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MODELING AND EMBEDDED CONTROL OF AN INFRARED ELECTROMAGNETIC SUSPENSION SYSTEMGustavson, Nathan Zadok 01 December 2011 (has links)
This work describes the modeling, control design, and experimental verification of an electromagnetic suspension system with position feedback using infrared sensors. A nonlinear model is obtained by fitting a first principle analytical model of the system to experimental data. A sliding control strategy is designed using a sliding surface derived from the model to achieve robust stabilization for the closed-loop system. The control is then implemented on an embedded commercial DSP system for experimental verification of the designed control on a laboratory scale electromagnetic suspension system. To compensate for the steady-state tracking error, two modifications are considered. In the first method, a small magnitude integral term is added to the error feedback, equivalently adjusting the reference signal and eliminating the constant bias. In the second method, an integral sliding control is considered, using a higher-order sliding surface, which also eliminates the constant bias. The experimental results show the efficacy of all designed control techniques. The modified techniques, unlike the original design, effectively eliminate the constant position error.
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Instantaneous Project Controls: Current Status, State of the Art, Benefits, and StrategiesJanuary 2016 (has links)
abstract: Despite advancements in construction and construction-related technology, capital project performance deviations, typically overruns, remain endemic within the capital projects industry. Currently, management is generally unaware of the current status of their projects, and thus monitoring and control of projects are not achieved effectively. In an ever-increasing competitive industry landscape, the need to deliver projects within technical, budgetary, and schedule requirements becomes imperative to sustain a healthy return on investment for the project stakeholders. The fact that information lags within the capital projects industry has motivated this research to find practices and solutions that facilitate Instantaneous Project Controls (IPC).
The author hypothesized that there are specific practices that, if properly implemented, can lead to instantaneous controls of capital projects. It is also hypothesized that instantaneous project controls pose benefits to project performance. This research aims to find practices and identify benefits and barriers to achieving a real-time mode of control. To achieve these objectives, several lines of inquiry had to be pursued. A panel of 13 industry professionals and three academics collaborated on this research project. Two surveys were completed to map the current state of project control practices and to identify state-of-the-art or ideal processes. Ten case studies were conducted within and outside of the capital projects industry to identify practices for achieving real-time project controls. Also, statistical analyses were completed on retrospective data for completed capital projects in order to quantify the benefits of IPC. In conclusion, this research presents a framework for implementing IPC across the capital projects industry. The ultimate output from this research is procedures and recommendations that improve project controls processes. / Dissertation/Thesis / Doctoral Dissertation Civil and Environmental Engineering 2016
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Multidisciplinary Optimization for the Design and Control of Uncertain Dynamical SystemsJanuary 2014 (has links)
abstract: This dissertation considers an integrated approach to system design and controller design based on analyzing limits of system performance. Historically, plant design methodologies have not incorporated control relevant considerations. Such an approach could result in a system that might not meet its specifications (or one that requires a complex control architecture to do so). System and controller designers often go through several iterations in order to converge to an acceptable plant and controller design. The focus of this dissertation is on the design and control an air-breathing hypersonic vehicle using such an integrated system-control design framework. The goal is to reduce the number of system-control design iterations (by explicitly incorporate control considerations in the system design process), as well as to influence the guidance/trajectory specifications for the system. Due to the high computational costs associated with obtaining a dynamic model for each plant configuration considered, approximations to the system dynamics are used in the control design process. By formulating the control design problem using bilinear and polynomial matrix inequalities, several common control and system design constraints can be simultaneously incorporated into a vehicle design optimization. Several design problems are examined to illustrate the effectiveness of this approach (and to compare the computational burden of this methodology against more traditional approaches). / Dissertation/Thesis / Ph.D. Electrical Engineering 2014
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Non-vitamin K dependent oral anticoagulants (NOACs) controlsPersson, Anna January 2018 (has links)
In recent years non-vitamin K dependent oral anticoagulants (NOACs) have started to replace warfarin for treatment and prevention of deep venous thrombosis (DVT), pulmonary embolism (PE) and stroke in patients with and without atrial fibrillation. There is a need for a simple and rapid method to detect the presence of these drugs in patient plasma. To meet these new demands, MediRox is developing a screening assay based on a novel prothrombin time (PT) method for rapid detection of NOACs in plasma. The assay is semi-quantitative and by dividing the International Normalised Index (INR) from a NOAC sensitive PT method with the INR from a NOAC insensitive PT method, NOAC containing samples be detected while plasma from normal donors and with warfarin are excluded. The purpose of this project is to develop prototypes of assay quality controls for detection of NOACs in plasma. The results show that the method used for the NOAC control prototypes is applicable and the PT ratio is comparable to patient samples for the low, medium and high concentrations of NOAC. The effect of lyophilisation indicates that the PT ratios for the NOAC control prototypes were nearly unaffected by the lyophilisation. The in-use stability at room temperature (20-25oC) for all NOAC control prototypes were at least 24 hours. The methodology for production needs to be further optimised to increase the commutability to patient samples with very high concentrations of NOAC. The data indicates that the effect of lyophilisation is minimal and the stability of the NOAC control prototypes are satisfying, which is promising for future product development of NOAC controls.
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The Effect of Corporate Social Responsibility Investment and Disclosure on Cooperation in Business CollaborationsFarrington, Sukari 11 November 2017 (has links)
I experimentally examine whether disclosure of corporate social responsibility (CSR) investment facilitates cooperation in business collaborations. Business collaborations are essential for firms to maintain their competitive advantage. However, half of all ventures fail. A major reason for this high failure rate is a lack of cooperation among business collaboration partners, known as relational risk. Findings suggest that CSR disclosure leads to greater CSR investment, but does not result in an overall higher level of cooperation. However, CSR disclosure moderates the link between CSR investment and cooperation. When CSR investment is disclosed, cooperation is highest when both managers invest in CSR. Further, managers who invest in CSR are more sensitive to CSR disclosure information than managers who do not invest in CSR. Managers who invest in CSR are more cooperative when they receive a signal their partner also invested in CSR. Managers who do not invest in CSR do not attend to CSR disclosure information and are equally cooperative when partnered with a CSR investor or a non-CSR investor. Finally, when CSR investment is not disclosed, managers who invest in CSR are no more likely to cooperate than managers who do not invest in CSR. Although CSR is widespread, little is known about why managers invest in CSR or disclose CSR information. This study has implications for practitioners and academics on CSR by demonstrating a potential benefit of CSR investment and disclosure, mitigating relational risk in business collaborations.
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Structural geological controls on the flow and occurrence of groundwater in the basement lithologies of the Limpopo Province, South AfricaPetzer, Konstant Johannes 29 November 2009 (has links)
The work for this thesis was conducted on the basement lithologies of the Limpopo Province in South Africa. An investigation into the correlation between structural geology and the flow/occurrence of groundwater was conducted on these lithologies. Field measurements of geological structures were recorded and compared graphically and statistically to existing groundwater borehole data. Data analysis revealed that the structural geology in the basement lithologies of the Limpopo Province of South-Africa does not have a clearly identifiable influence in terms of spatial patterns in groundwater flow and occurrence at a regional scale. Groundwater targets created through weathering rather than tectonics were evidently more easily recognized. Structural controls on groundwater in the granitic aquifers from this specific area are not totally negligible, although it is believed that such influences will be better identified through intensive local scale investigations. As drilling for groundwater is an expensive practice, the knowledge gained through this study and the possibility of a correlation between groundwater flow/occurrence compared to structural geology might improve the odds of finding groundwater for the communities and farmers in the area. / Dissertation (MSc)--University of Pretoria, 2009. / Geology / unrestricted
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Using vehicle activated signs as an integrated measure to improve road safety in South AfricaSwanepoel, Charl January 2015 (has links)
Road safety is an aspect of major concern on road networks, not only on a local scale in South Africa, but also on a global scale. South Africa is experiencing an unacceptably high rate of fatal road traffic crashes and as a result has one of the highest per capita rate of road fatalities in the world. The Global Plan for the Decade of Action for Road Safety 2011 – 2020 was published in 2011 by the World Health Organisation (WHO) to guide and assist countries with the improvement of road safety. The management of vehicle speeds is one of numerous important interventions identified in the Global Plan. The technical and economic feasibility of using a specific Road safety is an aspect of major concern on road networks, not only on a local scale in South Africa, but also on a global scale. South Africa is experiencing an unacceptably high rate of fatal road traffic crashes and as a result has one of the highest per capita rate of road fatalities in the world. The Global Plan for the Decade of Action for Road Safety 2011 – 2020 was published in 2011 by the World Health Organisation (WHO) to guide and assist countries with the improvement of road safety. The management of vehicle speeds is one of numerous important interventions identified in the Global Plan. The technical and economic feasibility of using a specific technology, namely Vehicle Activated Signs (VAS), to contribute to the overall improvement of road safety on a national level in South Africa were investigated, with particular emphasis on the improvement of road safety through the reduction of fatal road traffic crashes. VAS are part of a range of measures that can be used to curb vehicle speeds, similar to conventional measures like speed cameras and traffic calming devices. VAS technology has seen limited use in South extrapolation of results from SCC’s VAS effectiveness study, and the application of these results to the South African road safety and road user statistics for the one year period March 2011 to March 2012. Key factors relating to speed and general driver obedience were also taken into consideration. It was established that the use of VAS would lead to a moderate reduction in the number of fatal road traffic crashes that occur annually, which in turn holds financial and socio-economic benefits for South Africa. A comparison of selected products available from two South African based electronic road sign manufacturing companies with conventional VAS was also carried out, focussing on product function, use and cost. It has been concluded that it would be technically and economically feasible to introduce VAS on the South African road network to improve the prevailing road safety situation.
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Applying the Draft Articles on the Responsibility of International Organizations: Making International Organizations AccountableLeung, Valerie January 2016 (has links)
The primary aim of this research is to investigate whether the Draft Articles on the Responsibility of International Organizations (ARIO) which were completed in 2011 are an effective means of making IOs accountable for international wrongdoing.
In order to determine this a hypothetical case was created based on the imaginary scenario that the IMF required its member states to eliminate capital controls as a condition for obtaining loans from the organization.
This hypothetical case is argued on behalf of the borrowing states and thus the thesis in part has the form of a legal pleading. This approach was deliberately taken in order to provide a practical example of how the ARIO could be applied to any case related to the responsibility of IOs, not just the one under consideration here. The case is first used to illustrate how the ARIO might be applied in order to determine whether an IO’s conduct amounts to international wrongdoing and results in international responsibility. Secondly, the case is employed to demonstrate whether the ARIO provide remedies for parties injured as a result of international wrongdoing committed by IOs thereby bringing the latter to accountability.
At the end of the investigation it is apparent that conduct such as the IMF’s fictional conduct in relation to its policy would amount to international wrongdoing by an IO in light of the ARIO and would incur international responsibility. However, in the course of applying the ARIO to this fictional case, it becomes evident that although the ARIO are effective for establishing the international responsibility of IOs, they are ineffective as a means of making them accountable for any responsibility they incur because they provide various escapes from the legal consequences for international responsibility. It is therefore concluded that IOs are free to continue to engage in international wrongdoing with impunity despite the creation of the ARIO.
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Aplikace SOX v IBM Česká republika / Aplication of SOX in IBM Czech republicKušnírová, Barbora January 2008 (has links)
This paper is about Sarbanes-Oxley Act that was passed in response to the financial scandals such as Enron and WorldCom. SOX created organization PCAOB that has 6 auditing standards in its portfolio. My thesis is aim at Auditing standard no. 5. IBM was also affected by this law and so the thesis is focused on internal controls, testing and quarterly certification. At the end, there is a part about the relationship between IBM and its customers who are under this law as well.
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Implementace SOX / SOX ImplementationKučerová, Lucie January 2008 (has links)
The thesis deals with the Sarbanes -- Oxley Act of 2002 (SOX). Reasons leading to its acceptance and the consequences are analysed. The costs and benefits of SOX implementation are compared from the individual and global view. The process of implementation is explained on the example of purchasing and account payable.
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