Analysis, design, fabrication and testing of an optical tip clearance sensor

Analyses and the design, fabrication, and testing of an optical tip clearance sensor with intended application in aircraft propulsion control systems are reported. The design of a sensor test rig, evaluation of optical sensor components at elevated temperatures, sensor design principles, sensor test results at room temperature, and estimations of sensor accuracy at temperatures of an aircraft engine environment are discussed. Room temperature testing indicated possible measurement accuracies of less than 12.7 microns (0.5 mils). Ways to improve performance at engine operating temperatures are recommended. The potential of this tip clearance sensor is assessed

Complementary Education Programme and the opportunity to learn in the Northern Region of Ghana

This study seeks to critically investigate the contribution of the School for Life (SfL) model of complementary education programme (CEP) in providing access to quality basic education in the Northern Region of Ghana. In so doing, it aims to examine the linkage between the SfL curriculum and pedagogy, and that of the Ghanaian lower primary school. This will enable a better understanding of the knowledge and skills that CEP graduates attain to enable them to integrate into formal education. The study is set against the background of the call for a replication of the SfL model as a mechanism for providing basic education to all marginalized communities. It is conducted using qualitative and quantitative approaches that fully capture the perspectives, experiences and learning achievements of pupils and other actors associated with both the complementary and formal education sectors in the Northern Region. The study examines the planned, implemented and received curricula of the two systems analysing them within a social constructivist framework. Implicit in this analysis is a comparison of the two curricula. This thesis shows that SfL‘s CEP is not formally structured to meet the requirements of the formal school curriculum. The curriculum materials and training offered to the facilitators do not make mention of the formal school curriculum. SfL has a restrictive focus on literacy and numeracy instruction delivered solely through the mother tongue of the pupils utilising learner centred approaches. Meanwhile the formal school curriculum lacks a clear focus and is embedded within an ambiguous language policy that allows teachers to code switch at their discretion. While the two curricula share similar characteristics of locally relevant themes or topics, the SfL curriculum is functionally relevant as it is designed to meet the social economic lives of the learners and their communities. The study also shows SfL graduates in formal school performing at almost the same level as pupils who enrolled in formal school through the regular route. Thus while SfL graduates miss the first three years of primary schooling, once they enrol in grade 4, there is no significant difference between the performances of the two sets of students

The mediating effect of homework between self-regulated learning and science achievement.

Homework has been shown to have a significant, positive effect on student achievement and grades, particularly at the secondary level (Cooper, Robinson, & Patall, 2006). However, homework completion and its effect on grades is controlled within the realm of the student and its success as a learning strategy depends on many things including the students’ interest in the subject, their confidence, the time they have to complete it, gender and other factors within the home such as parent education level and parent involvement (Trautwein & Ludtke, 2007; J. Xu, 2007; J. Xu, Corno, Lyn, 2006). Through the work of Eccles (2002) and Trautwein (2006), homework research has focused heavily on students’ affective beliefs and their relevance. Expectancy-Value theory (Eccles, 2002) and self-efficacy theory (Bandura, 1997) identify student self-confidence and valuation of the subject as integral components of academic motivation and Trautwein (2006) places them as antecedents to homework factors in his model of homework. However, causality among the variables has been unstudied and thus a method of analysis needed to be used that could confirm the placement of these variables in a causal sequence while at the same time demonstrate their importance to homework\u27s relevance. It was the intent of this research to explore the causal relationship among the homework model factors of student positive affect towards science, student valuation of science, self-confidence in science, gender, parent education level, and self-confidence in science on science achievement in U.S. eighth-graders. With specific foci on those above variables involved indirectly in the relationship between gender, parent education level and time spent on homework, as well as the indirect effect of time spent on homework between the affective variables and achievement. Results revealed a significant indirect effect of gender on time spent on homework, reflecting complete mediation, through the affective variables of student positive affect towards science, student valuation of science, self-confidence in science. On the other hand, the affective variables act as partial mediators between parent education level and time spent on homework as both the indirect and direct effects were significant. Indications here are that there may be other unknown variables at work that are not studied in the current research. In addition, time spent on homework was a significant mediating variable between all of the affective variables and achievement. Conclusions and recommendations are made that homework does play a significant role in student achievement in science when the affective characteristics associated with self-regulatory learning are considered. Further research is recommended particularly involving better characterization of the homework construct

Investigation of Vitamin D Metabolites using Different Ion Mobility-Mass Spectrometry (IM-MS) Methods

https://tigerprints.clemson.edu/csrp/1000/thumbnail.jp

Investigation of Vitamin D Metabolites using Different Ion Mobility-Mass Spectrometry (IM-MS) Methods

https://tigerprints.clemson.edu/csrp/1012/thumbnail.jp

Influence of rubbing on rotor dynamics, part 1

The results of analytical and experimental research on rotor-to-stationary element rubbing in rotating machines are presented. A characterization of physical phenomena associated with rubbing, as well as a literature survey on the subject of rub is given. The experimental results were obtained from two rubbing rotor rigs: one, which dynamically simulates the space shuttle main engine high pressure fuel turbopump (HPFTP), and the second one, much simpler, a two-mode rotor rig, designed for more generic studies on rotor-to-stator rubbing. Two areas were studied: generic rotor-to-stator rub-related dynamic phenomena affecting rotating machine behavior and applications to the space shuttle HPFTP. An outline of application of dynamic stiffness methodology for identification of rotor/bearing system modal parameters is given. The mathematical model of rotor/bearing/seal system under rub condition is given. The computer program was developed to calculate rotor responses. Compared with experimental results the computed results prove an adequacy of the model

Sigma-model soliton intersections from exceptional calibrations

A first-order `BPS' equation is obtained for 1/8 supersymmetric intersections of soliton-membranes (lumps) of supersymmetric (4+1)-dimensional massless sigma models, and a special non-singular solution is found that preserves 1/4 supersymmetry. For 4-dimensional hyper-K\"ahler target spaces ($HK_4$) the BPS equation is shown to be the low-energy limit of the equation for a Cayley-calibrated 4-surface in \bE^4\times HK_4. Similar first-order equations are found for stationary intersections of Q-lump-membranes of the massive sigma model, but now generic solutions preserve either 1/8 supersymmetry or no supersymmetry, depending on the time orientation.Comment: 21 pages. Version 3: Minor corrections and one further reference: version published in JHE

Modeling of Heat Transfer in 2D SLAB

Heat transfer in slab is a very important factor especially in the Africa continent. This work modeled the heat transfer in a 2D Slab. It used the Finite Difference Method (FDM) technique. Lines of code were written in Octave and can also be executed in Mat Lab and graph generated. KEYWORDS: finite difference method (FDM), heat, 2d slab, modelin

Climate and soil factors influencing seedling recruitment of plant species used for dryland restoration

Land degradation affects 10–20% of drylands globally. Intensive land use and management, largescale disturbances such as extractive operations, and global climate change, have contributed to degradation of these systems worldwide. Restoring these damaged environments is critical to improving ecosystem services and functions, conserve biodiversity, and contribute to climate resilience, food security, and landscape sustainability. Here, we present a case study on plant species of the mining intensive semi-arid Pilbara region in Western Australia that examines the effects of climate and soil factors on the restoration of drylands. We analysed the effects of a range of rainfall and temperature scenarios and the use of alternative soil materials on seedling recruitment of key native plant species from this area. Experimental studies were conducted in controlled environment facilities where conditions simulated those found in the Pilbara. Soil from topsoil (T) stockpiles and waste materials (W) from an active mine site were mixed at different proportions (100% T, 100% W, and two mixes of topsoil and waste at 50 : 50 and 25 : 75 ratios) and used as growth media. Our results showed that seedling recruitment was highly dependent on soil moisture and emergence was generally higher in the topsoil, which had the highest available water content. In general, responses to the climate scenarios differed significantly among the native species which suggest that future climate scenarios of increasing drought might affect not only seedling recruitment but also diversity and structure of native plant communities. The use of waste materials from mining operations as growth media could be an alternative to the limited topsoil. However, in the early stages of plant establishment successful seedling recruitment can be challenging in the absence of water. These limitations could be overcome by using soil amendments but the cost associated to these solutions at large landscape scales needs to be assessed and proven to be economically feasible