnetic, mechanical, and coupled-field properties of an elastic (epoxy) matrix reinforced with piezoelectric and piezomagnetic fibers as functions of the phase volume fractions, the fiber (or particle) shapes, the fiber arrangements in the unit cell, and the fiber material properties with special emphasis on the symmetry properties of the fibers and the poling directions of the piezoelectric and piezomagnetic fibers. The effective magnetoelectric moduli of this three-phase composite are, however, less than the effective magnetoelectric coefficients of a two-phase piezoelectric/piezomagnetic composite, because the epoxy matrix is not stiff enough to transfer significant strains between the piezomagnetic and piezoelectric fibers.

A gauged SU(4) flavor symmetric hadronic Lagrangian with empirical hadron masses is constructed to study charmonium absorption and charmed hadron production in hadronic reactions. For the coupling constants, empirical values are used if available. Otherwise, they are determined from known coupling constants using the SU(4) relations. To take into account the finite sizes of hadrons, form factors are introduced at strong interaction vertices with empirical cutoff parameters. For J/ψabsorption by nucleons, we have included both two-and three-body final states and find that with a cutoff parameter of 1 GeV at interaction vertices involving charm hadrons, the cross section is at most 5 mb and is consistent with that extracted from J/ψproduction from both photo-and proton-nucleus reactions. We have also evaluated the cross sections for charmed hadron production from pion and rho meson interactions with nucleons. With the same cutoff parameter of 1 GeV at interaction vertices, we find that these cross sections have values of a few tenths of mb and are dominated bythe s-channel nucleon pole diagram. For charmed hadron production from proton-proton reactions, their cross sections including bothtwo-andthree-body final states are about 1 batcenter-of-mass energyof 11.5 GeV, which is comparable to the measured inclusive cross section in these reactions.Including photon as a U(1) gauge particle, we have extended the model to study charmed hadron production in photon-proton reactions with both two-and three-body final states included. For form factors, an overall one is introduced in each processin order to maintain the gauge invariance of the total amplitude. Fitting the cutoff parameter in the form factor to the measured total cross section for charmed hadron production in photon-proton reactions at a center-of-mass energy of 6 GeV, the ratio of the cross sections for two-body and three-body final states is consistent with available experimental data.This result is further compared with predictions from the leading-order perturbative QCD calculation. Knowledge of the cross sections for charmonium absorption byhadrons and for charmed hadron production in hadronic reactions is essential for understanding charm production in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC), where a quark-gluon plasma is expected to be formed during the initial hot dense stage.

<p>Delays in seeking effective treatment for tuberculosis increase the level of disease morbidity and mortality rate as well as the risk of its transmission in the community (WHO, 2006b). In Somalia, Tuberculosis (TB) remains one of the greatest health threats as it is the leading cause of death in the economically active age groups and in people living with HIV/AIDS (WHO, 2004). This study was carried out with the aim of determining factors influencing delays in seeking TB treatment in Belet-Weyne district.</p>

Plastic deformation processes transform material fromas-received state to products meeting certain requirements inproperties, microstructure and shape. To achieve thistransformation, the relationship between material response andprocess conditions should be understood. This is usuallycomplicated by the complex conditions describing the actualprocess. Numerous techniques including empirical, physical,analytical and numerical can be employed. In this thesis, numerical technique supported by lab- andfull-scale experiments has been employed to analyse the formingparameters. The first part of the thesis is focused on the useof such parameters to predict occurrence of material poresduring manufacturing of bearing rings. The second part dealswith the influence of forming parameters on the grain sizeduring fabrication of large copper canisters for encapsulationof nuclear waste. The primary task has been to study with thehelp of commercial FE-codes the magnitude and distribution offorming parameters such as accumulated effective strain,temperature, instantaneous hydrostatic pressure and materialflow at different stages of the forming process. In the firstpart, two types of ring manufacturing routes, which result inpore free and pore loaded rings are studied and compared.Material elements located in different areas of the workpiecehave been traced throughout the process. Results of theaccumulated strain and instant hydrostatic pressure have beenanalysed and presented in pressure-strain space. It’sassumed that high hydrostatic pressures together with higheffective strains are favourable for pore closure. Area of theworkpiece with unfavourable parameters have been identified andcompared with ultrasonic test results. Good agreement has beenobtained. Based on the results of this analysis, a new conceptfor avoiding pores in manufacturing of yet heavier rings hasbeen presented. The concept proposes a lighter upsetting in theinitial stage of the process and a more efficient piercingwhich results in higher hydrostatic pressure and bigger andbetter distributed effective strain. In the second part of the thesis, the influence of formingparameters such as effective strain and temperature on thefinal grain size of the product has been studied in laboratoryscale. As-cast billets of cylindrical shape were extruded atdifferent temperatures and reductions. It has been shown thatthe grain size in the final product should be small in order toenable ultrasonic tests and to guarantee resistance towardscreep and corrosion. Simulations for different materialelements located at different distances from the axis ofsymmetry of the initial cylindrical workpiece have been carriedout. In this way, the parameters describing the deformationhistory of the elements have been determined as functions oftime. Experimentally obtained pre- and post deformation grainsize in the corresponding locations of the material weredetermined. It’s concluded that low temperature coupledwith high effective strain are conducive for obtaining a smallgrain size. Based on the beneficial conditions for extrusion ofcopper, a more detailed FE-analysis of a full-scale industrialprocess is carried out. A coarse-grained cast ingot of purecopper is heated and by upset forging formed into a cylinder,which is then punched into a hollow blank for subsequentextrusion. The blank is extruded over a mandrel through a45-degree semi-angle die. Accumulated effective strain andtemperatureas functions of the tubular wall thickness havebeen studied at five different locations along the tubularaxis. Forming load requirement as function of tool displacementfor each stage of the process has been determined. Strain andtemperature levels obtained have been related to the grain sizeinterval obtained in the earlier work. It has been concludedthat the levels reached are within the interval that ensures asmall grain size. A similar analysis has been carried out forforging of large copper lids and bottoms. Die designmodifications to improve the grain size in the lid and tooptimise the forging process with respect to forging load andmaterial yield have been proposed. A method requiring a smallforging load for fabrication of the lids has been analysed <b>Keywords:</b>Pores; grain size; low forging load; effective strain;temperature; hydrostatic pressure; extrusion; forging;canister; lid; rings

As a new economy emerges, driven mainly by information technology, we have seen global expansion and prosperous development from the United States. During the last 10 years, research into the increasingly important issues posed by globalization has been carried out in all divisions of the social sciences. As a widely accepted and used concept, however, the word ¡§globalization¡¨ does not guarantee a greater understanding of the world. An existing analytical structure still dominates studies of globalization, and it reveals that current standpoints and mindsets of specific academic disciplines have caused many debates. For example, Held et al (2001¡G3-19) proposed five major controversial globalization issues worthy of study: ¡§conceptualization of globalization¡¨, ¡§causal relationships of globalization¡¨, ¡§definition of the globalization period¡¨, ¡§impact and influence of globalization¡¨, and ¡§trace the development of globalization¡¨. This study focuses on how Taiwan¡¦s science and industrial parks affect Taiwan¡¦s domestic economy and vision with their positioning, transformation, and future development in the competitive global market. China¡¦s gigantic and attractive market and Taiwan¡¦s current political limitations mean that globalization and regional coopetition are indivisible issues for the purposes of this research. Science parks in Asia have become a fast-rising clustering phenomenon as the largest in the world in this new century, and one result has been Taiwan¡¦s success in the global electronics (wafer fab) industry. Currently there are three major science (industrial) parks in Taiwan, located (by order of establishment) in Hsin-chu, Tainan, and Taichung. All three are important bases of Taiwan¡¦s scientific industry. The contribution of these parks to Taiwan¡¦s GDP has increased in each of the 26 years of their development. This study aims to reconstruct the competition model of Taiwan¡¦s science parks from the view point of data processing. This research will also analyze the maintenance of Taiwan¡¦s economic advantages and influence of these government-supported parks¡¦ development mechanism on the nation¡¦s economy in the midst of a fast-changing global business environment, in the hope of continuous, excellent innovation and performance.

The purpose of this research is to develop a new approach to estimate the effective leakage area using the inverse modeling process as an alternative to the blower door test. An actual office building, which is the head quarter of Energy Efficiency Hub, was used as an example case in this study. The main principle of the inverse modeling process is comparing the real monitor boiler gas consumption with the result calculated from the EnergyPlus model with a dynamic infiltration rate input to find the best estimation of the parameter of effective leakage area (ELA). This thesis considers only the feasibility of replacing the blower door test with the calibration approach, so rather than attempting an automated calibration process based on inverse modeling we deal with generating a first estimate and consider the role of model uncertainties that would make the proposed method less feasible. There are five steps of the whole process. First, we need to customize our own actual weather data (AMY) needed by the energy model (EnergyPlus model), which can help increase our quality of the result. Second, create the building energy model in EnergyPlus. Third, create a multi-zone model using CONTAM with different ELA estimation of each facade to calculate the dynamic infiltration rate of each ELA estimate. Fourth, input the dynamic infiltration rate got from the CONTAM model to EnergyPlus model and output the boiler energy consumption. Fifth, compare the boiler gas consumption from the model and the real monitor data and find the best match between the two and the corresponding ELA, which gives the best estimate from the whole inverse modeling process. From the simulation result comparison, the best estimation of the total building ELA from the inverse modeling process is the 23437cm2 at 4pa, while the result from the blower door test is 10483cm2 at 4pa. Because of the insufficient information of the building and also the uncertainty of the input parameters, the study has not led to a definite statement whether the proposed calibration of the ELA with consumption data can replace a blower door test to get an equally valid or even better ELA estimate, but it looks feasible. As this this case study is done in a deterministic context, the full feasibility test should be conducted under uncertainty. A first step towards this will talk be discussed in chapter 4.

The central line-depths of absorption lines depend upon stellar temperature. By dividing the central line-depth of such a line with a central line-depth independent of temperature, a thermometer of relative star temperatures is obtained in the form of a line-depth ratio (LDR), once it is related to an effective temperature scale. Such thermometers are known to give precise results which is why the method is pursued. The purpose of this work is to rank LDRs according to a set of criteria to find the most suitable ratio to measure temperature. This is done based on a set of LDRs measured for a large sample of dwarf stars with known effective temperature, atmospheric pressure and chemical composition. Numerous LDRs are eliminated because their temperature dependence are limited to a short temperature interval. Further LDRs are eliminated due to dependence on the atmospheric pressure and chemical composition of the LDR. The remaining LDRs are ranked based on the strength of temperature dependence, the fit of the representative polynomial to the data points and the number of data points available. The best ranked LDR provides a temperature resolution smaller than 10 K over a temperature interval of 4500-6250 K, assuming an uncertainty in LDR of 0.01.

Solid oxide fuel cells with graded electrodes consisting of multiple composite layers yield generally lower polarization resistances than single layer composite electrodes. Optimization of the performance of solid oxide fuel cells with graded electrode composition and/or microstructure requires an evaluation of both the three phase boundary length per unit volume and the effective diffusion coefficient in order to provide insight into how these properties vary over the design space. A numerical methodology for studying the three phase boundary length and effective diffusivity in composite electrode layers with controlled properties is developed. A three dimensional solid model of a sintered composite electrode is generated for which the mean particle diameter, composition, and total porosity may be specified as independent variables. The total three phase boundary length for the modeled electrode is calculated and tomographic methods are used to estimate the fraction of this length over which the electrochemical reactions can theoretically occur. Furthermore, the open porosity of the modeled electrode is identified and the effective diffusion coefficient is extracted from the solution of the concentration of the diffusing species within the open porosity. Selected example electrode models are used to illustrate the application of the methods developed, and the resulting connected three phase boundary length and diffusion coefficients are compared. A significant result is the need for thickness-specific effective diffusivity to be determined, rather than the general volume averaged property, for electrodes with porosity between the upper and lower percolation thresholds. As the demand for current increases, more of the connected three phase boundaries become active, and therefore a greater fraction of the electrode layer is utilized for a given geometry, resulting in a higher apparent effective diffusivity compared to the same electrode geometry operating at a lower current. The methods developed in this work may be used within a macroscopic electrode performance model to investigate optimal designs for solid oxide fuel cell electrodes with stepwise graded composition and/or microstructure.