Mobile phone networks are on the verge of a major breakthrough in terms of the services they offer. At the same time, active networks are being presented as the next step in the evolution of network architecture, with the aim of providing greater functionality within the network but retaining flexibility. At the same time, the 3G revolution seems to be floundering, due to the need to make a financial return on the huge investment tied up in the licences. This thesis seeks to provide a way forward, by investigating the implementation of a novel service that is the provision of video streaming across the mobile network with location dependent advertisement insertion. The work retains flexibility within the network architecture to enable additional services to be evolved and implemented with minimal modification to the nodes. The approach taken is to combine the traditional architecture with active functionality. As a result this thesis describes a novel service, the implementation of a short video service with location dependent advertisement insertion. This enables the provider to generate an income by transporting the service (it is possible for a third party to generate the content instead of the network provider) and by selling the advertisement space. This thesis investigates the implementation issues involved in providing the service and presents a protocol for the operation of it. The impact of this service on other users is also studied with the conclusion being that it does not adversely effect the quality of service of the voice traff ic within the network. In order to investigate the implementation of the protocol, a simulation model was constructed in OPNET [42]. This enabled the operation of the protocol to be tested under artificial conditions using fixed movements, to verify that it operated as specified. Then under more realistic conditions, so as to predict its effect on the other traffic in the network.

Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: Dialog; Learning Gain; Web-Based Evaluations; Empirical Results; Student Motivation; Mathematics education; Model-Tracing Tutors; Tutoring Strategy Evaluation; Intelligent Tutoring. Includes bibliographical references (p. 33-34).

1. Introduction Injury is the fifth leading cause of mortality and morbidity among adults in Iowa. Work-related, or occupational injuries, constitute a substantial proportion of the injury burden in the US. The Bureau of Labor Statistics reports about 4.9 million occupational injuries annually in the US and over 50,000 injuries in Iowa. The aims of this study were to assess: 1) the burden of work-related injuries using an algorithm based on analysis of the external cause of injury (i.e., E-codes) combined with injury registry variables; 2) the magnitude of disability following an occupational injury by assessing Disability Adjusted Life Years and Discharge to Long Term Care; and 3) the burden of short-term disability one year after discharge from a Level I trauma center. 2. Methods/Approach This research consisted of two observational studies of Iowa cases, ages 18-64, reported to the Iowa State Trauma Registry (STR) from January 1st 2007 to December 31st 2010. A retrospective cohort design was used to assess differences in mortality, length of stays, discharge disposition, disability risk and Disability-Adjusted Life Years (DALYs), and their associated risk factors, such as demographic characteristics, nature and severity of injury, pre-hospital and in hospital trauma care (i.e. transport, resuscitation, vascular and airway access, sedative and paralytic drug usage). A prospective follow-up study a cohort of cases discharged from the University of Iowa Resource Trauma Center was used to assess risk factors associated with short-term disabilities one year after discharge. The EuroQol-5 Dimension Questionnaire (EQ-5D) was mailed to the cohort cases, alive one year after discharge, to assess their overall health status and quality of life. The algorithm classified the study population into occupational, “Work-Likely” (WL), and non-work cases. Work-likely was defined based on work-related activities without pay, informal status or self-employed. The registry cases were matched to 2007-2011 death certificates to identify those who died after discharge and to estimate their survival time. Machine learning methods – logistic regression and 10-fold cross validation were used to validate the algorithm. The survival time from injury to death was assessed using Kaplan Meier and Cox regression modeling. The Generalized Linear Modeling, including multinomial regression, was used to analyze the mean length of stay, the risk of discharge to long term care, DALYs and disability risk. 3. Results From 2007 to 2010, there were individuals (ages 18-64) admitted (average 5,614 per year) as trauma cases to hospitals in Iowa. Based on the algorithm, 3,115 (14.0%) were classified as occupational, 847 (3.8%) as WL, and 18,454 (82.2%) were classified as non-work cases. There were notable differences in demographics, farm exposure, and rural residence. The 10-fold cross validation showed a 20% misclassification rate for occupational and 30% for WL. The area under the curve (AUC) of the receiver-operating characteristics (ROC) was measured at 0.66, which is indicative of poor discriminating effect. Overall, occupational and WL cases had better outcomes than non-work cases; they had lower mean lengths of stay and better survival rates, as detected by Kaplan-Meier and Cox regression models. WL had lower survival rates on the Kaplan Meier estimates but the Cox regression contrast statement didn't find any difference in survival between occupational and WL 30 days and one year after discharge. Multinomial regression showed major differences in the risk of discharge to long-term care (LTC) or acute care compared to discharge home between occupational, WL, and non-work cases WL cases had less risk of being discharged to LTC compared to non-work cases. There were no differences observed between occupational and non-work cases. When stratified by occupational status, the predictors of being discharged to Long term care or acute care were different for occupational, WL and non-work cases. For WL, care in Level I&II , injury type, triage mechanism, first ER systolic blood pressure were no longer good predictors of discharge to LTC compared to occupational or non-work cases. Mean DALYs were lower in the occupational (mean= 4.8; 95% CI: 4.7-4.8) and WL (mean 4.4; 95% CI: 4.4-4.7) cases than the non-work cases (mean= 5.2; 95% CI: 5.1-5.2). However, when all other risk factors were accounted for, the occupational cases had a 10% reduction in mean DALYs, and WL a 20% reduction in DALYs compared to non-work cases. When the disability was assessed separately by occupational status, the risk factors associated with disability were completely different. For WL cases, only injury location and ISS were significantly associated with DALYs. Conversely for occupational and non-work cases, injury type, coma, pre-hospital management (i.e. airway, paralytic drugs), and cause of injury were significantly associated with DALYs. The one-year follow-up questionnaire administered to 156 trauma survivors resulted in 72 (46%) valid responses. Of those who responded, 58 (81%) were occupational and 14 (19%) WL cases. Overall, from the EQ-5Dresults, 46% of the respondents reported a disability. There were no major differences in the prevalence of disability between occupational and WL injury cases. However, occupational injury cases were more likely to receive rehabilitation services. 4. Conclusions This study demonstrated the utility of using trauma registry data in epidemiologic research to study occupational injury using a unique algorithm to include informal or self-employed workers. It identified a neglected group of workers subject to occupational injury and subsequent disability.

Bismuth molybdates have long been known as active catalysts for selective oxidation of olefins. There are several phases of bismuth molybdates but only three of them are known to be active for partial oxidation of propylene to acrolein, namely, α, β, and γ bismuth molybdates. A significant amount of work has been carried out and reported in the literature, aiming to understand the reaction mechanisms so as to control the reaction process. It has been revealed that the oxidation reaction follows the redox mechanisms and lattice oxygen plays a key role as the main oxygen source for the reaction and controls the catalyst performance. The properties of the lattice oxygen are influenced by the bulk crystalline structure of the catalyst. Therefore, it is possible that the crystal structure influences the performance of the catalyst in promoting the partial oxidation reaction. However, there appears to be a lack of detailed reports in the literature on the relationship between the bulk crystal structure and the activity and selectivity of the catalyst for the partial oxidation reaction. The work reported in this thesis has been designed to achieve an improved understanding of the catalyst structure in relation to the activity and selectivity of the catalyst for the partial oxidation of propylene to acrolein. / In order to fulfil the objectives of this study, several investigation steps have been taken, namely 1) acquiring and analysing the catalyst structural parameters under real reaction conditions as well as at room temperature by means of neutron diffraction and X-ray diffraction, 2) obtaining kinetics from experimentation using a packed-bed reactor operating under differential reactor mode so as to eliminate the mass diffusion effect, and 3) developing and proposing reaction mechanisms which contain events that occur on the crystalline structure of the catalysts, particularly lattice oxygen, during the reaction. Characterisation of the structure of the catalysts has been carried out by means of In-situ neutron diffraction, which has the ability to probe the crystal structure at atomic level. The structure is characterised under simulated reaction conditions to investigate the dynamics of the crystal structure, particularly lattice oxygen, during the reaction. The In-situ diffraction studies have uncovered the relationship between the crystal structure of bismuth molybdates and their selectivity and activity towards the catalytic partial oxidation of propylene to acrolein. The possible active lattice oxygen in the bismuth molybdate structures has been identified. The active lattice oxygen ions are responsible for maintaining redox balance in the crystal lattice and thus control the catalyst activity and selectivity. Mobile oxygen ions in the three bismuth molybdate crystal phases are different. The mobile oxygen ions are O(1), O(11), and O(12) in the α phase; O(3), O(11), O(16), and O(18) in the β phase; and O(1) and O(5) in the γ phase. / The mobile lattice oxygen ions are proposed to be the source of the oxidising oxygen responsible for the selective oxidation of propylene to acrolein. One common feature of all mobile oxygen ions, from a catalyst crystal structure point of view, is that they are all related to molybdenum ions rather than bismuth ions in the lattice. By modifying the physical and chemical environment of the molybdenum oxide polyhedra, it is possible to modify the catalyst selectivity and activity. The diffraction diagnoses have also shown that molybdenum oxide polyhedra in all bismuth molybdate are unsaturated. In contrast, the bismuth oxide polyhedra are over charged. The co-existence of molybdenum ions that are co-ordinately unsaturated with bismuth ions that are over valence-charged promote the formation of allyl radical such as those found in the partial oxidation of propylene to acrolein. The molybdenum ions become propylene-adsorbing sites while the bismuth ions are the active sites to attract hydrogen from the adsorbed propylene, leading to the formation of the allyl intermediate. Oxygen ions from the mobile lattice oxygen are a more moderate oxidant than molecular oxygen. With their mild activity, the partially oxidised products are the main products such as acrolein and formaldehyde when oxygen ions react with the allyl intermediate while more complete combustion products such as carbon oxides and organic acids become the side products. / Investigation into the kinetics and reaction mechanisms has revealed the aforementioned evidence to support the role of the mobile lattice oxygen ions in the partial oxidation of propylene to acrolein. The kinetic experiments have employed the power rate law to model the kinetic data. The model shows that the reaction orders in propylene and oxygen concentrations are a function of the reaction temperature. The reaction order in propylene increases with reaction temperature, from 0.6 at 300°C to 1.0 at 450°C for all the bismuth molybdate catalysts, while the reaction order in oxygen decreases from 0.6 at 300°C to 0 at 450°C. The activation energies are 99.7, 173, and 97.7 kJ.mol-1 for α-Bi2Mo3O12, β-Bi2Mo2O9, and γ-Bi2MoO6, respectively. The changes in reaction orders with respect to propylene and oxygen indicate that the reaction occurs through the redox mechanisms, using the mobile lattice oxygen. The structural dynamics identified earlier explains the decrease in the acrolein selectivity at high temperatures (ca above 390°C). At these temperatures, the mobile oxygen becomes more mobile and more active. As a result, as the mobility of the oxygen ions increase, their reactivity also increases. The increase in the oxygen reactivity leads to unselective, complete oxidation reaction, forming the complete oxidation products CO2 and H2O. The reduction-reoxidation of bismuth molybdate is controlled by the diffusion of oxygen ions in the lattice, because the reduction sites do not have to be adjacent to the oxidation sites. The oxygen diffusion rate is in turn controlled by how mobile the lattice oxygen ions are. / Hence, the mobile oxygen ions discussed earlier control the catalyst activity in catalysing the reaction of propylene partial oxidation. The examination of several reaction mechanism models has given further evidence that the propylene partial oxidation to acrolein occurs via the redox mechanism. In this mechanism, the rate of acrolein formation depends on the degree of fully oxidised sites in the bismuth molybdate. The oxidised sites affect the apparent reaction orders in propylene and oxygen and thus control the kinetics of partial oxidation of propylene to acrolein. The more easily the reduced catalysts are reoxidised, the more active the catalysts in converting propylene to acrolein. A set of reaction steps has been proposed, which adequately reassembles the reaction mechanism. Side product reactions are also identified and included in the mechanisms. The present thesis has revealed a much detailed insight into the role of lattice oxygen in the catalytic partial oxidation of propylene to acrolein over bismuth molybdates and established the relationship between structure and activity and selectivity of the catalyst. This work has laid a foundation for future catalyst design to be based on structural knowledge of the catalysts.

Student Number : 9900051W - MSc dissertation - School of Chemical and Metallurgical Engineering - Faculty of Engineering and the Built Environment / When specifying materials for use in exhaust systems, it is imperative that they exhibit sufficient corrosion resistance for the specific conditionsto which exhaust components are exposed, since up to 80% of all failures is attributed to corrosion and oxidation. It is therefore neccesary to establish the corrosion behaviour of the materials in conditions and environments to which the exhausts would typically come into contact with. Most car manufacturers, exhaust manufacturers and material providers have specific corrosion testing methods which they use to determine the corrosion resistance of candidate materials, but there appears to be no standard procedure. A summary comparing all the existing systems is given in section 2.7. The corrosion testing methods utilise a wide range of conditions, testing temperatures and stages. However, careful investigation of the tests show some similarities, and it was possible to identify eleven key tests, that cover internal corrosion, external corrosion and oxidation for both diesel and petrol engines. Eight of these tests were used to rank the corrosion and oxidation resistance of selected stainless steels, namely AISI type 304, 321, 409, 434 and DIN 1.4509. It appears that the austenitic stainless steels perform better in the cold end conditions, while the ferritic types are more resistant in the hot end high temperature conditions. Of all the eight test performed, only the electrochemical tests for external corrosion of cold end components did not give reproducible results. The rest of the tests could be used to screen materials for exhaust system applications. In the internal condition of the cold end, the results of the elctrochemical tests indicated that they can be used as a possible replacement for the long exposure tests. The key tests also highlighted the the presence of NH4+ ions in an exhaust gas is benificial to the corrosion resistance od stainless steels in internal cold end application. Its inhibiting effect was more pronounced for the ferritic stainless steels. The project indicated that external corrosion due to salt environments is not the major cause of the failure of cold end components, but rather that internal corrosion due to the condensate is the most detrimental.

Student Number : 8605435T - MSc research report - School of Construction Economics and Management - Faculty of Engineering and the Built Environment / The purpose of this qualitative research project is to establish whether or not there is currently a property management system or systems available that meet the unique requirements of the overall ICT strategy for the Social Housing sector in South Africa. This included a detailed evaluation of candidate systems wherever possible. A generic functional specification was outlined in the report and these, together with other factors including conformance with the proposed strategic architecture, technology imperatives and vendor characteristics formed the basis of the evaluation and recommendation that followed. The state of Information Technology within a sample group of Housing Instititions was determined, together with an evaluation of available skills. The JD Edwards Financial Real Estate system owned by PeopleSoft and supported by Delloites, stood out as the leading commercial software package to satisfy the requirements of the overall ICT strategy for the sector. The IFCA Property Plus system ranked a close second.

Thesis (M.H.S.H.)--University of Michigan, 1976.

Thesis (M.H.S.H.)--University of Michigan, 1976.

Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2015. / A precise orbit propagator was developed for implementing on a CubeSat's on-board computer for real-time orbital position and velocity determination and prediction. Knowledge of the accurate orbital position and velocity of a Low Earth Orbit (LEO) Cubesat is required for various applications such as antenna and imager pointing. Satellite motion is governed by a number of forces other than Earth's gravity alone. The inclusion of perturbation forces such as Earth's aspheric gravity, third body attraction (e.g. Moon and Sun), atmospheric drag and solar radiation pressure, is subsequently required to improve the accuracy of an orbit propagator. Precise orbit propagation is achieved by numerically integrating a set of coupled second order differential equations derived from satellite's perturbed equations of motion. For the purpose of this study two numerical integrators were selected: RK4 - Fourth order Runge Kutta method and RKF78 - results from embedding RK7 into RK8. The former is a single-step integrator while the latter is a multi-step integrator. These integrators were selected for their stability, high accuracy and computational efficiency. An orbit propagation software tool is presented in this study. Considering the processing power of Central Processing Unit (CPU) of CubeSat's on-board computer and a trade-off between precision and computational cost, the 10 x 10 and 20 x 20 gravity field models, the Exponential atmospheric model and Jacchia 70 static atmospheric model, were implemented. A 60 x 60 gravity field model is also investigated for reference. For validation purpose the developed software tool results were compared with results from Systems Tool Kit (STK) and Satellite Laser Ranging (SLR) using SUNSAT satellite reference orbit. / National Research Foundation

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