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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.
21

Pricing Principles, Efficiency Concepts and Incentive Models in Swedish Transport Infrastructure Policy

Hasselgren, Björn January 2013 (has links)
In this article the shift of the Swedish goverment´s policies for the financing through taxation, fees and prices paid for the use of roads and railroads from 1945 until the 2010s is discussed. It is argued that the shift from a full-cost coverage principle to a short term social marginal cost principle can be seen in the light of the controversy between a Coasean and a Pigovian perspective. The Coasean perspective furthers an institutional view where organizations and dynamic development matters while the Pigovian perspective furthers a welfare economic equilibrium view where organizations are less focused. It is argued that the shift in policies coincided with less interest and focus on the organizational perspective and incentives for organizational efficiency, which can be seen in the public documents from the time. The government seems to have been guided by a mar ket failure stance since the 1970s which has motivated growing intervention, following a mar ket-economy stance in the first 25 years after the nationalization of roads and railroads. A current opening in transport infrastructure policies with more room for alternative financing, user charges and fees might, even though also consistent with short term social marginal cost principles, signal a revival of a perspective more in line with the Coasean view. / <p>QC 20130614</p>
22

Nascent Dreams

Ingmire, Bryce 06 September 2012 (has links)
Nascent Dreams (2012) is a work for full orchestra that explores the elasticity of form as musical analogy. In a programmatic context, each thematic section can be interpreted as representing landscapes or events encountered while dreaming. Listeners are privy to the nascency of each section before the music whisks one away to the next soundscape. Musically, the work emphasizes melody and lyricism in order to establish a song-like quality throughout.
23

A Systematic Investigation of Shear Connections Between Full-Depth Precast Panels and Precast Prestressed Bridge Girders

Brey, Robert W. 2010 May 1900 (has links)
Full-depth precast panels are used in concrete bridges to provide several benefits such as faster construction, lower cost and reduced constructional hazard. However, one construction drawback is that connectors are required to transmit horizontal shear across the interface between the girder and deck. Shear connector performance is characterized by a series of experiments performed on part of a bridge system that mimics a full-depth precast deck on concrete girder with a pocket-connector-haunch system. Following initial breakaway of the adhesive bond within the haunch region, the specimens slide with frictional resistance provided by the clamping force of the anchor bolt. This leads to bolt yield with an observed sliding friction coefficient of 0.8 (+/- 20%) with lower values occurring at higher displacements. It is concluded that for a viable connector system to be developed a key feature is to have sufficient stirrups in the neighborhood of the anchor bolt to form a non-contact splice and to ensure the high pull-out force can be sustained without leading to premature beam failure. The successful implementation of a full-depth precast deck-panel system requires the use of a viable design methodology that properly accounts for system behavior. The design of a deck-haunch-girder system uses a truss modeling approach to design for the shear forces created by service loading. The truss model approach is considered more suitable for a concrete member due to the premise that the member will be substantially cracked at an ultimate limit state and that traditional beam theory does not account for the decreased ability of shear stresses to transfer across open cracks. Experimental results from Chapter II, such as the friction coefficient mu, are used along with a previously developed crack angle model to layout the geometry of the truss within a deck-panel span. Design solutions are presented utilizing the Rock Creek Bridge in Parker County, Texas as an example structure.
24

The Application of the HEMS Energy Conservation Strategies in Taiwan

Chang, Kai-chiang 13 July 2009 (has links)
ABSTRACT The HEMS system has been gaining global attention due to its huge potential for home application in conserving energy. It is the goal of this research to study to analyze: 1. The Intelligent Operational Strategies under local Weather Conditions 2. Full-scale Experimental Investigation of the HEMS system, including the HVAC and Lighting Controls 3. Energy Savings Effect of each HEMS strategy developed and its Economic Feasibility The experimental result indicated that the HEMS system can be established efficiently in applying: For Air-conditioning Systems: Intermittent Ac PMV-assisted AC Mode DSM-controlled AC mode Predictive Control AC Mode Free-cooling Mode, and For Lighting Systems : Lighting on Demand Mode Task Lighting Sequential Control Lighting Daylighting Humane-sensored Lighting The experimental result indicated that over 30% energy savings can be experienced with huge potential for wide engineering applications.
25

Full Duplex Multiuser MIMO with Massive Arrays

Wannas, Hussain January 2014 (has links)
Half-Duplex Multiuser Multiple-Input Multiple-Output (HD MU-MIMO) systemscurrently employed in communication systems are not experiencing the selfinterference(SI) problem but they are not optimal in terms of efficiency and interms of resources used (time and frequency resources). Ignoring the effect of largescalefading, we start by explaining the uplink (UL) and downlink (DL) parts ofthe MU-MIMO system and how the sum-rate is calculated. We also introduce thethree linear receivers/precoders, Maximum-Ratio Combining (MRC)/Maximum-Ratio Transmission (MRT), Zero-Forcing (ZF), and Minimum Mean-Square Error(MMSE) and which of the three types is going to be used in the study of Full-Duplex Multiuser Multiple-input Multiple-output (FD MU-MIMO) system. Thenwe introduce FD MU-MIMO system, and how the equation used to calculate thesum-rate of the UL part changes when the SI occurs, and why SI problem is notpresent in the DL part. Next, we introduce the spectral efficiency (SE), and howto calculate it and why it is taken as a parameter to compare HD and FD systems.Also the effect of SI on FD MU-MIMO system is presented through simulationgraphs, then we move to show how to reduce SI effect by increasing the number ofantennas in the base-station (BS). Lastly, we take the effect of large scale fading inorder to reach a simple statistical model in the form cumulative distribution function(CDF) graph for different values of SI and compare those of FD MU-MIMOsystem to HD MU-MIMO. The results show that FD MU-MIMO together withmassive MIMO technology is very promising and would save time and frequencyresources which means an increase in the SE but SI must be below a certain level.
26

Effective Design and Control of Full Depth Reclaimed Pavements

Salah, Peter 25 July 2013 (has links)
The traditional method of repairing damaged roads in Atlantic Canada has been to place a hot mix asphalt overlay over the existing road. Though this method provides a new, smooth wearing surface to drive on, it is merely a short term fix. With time, the cracks in the original pavement will reflect to the surface of the new pavement, resulting in failure of the overlay. An alternative option gaining more prominence is the use of a Full Depth Reclamation (FDR) technique, which involves pulverizing the flexible pavement, along with a portion of the underlying layer. This material is then stabilized and recompacted to produce a new base layer that is free of damage. Though FDR has been used for a number of years, there are still problems with variability in the strength of the materials in some projects. It is hypothesized that some of these problems are due to variability and poor quality in the reclaimed materials. It is believed that current pulverization methods contribute to the variability being observed in these materials. Two FDR projects employing different pulverization control methods were studied to examine how the consistency of the reclaimed materials can be improved through the use of a Ground Penetrating Radar (GPR) survey to map the variability in the depth of the pavement. Controlling the thickness ratio of asphalt concrete to granular base materials being pulverized was shown to improve the consistency of materials, properties, and performance. The second phase of this research project studied how improving the gradation of the reclaimed materials with the addition of a crusher dust might result in improved performance of stabilized base materials, in this case stabilized with expanded asphalt. The effect of construction variability on the improved materials was also studied by varying both the moisture content, and asphalt content from optimum conditions, as might be expected during construction. Results indicated that the quality of the stabilized FDR materials can be significantly improved by bringing the material gradation closer to the theoretical maximum density gradation. The performance of the stabilized materials can be affected by both the mixing moisture content, and the asphalt content used during stabilization. This suggests that effective quality control, and stricter specifications on the constructed product would result in more reliable, effective FDR pavements. / A study on the control of the consistency of pulverized FDR materials, as well as a study examining how to improve the performance of these pulverized materials.
27

Full-time mentors: a qualitative study of new teacher perceptions

Armstrong, Patrick Sean 22 December 2010 (has links)
This study examines the perceptions of new teachers regarding the benefits of full-time mentorship based on one particular new teacher induction program. Six new teachers and three mentors were interviewed in this study. Data indicated that full-time mentors could effectively introduce new teachers into the teaching profession if certain conditions were present. New teachers perceived the following benefits from effective full-time mentorship: increased confidence in their abilities, opportunities for non-evaluative observation and feedback, practice teaching of lessons prior to administrative evaluations, support with resources and materials specific to their situation, and the opportunity to ask critical questions in complete confidence. However, these benefits were not perceived when an unmanageable mentor-to-teacher ratio was present. One finding not prevalent in the literature was the characteristic of disassociation whereby teachers new to the profession had difficulties disassociating their professional work lives from their personal lives. The suggestion is made that further study is warranted to determine if the characteristic of disassociation could be used as a predictor of new-teachers at risk of leaving the profession. This study concludes by making eight recommendations for improving full-time mentor support and new teacher induction.
28

Full-time mentors: a qualitative study of new teacher perceptions

Armstrong, Patrick Sean 22 December 2010 (has links)
This study examines the perceptions of new teachers regarding the benefits of full-time mentorship based on one particular new teacher induction program. Six new teachers and three mentors were interviewed in this study. Data indicated that full-time mentors could effectively introduce new teachers into the teaching profession if certain conditions were present. New teachers perceived the following benefits from effective full-time mentorship: increased confidence in their abilities, opportunities for non-evaluative observation and feedback, practice teaching of lessons prior to administrative evaluations, support with resources and materials specific to their situation, and the opportunity to ask critical questions in complete confidence. However, these benefits were not perceived when an unmanageable mentor-to-teacher ratio was present. One finding not prevalent in the literature was the characteristic of disassociation whereby teachers new to the profession had difficulties disassociating their professional work lives from their personal lives. The suggestion is made that further study is warranted to determine if the characteristic of disassociation could be used as a predictor of new-teachers at risk of leaving the profession. This study concludes by making eight recommendations for improving full-time mentor support and new teacher induction.
29

Efficient Estimation in a Regression Model with Missing Responses

Crawford, Scott 2012 August 1900 (has links)
This article examines methods to efficiently estimate the mean response in a linear model with an unknown error distribution under the assumption that the responses are missing at random. We show how the asymptotic variance is affected by the estimator of the regression parameter and by the imputation method. To estimate the regression parameter the Ordinary Least Squares method is efficient only if the error distribution happens to be normal. If the errors are not normal, then we propose a One Step Improvement estimator or a Maximum Empirical Likelihood estimator to estimate the parameter efficiently. In order to investigate the impact that imputation has on estimation of the mean response, we compare the Listwise Deletion method and the Propensity Score method (which do not use imputation at all), and two imputation methods. We show that Listwise Deletion and the Propensity Score method are inefficient. Partial Imputation, where only the missing responses are imputed, is compared to Full Imputation, where both missing and non-missing responses are imputed. Our results show that in general Full Imputation is better than Partial Imputation. However, when the regression parameter is estimated very poorly, then Partial Imputation will outperform Full Imputation. The efficient estimator for the mean response is the Full Imputation estimator that uses an efficient estimator of the parameter.
30

Active labour market programs and attitudes towards globalization

Stretch, Kenneth James. January 1900 (has links)
Thesis (M.A.). / Written for the Dept. of Political Science. Title from title page of PDF (viewed 2008/01/14). Includes bibliographical references.

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