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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.
451

Some current issues in the statistical analysis of spillovers

Gumprecht, Daniela, Gumprecht, Nicole, Müller, Werner January 2003 (has links) (PDF)
Spillover phenomena are usually statistically estimated on the basis of regional and temporal panel data. In this paper we review and investigate exploratory and confirmatory statistical panel data techniques. We illustrate the methods by calculations in the stetting of the well known Research and Development Spillover study by Coe and Helpman (1995). It will be demonstrated that alternative estimation techniques that are well compatible with the data can lead to opposite conclusions. (author's abstract) / Series: Working Papers Series "Growth and Employment in Europe: Sustainability and Competitiveness"
452

Fertility of Beef Recipients Following a Fixed-Time Embryo Transfer Protocol that Includes Follicle Stimulating Hormone Diluted in Hyaluronan

Thorne, Jacob Westley 03 October 2013 (has links)
This study was performed to test the viability of administering a single 40 mg dose of Folltropin-V® (FSH, Bioniche Animal Health) diluted in SRF (MAP-5 50, Sodium Hyaluronate, Bioniche Animal Health) on day 5 of a recipient synchronization protocol to beef cows to evaluate its effect on recipient fertility. All recipients were administered an estradiol 17beta (2.5 mg, IM) and progesterone (50 mg, IM) combination injection on day 0 and a CIDR® (progesterone 1.34 g, Pfizer Animal Health) was inserted. Lutalyse® (dinoprost tromethamine, Pfizer Animal Health, 25 mg, IM) was administered at the time of CIDR removal on day 7, and estradiol 17beta (1 mg, IM) was administered on day 8. On day 16, the presence of at least one corpus luteum (CL), detected via ultrasound, resulted in the recipient receiving an embryo (both fresh and frozen-thawed embryos were used). Embryos were not transferred into cows that did not show the presence of a CL. Dependent variables for which data were collected included circulating progesterone levels at the time of transfer, number of CLs and CL diameter, circumference, and area; measured in millimeters. The study (n=572) consisted of a treatment group (n=268) and a control group (n=304), and included both Bos indicus (Brahman influenced) crossbred (n=115) and Bos taurus (Angus based) cows (n=457). Pregnancy rates for Treated recipients (40.67%A) and Control recipients (52.96%B) differed (P<.05). There was no difference in the mean number of CLs per recipient for Treated (1.14 +/- .03) and Control (1.10 +/- .02) cows, nor was there a difference in progesterone (P4) at the time of transfer for Treated (3.14 +/- .40 ng/mL) and Control (3.23 +/- .18 ng/mL) recipients. Overall, the inclusion of Folltropin-V® diluted in hyaluronan in a FTET synchronization protocol did not improve the fertility of beef recipients.
453

Cross-layer Optimization in Wireless Multihop Networks

Shabdanov, Samat 06 December 2012 (has links)
In order to meet the increasing demand for higher data rates, next generation wireless networks must incorporate additional functionalities to enhance network throughput. Multihop networks are considered as a promising alternative due to their ability to exploit spatial reuse and to extend coverage. Recently, industry has shown increased interest in multihop networks as they do not require additional infrastructure and have relatively low deployment costs. Many advances in physical and network layer techniques have been proposed in the recent past and they have been studied mostly in single-hop networks. Very few studies, if any, have tried to quantify the gains that these techniques could provide in multihop networks. We investigate the impact of simple network coding, advanced physical layer and cooperative techniques on the maximum achievable throughput of wireless multihop networks of practical size. We consider the following advanced physical layer techniques: successive interference cancellation, superposition coding, dirty-paper coding, and some of their combinations. We achieve this by formulating several cross-layer frameworks when these techniques are jointly optimized with routing and scheduling. We also formulate power allocation subproblems for the cases of continuous power control and superposition coding. We also provide numerous engineering insights by solving these problems to optimality.
454

Endogenous Growth Testing In The European Union And Developing Countries: Taxation, Public Expenditure And Growth

Derin, Pinar 01 January 2003 (has links) (PDF)
In endogenous growth models, in contrast to the neoclassical growth models, government expenditure and taxation have an effect on the long run growth rate. In this thesis I examine whether the empirical evidence support the predictions of endogenous growth models or the neoclassical growth models in relation to fiscal policy. For this purpose I use panel data for fifteen European Union (EU) member and thirty-three developing countries between the years 1970 and 1999. I specifically test the following two propositions. The first proposition states that distortionary taxation decreases growth while non-distortionary taxation does not. The second, states that productive government expenditure increases growth while non-productive expenditure does not. The empirical results are quite different between European Union countries and developing countries. The results do not support endogenous growth especially for developing countries.
455

價格與數量的實證研究 :以大尺寸的TFT LCD panels為例

楊志常, Chih-Chang Ken Yang Unknown Date (has links)
The purpose of this research is to understand and explain the TFT LCD industry phenomenon of oversupply vs. shortage and its impacts on the prices and quantities of individual TFT LCD makers. Also, to look for any fixed effects (if any exist) due to specific company and due to specific time. We employ a fixed effect model to estimate impacts of individual traded quantity on price and impacts of individual price on traded quantity. Using the panel data covering 16 makers and 24 months, our results reveal that the TFT LCD panel is highly quantity inelastic of the traded price but greatly price elastic of the traded quantity. With regard to fixed effect, the empirical result reveals there were significant time effects of price for some periods of time while there were significant time effects of quantity for some sizes of panels. Supply and demand could be one of the factors determining the time effects. As to the company fixed effect, most of company fixed effects of quantity prices were found significant whereas company fixed effects of price were not. Market shares and country of origin can be significant factors determining the company fixed effect of quantity. Keywords: Panel Data, Fixed Effect Model, Quantity Elasticity, Price Elasticity, Company Fixed Effect, Time Fixed Effect, TFT LCD
456

Design and comparison of DIN removal rates between five 'low-tech' fixed film biological reactors treating aquaculture wastewater on Coconut Island

Roth, Lauren Carter January 2005 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 64-73). / xi, 73 leaves, bound ill. 29 cm
457

On dental ceramics and their fracture : a laboratory and numerical study

Kou, Wen January 2010 (has links)
Background Surface treatments and irregularities in the surfaces may affect the fracture of ceramics. The effects of various treatments on the surface texture of different types of ceramic cores/substructures was therefore qualitatively, quantitatively and numerically evaluated. Since fractures in ceramics are not fully understood, the fracture behavior in dental ceramic core/substructures was also studied using both established laboratory methods and newly developed numerical methods. Methods The surfaces of dental ceramic cores/substructures were studied qualitatively by means of a fluorescence penetrant method and scanning electron microscopy, quantitatively evaluated using a profilometer and also numerical simulation. In order to study fracture in zirconia-based fixed partial denture (FPD) frameworks, fractographic analysis in combination with fracture tests and newly developed two-dimensional (2D) and three-dimensional (3D) numerical modeling methods were used. In the numerical modeling methods, the heterogeneity within the materials was described by means of the Weibull distribution law. The Mohr–Coulomb failure criterion with tensile strength cut-off was used to judge whether the material was in an elastic or failed state. Results Manual grinding/polishing could smooth the surfaces on some of the types of dental ceramic cores/substructures studied. Using the fluorescence penetrant method, no cracks/flaws apart from milling grooves could be seen on the surfaces of machined zirconia-based frameworks. Numerical simulations demonstrated that surface grooves affect the fracture of the ceramic bars and the deeper the groove, the sooner the bar fractured. In the laboratory tests the fracture mechanism in the FPD frameworks was identified as tensile failure and irregularities on the ceramic surfaces could act as fracture initiation sites. The numerical modeling codes allowed a better understanding of the fracture mechanism than the laboratory tests; the stress distribution and the fracture process could be reproduced using the mathematical methods of mechanics. Furthermore, a strong correlation was found between the numerical and the laboratory results. Conclusion Based on the findings in the current thesis, smooth surfaces in areas of concentrated tensile stress would be preferable regarding the survival of ceramic restorations, however, the surfaces of only some of the ceramic cores/substructures could be significantly affected by manual polishing. The newly developed 3D method clearly showed the stress distribution and the fracture process in ceramic FPD frameworks, step by step, and seems to be an appropriate tool for use in the prediction of the fracture process in ceramic FPD frameworks.
458

Development of a diffusion based ethanol delivery system to promote reducing environments for the bioremediation of contaminated groundwater

Grassi, Michelle Elenore January 2005 (has links)
[Truncated abstract] An ethanol delivery system, consisting of silicone (poly(dimethylsiloxane)) tubing coiled and shaped as mats, was characterised and evaluated for its potential to act as a permeable reactive barrier (PRB), to promote reducing conditions and enable the enhanced bioremediation of a variety of groundwater contaminants in situ. Aqueous ethanol solutions were recirculated through the inner volume of the silicone polymer tubing in the mat, to allow permeation and delivery of ethanol by diffusion through the tubing walls to a target contamination zone. The aim of the system was to provide control over subsurface geochemistry by overcoming carbon source limitations, and as a result stimulate indigenous bacteria to remove contaminants. The physical properties of the silicone tubing were initially characterised, which included the determination of the ethanol sorption and diffusion properties of the tubing. A model for the mass of ethanol transferred via diffusion from an aqueous solution on the inner volume of a length of polymer tubing was developed to enable prediction of the ethanol delivery capacity of the silicone polymer mats. A number of large-scale laboratory column studies were then conducted to validate this ethanol mass delivery model, and to evaluate the use of silicone polymer mats to deliver ethanol and promote the biodegradation of a range of different contaminated groundwaters. The laboratory column experiments were observed to produce ethanol mass flux delivery statistically similar to that predicted by the model; however this was only with the application of an effective diffusion coefficient within the model, which was determined from the model under subsurface-simulated conditions. Ethanol delivery using the silicone tubing polymer mat system was also quantified in a pilot field-scale demonstration. The mass of ethanol delivery in the field was shown to be within the range of model-predicted ethanol delivery; however delivery was not as consistent and predictable as that observed in the column studies. Successful ethanol enhanced nitrate contamination removal (via denitrification) was observed at a field scale. For field applications, this innovative polymer mat amendment delivery system may provide targeted, predictable and cost-effective amendment delivery compared to aqueous injection methods for groundwater bioremediation, however, knowledge and quantification of the hydrogeology of the particular field site is required. Two other ethanol-driven biologically-mediated contaminant removal processes were also investigated in the laboratory-scale soil column studies, and included the assessment of the removal of dissolved metals/sulfate via sulfate reduction and metalsulfide precipitation, and the removal of trichloroethene via reductive dechlorination.
459

A pantographic evaluation of temporomandibular joint dysfunction in patients being treated with fixed restoration a thesis submitted in partial fulfillment ... in restorative dentistry (crown and bridge) ... /

Alpine, Keith D. January 1984 (has links)
Thesis (M.S.)--University of Michigan, 1984.
460

A patient utility analysis of treatment modalities for replacing a single missing tooth a thesis submitted in partial fulfillment ... for the degree of Master of Science in Restorative Dentistry ... /

Kanjirath, Preetha Panose. January 2003 (has links)
Thesis (M.S.)--University of Michigan, 2003. / Includes bibliographical references.

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