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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.
11

Behavior of Diagonal Knee Moment End-Plate Connections

Italiano, Vincenza M. 14 May 2001 (has links)
An experimental and analytical investigation was conducted to study the behavior of diagonal knee moment end-plate connections and a multiple row extended moment end-plate connection. Diagonal knee moment end-plate connections differ from typical moment end-plate connections because of the large pitch distance required between the top flange and first row of tension bolts. The large pitch distance is outside of the geometric parameters of all previous research. Design solutions are presented for five moment end-plate connections with provisions added to accommodate these parameters. The analytical investigation focused on the limit states of end-plate yielding and bolt rupture. Yield-line analysis was used to predicted end-plate yielding and a simplified Kennedy method proposed by Borgsmiller and Murray (1995) was used to predict bolt rupture including and excluding prying forces. An experimental investigation was conducted to verify the design solutions. Five knee area specimens and one plate girder specimen were tested in this study. The analytical and experimental results are analyzed and compared. For the test specimens that failed in the connection, the predicted results proved to be conservative. Recommendations are presented at the end of the study as well as sample calculations. / Master of Science
12

The effect of a random ocean on acoustic intensity fluctuations

Campbell, Gordon January 1994 (has links)
No description available.
13

CP violation in gauge theories and the electric dipole moment of the neutron

Hamzaoui, C. January 1987 (has links)
No description available.
14

Application of moment wavelet transform to quantum mechanics

Ogbazghi, Asmerom Y. 01 July 1998 (has links)
In this work we reconstruct Quantum Mechanical wave functions for some confining potentials, using the moment-wavelet method of Handy and Murenzi. This method consists in transforming the Schrodinger equation into an equivalent continuous wavelet transform (CWT) representation involving scaled and translated moments, µ1/ α,b (p)=∫χpe-Q\( Ψ(x +b), where ϐ -Q becomes the mother wavelet. The discrete bound states are determined through a multiscale process involving the integration of a finite number of coupled linear first order differential equation in the moments µ1/ α,b (p). The underlying initial value problem depends on moment quantization methods to determine the infinite scale (a = ∞) moments and energy. Using this method we calculate the energies and wavefunctions for the first two quantum states of quartic and dectic anharmonic oscillator potentials, V(x) = mχ2 + gχ4, V(χ) = χ 2+χ10 respectively.
15

Orthogonal polynomials and the moment problem

Steere, Henry Roland 01 October 2012 (has links)
The classical moment problem concerns distribution functions on the real line. The central feature is the connection between distribution functions and the moment sequences which they generate via a Stieltjes integral. The solution of the classical moment problem leads to the well known theorem of Favard which connects orthogonal polynomial sequences with distribution functions on the real line. Orthogonal polynomials in their turn arise in the computation of measures via continued fractions and the Nevanlinna parametrisation. In this dissertation classical orthogonal polynomials are investigated rst and their connection with hypergeometric series is exhibited. Results from the moment problem allow the study of a more general class of orthogonal polynomials. q-Hypergeometric series are presented in analogy with the ordinary hypergeometric series and some results on q-Laguerre polynomials are given. Finally recent research will be discussed.
16

THE INTERACTION OF FLEXURE AND COMPRESSION IN REGULAR AND OFFSET EXTERIOR COLUMNS

Joshi, Angela 01 August 2019 (has links)
When a structural element is acted upon by axial compressive force simultaneously with bending, the design must consider the effect of combined bending and compression. Hence, the structure should be designed with the consideration of bending moment in order to provide the enough design strength to the member. The main objective of this thesis is to compare the effect of interaction of flexural moment and axial compressive force on the regular column of the steel moment frame with the same column when cantilever section is introduced into the frame as the loading is kept constant in all three cases. In this work, STAAD is used to determine the required variables such as axial forces, bending moments and deformations in all the cases, and those values are used in approximate second order analysis for the further analysis of special steel moment frame. The calculated values are then plugged into the design interaction equation for combined flexure and compression as given by AISC Steel Construction Manual (2011) to check the criticality of the moment frame. The result of the analysis indicates that the regular frame model has higher demand of capacity ratio in design of columns than the one with cantilever projection.
17

Contributions to the search for a neutron EDM

Miranda, P. M. C. January 1987 (has links)
The work described in this thesis was carried out at the Institut Laue Langevin, Grenoble, France as a member of the group searching for the electric dipole moment (EDM) of the neutron. The first chapter is an introduction to ultra-cold neutrons (UCN) and their use in the search for an EDM. In chapter two a description is given of the data acquisition procedure and the data analysis method as well as a discussion of the various sources of spurious EDM signals. The data taken by the author yielded the result I-fe/e = ( -3.7 ± 5.4 )xl0-25 cm, which together' with all the other data previously and subsequently collected on PN5 gives I-fe/e = ( -3.7 ± 5.4 )xlO- 25 cm. The third chapter contains some calculations, based on a simple model of the polarizer's properties, of the time dependence of the polarized UCN density in the apparatus during a data ~cquisition cycle. It. also includes the results of the experiments made in an attempt to determine experimentally the model's parameters. The other two chapters are concerned with the problem of transferring efficiently UCN from the 0.6 K volume of the 4He superthermal source to thf! 300 K EDM apparatus without allowing the heat transfer by radiation to overload the source's refrigerator. The possibility of using metal coated polypropylene windows to achieve this aim is investigated in the fourth chapter. In chapter five the infra-red transmission of the stainless steel neutron guides is estimated by calculation and then determined experimentally with a view to using lengths of cold guides to attenuate the radiation heat transfer from the apparatus to the source.
18

An Automated Approach for the Determination of the Seismic Moment Tensor in Mining Environments

Wamboldt, LAWRENCE 22 August 2012 (has links)
A study was undertaken to evaluate an automated process to invert for seismic moment tensors from seismic data recorded in mining environments. The data for this study was recorded at Nickel Rim South mine, Sudbury, Ontario. The mine has a seismic monitoring system manufactured by ESG Solutions that performs continuous monitoring of seismicity. On average, approximately 400 seismic events are recorded each day. Currently, data are automatically processed by ESG Solution's software suite during acquisition. The automatic processors pick the P- and/or S-wave arrivals, locate the events and solve for certain source parameters, excluding the seismic moment tensor. In order to solve for the moment tensor, data must be manually processed, which is laborious and therefore seldom performed. This research evaluates an automatic seismic moment tensor inversion method and demonstrates some of the difficulties (through inversions of real and synthetic seismic data) of the inversion process. Results using the method are also compared to the inversion method currently available from ESG Solutions, which requires the manual picking of first-motion polarities for every event. As a result of the extensive synthetic testing of the automatic inversion program, as well as the inversion of real seismic data, it is apparent that there are key parameters requiring greater accuracy in order to increase the reliability of the automation. These parameters include the source time function definition, source location (in turn requiring more accurate and precise knowledge of the earth media), arrival time picks and an attenuation model to account for ray-path dependent filtering of the source time function. In order to improve the automatic method three key pieces of research are needed: (1) studying various location algorithms (and the effects of increasing earth model intricacy) and automatic time picking to improve source location methods, (2) studying how the source time pulse can be accurately extracted from the seismic records, as well as the validity of various source models, and (3) studying how attenuation can be modeled more accurately to account for the filtering of the seismic waves through the earth media (in particular distortion to the source time function). / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2012-08-17 23:08:32.198
19

Poetic anatomy of the numinous creative passages into the self as beloved

Zia, Partou January 2001 (has links)
This research is shaped by the actual experience of practice: as painter and writer. My preoccupation is with the nodal moment when conscious awareness is suspended, and both the corporal and psychic involvement in realising the work almost transport one to another zone of effectiveness. This zone, which I name as the poetic zone, is where the numinous enters the ordinary. The investigation for a space/place/moment that lies beyond the logic of acceptable discourse can help initiate and give shape to a new vocabulary - visual or literary. By orchestrating a methodology, which functions on several layers, I have endeavoured to create a synthesis between painting and writing. My method in all the aspects of this research - the thesis, play scripts, studio paintings, and albums - is firmly rooted in the conscious and critical intellect, as the vehicle that helps facilitate my need in establishing a personal arena for Becoming: - a deliberate yet semi-controlled state of charged eidetic experience, whereby the 'other' of the self is met with and (perhaps) named. By probing into the specific makeup or anatomy of the poetic moment, and coming to understand how it functions within both the pragmatic and the apparently undecipherable creative processes, the artist/poet, like the mystic visionary, may give an affirmative answer to the Self, as /-that-is-not-the-other. Thus I hope that this research will contribute to the feminist project engaged in trying to delineate the divine presence in 'feminine writing', as a powerful guise and method for a clearer understanding of the psychological other.
20

Comprehensive Robustness via Moment-based Optimization : Theory and Applications

Li, Jonathan 17 December 2012 (has links)
The use of a stochastic model to predict the likelihood of future outcomes forms an integral part of decision optimization under uncertainty. In classical stochastic modeling uncertain parameters are often assumed to be driven by a particular form of probability distribution. In practice however, the distributional form is often difficult to infer from the observed data, and the incorrect choice of distribution can lead to significant quality deterioration of resultant decisions and unexpected losses. In this thesis, we present new approaches for evaluating expected future performance that do not rely on an exact distributional specification and can be robust against the errors related to committing to a particular specification. The notion of comprehensive robustness is promoted, where various degrees of model misspecification are studied. This includes fundamental one such as unknown distributional form and more involved ones such as stochastic moments and moment outliers. The approaches are developed based on the techniques of moment-based optimization, where bounds on the expected performance are sought based solely on partial moment information. They can be integrated into decision optimization and generate decisions that are robust against model misspecification in a comprehensive manner. In the first part of the thesis, we extend the applicability of moment-based optimization to incorporate new objective functions such as convex risk measures and richer moment information such as higher-order multivariate moments. In the second part, new tractable optimization frameworks are developed that account for various forms of moment uncertainty in the context of decision analysis and optimization. Financial applications such as portfolio selection and option pricing are studied.

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