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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

RF Specification Test and Related Mixed- Signal IC Design in Bluetooth

Huang, Chien-Hsiang 26 July 2002 (has links)
In the first part of this thesis, RF specifications of the CSR Bluetooth module were tested rigorously by means of proper equipment setup and manipulation. The tested parameters in the transmitter include output power, spectrum and modulation characteristics. The tested parameters in the receiver include sensitivity and received signal strength indicator. The second part of this thesis was mainly focused on some mixed-signal integrated-circuit designs that can be generally applied to the Bluetooth RF front-end. The design examples include the phase frequency detector, charge pump, and frequency divider in the applications of phase-locked loop. A transconductance-capacitor low-pass filter with tunable cut-off frequencies was also designed to suppress the spurious signals from RF front-end into baseband.
102

The Study of CO2 Fixation on The Magnesium-Lithium Mixed Metal Complexes

Chen, Shin-Yi 18 August 2003 (has links)
The reaction of Mg(NPh2)2 with LiNR2 (R= SiMe3, NiPr, NiBu) generated the same product, [Mg(NPh2)3(THF)][Li(THF)4] which was identified by 1H-NMR and X-ray crystallography. The magnesium-lithium mixed metal complex reacted with excess carbon dioxide in the ice bath to generate the tetralithium complex, Li4(O2CNPh2)4(THF)4 which was identified by 1H-NMR, 13C-NMR, IR, and X-ray crystallography.
103

Wide Range Bidirectional Mixed-Voltage-Tolerant I/O Buffer

Chang, Wei-chih 25 June 2008 (has links)
The thesis is composed of two topics : a fully bidirectional mixed-voltage-tolerant I/O buffer using a clamping dynamic gate bias generator and a wide range fully bidirectional mixed-voltage-tolerant I/O buffer with a calibration function. The first topic, a mixed-voltage-tolerant I/O buffer implemented in 2P4M 0.35 £gm CMOS process, comprises a low-power bias circuit with clamping transistors in a feedback loop, a power supply level detector circuit, a voltage level converter circuit, a logic switch circuit, a dynamic driving detector circuit, and a clamping dynamic gate bias generator. The proposed design can transmit and receive digital signals with voltage levels of 5/3.3/1.8 V without any gate-oxide overstress and leakage current path in different voltage interface applications. The second topic, a 0.9 V to 5.0 V (0.9/1.2/1.8/2.5/3.3/5 V) mixed-voltage-tolerant I/O buffer carried out in 2P4M 0.35 £gm CMOS technology, contains a dynamic gate bias generator to provide appropri¬ate gate voltages for the output stage composed of stacked PMOS and stacked NMOS, an I/O buffer which can transmit the signal with a higher voltage level (VDDH), a floating N-well circuit to remove the body effect at the output PMOS, and a dynamic driving detector to balance the turn-on voltages for the pull-up PMOS and pull-down NMOS in the output stage. The duty cycle of the output signal of the proposed I/O buffer can then be equalized even if the output stage power supply is biased at a low voltage. In order to adapt to wide range input voltage applications, a logic calibration circuit is added in the input buffer.
104

Privatization and Subsidization in Mixed Oligopoly

Ding, Shie-chao 15 October 2009 (has links)
none
105

The identity development of mixed race individuals in Canada

Das, Monica. January 2010 (has links)
Thesis (M. Ed.) -- University of Alberta, 2010. / "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Education in Psychological Studies in Education, Educational Psychology, University of Alberta." Title from pdf file main screen (viewed on February 11, 2010) Includes bibliographical references.
106

Optimization and separation for structured submodular functions with constraints

Yu, Jiajin 08 June 2015 (has links)
Various kinds of optimization problems involve nonlinear functions of binary variables that exhibit a property of diminishing marginal returns. Such a property is known as submodularity. Vast amount of work has been devoted to the problem of submodular optimization. In this thesis, we exploit structural information for several classes of submodular optimization problems. We strive for polynomial time algorithms with improved approximation ratio and strong mixed-integer linear formulations of mixed-integer non-linear programs where the epigraph and hypograph of submodular functions of a specific form appear as a substructure together with other side constraints. In Chapter 2, we develop approximation algorithms for the expected utility knapsack problem. We use the sample average approximation framework to approximate the stochastic problem as a deterministic knapsack-constrained submodular maximization problem, and then use an approximation algorithm to solve the deterministic counterpart. We show that a polynomial number of samples are enough for a deterministic approximation that is close in relative error. Then, exploiting the strict monotonicity of typical utility functions, we present an algorithm that maximizes an increasing submodular function over a knapsack constraint with approximation ratio better than the classical $(1-1/e)$ ratio. In Chapter 3, we present polyhedral results for the expected utility knapsack problem. We study a mixed-integer nonlinear set that is the hypograph of $f(a'x)$ together together with a knapsack constraint. We propose a family of inequalities for the convex hull of the nonlinear set by exploiting both the structure of the submodular function $f(a'x)$ and the knapsack constraint. Effectiveness of the proposed inequalities is shown by computational experiments on expected utility maximization problem with budget constraint using a branch-and-cut framework. In Chapter 4, we study a mixed-integer nonlinear set that is the epigraph of $f(a'x)$ together with a cardinality constraint. This mixed-integer nonlinear set arises as a substructure in various constrained submodular minimization problems. We develop a strong linear formulation of the convex hull of the nonlinear set by exploiting both the submodularity of $f(a'x)$ and the cardinality constraint. We provide a full description of the convex hull of the nonlinear set when the vector a has identical components. We also develop a family of facet-defining inequalities when the vector a has nonidentical components. We demonstrate the effectiveness of the proposed inequalities by solving mean-risk knapsack problems using a branch-and-cut framework.
107

Effects of shallow gas development on relative abundances of grassland songbirds in a mixed-grass prairie

Rodgers, Jennifer Anne 02 August 2013 (has links)
Grassland bird species have declined more than birds of any other region in North America, and industrial development may exert additional pressure on these species. I evaluated the effects of natural gas infrastructure on the relative abundances of grassland songbirds in southeastern Alberta, Canada using point counts at sites with well densities ranging from 0 to 20 per 1×1 mile. Generalized Linear Mixed Models were used to evaluate effects of infrastructure on birds, and parsimonious models were selected using Akaike’s Information Criterion. Vegetation near infrastructure was shorter and sparser than locations farther away, but was unlikely to have driven responses to infrastructure by birds. Gas wells may have acted as “artificial shrubs” attracting species such as vesper sparrow (Pooecetes gramineus) and western meadowlark (Sturnella neglecta) that use vegetation for perching, while other species, such as Sprague’s pipit (Anthus spragueii) and chestnut-collared longspur (Calcarius ornatus), had higher abundances farther from wells.
108

When West meets East on painting

Kawasaki, Kuniko January 1980 (has links)
There is no abstract available for this thesis.
109

Sheng : the mixed language of Nairobi

Rudd, Philip W. January 2008 (has links)
The purpose of this dissertation is to determine whether Sheng, a language spoken in the Eastlands area of Nairobi, Kenya, is a mixed language (incorporating Swahili, English and local vernaculars). The study focuses on the lexicon and morphosyntax, but social factors are examined as well. Three broad research questions are addressed: (1) Does Sheng have a core vocabulary separate from that of Swahili? (2) How do the system morphemes of Sheng compare with those of Swahili? And (3) in what manner does Sheng provide its speakers a new identity?With respect to question one, the core lexicon, like Russenorsk's, Trio-Ndjuka's and Michif's, manifests a nearly fifty-fifty split in Sheng (52% Swahili; 48% other), making it a mixed language lexically.As for question two, the analysis reveals that Sheng has a composite morphosyntax. No object or relative affixes are marked on the verb. Predicate-argument structure from English has provided a null relativizer. The aerial feature imperfective suffix -a(n)g- is preferred 68% of the time. Noun classes show convergence leveling. The marker ma- serves as the generic plural. The diminutive markers, (ka-, to-), constitute a complete non-Swahili subsystem. Consequently, Sheng is also a mixed language morphosyntactically.In reference to question three, a negative correlation exists between competence in Sheng and income and housing. Though the affluent display a negative attitude towardSheng, they agree with the lower socio-economic groups that Sheng has a communicative utility in metropolitan Kenya. A comparison of the usage in the different residential areas establishes that community-wide grammatical norms (i. e., stability) exist in Sheng. Over two decades without institutional support for Swahili provided a niche in which Sheng, a non-standard language variety, flourished and a new urban identity emerged.Eastlanders walk a linguistic tightrope, balancing between the labels mshamba (`rube') and Mswahili (`slick talker'). However, Sheng provides a sociolinguistic embodiment symbolizing what nuances their existence. Over time, speakers formed a new identity group, whose language was initially `off target' (1899-1963) but subsequently became deliberate postcolonially. Finally, the name of the language itself (Sheng < LiSheng < lish-eng < English) results from and is symbolic of this social transformation. / Department of English
110

Effects of shallow gas development on relative abundances of grassland songbirds in a mixed-grass prairie

Rodgers, Jennifer Anne 02 August 2013 (has links)
Grassland bird species have declined more than birds of any other region in North America, and industrial development may exert additional pressure on these species. I evaluated the effects of natural gas infrastructure on the relative abundances of grassland songbirds in southeastern Alberta, Canada using point counts at sites with well densities ranging from 0 to 20 per 1×1 mile. Generalized Linear Mixed Models were used to evaluate effects of infrastructure on birds, and parsimonious models were selected using Akaike’s Information Criterion. Vegetation near infrastructure was shorter and sparser than locations farther away, but was unlikely to have driven responses to infrastructure by birds. Gas wells may have acted as “artificial shrubs” attracting species such as vesper sparrow (Pooecetes gramineus) and western meadowlark (Sturnella neglecta) that use vegetation for perching, while other species, such as Sprague’s pipit (Anthus spragueii) and chestnut-collared longspur (Calcarius ornatus), had higher abundances farther from wells.

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