This thesis explores different paradigms for incorporating uncertainty with optimization frameworks for applications in chemical engineering and site-wide operations. First, we address the simulation optimization problem, which deals with the search for optimal input parameters to black-box stochastic simulations which are potentially expensive to evaluate. We include a comprehensive literature survey of the state-of-the-art in the area, propose a new provably convergent trust region-based algorithm, and discuss implementation details along with extensive computational experience, including examples for chemical engineering applications. Next, we look at the problem of long-term site-wide maintenance turnaround planning. Turnarounds involve the disruption of production for significant periods of time, and may incur enormous costs in terms of maintenance manpower as well as lost sales. The problem involves (1) the simulation of profit deterioration due to wear and tear followed by the determination of how frequently a particular turnaround should take place; and (2) the consideration of site network structure and turnaround frequencies to determine how turnarounds of different plants may be coordinated over a long-term horizon. We investigate two mixed-integer models, the first of which determines optimal frequencies of individual plant turnarounds, while the second considers maximizing long-term profit through coordination of turnarounds across the site. We then turn to more conventional methods of dealing with optimization under uncertainty, and make use of a combined robust optimization and stochastic programming approach to medium-term maintenance planning in integrated chemical sites. The nature of the uncertainty considered affects two aspects of maintenance planning, one of which is most suitably addressed through a robust optimization framework, while the other is better handled with stochastic programming models. In summary, we highlight the importance of considering uncertainty in optimization as well as the choice of approach or paradigm used through chemical engineering applications that span varied domains and time scales.

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It is the purpose of this study to (1) produce a play in an expressionistic style; (2) submit a thesis of analysis; and (3) present the thesis in such a way as to show that an expressionistic style can be applied to a play written for the professional stage in a creative, artistic manner.

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Magister Public Health - MPH / Background: Malnutrition is a complex condition profoundly impacting child mortality and morbidity, especially in sub-Saharan Africa. Severe acute malnutrition is of growing concern locally where unacceptable mortality rates persist, despite reasonable standards of clinical care. Aim: To determine factors associated with morbidity and mortality in children under-five years admitted with severe acute malnutrition to a regional paediatric hospital in KwaZulu-Natal. Methodology: This was a quantitative study. A retrospective observational study design was used. Medical records of all children with severe acute malnutrition, under the age of five years, admitted between April 2015 and December 2016 to the regional paediatric hospital in KwaZulu-Natal were included. Data was obtained from medical records and admission books. A trained research assistant was used to extract and record data with a piloted data extraction tool. Data was entered and cleaned using Microsoft Excel and analysed using SPSS (v 20) and STATA (v 14). Descriptive summary statistics were used to describe the characteristics of the study population and bivariate analysis using t-tests and Chi-square tests to determine significance. Kaplan Meier and Multivariate Cox regression was used to assess the association of variables with morbidity and mortality. Results: Of the 276 eligible case records included in the study, 54% were male and 90% of all cases were younger than 2 years. Even though associations did not reach significance, teenage pregnancy and unemployment was high amongst the caregivers of the study population. Most of the malnourished children admitted (74%) presented with multiple comorbidities. Diarrhoea (43%), HIV- infection (30%) and respiratory tract infections (30%) were the top three comorbidities found, followed by tuberculosis (27%). The overall mortality rate was 8.7%. Survival probability was significantly reduced in children with pneumonia and those who presented with hypoglycaemia, dehydration, dermatosis, severe pallor, altered consciousness or shock on admission (p < 0.05). There was a significantly increased risk of death in males (HR = 0.174, 95%CI = 0.05 - 0.665), and in those who presented with dehydration (HR = 4.1, 95%CI = 1.25 - 13.59), evidence of lethargy or coma (HR = 4.2, 95%CI = 1.04 - 17.12) or multiple clinical signs (HR = 4.4, 95% CI =2.56 - 7.59) on admission (p < 0.05). The comorbidities HIV-infection (HR = 9.9, 95%CI = 1.39 - 70.68) and pneumonia (HR = 3.4, 95%CI = 1.56 - 7.43) showed a significantly increased mortality risk (p < 0.05). Conclusion: This study supports the body of evidence that despite reasonable standards of hospital care, it is difficult to obtain the target for severe acute malnutrition mortality (< 5%), likely due to the presence of contextually specific factors. Local interventions at hospital, primary health care and community level is needed, as well as further research to facilitate comprehensive policy-making.

A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Cancer‐related fatigue (CRF) is a well‐documented symptom among gynecologic oncology patients. However, there is little known about the etiology, and treatment options are currently suboptimal. While the lack of knowledge surrounding the intricacies of CRF impedes effective care, there is arguably a more serious barrier to delivering adequate treatment. Fatigue symptoms are highly underreported to physicians making it impossible to offer treatment to a large subsection of patients. This study will focus specifically on gynecologic oncology patients, a population with a staggering prevalence of CRF. The purpose of this study is to identify clinical, psychosocial, and lifestyle characteristics that may be associated with the underreporting of fatigue specifically in gynecologic oncology patients. The design of this study is a cross‐sectional survey. 89 subjects were recruited from three outpatient sites. Inclusion criteria included: (a) women age ≥18 years old with a known ovarian, uterine, cervical, vaginal, vulvar, or primary peritoneal cancer; (b) Currently attending physician’s office hours and/or undergoing chemotherapy at one of the above listed centers. This study will focus specifically on the reporting of CRF in gynecologic oncology patients. Results showed that barriers to reporting fatigue were significantly correlated with the chemotherapy cycle a patient was undergoing. Additionally, the date of last treatment, a patient’s weight, and the cancer stage was associated with higher levels of underreporting in this population. The prevalence of cancer related fatigue is staggering; however, there is limited research as to why patients are underreporting such a significant symptom to their health care team. With the knowledge from this study, screening for fatigue can become more efficient by targeting women in specific chemotherapy cycles. Practitioners can also use this data to identify patients with high‐risk characteristics that might contribute to their unwillingness to discuss fatigue symptoms.

Some studies have shown that managers concentrate large fractions of their wealth in the equity of their own firm. In this paper we use a unique dataset and investigate how Swedish owner-managers invest remaining wealth conditional on a major investment in their own firm. We find no[JR1] evidence that owner-managers seek diversification benefits when they invest remaining wealth. Instead some owner-managers invest remaining wealth in the industry where they already have a substantial capital investment. We conclude that some owner-managers seek to exploit their industry-specific superior information when they invest wealth not tied up in their own firms. / <p>QC 20130515</p>

Humanoid robots have proven to be very useful and could revolutionize the way humans live. Knowing human anatomy and behaviour helps improve a robotic mechanisms ability to perform human tasks. The following thesis introduces the concept of a threefingered robot hand and its driving mechanism. The hand includes two fingers and a thumb. Using the concept of “an under actuated system”, each finger consists of three revolute joints which are driven by two actuators and tooth belt transmission system. The thumb has two joints but only one joint is active and actuated by one motor. The passive joint is designed to set the initial position of the thumb on the piano key if necessary. Required angle of rotation for each joint has been calculated through Inverse Kinematics. Once the fingertip presses the piano key, it should apply 1N force to play a note. Force Sensing Resistors at each finger tip, as a control method, are introduced to the system to accurately measure the amount of applied force from the finger tip on the key and increase the angle of rotation of the motor if needed. Stress and deformation of the joints have been studied through Finite Element Analysis. A prototype model, consisting of a single finger was built to better understanding the functionality of the concept. Analysis of this model, led to necessary modification of the transmission system and some design revisions to each link. Genetic Algorithm using MATLAB was used to optimize the performance Index of a finger. Finally the hand assembly including all the components and driving mechanism was constructed and experimented in the playing mode. / UOIT

Our task was to create a virtual test bench for verifying memory addresses in our commissioning body’s models. The purpose with the testbench was that it should be created in such a way that it would be easy to change the device under test without any major changes in the testbench. To solve the problem that the testbench had to be able to verify different devices we had to create a general enviroment for how the testbench had to be composed. By doing an analysis of which com-ponents that are usually included in a testbench and which components that were necessary in our project we came up with a generall enviroment for the testbench. Our result was a testbench with the follwing basic functions: * Read from a file that contains read and write operations to the Device Under Test (DUT).* Apply the stimulus to the device* Read the results from the device* Compare the results with wanted values* Generate a log file which contains information about the simulation result.

This research successfully created an ultra-small orifice utilizing undercut fabrication process in a droplet-based microfluidics chip. The proposed novel T-junction structure with ultra-small orifice has a lot of advantages, including long-term stability for uniform droplets formation, reproducible ultra-small size droplet and tunable droplet size. The hydraulic diameter of the orifice is under 2 £gm, and the size of micro droplet produced from the orifice can be tuned to less than 10 £gm in diameter. Chitosan droplet can be produced by the proposed chip, which is usually adopted for medical applications. Surface modification technique was applied to modify the surface of microchannel to be hydrophobic for eaily producing hydro-droplets. Experimental results show that the ultra-small orifice microfluidics chip can steadily produce water-in-oil droplets only by controlling the flow ratio between dispersed phase and continuous phase flow rates. The size of the water-in-oil droplets can be tunable from 22 £gm to 6.5 £gm in diameter by adjusting the flow rate ratio of the continuous and disperse phase flows from 1 to 3.5 and the hydraulic diameter of the orifice is 1.1 £gm. And the size of the chitosan-in-oil droplets also can be tunable from 59 £gm to 27 £gm by adjusting the flow rate ratio of the continuous and disperse phase flows from 4 to 8. The proposed microchip has advantages including ease of control, low cost, and high throughput. The proposed technique can be widely applied on emulsion and micro droplet generation.