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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

The effects of time on the achievement of kindergarten pupils /

Wenger, Eugene B. January 1978 (has links)
Thesis (Ph. D.)--Ohio State University, 1978. / Includes bibliographical references (leaves 191-197). Available online via OhioLINK's ETD Center.
12

1219 Colorado

Spaw, Christopher Alan January 1900 (has links)
Masters of Architecture / Landscape Architecture/Regional and Community Planning / 1219 Colorado is the documentation of the nonlinear process of design as it applies to the reconfiguration of a residential dwelling. This process is illustrated through a collection of sketches, design drawings, construction documents and images produced from 1999 to 2005. 1219 Colorado investigates materiality the physical substance of architecture, as well as the nature of thoughtful connection physical and theoretical through the process of making. The need to build, to make, to design, and explore is what drives the process. While the space of architecture is most often designed and perceived as lines on paper, it is through the making of physical models that the creative act of discovery reveals its greatest potential. The process explores the design of a model constructed at full-scale. No longer representational, the study is the product; the materials and methods are genuine. This process differs from the process of building in that the intention is no longer to construct only that which is designed. Rather the challenge is to explore beyond the design, reveal new possibilities, refine design decisions, and most importantly to take advantage of unforeseen opportunities that are revealed through the act of making. The scope of the task expanded periodically as a function of increasing knowledge of construction, declining acceptance of the quality of the existing condition and in order to accommodate an evolving set of programmatic requirements. To date the construct has under gone no less than three different design schemes, and a fourth will follow as the process continues to be refined and reconsidered. The project continues to evolve, grow, and change directions. 1219 Colorado explores design is not a linear process. Architecture is not always pretty.
13

The evaluation of using video prompting to teach a full meal preparation task to emerging adults with developmental disabilities

Cosgriff, Amanda 09 August 2019 (has links)
The purpose of the current study was to evaluate the use of a video prompting intervention to teach a full meal preparation task to emerging adults with developmental disabilities. The study also sought to identify whether cooking skills generalized across people and settings. 10participants ranging across 20-25 years participated in the study. Participants were required to understand and speak English, be able to attend to a video for at least 30seconds, follow 2-step directions, and be able to stop and start a video on an iPad. Results of the study indicate rapid acquisition from baseline to intervention for a majority of participants. Cooking skills were maintained beyond the treatment setting and person. Further, participants reported the video prompting procedure was an acceptable approach for teaching cooking skills. The results of this study provide further evidence for the use of video prompting to teach cooking skills, and to expand to use to full meal preparation for emerging adults with developmental disabilities.
14

Destructive Testing of a Full-Scale 43 Year Old Adjacent Prestressed Concrete Box Beam Bridge: Middle and West Spans

Huffman, Jonathan M. 18 April 2012 (has links)
No description available.
15

Imaging of Scattered Wavefields in Passive and Controlled-source Seismology

AlTheyab, Abdullah 12 1900 (has links)
Seismic waves are used to study the Earth, exploit its hydrocarbon resources, and understand its hazards. Extracting information from seismic waves about the Earth’s subsurface, however, is becoming more challenging as our questions become more complex and our demands for higher resolution increase. This dissertation introduces two new methods that use scattered waves for improving the resolution of subsurface images: natural migration of passive seismic data and convergent full-waveform inversion. In the first part of this dissertation, I describe a method where the recorded seismic data are used to image subsurface heterogeneities like fault planes. This method, denoted as natural migration of backscattered surface waves, provides higher resolution images for near-surface faults that is complementary to surface-wave tomography images. Our proposed method differ from contemporary methods in that it does not (1) require a velocity model of the earth, (2) assumes weak scattering, or (3) have a high computational cost. This method is applied to ambient noise recorded by the US-Array to map regional faults across the American continent. Natural migration can be formulated as a least-squares inversion to furtherer enhance the resolution and the quality of the fault images. This inversion is applied to ambient noise recorded in Long Beach, California to reveal a matrix of shallow subsurface faults. The second part of this dissertation describes a convergent full waveform inversion method for controlled source data. A controlled source excites waves that scatter from subsurface reflectors. The scattered waves are recorded by a large array of geophones. These recorded waves can be inverted for a high-resolution image of the subsurface by FWI, which is typically convergent for transmitted arrivals but often does not converge for deep reflected events. I propose a preconditioning approach that extends the ability of FWI to image deep parts of the velocity model, which significantly improves the chances for finding hydrocarbon deposits.
16

THE EFFECT OF HALF-DAY AND FULL-DAY SCHEDULES ON THE ACADEMIC ACHIEVEMENT OF KINDERGARTEN CHILDREN.

RIVERA, ANNA LYDIA FISHER. January 1985 (has links)
The purpose of the study was to determine whether a significant difference existed in the academic achievement of students as a function of attending half-day or full-day kindergartens. The hypothesis was students in full-day kindergartens will demonstrate more growth in academic achievement than students in half-day kindergartens as measured by the Head Start Measurements Battery (HSMB) in seven areas: language, math, nature/science, perception, reading, social development, and overall score. One hundred subjects were randomly selected from 158 qualified subjects that attended four Chapter 1 schools in a public school district in Southern Arizona. Four half-day and five full-day kindergartens participated. Five classes implemented a bilingual curriculum, one a Spanish curriculum, and three an English curriculum. Eventually, 74 subjects were pretested in November 1984 and posttested in May 1985. The majority of the subjects were Hispanics. Based on the literature review, the need to assess children in English/Spanish/bilingually, the need for an individually administered test of a manipulative nature, and the need for a psychometrically sound instrument, the Fall 1984 version of the Head Start Measures Battery was selected. It assesses the three-to-six-year-old child's cognitive development. The research design used was a quasi-experimental approach: the non-equivalent control group design. The independent variables were the schedules and the dependent variables were the seven areas measured by the HSMB. Mean gain scores were calculated in each of the seven areas. A t-test was used to analyze the data. The results indicated that there was a statistically significant difference (p<.05) between the mean gain scores of the half-day and full-day kindergartens (in favor of the full-day kindergartens) in language, math, and reading. The evidence failed to indicate a statistically significant difference in nature/science, perception, social development, and overall scores. In conclusion, the findings suggested that there was greater academic achievement in languages, math, and reading for full-day than for half-day kindergarten students. The findings failed to provide evidence of a difference in the academic achievement of half-day and full-day kindergarten students in nature/science, perception, social development, and overall scores.
17

Decoupled uplink-downlink user association in full-duplex small cell networks

Sekander, Silvia January 1900 (has links)
In multi-tier cellular networks, user performance is largely a ected by the varying transmit powers, distances, and non-uniform tra c loads of di erent base stations (BSs) in both the downlink (DL) and uplink (UL) directions of transmission. In presence of such heterogeneity, decoupled UL-DL user association (DUDe), which allows users to associate with di erent BSs for UL and DL transmissions, can be used to optimize network performance. Again, in-band full-duplex (FD) communi- cation is considered as a promising technique to improve the spectral e ciency of future multi-tier fth generation (5G) cellular networks. Nonetheless, due to severe UL-to-DL and DL-to-UL interference issues arising due to FD communications, the performance gains of DUDe in FD multi-tier networks are inconspicuous. To this end, this thesis develops a comprehensive framework to analyze the usefulness of DUDe in a full-duplex multi-tier cellular network. We rst formulate a joint UL and DL user association problem (with the provision of decoupled association) that maximizes the sum-rate for UL and DL transmission of all users. Since the formulated problem is a mixed-integer non-linear programming (MINLP) problem, we invoke approxi- mations and binary constraint relaxations to convert the problem into a Geometric Programming (GP) problem that is solved using Karush-Kuhn-Tucker (KKT) opti- mality conditions. Given the centralized nature and complexity of the GP problem, the solution of which serves as the upper bound for any sub-optimal solution, we formulate a distributed two-sided iterative matching game and develop a solution to obtain the solution of the game. In this game, the users and BSs rank one another using preference metrics that are subject to the externalities (i.e., dynamic interfer- ence conditions). The solution of the game is guaranteed to converge and provides Pareto-e cient stable associations. Finally, we derive e cient light-weight versions of the iterative matching solution, i.e., non-iterative matching and sequential UL-DL matching algorithms. The performances of all the solutions are critically evaluated in terms of aggregate UL and DL rates of all users, the number of unassociated users, and the number of coupled/decoupled associations. Simulation results demonstrate the e cacy of the proposed algorithms over the centralized GP solution as well as traditional coupled and decoupled user association schemes. / October 2016
18

Future cellular systems : fundamentals and the role of large antenna arrays

Biswas, Sudip January 2017 (has links)
In this thesis, we analyze the performance of three promising technologies being considered for future fifth generation (5G) and beyond wireless communication systems, with primary goals to: i) render 10-100 times higher user data rate, ii) serve 10-100 times more users simultaneously, iii) 1000 times more data volume per unit area, iv) improve energy efficiency on the order of 100 times, and iv) provide higher bandwidths. Accordingly, we focus on massive multiple-input multiple-output (MIMO) systems and other future wireless technologies, namely millimeter wave (mmWave) and full-duplex (FD) systems that are being considered to fulfill the above requirements. We begin by focusing on fundamental performance limits of massive MIMO systems under practical constraints such as low complexity processing, array size and limited physical space. First, we analyze the performance of a massive MIMO base station (BS) serving spatially distributed multi-antenna users within a fixed coverage area. Stochastic geometry is used to characterize the spatially distributed users while large dimensional random matrix theory is used to achieve deterministic approximations of the sum rate of the system. We then examine the deployment of a massive MIMO BS and the resulting energy efficiency (EE) by considering a more realistic set-up of a rectangular array with increasing antenna elements within a fixed physical space. The effects of mutual coupling and correlation among the BS antennas are incorporated by deriving a practical mutual coupling matrix which considers coupling among all antenna elements within the BS. Accordingly, the optimum number of antennas that can be deployed for a particular antenna spacing when EE is considered as a design criteria is derived. Also, it is found that mutual coupling effect reduces the EE of the massive system by around 40-45% depending on the precoder/receiver used and the physical space available for antenna deployment. After establishing the constraints of antenna spacing on massive MIMO systems for the current microwave spectrum, we shift our focus to mmWave frequencies (more than 100GHz available bandwidth), where the wavelength is very small and as a result more antennas can be rigged within a constrained space. Accordingly, we integrate the massive MIMO technology with mmWave networks. In particular, we analyze the performance of a mmWave network consisting of spatially distributed BS equipped with very large uniform circular arrays (UCA) serving spatially distributed users within a fixed coverage area. The use of UCA is due to its capability of scanning through both the azimuth as well as elevation dimensions. We show that using such 3D massive MIMO techniques in mmWave systems yield significant performance gains. Further, we show the effect of blockages and path loss on mmWave networks. Since blockages are found to be quite detrimental to mmWave networks, we create alternative propagation paths with the aid of relays. In particular, we consider the deployment of relays in outdoor mmWave networks and then derive expressions for the coverage probability and transmission capacity from sources to a destination for such relay aided mmWave networks using stochastic geometric tools. Overall, relay aided mmWave transmission is seen to improve the signal to noise ratio at the destination by around 5-10dB with respect to specific coverage probabilities. Finally, due to the fact that the current half duplex (HD) mode transmission only utilizes half the spectrum at the same time in the same frequency, we consider a multiuser MIMO cellular system, where a FD BS serves multiple HD users simultaneously. However, since FD systems are plagued by severe self-interference (SI), we focus on the design of robust transceivers, which can cancel the residual SI left after antenna and analog cancellations. In particular, we address the sum mean-squared-errors (MSE) minimization problem by transforming it into an equivalent semidefinite programming (SDP) problem. We propose iterative alternating algorithms to design the transceiver matrices jointly and accordingly show the gains of FD over HD systems. We show that with proper SI cancellation, it is possible to achieve gains on sum rate of up to 70-80% over HD systems.
19

A Fully Abstract Semantics for Event-Based Simulation

Hall, Robert J. 01 May 1987 (has links)
This paper shows that, provided circuits contain no zero-delay loops, a tight relationship, full abstraction, exists between a natural event-based operational semantics for circuits and a natural denotational semantics for circuits based on causal functions on value timelines. The paper also discusses what goes wrong if zero-delay loops are allowed, and illustrates the application of this semantic relationship to modeling questions.
20

On Primitivity and the Unital Full Free Product of Finite Dimensional C*-algebras

Torres Ayala, Francisco 2012 May 1900 (has links)
A C*-algebra is called primitive if it admits a *-representation that is both faithful and irreducible. Thus the simplest examples are matrix algebras. The main objective of this work is to classify unital full free products of finite dimensional C*-algebras that are primitive. We prove that given two nontrivial finite dimensional C*-algebras, A1 /= C, A2 /= C, the unital C*-algebra full free product A = A1 * A2 is primitive except when A1 = C^2 = A2. Roughly speaking, we first show that, except for trivial cases and the case A1 = C^2 = A2, there is an abundance of irreducible finite dimensional *-representations of A. The latter is accomplished by taking advantage of the structure of Lie group of the unitary operators in a finite dimensional Hilbert space. Later, by means of a sequence of approximations and Kaplansky?s density theorem we construct an irreducible and faithful {representation of A. We want to emphasize the fact that unital full free products of C*-algebras are highly abstract objects hence finding an irreducible *-{representation that is faithfully is an amazing fact. The dissertation is divided as follows. Chapter I gives an introduction, basic definitions and examples. Chapter II recalls some facts about *-automorphisms of finite dimensional C -algebras. Chapter III is fully devoted to prove Theorem III.6 which is about perturbing a pair of proper unital C*-subalgebras of a matrix algebra in such a way that they have trivial intersection. Theorem III.6 is the cornerstone for the rest of the results in this work. Lastly, Chapter IV contains the proof of the main theorem about primitivity and some consequences.

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