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Linear equivalents of nonlinear systemsTse, Wilfred See Foon January 1987 (has links)
Consider the following nonlinear system
[Formula Omitted]
where ϰ ∈ Rⁿ, f, ℊ₁,…,ℊm are C∞ function in Rⁿ and ℎ is a C∞ function in R⍴, all defined on a neighborhood of 0. The problem of finding a necessary and sufficient condition such that system (1) can be transformed to a linear controllable system by a state coordinate change and feedback has been studied
quite well. In this thesis, we first discuss a few different approaches to this problem and eventually we will show that the slightly different versions of the necessary and sufficient condition discovered are equivalent. Next we consider
system (1) with all սi,= 0 together with system (2), and study the dual problem of transforming it to a linear observable system by a state and output coordinate change. Finally, we consider briefly system (l) and (2) with nonzero սi and study the problem of transforming it to a linear system that is both completely controllable and observable. Examples are given and applications to local stabilization and estimation are discussed. / Science, Faculty of / Mathematics, Department of / Graduate
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Subjective odor measurement for the evaluation of agricultural odor control methodsPhillips, David Alexander January 1979 (has links)
Odor measurement is a useful tool in the evaluation of agricultural odor control methods. Subjective odor measurement
techniques utilizing man's sense of smell as an analytical instrument are discussed. The use of these methods ineevaluating agricultural odor control systems is also reviewed.
A dynamic dilution to threshold odor measurement method is used to evaluate odorous air samples collected downwind from an on farm agitated basin containing anaerobic liquid swine manure. Samples were collected from the time of agitator startup. It is found that short term surface aeration of anaerobic liquid swine manure reduces the threshold of the odorous gases being emitted by at least two orders of magnitude.
It is shown that odor samples with a 'high odor level' in Tedlar (Polyvinyl Flouride Plastic) bags can be stored for 48 hours before threshold analysis without a significant change occurring in the odor threshold.
It is found that odor samples with a 'low odor level'* collected in Tedlar bags have a likely storage life of at least 24 hours.
* High odor lever is defined here as 5,000 to 10,000 dilutions to threshold.
** Low odor level is defined here as less than 500 dilutions to threshold. / Land and Food Systems, Faculty of / Graduate
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Sufficient conditions for optimal control and the generalized problem of BolzaZeidan, Vera Michel January 1982 (has links)
We develop in this thesis four sufficiency criteria for the generalized problem of Bolza. These results represent a unification, in the sense that they can be applied to both the calculus of variations and to optimal control problems, as well as to problems with nonsmooth data.
The first criterion, "point convexity", extends the convexity approach of Rockafellar. However, we derive a "Hamiltonian-Jacobi" approach which can be applied when the point convexity assumption fails to be satisfied. The method employed for this criterion brings to light a new point of view concerning the Jacobi condition in the classical calculus of variations. The latter can be considered as a condition which guarantees the existence of a canonical transformation transforming the original Hamiltonian to a locally concave-convex Hamiltonian. The third sufficiency criterion is an extension of the Hamilton-Jacobi approach from optimal control to the generalized problem of Bolza. This result gives rise to another sufficiency criterion in terms of a certain inequality.
Our theorems on sufficient conditions are closely related. We prove that under certain assumptions the last three approaches can be unified. By this we mean that their hypotheses are equivalent. However, the point convexity, and hence the convexity, criterion turns out to have the most restrictive hypotheses of the four.
The generality of the theorems proven stems to a great extent from the fact that not only non-differentiable but even infinite-
valued functions are allowed in the treatment. The utility of using such functions appears when we apply these theorems to optimal control problems. / Science, Faculty of / Mathematics, Department of / Graduate
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The integration of quality management and the competitiveness of PG Bison manufacturingAlly, Feizel 22 May 2008 (has links)
Fundamentally quality is the goal for every organization to achieve excellence. Quality management is much broader than the organization. These days quality incorporates government legislation and pressures from international communities concerned with protecting the environment and people health & safety. Quality is not just product acceptance by customers. It penetrates through the functional divisions of the organization to integrate product reliability, environment protection and people health & safety. Quality management is a business strategy that can jointly promote an organization and the products and services they offer. The Integration of Quality Management and the Competitiveness of PG Bison Manufacturing is a business strategy that encompasses a combination of product brands, product application, environment protection, health & safety and lead times to create an awareness of the effect quality will have on the entire business. Adopting and embracing the quality philosophies and some of the models proposed by American and Japanese quality experts will revitalize business excellence. The pressures of the external environment cannot be ignored when incorporating quality in a business. Political, economic, social and technology factors influence the quality progress of an organization. Concerns of fluctuating exchange rates, inflating fuel prices, imports, HIV and AIDS that influence the GDP and CPIX are important considerations of quality management within an organization. Knowledge of the environment should include the social enlistment of people where their basic needs are seen to by government’s social programs. The political spectrum that impact on organizations is sanctions imposed on a country or promoting a country by awarding sports events like the 2010 soccer world cup to be hosted in South Africa. The findings of this research indicate that customers are willing to support PG Bison in their endeavors to protect the environment and to promote health & safety. Many customers are unaware of the product application support PG Bison offer thereby using toxic adhesives for product applications. The importance of product branding was demonstrated by customer responses whereby they indicated that the product brands Formica, Deccon and Melawood are premier brands. However the brands are not well expressed in the market. Some market share could be lost due to the lack of branding. Many customers are dissatisfied with the 11-15 days lead times they are quoted for some of the products. They point out that they would purchase competitor products or they would look for an alternative product if the lead times were too long. The Integration of Quality Management and the Competitiveness of PG Bison Manufacturing stimulated meaningful manufacturing and warehouse process improvements including better storage and packaging systems to promote the health & safety of people and environment protection. Integrating quality management will enhance business performance and will make organizations competitive globally. Some of the models identified can be incorporated in any organization to promote the forthcoming ISO standards and to improve business performance in marketing, operations, distribution and other functional departments. The study proved successful in that PG Bison’s cost savings will escalate while the proposed structures in manufacturing and warehousing will be better organized than before. / Dr. A. Stephanou
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A diffusion model for a two product inventory systemLing, Daymond January 1978 (has links)
This thesis presents the results of an investigation of a continuous-time two product inventory model in which the stock level of two divisible commodities is represented by a two dimensional diffusion process. Two classes of replenishment policies are considered. One is a two dimensional analog of the stationary one dimensional (s,S) policy; i.e., when either the inventory of product one declines to s₁ or when the inventory of product two declines to s₂, both stocks are instantaneously replenished, product one up to S₁, and product two up to S₂. This is referred to as the (s₁,s₂,S₁,S₂) policy. The inventory is then allowed to decline again and is replenished. These cycles continue indefinitely. There are costs associated with the replenishment of stock and maintaining a given inventory. The objective is to choose values for (s₁,s₂,S₁,S₂,) to minimize the long-run average cost of opirating such a system. The appropriate theory of diffusion processes is heuristically developed and then applied to evaluate this cost. In general, analytic solutions cannot be obtained., Classical numerical analysis methods are used to obtain the average costs for given (s₁,s₂,S₁,S₂) values and to select the best such values. One dimensional diffusion models are a special case of the present model and Puterman's [21] results are used to verify the results obtained. The other policy examined differs from the two dimensional (s₁,s₂,S₁,S₂) policy in that the lower levels, s₁ and s₂, of the stock levels are coupled in the form of an elliptic arc. Numerical solution of this policy can be obtained and comparisons of the two policies are made. / Business, Sauder School of / Operations and Logistics (OPLOG), Division of / Graduate
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Propuesta de mejora en la gestión de inventarios para el almacén de insumos en una empresa de consumo masivoCalderón Pacheco, Anahís Shirley 01 July 2014 (has links)
Tesis
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A comparison of the Inverse Nyquist Array and Pole Assignment techniquesVenzke, Rainer Horst Erich January 1989 (has links)
Bibliography: pages 171-173. / This dissertation compares the Inverse Nyquist Array (INA) and the Pole Assignment techniques in multivariable control system design. The representation of multivariable systems in both the frequency domain and state space is discussed. A laboratory flotation system, for which a model by step response analysis is derived, is used as a practical example for both methods. A detailed description of the theory of both techniques is given. Particular emphasis is given to how the theory can be applied with the use of a personal computer. Computer-aided control system design programs for the INA and Pole Assignment techniques are included. A complete feedback control scheme for the flotation rig is designed with the INA technique. Pole Assignment by state feedback is used to improve the speed of response of the rig. The implementation of a Kalman filter, which is required for the Pole Assigment technique, is also described.
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Online data-driven control of safety-critical systemsCohen, Max H. 30 May 2023 (has links)
The rising levels of autonomy exhibited by complex cyber-physical systems have brought questions related to safety and adaptation to the forefront of the minds of controls and robotics engineers. Often, such autonomous systems are deemed to be safety-critical in the sense that failures during operation could significantly harm the system itself, other autonomous systems, or, in the worst-case, humans interacting with such a system. Complicating the design of control and decision-making algorithms for safety-critical systems is that they must cope with various degrees of uncertainty as they are deployed autonomously in increasingly real-world environments. These challenges motivate the use of learning-based techniques that can adapt to such uncertainties while adhering to safety-critical constraints.
The main objective of this dissertation is to present a unified framework for the design of controllers that learn from data online with formal guarantees of safety. Rather than using a controller trained on an a priori dataset collected offline that is then statically deployed on a system, we are interested in using real-time data to continuously update the control policy online and cope with uncertainties that are challenging to characterize until deployment. We approach the problem of designing such learning-based control algorithms for safety-critical systems through the use of certificate functions, such as Control Lyapunov Functions (CLFs) and Control Barrier Functions (CBFs), from nonlinear control theory. To this end, we first discuss how modern data-driven techniques can be integrated into traditional adaptive control frameworks to develop classes of CLFs and CBFs that facilitate the design of both controllers and learning algorithms that guarantee, respectively, stability and safety by construction. Next, we shift from the problem of safe adaptive control to safe reinforcement learning where we demonstrate how similar ideas from adaptive control can be extended to safely learn the value functions of optimal control problems online using data from a single trajectory. Finally, we discuss an extension of the aforementioned approaches to richer control specifications given in the form of temporal logic formulas, which provide a formal way to express complex control objectives beyond that of stability and safety. / 2025-05-30T00:00:00Z
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Evaluation of Rescue Applications on Glyphosate-Resistant Palmer AmaranthDenton, Andrew Boyette 12 August 2016 (has links)
Options for glyphosate-resistant (GR) Palmer amaranth [Amaranthus palmeri (S. Wats)] control are becoming limited. Research was conducted in 2014 and 2015 to evaluate the effectiveness of rescue herbicide applications on glyphosate-resistant Palmer amaranth. Research was established to evaluate efficacy provided by new and current herbicide programs on GR Palmer amaranth that was larger than recommended at the time of herbicide application. Studies included a postemergence application of different herbicides used singly and in combination at different initial application timings; sequential postemergence application timing evaluating herbicide tank mix combinations at five different time intervals between applications; and postemergence evaluation of herbicide tank mix combinations at multiple application timings.
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Some results on the performance bounds in minimum variance controlChen, Ming-Jeh. January 1978 (has links)
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