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Sengupta, Amitdyuti. "Preliminary Hydrogen Sulfide Emission Factors and Emission Models for Wastewater Treatment Plant Headworks." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1829.
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Generation of hydrogen sulfide (H2S) is a common phenomenon from wastewater collection, transport, and treatment processes. Impacts of H2S emissions from wastewater include corrosion and reduction in the service life of wastewater infrastructure, odor nuisance in the community, and health impacts on wastewater operations and maintenance personnel (Neilsen, et al. WEFTEC 2006).
Conventional odor control studies performed by municipalities to design their individual odor/corrosion control strategies largely depend on establishing a dilution to detection threshold (D/T) ratio and ascertaining the recognition threshold (R/T) for air samples collected from the study area. These conventional odor studies based on grab samples using R/T and D/T technique using a few days of data have a number of limitations and potentially lead to inaccurate conclusions. However, H2S emission studies using continuous air monitoring is expensive and time consuming.
The objective of this research is to understand the feasibility of utilizing emission factors as a tool to predict hydrogen sulfide emissions from headworks of four different Jefferson Parish, Louisiana wastewater treatment plants (WWTP). Proposed model(s) developed for predicting H2S emission factors that depend on wastewater parameters should be convenient for the municipalities to use as the data required is monitored routinely. Use of H2S emission models should assist rapid identification of H2S emission hot spots, optimize H2S control strategies, predict potential health risks, prevent community odor nuisance, and ascertain infrastructure corrosion.
This dissertation attempts to; i) develop a research methodology, ii) identify instruments required, iii) generate emission factor ranges and compare their sensitivity to wastewater parameters, iv) generate preliminary empirical emission models based on flow treated, population serviced and area served by a treatment plant for each sampling location and v) provide a roadmap for future research opportunities to refine the models generated as part of this dissertation.
Key words: emission model, emission factor, emission ranges, hydrogen sulfide, odor control, air quality, wastewater treatment.
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Tsanakas, Nikolaos. "Emission estimation based on traffic models and measurements." Licentiate thesis, Linköpings universitet, Kommunikations- och transportsystem, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-155771.
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Traffic congestion increases travel times, but also results in higher energy usage and vehicular emissions. To evaluate the impact of traffic emissions on environment and human health, the accurate estimation of their rates and location is required. Traffic emission models can be used for estimating emissions, providing emission factors in grams per vehicle and kilometre. Emission factors are defined for specific traffic situations, and traffic data is necessary in order to determine these traffic situations along a traffic network. The required traffic data, which consists of average speed and flow, can be obtained either from traffic models or sensor measurements. In large urban areas, the collection of cross-sectional data from stationary sensors is a costefficient method of deriving traffic data for emission modelling. However, the traditional approaches of extrapolating this data in time and space may not accurately capture the variations of the traffic variables when congestion is high, affecting the emission estimation. Static transportation planning models, commonly used for the evaluation of infrastructure investments and policy changes, constitute an alternative efficient method of estimating the traffic data. Nevertheless, their static nature may result in an inaccurate estimation of dynamic traffic variables, such as the location of congestion, having a direct impact on emission estimation. Congestion is strongly correlated with increased emission rates, and since emissions have location specific effects, the location of congestion becomes a crucial aspect. Therefore, the derivation of traffic data for emission modelling usually relies on the simplified, traditional approaches. The aim of this thesis is to identify, quantify and finally reduce the potential errors that these traditional approaches introduce in an emission estimation analysis. According to our main findings, traditional approaches may be sufficient for analysing pollutants with global effects such as CO2, or for large-scale emission modelling applications such as emission inventories. However, for more temporally and spatially sensitive applications, such as dispersion and exposure modelling, a more detailed approach is needed. In case of cross-sectional measurements, we suggest and evaluate the use of a more detailed, but computationally more expensive, data extrapolation approach. Additionally, considering the inabilities of static models, we propose and evaluate the post-processing of their results, by applying quasi-dynamic network loading.
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Green, S. F. "Infrared observations and thermal emission models of asteroids." Thesis, University of Leicester, 1985. http://hdl.handle.net/2381/35899.
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A review of the classification of asteroids according to their orbital and physical properties is presented and the technique of numerical taxonomy is applied to catalogued optical data. The size distribution of minor bodies is of fundamental importance for theories of the origin and formation of the Solar System. Methods of diameter determination are reviewed with particular reference to the radiometric method. Thermal emission models of asteroids are essential for the reduction of infrared observations to obtain radiometric diameters and albedos. Various thermal models are described, with an emphasis on the assumptions made, and their limitations. The models are applied to observations in the 8-13?m region to examine possible variations of emissivity with wavelength, to remove the thermal component from reflection spectra in the 3-4?m region, and to determine the nature of the surface of the unusual asteroid (3200) 1983TB. The Infrared Astronomical Satellite (IRAS) was launched in 1983 to provide an all-sky survey in four infrared wavebands. In order to prevent detections of the thermal emission from moving objects from being lost, software was written to search the rejected survey data in near real-time. As well as detecting several hundred numbered asteroids and five known comets, two main belt asteroids, two Apollo asteroids, six comets and an infrared tail on comet Tempel-2 were discovered. A description of the moving object software and its implementation is presented, together with estimates of the selection effects and completeness of the search, and analysis of the data. The ground-based observations of the Apollo asteroid (3200) 1983TB do not support the cometary nucleus hypothesis inferred from its orbital characteristics. A preliminary analysis of some IRAS additional observations of asteroids is also presented.
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Winkelmann, Christopher Todd. "Micro-imaging characterization of mouse models of metastasis." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/5820.
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Thesis (Ph. D.)--University of Missouri-Columbia, 2005.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. "December 2005" Includes bibliographical references.
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Yin, Jun, and 尹俊. "A continuum modeling approach to transport emission problems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46603499.
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Pallister, I. C. "Models of x-ray emission from clusters of galaxies." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376943.
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Matthews, N. "Models of molecular line emission from star formation regions." Thesis, University of Kent, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381427.
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Bevan, Antonia. "Dust-affected models of characteristic line emission in supernovae." Thesis, University College London (University of London), 2016. http://discovery.ucl.ac.uk/1482180/.
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Galaxies and quasars in the very early universe harbour considerable masses of dust, the source of which has been much contested. For many years it was thought that core-collapse supernovae, though known to form small amounts of dust from analyses of their dust emission in the infrared, could not account for the large quantities of dust seen in the early universe. In recent years, however, this view has been challenged by the discovery of large reservoirs of cool dust in a number of supernova remnants, with some containing up to 1 Msun of dust. The late time optical and near-IR line profiles of many core-collapse supernova ejecta exhibit a red-blue asymmetry as a result of greater extinction by internal dust of radiation emitted from the receding parts of the ejecta. In this thesis, I present a new code, DAMOCLES, that models the effects of dust on the line profiles of core-collapse supernovae in order to determine the masses of newly condensed dust that have formed in the ejecta. The Monte Carlo code and the physical processes therein are described in detail and the testing of the code is presented. Theoretical profiles are produced in order to understand the effects of varying the parameters of interest on the shapes of the modelled line profiles and I discuss a number of other signatures of dust extinction on line profiles aside from the expected blue-shifting. DAMOCLES was used to model four different supernovae and supernova remnants. SN 1987A is a crucial object in the study of core-collapse supernovae and I present a detailed investigation into the rate of dust formation in this object by modelling the evolution of the Hα and [OI]λλ6300,6363Å lines. I also present models of the hydrogen and oxygen lines at late times from SN 1980K, SN 1993J and Cassiopeia A, all of which display strong blue-shifted asymmetries. I find that large dust masses are required to fit the late-time line profiles of all of these objects and conclude that core-collapse supernovae are likely an important source of dust in the universe.
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Litchfield, Simon John. "Numerical models of soft X-ray emission in accreting systems." Thesis, University of Leicester, 1992. http://hdl.handle.net/2381/35720.
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Ignace, Richard, and A. Brimeyer. "Models of Forbidden Line Emission Profiles from Axisymmetric Stellar Winds." Digital Commons @ East Tennessee State University, 2006. https://dc.etsu.edu/etsu-works/6268.
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A number of strong infrared forbidden lines have been observed in several evolved Wolf–Rayet (WR) star winds, and these are important for deriving metal abundances and testing stellar evolution models. In addition, because these optically thin lines form at large radius in the wind, their resolved profiles carry an imprint of the asymptotic structure of the wind flow. This work presents model forbidden line profile shapes formed in axisymmetric winds. It is well known that an optically thin emission line formed in a spherical wind expanding at constant velocity yields a flat-topped emission profile shape. Simulated forbidden lines are produced for a model stellar wind with an axisymmetric density distribution that treats the latitudinal ionization self-consistently and examines the influence of the ion stage on the profile shape. The resulting line profiles are symmetric about line centre. Within a given atomic species, profile shapes can vary between centrally peaked, doubly peaked, and approximately flat-topped in appearance depending on the ion stage (relative to the dominant ion) and viewing inclination. Although application to WR star winds is emphasized, the concepts are also relevant to other classes of hot stars such as luminous blue variables and Be/B[e] stars.
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Wasey, Jonathan Arthur Edward. "Spontaneous emission within wavelength-scale microstructures." Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364468.
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Honeycutt, Robert Mahone. "Acoustic emission based control of wood drying." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/39781.
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Drying is one of the most critical process steps in converting trees to a marketable material for use in high value wood products. The primary reasons for drying wood are to prevent biological deterioration and to improve mechanical strength and dimensional stability. The purpose of this research study was to develop an approach to the control of drying red oak lumber that monitors acoustic emission as the basis for setting environmental conditions throughout the drying process. Northern red oak (Quercus sp.) was chosen for this study because it is one of the more difficult woods grown in the United States to dry without inducing defects. This study was limited to end drying of short lengths of full sized red oak lumber.Ph. D.
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Westlund, Anders. "Simplified models for emission formation in diesel engines during transient operation." Doctoral thesis, KTH, Förbränningsmotorteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-33292.
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The work presented in this thesis is the result of the KTH CICERO project “Dynamic Engine Performance” in which the main objective was to develop simple models foremission formation. The demand for such models is increasing, mainly due to the tightening emission legislation for diesel engines which has lead to more complex engines and thereby more laborious development and calibration processes. Simple emission models can be a valuable tool during the development phase, e.g. when used with models for gas exchange - and after-treatment systems, and for precalibration of the engine control settings. Since engines in automotive application typically work under dynamic load, the main prerequisites were that the models should be comprehensive enough to handle the extreme conditions that can occur in engines during load transients but still simple enough to be used for calibration. Two main approaches have been used; one where the combustion and emission formation processes were modeled from the flame front and downstream using equilibrium chemistry. In the other approach, the entire mixing/entrainment process was modeled and emission formation was modeled with kinetic chemistry. Both approaches were found to meet the requirements but had different advantages; the first, simpler approach had shorter calculation time while the latter was more comprehensive and required less tuning. The latter also resulted in a model for heat release rate which can be useful as a stand-alone model and allows the emission models to be used for untested conditions. Another objective in this project was to identify techniques/instruments that can be used for emission measurements during transient operation since these are essential for understanding of emission formation in these conditions and as validation data for the emission models.QC 20110502
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Maguire, Ralph Paul. "Application of pharmacokinetic models to projection data in positron emission tomography." Thesis, University of Surrey, 1999. http://epubs.surrey.ac.uk/844467/.
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In positron emission tomography (PET), coincidence detection of annihilation photons enables the measurement of Radon transforms of the instantaneous activity concentration of labelled tracers in the human body. Using reconstruction algorithms, spatial maps of the activity distribution can be created and analysed to reveal the pharmacokinetics of the labelled tracer. This thesis considers the possibility of applying pharmacokinetic modelling to the count rate data measured by the detectors, rather than reconstructed images, A new concept is proposed - parameter projections - Radon transforms of the spatial distribution of the parameters of the model, which simplifies the problem considerably. Using this idea, a general linear least squares GLLS framework is developed and applied to the one and two tissue-compartment models for [O-15]water and [F-18]FDG. Simulation models are developed from first principles to demonstrate the accuracy of the GLLS approach to parameter estimation. This requires the validation of the whole body distribution of each of the tracers, using pharmacokinetic techniques, leading to novel compartment based whole body models for [O-15]water and [F-18]FDG. A simplified Monte-Carlo framework for error estimation of the tissue models is developed, based on system parameters. It is also shown that the variances of maps of the spatial variance of the parameters of the model - parametric images - can be calculated in projection space. It is clearly demonstrated that the precision of the variance estimates is higher than that obtained from estimates based on reconstructed images. Using the methods, it is shown how statistical parametric maps of the difference between two neuronal activation conditions can be calculated from projection data. The methods developed allow faster results analysis, avoiding lengthy reconstruction of large data sets, and allow access to robust statistical techniques for activation analysis through use of the known, Poisson distributed nature, of the measured projection data.
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Nikelski, Erwin James. "Combining positron emission tomography (PET) data with neuroanatomical constraints : comparing models of single-word processing." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26698.
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The focus of this paper is to apply some of the new analytic techniques to positron emission tomography (PET) data in order to test the neuroanatomical plausibility of two very specific models of language processing: the model of Geschwind (1965), and that of Petersen et al. (1988; 1989). Model plausibility was assessed by fitting both models to a word repetition and a synonym generation rCBF PET dataset using methods based on the examination of interregional correlations, and structural equation modeling.Physiologically-based regions of interest were defined a priori through a review of PET activation literature. The current study demonstrated (1) the feasibility of using a priori defined physiological regions of interest in model evaluation, (2) the advantages of using structural equation modeling over interregional correlations, and (3) that neither model proved to be a particularly good fit to the data.
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Ariotti, Paula. "Método para aprimorar a estimativa de emissões veiculares em áreas urbanas através de modelagem híbrida em redes." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/21922.
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Este estudo tem por objetivo propor um método para aprimorar a estimativa de emissões veiculares em áreas urbanas através da utilização de modelagem híbrida de tráfego associada a modelos de previsão de emissões. A modelagem híbrida agrega as vantagens individuais das abordagens agregada e desagregada de tráfego, uma vez que combina a micro-simulação de tráfego em áreas específicas com a simulação agregada em uma área de estudo mais abrangente. O método proposto neste trabalho foi consolidado a partir do desenvolvimento de um estudo de caso que consistiu na modelagem de uma rede viária com características distintas de infraestrutura e operação viárias. Os resultados do estudo de caso permitiram a identificação de trechos da rede viária nos quais as estimativas de emissões provenientes de modelos agregados foram significativamente diferentes das estimativas derivadas de modelos microscópicos, demonstrando a importância de uma abordagem híbrida. A utilização do método proposto pode embasar a elaboração e implementação de políticas de transportes que busquem reduzir a ocorrência de eventos responsáveis pela geração de elevados níveis de emissões.This study aims to propose a method to improve the vehicle emissions estimation in urban area. The method associates hybrid traffic flow models with emission models. Hybrid traffic modeling combines the specific advantages of aggregate and disaggregated approaches, since they integrate traffic microssimulation in specific areas with agregated simulation in a wide area. The development of the proposed method was based on a case study consisting in the modeling a road network with different operations and infrastructure characteristics. Case study results indicated that emission estimates obtained from aggregated models were significantly different from emission estimates derived from microscopic models on some road segments, emphasizing the importance of a hybrid approach adopted in the method proposed in this work. The proposed method can be used to guide the development and implementation of transportation policies that aim to reduce the number of traffic events responsible for high levels of emissions.
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Al-Awfi, Saud A. Gh. "Spontaneous emission and atom dynamics in planar and cylindrical structures." Thesis, University of Essex, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298835.
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Tang, Chia-Hsi. "Development of Satellite-Based Emission Inventories and Indoor Exposure Prediction Models for PM2.5." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:32644532.
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Epidemiological studies have documented significant relationships between outdoor particle exposure and adverse health effects whilst indoor residential PM2.5 exposure is found to be the most influential on total PM2.5 exposure as people spend more than 80% of their time indoors. Accurate exposure assessments for ambient and indoor environments are therefore of equal importance. In this dissertation, we aim to develop methodologies that enhance our ability to quantify fine particulate matter (PM2.5) exposure in both macro and micro perspective.
With advanced remote sensing technologies becoming more prevalent and less expensive, there is great potential in employing satellite date to analyze and illustrate ambient air quality in real-time over large geographic areas. In Chapter 1, we introduced a top down approach to construct PM2.5 emission inventory through the integration of mass balance and satellite retrieved daily Aerosol Optical Depth (AOD) at 1km x 1km resolution. The satellite-based inventory provides spatially- and temporally-resolved emission estimates as opposed to the conventional source-oriented inventory that has time lag issues with limited spatial variability to the extent of its data source (usually ground monitoring network). Subsequently in Chapter 2, we quantified the temporal and spatial trends of PM2.5 emission in the North East U.S. using the satellite-based emission inventory. Satellite-based emission trends are in agreement with that of the source-oriented inventories released by the US EPA, showing major reductions achieved in urban areas as well as along important traffic corridors. The technique of this part of the study can be applied to nation-wide or global remote sensing data for estimating PM2.5 emissions and hence improving the quantification of fine particles effects on climate, air quality and human health.
While big data may be the game changer for resolving ambient air quality problems, we still face the challenge of data scarcity in microenvironments. In Chapter 3, prediction models that utilize few available samples to assess indoor PM2.5 exposure were developed. We estimated infiltration rate of ambient particles penetrating indoors using sulfur as the tracer element at 95 residences in the Greater Boston Area. Mixed effects model was employed in order to predict infiltration for individual residences. We then estimate indoor levels of PM2.5 and its black carbon (BC) content using outdoor measurements and the estimated infiltration factor. We cross validated the aforementioned models to evaluate their predictive power specifically at dates without indoor information. Cross validation results of the infiltration model (R2=0.89) indicates that mixed effects captured infiltration rates for individual households adequately. We also found strong predictability when sulfur infiltration surrogate and outdoor measurements of PM2.5 and BC were used in predicting indoor exposure levels (R2= 0.79 [PM2.5], 0.76 [BC]).
Altogether, the methodologies introduced in this dissertation may serve as frameworks to (1) quantify and illustrate ambient emission of PM2.5 or other pollutants in a macro perspective and (2) determine the relationships between outdoor and indoor air quality and to predict indoor air pollution which are critical information for developing solutions of micro-level air quality problems.
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CLOUGH, ANNE VIRGINIA. "A MATHEMATICAL MODEL OF SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY (RADON TRANSFORM, COMPTON SCATTER, ATTENUATION, NUCLEAR MEDICINE)." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/188142.
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Single-photon emission computed tomography (SPECT) is a nuclear-medicine imaging technique that has been shown to provide clinically useful images of radionuclide distributions within the body. The problem of quantitative determination of tomographic activity images from a projection data set leads to a mathematical inverse problem which is formulated as an integral equation. The solution of this problem then depends on an accurate mathematical model as well as a reliable and efficient inversion algorithm. The effects of attenuation and Compton scatter within the body have been incorporated into the model in the hopes of providing a more physically realistic mathematical model. The attenuated Radon transform is the mathematical basis of SPECT. In this work, the case of constant attenuation is reviewed and a new proof of the Tretiak-Metz algorithm is presented. A space-domain version of the inverse attenuated Radon transform is derived. A special case of this transform that is applicable when the object is rotationally symmetric, the attenuated Abel transform is derived, and its inverse is found. A numerical algorithm for the implementation of the inverse attenuated Radon transform with constant attenuation is described and computer simulations are performed to demonstrate the results of the inversion procedure. With the use of the single-scatter approximation and an energy-windowed detector, the effects of Compton scatter are incorporated into the model. The data is then taken to be the sum of primary photons and single-scattered photons. The scattered photons are modeled by a scatter operator acting on the original activity distribution within the object where the operator consists of convolution with a given analytic kernel followed by a boundary cut-off operation. A solution is given by first applying the inverse attenuated Radon transform to the data set. This leads to a Fredholm integral equation to which a Neumann series solution is constructed. Again simulations are performed to validate the accuracy of the assumptions within the model as well as to numerically demonstrate the reconstruction procedure.
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Ramanujan, Abhishek. "Development of automated frequency and time-domain radiated electromagnetic emission models for microelectronic applications." Rouen, 2011. http://www.theses.fr/2011ROUES043.
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La compatibilité électromagnétique (CEM) des composants électroniques est devenue indispensable pour la conception des systèmes embarqués microélectroniques. Les modèles CEM aident les concepteurs de circuits à comprendre le comportement du système avant même sa fabrication. Dans ce contexte, un modèle électromagnétique générique des émissions rayonnées, optimisé et compatible avec la modélisation des dispositifs microélectroniques miniatures a été développé. L’architecture de base de ce modèle a été inspirée du modèle du champ magnétique développé antérieurement à l’IRSEEM. Dans un premier temps un modèle mono-fréquence capable de reproduire et de prévoir le champ électromagnétique rayonné au-dessus d’un dispositif électronique sous test a été développé. Un réseau de dipôles électriques élémentaires associé à une nouvelle méthode d’extraction incorporant un algorithme d’optimisation non-linéaire, sont mis en oeuvre. Le rôle de la permittivité relative du dispositif sous test est pris en compte dans la procédure de modélisation. Le modèle a été validé sur plusieurs composants micro-ondes classiques, miniatures et circuits « on-chip ». L’optimisation mathématique du modèle l’a rendu plus robuste et par conséquent applicable aux dispositifs complexes. Le nouveau concept a été validé sur deux cas de test. Deuxièmement, le modèle mono-fréquence a été étendu afin de prédire le champ électromagnétique large-bande et, par conséquent, le champ dans le domaine temporel. La méthode de série de Fourier est utilisée pour transférer les données du domaine fréquentiel vers le domaine temporel. Le principe de modélisation a été validé par des simulations effectuées avec un logiciel électromagnétique 3D. Enfin, un environnement convivial de modélisation (outil) a été développéWith component level electromagnetic compatibility (EMC) taking the front stage in design of embedded microelectronic systems, EMC models help circuit designers in understanding the behavior of the system even before its fabrication. In this context, generic electromagnetic emission models, optimized and compatible to modeling miniature microelectronic devices, are developed. The basic architecture of the models has been inspired from a previously existing magnetic field model developed in IRSEEM. First, a mono-frequency model capable of reproducing and predicting the radiated electromagnetic fields above any device is developed. A set of elementary electric dipole is used to represent the model and a state-of-the art extraction method, incorporating a non-linear optimization algorithm, is implemented in order to extract the model parameters. The role of the effective relative permittivity of the DUT is taken into account in the modeling procedure. The model has been validated on several conventional microwave components, miniature and “on-chip” devices. The computational performance of the model is then optimized and made robust suitable for application to complex devices. As a proof of concept, the method is validated on a couple of test cases. Second, the monofrequency model is extended toward predicting the large-band electromagnetic fields and thereby the time-harmonic fields. Fourier series based method is used for transforming the wide-band frequency data into time-domain. The modeling principle is validated with time-domain simulations performed in a 3D electromagnetic software. Finally, an integrated development environment has been developed in order to facilitate the use of the developed emission models. The menu-based intuitive tool provides the right environment for engineers and designers to use and test the models for specialized applications
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Priston, Ann-Marie. "Evaluation of stress induced damage in composite material." Thesis, Nottingham Trent University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389766.
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Olshen, Adam B. "Modeling PET blood curves /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/9530.
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Aryal, Bijaya. "Transfer of learning with an application to the physics of positron emission tomography." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/351.
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Hodge, Duncan. "Deformation of 113Cs from proton-emission and electromagnetic transition rates." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/deformation-of-113cs-from-protonemission-and-electromagnetic-transition-rates(4120984a-29b6-498c-8f05-2fe1946fd661).html.
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Studying nuclei beyond the proton dripline can provide valuable information on the structure of nuclei at the limits of stability, where the strong nuclear force starts to be overcome by Coulomb repulsion between protons. Simple experimental observables, such as excitation energies and lifetimes of excited states in these proton-unbound nuclei can provide information on the nuclear wave function. Experimental data, such as that presented in this work, can then be used to improve models of nuclear structure at the proton dripline. This thesis presents data from a recoil-decay tagged differential plunger experiment undertaken at the University of Jyvaskyla in 2014. A fusion-evaporation reaction was used to populate excited states in the deformed ground-state proton emitter 113Cs. The JUROGAM-RITU-GREAT experimental setup was used to correlate gamma rays emitted from these excited states with protons emitted from 113Cs and the differential plunger for unbound nuclear states (DPUNS) was placed at the target position to measure the excited state lifetimes. The lifetime of the (11/2+) state in the most intense rotational band of 113Cs was measured to be tau = 24(6) ps, while a limit of tau is less than or equal to 5 ps was found for the lifetime of the higher energy (15/2+) state. The lifetime of proton emission was measured to be tau = 24.2(2) microseconds. The experimental data were used to test the predictions of a non adiabatic quasi-particle model for proton-emitting nuclei, which was employed to deduce the deformation of the states in 113Cs. Wave functions from the non adiabatic quasi-particle model were used to independently calculate proton-emission rates, gamma-ray transition rates and excited state energies as functions of deformation. The deformation of 113Cs could then be extracted from the intersection of the different theoretical values and experimental observables. A deformation of beta2 = 0.22(6)was extracted from the (11/2+) excitation energy and lifetime. The deformation values taken from the proton-emission rate and the lifetime limit of the (15/2+) state were also consistent with this value. The consistency of the different deformations calculated shows the effectiveness of the non adiabatic quasi-particle method when used to calculate the properties of deformed ground-state proton-emitters.
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Nikelski, Erwin James. "Combining positron emission tomography, PET, data with neuroanatomical constraints, comparing models of single-word processing." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0016/MQ29504.pdf.
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Jovkar, Sayed. "Optimization of experimental design in Tracer kinetic models applied to Positron Emission Tomography and Autordiography." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65387.
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Tsoumpas, Charalampos. "Direct statistical parametric image estimation for linear pharmacokinetic models form quantitative position emission tomography measurements." Thesis, Imperial College London, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.535000.
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McPherson, Jr Michael Gene. "Microbial interactions, B cell immunoregulation , and positron emission detection in murine models of intestinal inflammation." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1580937001&sid=1&Fmt=2&clientId=48051&RQT=309&VName=PQD.
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Gomes, Ruben José Silva. "Estudo do Impacte de uma Zona de Emissões Reduzidas em Coimbra." Master's thesis, [do autor], 2016. http://hdl.handle.net/10316/88813.
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Dissertação de Mestrado em Engenharia do Ambiente apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.Apesar de ter melhorado a qualidade do ar em áreas urbanas nas últimas décadas, os níveis de poluição ainda continuam elevadas, causando impactos negativos na saúde humana. As emissões de poluentes do tráfego rodoviário são umas das principais razões pela degradação da qualidade do ar nas áreas urbanas. Assim, cada vez mais se tem implementado medidas com o objetivo de promover melhorias na qualidade do ar. O objetivo desta dissertação consistiu na avaliação do impacte na qualidade do ar esperado numa área urbana com a introdução de uma potencial Zona de Emissões. Para este estudo foi necessário recorrer a dois tipos de modelos. Inicialmente recorreu-se a um modelo de emissões, QTraffic, desenvolvido na Universidade de Coimbra, no qual permitiu estimar as emissões do tráfego rodoviário. Por último, utilizou-se um modelo de qualidade do ar, ADMS-Roads, para a caraterização da dispersão de poluentes. A metodologia foi aplicada à área urbana de Coimbra, mais propriamente à zona de proteção e ao património mundial. Com base nos resultados obtidos foi possível avaliar o impacte na qualidade do ar esperada com a introdução de uma Zona de Emissões Reduzidas. Constatou-se que haveria reduções nas emissões de PM10 (61%), NOx (42%) e NO2 (22%), servindo como um bom indicar na melhoria da qualidade do ar. Quanto aos resultados do modelo de qualidade do ar, ficou claro que seria de esperar melhorias na qualidade do ar com reduções máximas nas concentrações médias anuais de PM10 (1,23 μg/m3) e de NO2 (4,41 μg/m3) mas contudo, seria de esperar um impacte negativo no caso de O3. Este trabalho pretende contribuir para um melhor entendimento do impacte potencial na qualidade do ar com a aplicação de uma Zona de Emissões Reduzidas e avaliar qual seria o benefício caso uma medida deste tipo fosse aplicada à área urbana de Coimbra.
Despite improving air quality in urban areas in recent decades, pollution levels still remain high, causing negative impacts on human health. The road traffic pollutants emissions are one of the main reasons for the degradation of air quality in urban areas. So, increasingly we have implemented measures in order to promote improvements in air quality. The objective of this work was the impact assessment on air quality expected in an urban area with the introduction of a potential Emission Zone. For this study it was necessary to use two types of models. Initially resorted to an emissions model, QTraffic, developed at the University of Coimbra, which allowed us to estimate emissions from road traffic. Finally, we used a model of quality of air, ADMS-Roads, enabling to characterize the dispersion of pollutants. The methodology was applied to the urban area of Coimbra, more specifically the protection zone and the world heritage. Based on the results it was possible to assess the impact on the quality of air expected with the introduction of a Reduced Emissions Zone. It was found that there would be reductions in emissions of PM10 (61%), NOx (42%) and NO2 (22%), serving as a state in improving air quality. As for the results of the air quality model, it became clear that expected maximum reductions in the annual average concentrations of PM10 (1.23 μg/m3) and NO2 (4.41 μg/m3) but however, would expect a negative impact in the case of O3. This work aims to contribute to a better understanding of the potential impact on air quality with the implementation of a Reduced Emissions Zone and evaluate what would be the benefit if such a measure were applied to the urban area of Coimbra.
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Smit, Robin, and n/a. "An Examination of Congestion in Road Traffic Emission Models and Their Application to Urban Road Networks." Griffith University. School of Environmental Science, 2007. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070724.155421.
Full textAbstract:
The level of air pollution in urban areas, which is largely affected by road traffic, is an issue of high political relevance. Congestion is most prevalent in urban areas and a common and increasingly present phenomenon worldwide. The first four chapters of this study have investigated how and to what extent models, which are used to predict emissions on road links in urban road networks, include the effects of congestion on emissions. In order to make this assessment, traffic engineering literature and empirical studies have been examined and used as a basis to review (current) emission models that exist or have been used around the world. Congestion causes changes in driving patterns of individual vehicles in a traffic stream, and these changes are subsequently reflected in changes in congestion indicators and changes in emission levels. This consideration and a literature review has led to a proposed 'congestion typology' of emission models, which reflects the different ways in which and the extent to which congestion has been incorporated in these models. The typology clarifies that six of in total ten families of emission models that were investigated in this thesis explicitly consider congestion in the modelling process (i.e. model variables are related to congestion), although this is done in different ways. For the remaining four families of emission models it was not possible to determine the extent to which congestion has been incorporated on the basis of literature review alone. Two families fell beyond the scope of this work since they cannot be used to predict emission on road links. For the other two families it became clear in the course of the thesis that the extent can be determined through analysis of driving pattern data (and other information with respect to e.g. data collection) that were used in the model development. A new methodology is presented in this thesis to perform this analysis and to assess the mean level of congestion in driving patterns (driving cycles). The analysis has been carried out for one important family of emission models, the so-called travel speed models ('average speed models'), which are used extensively in urban network modelling. For four current models (COPERT III, MOBILE 6, QGEPA 2002, EMFAC 2000), it is concluded that these models implicitly (i.e. congestion is inherently considered) take varying levels of congestion into account, but that this conclusion is subject to a number of limitations. It became clear in the course of this study that prediction of (the effects of) congestion in both traffic models and emission models is generally restricted to certain modelling dimensions. As a consequence, the effects of congestion are only partially predicted in current air emission modelling. Chapter 5 has attempted to address the question whether congestion is actually an important issue in urban network emission modelling or not. It also addressed the question if different types of emission models actually predict different results. On the basis of a number of selection criteria, two types of models were compared, i.e. one explicit model (TEE-KCF 2002) and two implicit models (COPERT III, QGEPA 2002). The research objectives have been addressed by applying these emission models to a case-study urban network in Australia (Brisbane) for which various model input attributes were collected from different sources (both modelled and field data). The findings are limited by the fact that they follow from one urban network with particular characteristics (fleet composition, signal settings, speed limits) and application of only a few particular emission models. The results therefore indicate that: 1. Changes in traffic activity (i.e. distribution of vehicle kilometres travelled on network links) over the day appear to have the largest effect on predicted traffic emissions. 2. Congestion is an important issue in the modelling of CO and HC emissions. This appears not to be the case for NOx emissions, where basic traffic composition is generally a more important factor. For the most congested parts in the urban network that have been investigated, congestion can more than double predicted emissions of CO and HC. 3. Different types of emission models can produce substantially different results when absolute (arithmetic) differences are considered, but can produce similar results when relative differences (ratio or percent difference) are considered.
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Smit, Robin. "An Examination of Congestion in Road Traffic Emission Models and Their Application to Urban Road Networks." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/365194.
Full textAbstract:
The level of air pollution in urban areas, which is largely affected by road traffic, is an issue of high political relevance. Congestion is most prevalent in urban areas and a common and increasingly present phenomenon worldwide. The first four chapters of this study have investigated how and to what extent models, which are used to predict emissions on road links in urban road networks, include the effects of congestion on emissions. In order to make this assessment, traffic engineering literature and empirical studies have been examined and used as a basis to review (current) emission models that exist or have been used around the world. Congestion causes changes in driving patterns of individual vehicles in a traffic stream, and these changes are subsequently reflected in changes in congestion indicators and changes in emission levels. This consideration and a literature review has led to a proposed 'congestion typology' of emission models, which reflects the different ways in which and the extent to which congestion has been incorporated in these models. The typology clarifies that six of in total ten families of emission models that were investigated in this thesis explicitly consider congestion in the modelling process (i.e. model variables are related to congestion), although this is done in different ways. For the remaining four families of emission models it was not possible to determine the extent to which congestion has been incorporated on the basis of literature review alone. Two families fell beyond the scope of this work since they cannot be used to predict emission on road links. For the other two families it became clear in the course of the thesis that the extent can be determined through analysis of driving pattern data (and other information with respect to e.g. data collection) that were used in the model development. A new methodology is presented in this thesis to perform this analysis and to assess the mean level of congestion in driving patterns (driving cycles). The analysis has been carried out for one important family of emission models, the so-called travel speed models ('average speed models'), which are used extensively in urban network modelling. For four current models (COPERT III, MOBILE 6, QGEPA 2002, EMFAC 2000), it is concluded that these models implicitly (i.e. congestion is inherently considered) take varying levels of congestion into account, but that this conclusion is subject to a number of limitations. It became clear in the course of this study that prediction of (the effects of) congestion in both traffic models and emission models is generally restricted to certain modelling dimensions. As a consequence, the effects of congestion are only partially predicted in current air emission modelling. Chapter 5 has attempted to address the question whether congestion is actually an important issue in urban network emission modelling or not. It also addressed the question if different types of emission models actually predict different results. On the basis of a number of selection criteria, two types of models were compared, i.e. one explicit model (TEE-KCF 2002) and two implicit models (COPERT III, QGEPA 2002). The research objectives have been addressed by applying these emission models to a case-study urban network in Australia (Brisbane) for which various model input attributes were collected from different sources (both modelled and field data). The findings are limited by the fact that they follow from one urban network with particular characteristics (fleet composition, signal settings, speed limits) and application of only a few particular emission models. The results therefore indicate that: 1. Changes in traffic activity (i.e. distribution of vehicle kilometres travelled on network links) over the day appear to have the largest effect on predicted traffic emissions. 2. Congestion is an important issue in the modelling of CO and HC emissions. This appears not to be the case for NOx emissions, where basic traffic composition is generally a more important factor. For the most congested parts in the urban network that have been investigated, congestion can more than double predicted emissions of CO and HC. 3. Different types of emission models can produce substantially different results when absolute (arithmetic) differences are considered, but can produce similar results when relative differences (ratio or percent difference) are considered.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental Planning
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Pant, Gaurav. "Hybrid Dynamic Modelling of Engine Emissions on Multi-Physics Simulation Platform. A Framework Combining Dynamic and Statistical Modelling to Develop Surrogate Models of System of Internal Combustion Engine for Emission Modelling." Thesis, University of Bradford, 2018. http://hdl.handle.net/10454/17223.
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Park, Sangjun. "Developing Procedures for Screening High Emitting Vehicles and Quantifying the Environmental Impacts of Grades." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/46178.
Full textAbstract:
Since the transportation sector is highly responsible for U.S. fuel consumption and emissions, assessing the environmental impacts of transportation activities is essential for air-quality improvement programs. Also, high emitting vehicles need to be considered in the modeling of mobile-source emissions, because they contribute to a large portion of the total emissions, although they comprise a small portion of the vehicle fleet. In the context of this research, the thesis quantifies the environmental impacts of roadway grades and proposes a procedure that can enhance the screening of high emitting vehicles.
First, the study quantifies the environmental impacts of roadway grades. Although roadway grades are known to affect vehicle fuel consumption and emission rates, there do not appear to be any systematic evaluations of these impacts in the literature. Consequently, this study addresses this void by offering a systematic analysis of the impact of roadway grades on vehicle fuel consumption and emission rates using the INTEGRATION microscopic traffic simulation software. The energy and emission impacts are quantified for various cruising speeds, under stop and go conditions, and for various traffic signal control scenarios. The study demonstrates that the impact of roadway grade is significant with increases in fuel consumption and emission rates in excess of 9% for a 1% increase in roadway grade. Consequently, a reduction in roadway grades in the range of 1% can offer savings that are equivalent to various forms of advanced traffic management systems.
Second, the study proposes a new procedure for estimating vehicle mass emissions from remote sensing device measurements that can be used to enhance HEV screening procedures. Remote Sensing Devices (RSDs) are used as supplementary tools for screening high emitting vehicles (HEVs) in the U.S. in order to achieve the National Ambient Air Quality Standards (NAAQS). However, tailpipe emissions in grams cannot be directly measured using RSDs because they use a concentration-based technique. Therefore, converting a concentration measurement to mass emissions is needed. The research combines the carbon balance equation with fuel consumption estimates to make the conversion. In estimating vehicle fuel consumption rates, the VT-Micro model and a Vehicle Specific Power (VSP)-based model (the PERE model) are considered and compared. The results of the comparison demonstrate that the VSP-based model under-estimates fuel consumption at 79% and produces significant errors (R2 = 45%), while the VT-Micro model produces a minimum systematic error of 1% and a high degree of correlation (R2 = 87%) in estimating a sample vehicle's (1993 Honda Accord with a 2.4L engine) fuel consumption. The sample vehicle was correctly identified 100%, 97%, and 89% as a normal vehicle in terms of HC, CO, NOX emissions, respectively, using its in-laboratory measured emissions. Its estimated emissions yielded 100%, 97%, and 88% of correct detection rates in terms of HC, CO, NOX emissions, respectively. The study clearly demonstrates that the proposed procedure works well in converting concentration measurements to mass emissions and can be applicable in the screening of HEVs and normal emitting vehicles for several vehicle types such as sedans, station wagons, full-size vans, mini vans, pickup trucks, and SUVs.Master of Science
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Park, Sangjun. "High Automobile Emissions: Modeling Impacts and Developing Solutions." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/28918.
Full textAbstract:
In the last few years, scientific consensus is that emission of greenhouse gases (GHGs) into the atmosphere is contributing to changes in the earth's climate. While uncertainty remains over the pace and dimensions of the change, a consensus on the need for action has grown among the public and elected officials. In part, this shift has been accelerated by concern over energy security and rising fuel prices. The new political landscape has led many cities, states, and regions to institute policies aimed at reducing GHG emissions. These policies and emerging initiatives have significant implications for the transportation planning process. The transportation sector accounts for approximately 27% of GHG production in the U.S. (as of 2003) and while the U.S. accounts for only roughly 5% of the world's population, it is estimated that it produces over 20% of the world's GHG emissions. Note that this does not include "lifecycle" emissions that result from the processes undertaken to extract, manufacture, and transport fuel. Carbon dioxide represents approximately 96% of the transportation sector's radiative forcing effects. Unlike conventional air pollutants, carbon dioxide emissions are directly tied to the amount of fuel consumed and its carbon intensity. Therefore, emissions reductions can be achieved by increasing the use of low-carbon fuels, improving fuel economy, or reducing total vehicle miles of travel - often called the three legged stool. (A fourth leg is congestion reduction, at certain optimal speeds). These same factors are related to our use of imported oil, so actions taken to reduce GHG emissions may actually produce benefits in both policy areas. The climatic risks of additional emissions associated with capacity projects must be balanced against the mobility, safety, and economic needs of a community or region. Consequently, this dissertation attempts to quantify the impacts of high-emitting vehicles on the environment and to propose solutions to enhance the currently-used high-emitting vehicle detection procedures. In addition, fuel consumption and emission models for high-speed vehicles are developed in order to provide more reliable estimates of vehicle emissions and study the impact of vehicle speeds on vehicle emissions.
The dissertation extends the state-of-the-art analysis of high emitting vehicles (HEVs) by quantifying the network-wide environmental impact of HEVs. The literature reports that 7% to 12% of HEVs account for somewhere between 41% to 63% of the total CO emissions, and 10% are responsible for 47% to 65% of HC emissions, and 10% are responsible for 32% of NOx emissions. These studies, however, are based on spot measurements and do not necessarily reflect network-wide impacts. Consequently, the research presented in this dissertation extends the state-of-knowledge by quantifying HEV contributions on a network level. The study uses microscopic vehicle emission models (CMEM and VT-Micro model) along with pre-defined drive cycles (under the assumption that the composite HEV and VT-LDV3 represent HEVs and NEVs, respectively) in addition to the simulation of two transportation networks (freeway and arterial) to quantify the contributions of HEVs. The study demonstrates that HEVs are responsible for 67% to 87% of HC emissions, 51% to 78% of CO emissions, and 32% to 62% of the NOX emissions for HEV percentages ranging from 5% to 20%. Additionally, the traffic simulation results demonstrate that 10% of the HEVs are responsible for 50% to 66% of the I-81 HC and 59% to 78% of the Columbia Pike HC emissions, 35% to 67% of the I-81 CO and 38% to 69% of the Columbia Pike CO emissions, and 35% to 44% of the I-81 NOX and 35% to 60% of the Columbia Pike NOX emissions depending on the percentage of the normal-emitting LDTs to the total NEVs. HEV emission contributions to total HC and CO emissions appear to be consistent with what is reported in the literature. However, the contribution of NOX emissions is greater than what is reported in the literature. The study demonstrates that the contribution of HEVs to the total vehicle emissions is dependent on the type of roadway facility (arterials vs. highways), the background normal vehicle composition, and the composition of HEVs. Consequently, these results are network and roadway specific. Finally, considering that emission control technologies in new vehicles are advancing, the contribution of HEVs will increase given that the background emission contribution will decrease.
Given that HEVs are responsible for a large portion of on-road vehicle emissions, the dissertation proposes solutions to the HEV screening procedures. First, a new approach is proposed for estimating vehicle mass emissions from concentration remote sensing emission measurements using the carbon balance equation in conjunction with either the VT-Micro or PERE fuel consumption rates for the enhancement of current state-of-the-art HEV screening procedures using RSD technology. The study demonstrates that the proposed approach produces reliable mass emission estimates for different vehicle types including sedans, station wagons, full size vans, mini vans, pickup trucks, and SUVs. Second, a procedure is proposed for constructing on-road RS emission standards sensitive to vehicle speed and acceleration levels. The proposed procedure is broadly divided into three sub-processes. In the first process, HE cut points in grams per second are developed as a function of a vehicle's speed and acceleration levels using the VT-Micro and CMEM emission models. Subsequently, the HE cut points in grams per second are converted to concentration emissions cut points in parts per million using the carbon balance equation. Finally, the scale factors are computed using either ASM ETW- and model-year-based standards or engine-displacement-based standards. Given the RS emissions standards, the study demonstrated that the use of on-road RS cut points sensitive to speed and acceleration levels is required in order to enhance the effectiveness of RS.
Finally, the dissertation conducted a study to develop fuel consumption and emissions models for high-speed vehicles to overcome the shortcomings of state-of-practice models. The research effort gathered field data and developed models for the estimation of fuel consumption, CO₂, CO, NO, NO2, NOx, HC, and PM emissions at high speeds. A total of nine vehicles including three semi-trucks, three pick-up trucks, and three passenger cars were tested on a nine-mile test track in Pecos, Texas. The fuel consumption and emission rates were measured using two portable emission measurement systems. Models were developed using these data producing minimum errors for fuel consumption, CO₂, NO2, HC, and PM emissions. Alternatively, the NO and NOx emission models produced the highest errors with a least degree of correlation. Given the models, the study demonstrated that the newly constructed models overcome the shortcomings of the state-of-practice models and can be utilized to evaluate the environmental impacts of high speed driving.Ph. D.
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Alanezi, Salwa. "Emission inventories from Kuwait petroleum refineries and respective ground level concentration of pollutants in the neighboring residential area." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/12544.
Full textAbstract:
The State of Kuwait has three large refineries, namely, Mina Al Ahmadi Refinery, Mina Abdullah Refinery and Shuaiba Refinery. These refineries process and refine Kuwait Crude Oil through different process units. There are many heaters, boilers and flares that form a part of the complicated equipment which enhance the different petroleum processes. Fuel gas is used as a firing fuel for those heaters and boilers. As a result, stack emissions like SO2, NOx, CO are predominantly present in the flue gases and this study focuses on those emissions and their impact on the surrounding residential area. The area of interest will be Umm Al-Hyman residential area. This study accumulates emission inventories from the three refineries and the respective ground level concentration of the pollutants in the neighboring residential area. It also focuses on the impact of emissions from the refinery operations on the ground level concentrations in the surrounding areas by using the inventory model and latest emission factors to provide accurate emission estimates. The models were developed and the results were verified with the actual data from the area of impact. As a result of the findings of the major pollutants, namely SO2, NOx & CO, it is found that SO2 and CO are not exceeding Kuwait EPA Ambient Air Quality Standards for Residential Areas normally. However, NOx is observed to exceed occasionally. Even though, NOx emissions from refineries sources represented by plume models were much less, there is a consistent increase in the measured NOx. Furthermore, in 2007, the measured hourly, daily and annual NOx concentration exceeded the international standard many times. The increasing trend in NOx is attributed to continuous increase in population and the number of motor vehicles. The study will go further step in recommending engineering solutions and best practices to reduce the pollutants concentrations which will help in the reduction of human health risks and protect the environment.
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Chaney, Aisling. "Investigating imaging biomarkers of neuroinflammation and neurodegeneration in rodent models of Alzheimer's disease." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/investigating-imaging-biomarkers-of-neuroinflammation-and-neurodegeneration-in-rodent-models-of-alzheimers-disease(16750cf1-eb30-49c5-b9eb-9f01d4a0560f).html.
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Alzheimer’s disease (AD) is a progressive neurodegenerative disease resulting in alterations in memory, language, executive function and emotional behaviour. Although it can be characterised by symptoms, by the time they arise significant pathological alterations have already emerged in the central nervous system, namely increased amyloid plaques, neurofibrillary tangles and neuronal loss. Despite known pathological hallmarks the exact aetiology of AD is poorly understood and no current treatments are available. However, there is growing interest in the role of neuroinflammation in AD, with increases observed in the early stages of disease and with disease progression. Moreover, it has been suggested that peripheral inflammation can influence neuroinflammation and worsen neurodegeneration. Using Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRS) we can non-invasively measure biomarkers of neuroinflammation and degeneration allowing multi-modal investigation of its role in normal aging and AD. Considering this the objectives of this study were to (i) Use PET and MRS to investigate neuroinflammatory and metabolite alterations in transgenic (TG) models of AD and their wildtype (WT) animals. (ii) Assess rates of cognitive decline in these models using memory based tests. (iii) Investigate relatively new TgF344AD rat as an AD model by characterising younger time-points than previously reported. (iv) Investigate the contribution of peripheral inflammation on AD progression. PET and MRS imaging was carried out longitudinally in the APPswe×PS1de9 mouse. Neuroinflammation was confirmed ex vivo and cognitive ability was assessed by behavioural tests. Results revealed significantly increase hippocampal and thalamic neuoinflammation in old TG mice as assessed by [18F]DPA-714 PET and supported by immunohistochemistry. Reduced neuronal marker N-acetlyaspartate was seen with age and was exacerbated in the TG mice. Accelerated cognitive decline was also seen in TG mice. PET and MRS imaging was carried out at 6 and 12 months in the TgF344AD model, which expresses amyloid and tau pathology as well as neuronal loss. No cognitive decline was observed in TG rats; however increased anxiety behaviour was seen. Increased [18F]DPA-714 PET was observed as an effect of gene in the thalamus at 6 months and the hypothalamus at 12 months. Increases in glutamate were seen with age in the TG rats but not the WTs. Increased inflammation and metabolite alterations were seen with aging. The effect of peripheral urinary tract infection (UTI) on cognition and imaging out was assessed. Imaging was carried out prior to and after re-current UTI. Infection induced cognitive decline in infected TG but not WT rats. Infection had an increasing effect on hypothalamic neuroinflammation in WT rats but a decreasing effect on TG rats, which masked the original gene differences. This thesis is set out in the alternative format with each experimental study represented as a chapter. Results in this thesis implicate neuroinflammation in AD development and progression. In addition, we report systemic infection-CNS interactions accelerating cognitive decline in AD and highlight the importance of understanding the effects of comorbidities in disease.
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Powell, James Eckhardt. "Building a Multivariable Linear Regression Model of On-road Traffic for Creation of High Resolution Emission Inventories." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3415.
Full textAbstract:
Emissions inventories are an important tool, often built by governments, and used to manage emissions. To build an inventory of urban CO2 emissions and other fossil fuel combustion products in the urban atmosphere, an inventory of on-road traffic is required. In particular, a high resolution inventory is necessary to capture the local characteristics of transport emissions. These emissions vary widely due to the local nature of the fleet, fuel, and roads.
Here we show a new model of ADT for the Portland, OR metropolitan region. The backbone is traffic counter recordings made by the Portland Bureau of Transportation at 7,767 sites over 21 years (1986-2006), augmented with PORTAL (The Portland Regional Transportation Archive Listing) freeway traffic count data. We constructed a regression model to fill in traffic network gaps using GIS data such as road class and population density. An EPA-supplied emissions factor was used to estimate transportation CO2 emissions, which is compared to several other estimates for the city's CO2 footprint.
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Sridharan, Sujata. "Quantitative analysis of positron emission tomography (PET) with the second generation translocator protein (TSPO) ligand [18F]GE-180." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/quantitative-analysis-of-positron-emission-tomography-pet-with-the-second-generation-translocator-protein-tspo-ligand-18fge180(01bdc97f-90f7-4db3-8268-f65e013640ab).html.
Full textAbstract:
Background: The 18 kDa translocator protein (TSPO), expressed at a low level in the healthy human central nervous system (CNS), is upregulated in inflammatory brain diseases by activated microglia and other immune cells. Using positron emission tomography (PET) radioligands targeting TSPO, it is possible to localise this signal and map the course of microglial activation and its effects on disease progression. Here, a newly developed second generation TSPO PET ligand, [18F]GE-180, was evaluated in different models of preclinical and clinical neuroinflammatory disease. Methods: A preclinical model of low-level inflammation with lipopolysaccharide (LPS) was designed. Rats were scanned with the first generation TSPO ligand [11C]- (R)-PK11195 and either [18F]GE-180 or [18F]DPA-714, with dual scanning enabling the direct comparison of second generation tracers with [11C]-(R)-PK11195. An arterial blood sampling system for rodent imaging with [18F]DPA-714 was set up and characterised. The performance of [18F]GE-180 was assessed in a clinical study in nine relapsing-remitting multiple sclerosis patients (RRMS) and ten healthy volunteers (HV). A comparison of kinetic modelling approaches for [18F]GE-180 human brain PET data was performed, as well as a longitudinal analysis with intervention using the disease-modifying treatment, natalizumab to evaluate the potential of [18F]GE-180 as a biomarker for therapy monitoring in MS subjects. Finally, the plasma-protein binding behaviour of [18F]GE-180 was evaluated in vitro using ultrafiltration. Results: In LPS animals, [18F]GE-180 produced a significantly higher ipsi- to contralateral uptake ratio and binding potential () than [11C]-(R)-PK11195 (p = 0.03), but [18F]DPA-714 did not. There was no significant difference between animals scanned with [18F]GE-180 and [18F]DPA-714, suggesting no overall superiority of the former. Characterisation of an arterial sampling system for rodent studies with [18F]DPA-714 allowed correction for dispersion effects. A comparison of reference regions showed that a novel externally derived tissue estimated with lower bias than a contralateral reference region. In human [18F]GE-180 brain PET data, the unconstrained two-tissue compartment model (2TCM) best described tracer behaviour in RRMS and HV subjects. Normal appearing white matter (NAWM) in patients was elevated over that of HVs. Standardised uptake values (SUVs) for the tracer in rodents were 0.28±0.12 and 0.84±0.31 in healthy tissue and LPS lesions respectively, and in humans were 0.36±0.04 (HV) and 0.58 (in a gadolinium- enhancing MS lesion). [18F]GE-180 uptake was also significantly reduced in the brains of RRMS subjects treated with natalizumab, correlating with clinically-identified improvement. [18F]GE-180 has a free fraction of between 1 and 8%.Conclusions: [18F]GE-180 shows good brain uptake in the rodent brain and produces superior signal to [11C]-(R)-PK11195, but not to [18F]DPA-714. The 2TCM fits human [18F]GE-180 PET data well, and the tracer is able to identify an elevated signal in RRMS patients compared to healthy subjects. [18F]GE-180 shows a large fraction of non-displaceable binding in human blood, thus further optimisation of kinetic modelling approaches is suggested.
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Roberts, Craig Arnold. "Modeling the relationships between microscopic and macroscopic travel activity on freeways : bridging the gap between current travel demand models and emerging mobile emission models." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/32873.
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Jones, Derek. "Evaluation of Arrayed-Field Concentration Measurements and U. S. EPA-Regulatory Models for the Determination of Mixed-source Particulate Matter Emissions." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/156.
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With the continued population growth and the blurring of the urban and rural interface, air quality impacts associated with agricultural particle-producing processes are becoming increasingly important. There is a lack of emission rate data from these source types and no prescribed measurement technique available to the agricultural and regulatory communities. One technique that has shown promise is combining field measurements with inverse modeling. This approach was used herein to examine particulate emissions from an almond harvesting operation, a cotton ginning facility, and comparative emissions from conservation versus conventional tillage practices. EPAapproved models ISCST3 and AERMOD were used with AirMetrics samplers. With error representing the standard deviation for all values, for ISCST3, the almond harvesting operation found PM10 emissions for shaking were 3.4 kilograms per hectare; PM2.5, PM10, and TSP emissions for sweeping were 0.81 ± 0.76, 4.8 ± 3.7, and 7.5 ± 5.1 kg ha-1, respectively; PM2.5, PM10, and TSP emissions for pickup were 1.7 ± 1.5, 6.1 ± iii 1.9, and 10.3 ± 3.8 kg ha-1, respectively. Using AERMOD, the almond harvesting operation found PM10 emissions for shaking were 4.4 kg ha-1; PM2.5, PM10, and TSP emissions for sweeping were 1.3 ± 1.5, 8.3 ± 9.4, and 27.0 ± 41.2 kg ha-1, respectively; PM2.5, PM10, and TSP emissions for pickup were 2.7 ± 1.3, 15.7 ± 14.1, and 42.3 ± 20.7 kg ha-1, respectively. PM2.5, PM10, and TSP emissions from the cotton gin were determined to be 1.7 ± 1.4, 14.3 ± 17.0, and 27.9 ± 41.1 g s-1 using ISCST3 and 0.9 ± 0.9, 10.5 ± 18.8, and 43.0 ± 79.9 g s-1 using AERMOD, respectively. ISCST3 emission rates for the combined tillage operations for PM2.5, PM10, and TSP were 0.15 ± 0.24, 0.44 ± 0.17, and 1.4 kg acre-1, while AERMOD rates were 0.17 ± 0.27, 0.66 ± 0.25, and 2.1 kg acre-1, respectively. ISCST3 emissions for the conventional tillage operations for PM2.5, PM10, and TSP were 0.47 ± 2.1, 1.1 ± 0.23, and 3.4 kg acre-1, and the AERMOD rates were 0.18 ± 0.26, 1.2 ± 0.24, and 5.1 kg acre-1, respectively.
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Huang, Qizhi. "Topics in 21-cm cosmology : foreground models and their subtraction, map reconstruction for wide field of view interferometers and PAON-4 data analysis." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS373/document.
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Certains aspects de l'extraction du signal cosmologique à 21 cm à partir des observations radio, ainsi que le traitement des données interférométriques pour des observations depuis le sol et depuis l'espace ont été étudiés et sont présentés dans cette thèse. J'ai développé un modèle cohérent et à haute résolution du ciel en radio, qui peut fournir une carte complète et précise du ciel, dans la gamme de fréquence 10 MHz à 2,3 GHz, avec une résolution pouvant atteindre une minute d'arc. Le modèle inclut plusieurs sources de rayonnement diffus, en particulier le synchrotron Galactique, les sources radio brillantes du ciel, ainsi qu'un modèle des sources faibles. J'ai également mis au point une méthode pour extraire le signal 21 cm cosmologique, fortement contaminé par les émissions d'avant-plan et le bruit des récepteurs. La méthode utilise une cascade de deux filtres de Wiener, dans l'espace des fréquences d'abord, et ensuite, dans le domaine angulaire. Le premier filtre exploite les variations lentes des émissions d'avant-plan selon la fréquence, tandis que le second filtre exploite les corrélations angulaires du signal cosmologique pour filtrer le bruit des récepteurs, considéré non corrélé entre deux directions différentes. J'ai développé un nouvel algorithme d'imagerie pour les interféromètres en orbite lunaire. Un tel instrument serait idéal pour cartographier le ciel en dessous de 30 MHz; il ne serait en effet pas soumis aux perturbations ionosphériques et serait protégé des interférences électromagnétiques dues aux émissions terrestres. J'ai montré que l'utilisation de la précession du plan orbital du satellite permet de résoudre le problème de la symétrie miroir. La méthode exploite la relation de projection linéaire entre la carte du ciel et les visibilités mesurées, tant dans l'espace angulaire que dans l'espace des harmoniques sphériques pour reconstruire la carte du ciel. L'algorithme d'imagerie gère la complication due à l'ombre de la Lune se déplaçant avec le temps sur le champ de vue des antennes couvrant tout le ciel. Notons que ces effets ne sont pas pris en charge par les algorithmes d'imagerie existants tels que la W-Projection et la WStacking. Enfin, j'ai effectué une première analyse des données de l'interféromètre de transit PAON-4. J'ai évalué la performance globale du réseau en termes de température de bruit et de la réponse des antennes. J'ai pu étalonner avec succès les visibilités, en déterminant à la fois l'amplitude et la phase des termes de gain complexes, tout en corrigeant les décalages de pointage des antennes de PAON4. J'ai ensuite reconstruit la carte du ciel pour une bande de 10 degrés autour de la déclinaison de la source brillante Cygnus A, à partir du flot de données PAON-4 calibré et nettoyé, en appliquant l'algorithme de décomposition en mode m dans l'espace des harmoniques sphériquesSome aspects of extracting cosmological 21cm signal from radio observations, as well as processing of interferometric data for ground based or space born instruments have been studied and discussed in this dissertation. I have developed a high-resolution self-consistent radio whole sky model, which provides an accurate full sky maps in the frequency range from 10 MHz to 2.3 GHz, with angular resolution up to 1 arcmin. It includes bright and faint radio sources, Galactic synchrotron and Galactic freefree emissions. I have also developed a method to extract the faint cosmological 21-cm signal, heavily contaminated by foreground emissions and receiver noise. The method uses a cascade of two Wiener filters, in frequency domain and then, in angular domain. The first filter exploits the smoothness of the foreground emissions along the frequency, while the second filter exploits the angular correlations of the cosmological signal, due to the receiver noise is considered to be nearly uncorrelated between different directions. I have developed a studied the performance of a new imaging algorithm for lunar orbit interferometers. Such an instrument would be ideal for mapping the radio sky below 30 MHz, as it would be free from ionospheric perturbations, as well as electromagnetic interferences due to terrestrial emissions. I have shown that we make use of the precession of satellite orbital plane to solve the mirror symmetry problem, and exploit the linear mapping between the sky map and the measured visibilities, both in angular space and spherical harmonic space to reconstruct the sky map. The imaging algorithm handles the time-varying Moon's blockage over the whole sky field of view, which are not handled by existing imaging algorithms such as the WProjection and the W-Stacking. Finally, I have carried out a first analysis of the observational visibility data from the PAON-4 transit interferometer. I have evaluated the overall performance of the array in terms of system temperature and antenna response, and successfully calibrated the visibilities, determining both amplitude and phase of the complex gain terms, while correcting PAON-4 antennae pointing offsets. I have then reconstructed the sky map for a 10 degree strip around Cygnus A declination, from the cleaned calibrated PAON-4 data streams, applying the m-mode decomposition map-making algorithm in spherical harmonic space
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Zohora, Fatematuz. "Study of pipe leak fluid dynamic characteristics and their influences on acoustic emission generation." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/207823/1/Fatematuz_Zohora_Thesis.pdf.
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Developing a robust pipe leak monitoring tool is essential as it continuously monitors pipeline health without disrupting normal operation. It is critical to understand the physical phenomena in the leakage area to develop a robust pipeline condition monitoring. This research project provides a better understanding of pipe leakage fluid dynamics and their influences on acoustic emission signal generation. The findings obtained from this project lay the groundwork for the development of a robust pipeline condition monitoring technique that could be implemented without disrupting normal operation. Such a monitoring tool would have significant financial, environmental, and social benefits.
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Sangameswaran, Sivaramakrishnan. "Evaluation of Productivity, Consumption, and Uncontrolled Total Particulate Matter Emission Factors of Recyclable Abrasives." ScholarWorks@UNO, 2006. http://scholarworks.uno.edu/td/390.
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Dry abrasive blasting is a commonly used surface preparation operation by many process industries to clean up metallic surfaces and achieve surface finishes suitable for future adhesion. Abrasives used in this process can be recyclable or expendable. This study was undertaken to evaluate the performance of three recyclable abrasives: garnet, barshot and steel grit/shot in terms of productivity (area cleaned per unit time), consumption (amount of abrasive used per unit area cleaned) and uncontrolled total particulate matter (TPM) emission factors (in terms of mass of pollutant emitted per unit area cleaned and mass of pollutant emitted per unit mass of abrasive consumed). Though there have been various attempts in the past to evaluate the performance of these abrasives, there has not been a streamlined approach to evaluate these parameters in the commonly used range of process conditions, or to identify and model the influences of key process variables on these performance parameters. The first step in this study was to evaluate the performance of these three abrasives in blasting painted steel panels under enclosed blasting conditions and using USEPA recommended protocols. The second step was to model the influences of blast pressure and abrasive feed rate, two most critical parameters on productivity, consumption and emission factors. Two and three dimensional models were obtained using multiple linear regression techniques to express productivity, consumption and TPM emission factors in terms of blast pressure and abrasive feed rate. Barshot was found to have high productivities over all and steel grit/shot demonstrated the least emission potential at almost all of the tested pressure and feed rate conditions. The data will help fill the gaps in literature currently available for dry abrasive blasting performance. The models obtained will help industries, the research community and the regulatory agencies to make accurate estimates of the performance parameters. Estimating productivity and consumption will help industries identify best management practices by optimizing the process conditions to achieve high productivity and low consumption rates. Emission factor determination will help in reducing the emissions to the atmosphere by choosing process conditions corresponding to minimum emissions. The performance parameters once optimized can result in reduction in material, labor, energy, emission and disposal costs, lower resource utilization and hence reduction in overall life cycle costs of dry abrasive process. The developed models will help industries in making environmentally preferable purchases thereby promoting source reduction options. PM emissions estimated using the models presented here will aid studies on health risk associated with inhalation of atmospheric PM.
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Topping, Geoffrey John. "Positron emission tomography region of interest and parametric image analysis methods for severely-lesioned small animal disease models." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2654.
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Small animal positron emission tomography (PET) image analysis can be particularly challenging with heavily-lesioned animal disease models with limited tracer uptake such as the 6-hydroxydopamine (OHDA) lesioned rat model of Parkinson's disease. Methodology-related variations in measured values of 10% or 15% can obscure meaningful biological differences, so accurate analysis methods are essential. However, placing regions of interest (ROIs) on these images without additional guidance is unreliable, and can lead to significant errors in results. To address this problem, this work develops a partly atlas-guided method place ROIs on structures that lack specific binding with presynaptic dopaminergic tracers. The method is tested by correlation of PET binding potential (BP) with autoradiographic binding measurements, and with repeated PET scans of the same subjects, both with the presynaptic tracer ¹¹C-dihydrotetrabenazine (DTBZ). The method is found to produce reliable results.
When directly comparing PET images of the same subject to detect changes, it is essential to minimize variations due to analysis method. To this end, a masking method for automated image registration (AIR) of PET images with dopaminergic tracer rat images is developed. Coregistration with AIR and separate ROI placement are compared and tested with repeated scans of the same rat with DTBZ, and are found to be equivalent.
Kinetic modelling algorithms may also introduce bias or scatter to binding potentials (BP) calculated from TACs or in parametric images. To determine the optimal method for this step, algorithms for dopaminergic tracers are compared for small animal DTBZ, ¹¹C-methylphenidate (MP), and ¹¹C-raclopride (Rac) data. Among the tested methods is a new variant of the Logan graphical kinetic modelling method, developed in this work, that issignificantly less biased by target tissue TAC noise than the standard Logan approach. The modified graphical method is further compared with the Logan graphical algorithms with added-noise simulations. The simplified reference tissue model (SRTM) is found to have the best method for ROI TAC data, while the modified graphical algorithm may be preferred when generating parametric images.
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Foudray, Angela Marie Klohs. "Design of an advanced positron emission tomography detector system and algorithms for imaging small animal models of human disease." Diss., [La Jolla, Calif.] : University of California, San Diego, 2009. http://wwwlib.umi.com/cr/ucsd/fullcit?p3344655.
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Thesis (Ph. D.)--University of California, San Diego, 2009.Title from first page of PDF file (viewed March 19, 2009). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 404-423).
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Gregory, Scott G. "T Tauri stars : mass accretion and X-ray emission." Thesis, St Andrews, 2007. http://hdl.handle.net/10023/336.
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Martin, M. J. "Models of the interactive effects of rising ozone, carbon dioxide and temperature on canopy carbon dioxide exchange and isoprene emission." Thesis, University of Essex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339238.
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Krishnamurthy, Senthil. "Development of decomposition methods for solution of a multiarea power dispatch optimisation problem." Thesis, Cape Peninsula University of Technology, 2013. http://hdl.handle.net/20.500.11838/1193.
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Thesis submitted in fulfilment of the requirements for the degree
Doctor of Technology: Electrical Engineering
in the Faculty of Engineering
at the Cape Peninsula University of Technology
2013The objective of the economic dispatch problem of electrical power generation is to schedule the committed generating unit outputs to meet the required load demand while satisfying the system equality and inequality constraints. The thesis formulates single area and multi-area Combined Economic Emission Dispatch (CEED) problem as single criterion, bi-criterion and multi-criteria optimisation problems based on fuel cost and emission criterion functions, constraints over the operational limits of the generator and the tie-lines, and requirements for a balance between the produced power and the system demand and power loss. Various methods, algorithms and softwares are developed to find solution of the formulated problems in single area and multi-area power systems. The developed methods are based on the classical Lagrange's and on the meta-heuristic Particle Swarm Optimisation (PSO) techniques for a single criterion function. Transformation of the bi-criteria or multi-criteria dispatch problem to a single criterion one is done by some existing and two proposed in the thesis penalty factors. The solution of the CEED problems is obtained through implementation of the developed software in a sequential way using a single computer, or in a data-parallel way in a Matlab Cluster of Computers (CC). The capabilities of the developed Lagrange's and PSO algorithms are compared on the basis of the obtained results. The conclusion is that the Lagrange's method and algorithm allows to receive better solution for less computation time. Data-parallel implementation of the developed software allows a lot of results to be obtained for the same problem using different values of some of the problem parameters. According to the literature papers, there are many algorithms available to solve the CEED problem for the single area power systems using sequential methods of optimisation, but they consume more computation time to solve this problem. The thesis aim is to develop a decomposition-coordinating algorithm for solution of the Multi Area Economic Emission Dispatch (MAEED) problem of power systems. The MAEED problem deals with the optimal power dispatch inside and between the multiple areas and addresses the environmental issue during the economic dispatch. To ensure the system security, tie-line transfer limits between different areas are incorporated as a set of constraints in the optimisation problem. A decomposition coordinating method based on the Lagrange's algorithm is developed to derive a set of optimal solutions to minimize the fuel cost and emissions of the multi-area power systems. An augmented function of Lagrange is applied and its decomposition in interconnected sub problems is done using a new coordinating-vector. Task-parallel computing in a Matlab Cluster is used to solve the multi-area dispatch problem. The calculations and tasks allocation to the Cluster workers are based on a shared memory architecture. Implementation of the calculation algorithm using a Cluster of Computers allows quick and simpler solutions to the multi-area CEED problem. The thesis applied the developed algorithms for the various problem formulation scenarios, i.e. fuel cost and emission function with and without valve point loading effect, quadratic and cubic fuel cost and emission functions. The various IEEE benchmark models are used to test the developed Lagrange's and PSO algorithms in the sequential, data-parallel, and task-parallel implementations. Developed methods, algorithms and software programmes can be applied for solution of various energy management problems in the regional and national control centres, smart grid applications, and in education and research institutions.
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Xu, Li. "Financial and computational models in electricity markets." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51849.
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This dissertation is dedicated to study the design and utilization of financial contracts and pricing mechanisms for managing the demand/price risks in electricity markets and the price risks in carbon emission markets from different perspectives. We address the issues pertaining to the efficient computational algorithms for pricing complex financial options which include many structured energy financial contracts and the design of economic mechanisms for managing the risks associated with increasing penetration of renewable energy resources and with trading emission allowance permits in the restructured electric power industry. To address the computational challenges arising from pricing exotic energy derivatives designed for various hedging purposes in electricity markets, we develop a generic computational framework based on a fast transform method, which attains asymptotically optimal computational complexity and exponential convergence. For the purpose of absorbing the variability and uncertainties of renewable energy resources in a smart grid, we propose an incentive-based contract design for thermostatically controlled loads (TCLs) to encourage end users' participation as a source of DR. Finally, we propose a market-based approach to mitigate the emission permit price risks faced by generation companies in a cap-and-trade system. Through a stylized economic model, we illustrate that the trading of properly designed financial options on emission permits reduces permit price volatility and the total emission reduction cost.
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Cieslar, Filip. "Modely a simulace pochodů bezemisního kolového nakladače s elektrickým pohonem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-442865.
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This diploma thesis deals with the creation of models simulating the processes of an emission-free wheel loader, which was created by rebuilding the original version with a combustion engine. Part of the work is the methodical creation of models from the basic part of the machine to a simplified model of the overall machine, its functional verification and calibration based on available information’s and measurements. In this paper, selected parameters of the overall machine model are verified based on performed measurements, the suitability of selected components is verified, and the optimization and modification of the model is performed based on verification. The aim of the thesis is to present the simulation and verification procedure and its practical use in the development of an emission-free wheel loader with electric drive.