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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.
381

The nuclear matrix affects SATB1-mediated MMTV suppression

Seo, Jin 28 August 2008 (has links)
Not available / text
382

Small power, three to one phase matrix converter for wind generators

Nicolae, DV, Richards, CG, Ehlers, P 10 April 2010 (has links)
Abstract- This paper will investigate the use of a three-to-one Matrix converter to synchronize the electrical energy and condition the output of the wind generator. A Matrix converter is a direct ACAC solution, removing the need for large smoothing capacitors in a typical rectifier/inverter solution. This paper will briefly review the Matrix converter operational theory. A simulation and the practical results of a three-to-one phase matrix converter for varying input frequencies are also presented. The conclusion shows that the proposal is a viable solution for small power wind harvesting.
383

Motivating potential of performance management systems in matrix organizations

Fernandez, Gabriela, 1981- 18 February 2011 (has links)
The main purpose of this report is to identify and describe the type of behaviors that should be promoted in a matrix organization. This report shows how the performance management system is a very important tool in promoting these behaviors. The report starts with an introduction to the relationship between the success of a matrix structure and the appropriate performance management system followed by the definition of important concepts in this topic. Next, the report provides general recommendations to the leaders of matrix organizations with respect their performance management system. Finally, a case study of a company with this type of structure is analyzed. / text
384

The dynamic stiffness method

周婉娥, Zhou, Wan-E. January 1996 (has links)
published_or_final_version / Civil and Structural Engineering / Doctoral / Doctor of Philosophy
385

Mechanism of action of silicon : extracellular matrix synthesis and stabilisation

Kopanska, Katarzyna January 2012 (has links)
No description available.
386

Mueller matrix imaging for skin cancer detection

Baldwin, Angela Michelle 30 September 2004 (has links)
Over one million Americans are afflicted with skin cancer each year. Even though skin cancer has a 95% cure rate, approximately 10,000 people die in the United States each year of this disease. The current ABCDE(F) detection method is not sensitive enough to detect skin cancer in its early stages and requires a biopsy for any suspicious lesions. A lot of unnecessary biopsies, which are painful and costly to the patient, are taken. Therefore, a noninvasive technique is needed that can accurately detect the presence of skin cancer. In this thesis, an optical approach will be presented that has potential to be a noninvasive skin cancer detection technique. Several morphological and biochemical changes occur as tissue becomes cancerous, and therefore the optical properties of the tissue can be used to detect skin cancer. A Mueller matrix imaging system has been developed by our group that measures the 16 or 36-element Mueller matrix, which completely describes the optical properties of the tissue sample. The system is automated and can collect the Mueller matrix in less than one minute. This system will be used to image Sinclair swine, and data analysis techniques will be employed to determine if the system can distinguish between cancerous and noncancerous tissue. System software improvements will also be made, and a new calibration technique will be presented.
387

Riccati Equations in Optimal Control Theory

Bellon, James 21 April 2008 (has links)
It is often desired to have control over a process or a physical system, to cause it to behave optimally. Optimal control theory deals with analyzing and finding solutions for optimal control for a system that can be represented by a set of differential equations. This thesis examines such a system in the form of a set of matrix differential equations known as a continuous linear time-invariant system. Conditions on the system, such as linearity, allow one to find an explicit closed form finite solution that can be more efficiently computed compared to other known types of solutions. This is done by optimizing a quadratic cost function. The optimization leads to solving a Riccati equation. Conditions are discussed for which solutions are possible. In particular, we will obtain a solution for a stable and controllable system. Numerical examples are given for a simple system with 2x2 matrix coefficients.
388

Amicable T-matrices and applications

Gholamiangonabadi, Hamed January 2012 (has links)
Our main aim in this thesis is to produce new T-matrices from the set of existing T-matrices. In Theorem 4.3 a multiplication method is introduced to generate new T-matrices of order st, provided that there are some specially structured T-matrices of orders s and t. A class of properly amicable and double disjoint T-matrices are introduced. A number of properly amicable T-matrices are constructed which includes 2, 3, 5, 6, 7, 9, 10, 11, 13, 14, 18, 22. To keep the new matrices disjoint an extra condition is imposed on one set of T-matrices and named double disjoint T-matrices. It is shown that there are some T-matrices that are both double disjoint and properly amicable. Using these matrices an infinite family of new T-matrices are constructed. We then turn our attention to the application of T-matrices to construct orthogonal designs and complex Hadamard matrices. Using T-matrices some orthogonal designs constructed from 16 circulant matrices are constructed. It is known that having T-matrices of order t and orthogonal designs constructible from 16 circulant matrices lead to an infinite family of orthogonal designs. Using amicable T-matrices some complex Hadamard matrices are shown to exist. / iii, 49 leaves ; 29 cm
389

Chemical Additive Selection in Matrix Acidizing

Weidner, Jason 1981- 16 December 2013 (has links)
This work proposes to survey new chemical knowledge, developed since 1984, on fluid additives used in matrix stimulation treatments of carbonate and sandstone petroleum reservoirs and describes one method of organizing this new knowledge in a software program using the Visual Basic for Applications programming language. While matrix stimulation treatments have been used in the petroleum industry for over 100 years, the last major review of the technical literature addressing this process occurred in 1984. Currently though, the petroleum industry better understands formation damage; uses different and more chemical additives in matrix stimulation treatments; and understands how some additives interact with one another affecting well performance. As a result, a new and thorough review of the literature regarding chemical additive choices for matrix stimulation treatments will help practicing engineers achieve better results worldwide. Moreover, organizing this chemical knowledge in a software program using VBA allows an engineer to access the information through Microsoft's widely available spreadsheet program, Microsoft Excel.
390

Formation Damage Due to Iron Precipitation during Matrix Acidizing Treatments of Carbonate Reservoirs and Ways to Minimize it Using Chelating Agents

Assem, Ahmed I 16 December 2013 (has links)
Iron precipitation during matrix acidizing treatments is a well-known problem. During matrix acidizing, successful iron control can be critical to the success of the treatment. Extensive literature review highlighted that no systematic study was conducted to determine where this iron precipitates, the factors that affect this precipitation, and the magnitude of the resulting damage. Iron (III) precipitation occurs when acids are spent and the pH rises above 1, which can cause severe formation damage. Chelating agents are used during these treatments to minimize iron precipitation. Disadvantages of currently used chelating agents include limited solubility in strong acids, low thermal stability, and/or poor biodegradability. In this study, different factors affecting iron precipitation in Indiana limestone rocks were examined. Two chelating agents, GLDA and HEDTA, were tested at different conditions to assess their iron control ability. Results show that a significant amount of iron precipitated, producing a minimal or no gain in the final permeability, this indicated severe formation damage. The damage increased with the increase of the amount of iron in solution. When chelating agents were used, the amount of iron recovered depended on both chelate-to-iron mole ratio and the initial permeability of the cores. Calcium is chelated along with iron, which limits the effectiveness of chelating agents to control iron (III) precipitation. Acid solutions should be designed considering this important finding for more successful treatments.

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