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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Early Stages Of Calcareous Soil Reclamation Along The TMX-Anchor Loop Pipeline In Jasper National Park

Cartier, Sarah B. 11 1900 (has links)
Research assessed early stages of calcareous soil reclamation along the TMX-Anchor Loop pipeline through Jasper National Park. Calcareous soils are low in nutrients and highly prone to erosion after disturbances. Four sites were established in each of five calcareous soils, and divided into three pipeline right-of-way areas; work, trench and spoil. Ten amendment treatments, established within each right-of-way areaincluded a control and combinations of wood chips, fertilizer and compost with some plots having amendments incorporated. Wood chip treatments decreased availability of soil nutrients, with small plants contributing to high vegetation densities and low cover. Compost treatments increased soil nutrients and aided large plant establishment, creating lower plant densities and higher cover. Light application rates were most successful, with higher native plant densities and cover in relation to heavy application rates, which encouraged robust non-native plants. Pipeline right-of-way areas had no overall impact on early reclamation success. / Land Reclamation and Remediation
102

Control loop performance assessment with closed-loop subspace identification

Danesh Pour, Nima 11 1900 (has links)
This thesis is concerned with subspace identification and its applications for controller performance assessment and process modeling from closed-loop data. A joint input-output closed-loop subspace identification method is developed which provides consistent estimation of the subspace matrices and the noise covariance matrix required for the LQG benchmark curve estimation. Subspace LQG benchmark is also used for performance assessment of the cascade supervisory-regulatory control systems. Three possible scenarios for LQG control design and performance improvement are discussed for this structure. A closed-loop subspace identification method is also provided for estimation of the subspace matrices necessary for performance assessment. A method of direct step model estimation from closed-loop data is provided using subspace identification. The variance calculation required for this purpose can be performed using the proposed method. The variances are used for weighted averaging on the estimated Markov parameters to attenuate the noise influence on the final step response estimation. / Process Control
103

Simulation and development of a mock circulation loop with variable compliance

Gregory, Shaun David January 2009 (has links)
Heart disease is attributed as the highest cause of death in the world. Although this could be alleviated by heart transplantation, there is a chronic shortage of donor hearts and so mechanical solutions are being considered. Currently, many Ventricular Assist Devices (VADs) are being developed worldwide in an effort to increase life expectancy and quality of life for end stage heart failure patients. Current pre-clinical testing methods for VADs involve laboratory testing using Mock Circulation Loops (MCLs), and in vivo testing in animal models. The research and development of highly accurate MCLs is vital to the continuous improvement of VAD performance. The first objective of this study was to develop and validate a mathematical model of a MCL. This model could then be used in the design and construction of a variable compliance chamber to improve the performance of an existing MCL as well as form the basis for a new miniaturised MCL. An extensive review of literature was carried out on MCLs and mathematical modelling of their function. A mathematical model of a MCL was then created in the MATLAB/SIMULINK environment. This model included variable features such as resistance, fluid inertia and volumes (resulting from the pipe lengths and diameters); compliance of Windkessel chambers, atria and ventricles; density of both fluid and compressed air applied to the system; gravitational effects on vertical columns of fluid; and accurately modelled actuators controlling the ventricle contraction. This model was then validated using the physical properties and pressure and flow traces produced from a previously developed MCL. A variable compliance chamber was designed to reproduce parameters determined by the mathematical model. The function of the variability was achieved by controlling the transmural pressure across a diaphragm to alter the compliance of the system. An initial prototype was tested in a previously developed MCL, and a variable level of arterial compliance was successfully produced; however, the complete range of compliance values required for accurate physiological representation was not able to be produced with this initial design. The mathematical model was then used to design a smaller physical mock circulation loop, with the tubing sizes adjusted to produce accurate pressure and flow traces whilst having an appropriate frequency response characteristic. The development of the mathematical model greatly assisted the general design of an in vitro cardiovascular device test rig, while the variable compliance chamber allowed simple and real-time manipulation of MCL compliance to allow accurate transition between a variety of physiological conditions. The newly developed MCL produced an accurate design of a mechanical representation of the human circulatory system for in vitro cardiovascular device testing and education purposes. The continued improvement of VAD test rigs is essential if VAD design is to improve, and hence improve quality of life and life expectancy for heart failure patients.
104

Cloning and characterisation of gripe, a novel interacting partner of e12 during brain development

Heng, Julian Ik Tsen Unknown Date (has links)
The mammalian cerebral cortex is a remarkable product of brain evolution, and is the structure that most distinctively delineates the human species from others (Northcutt and Kaas, 1995; Rakic, 1988). Neurons in the adult brain are organised into cytoarchitectonic areas, defined by distinct biochemical, morphological and physiological characteristics (Rakic 1988). Remarkably, this complex structure is generated from a simple neuroepithelium. (For complete abstract open document)
105

Echtzeitsimulation von Produktionsanlagen mit realen Steuerungselementen /

Röck, Sascha. January 2007 (has links)
Universiẗat, Diss.--Stuttgart, 2007.
106

Heuristic optimization methods for the characterization of dynamic mechanical properties of composite materials

Hornig, Klaus H. Flowers, George T. January 2007 (has links) (PDF)
Dissertation (Ph.D.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references.
107

Oncogenic function of TWIST in the development and progression of prostate cancer

Kwok, Wai-kei. January 2007 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.
108

Entwicklung eines Bewertungsverfahrens zum Vergleich von Lenkungen in Kundenhand hinsichtlich Kraftstoffverbrauch

Wenzel, Pauline Hildegard Elisabeth January 2008 (has links)
Zugl.: München, Techn. Univ., Diss., 2008
109

Echtzeitfähige Modellierung des dieselmotorischen Verbrennungsprozesses /

Merz, Benedikt. January 2008 (has links)
Zugl.: Karlsruhe, Universiẗat, Diss., 2008.
110

Re-humanizing the commercial core a masterplan for Chicago's Central Loop /

Hoyt, Neil E. January 2005 (has links)
Thesis (M. Arch. D.U.)--University of Notre Dame, 2005. / Thesis directed by Richard Economakis for the School of Architecture. "April 2005." Includes bibliographical references (leaves 95-97).

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