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Impacts of Biofuel Production and Navigation Impediments on Agricultural Transportation and MarketsAhmedov, Zafarbek 16 December 2013 (has links)
This study investigated the impacts of U.S. biofuel production and barge navigation impediments on agricultural transportation and markets. Both past and future impacts of U.S. biofuel production levels mandated by the Renewable Fuel Standards of the Energy Policy Act of 2005 (RFS1) and the Energy Independence and Security Act of 2007 (RFS2) were examined. Examination of barge navigations impediments included analysis of the impact of lock failure and low water levels on rivers due to drought, on agricultural transportation, and on consumer welfare. All scenarios were simulated using the International Grain Transportation Model, a price endogenous mathematical programming model.
The results showed that RFS-associated (RFS1 and RFS2) U.S. corn ethanol production increased the total corn supply and diverted corn from non-ethanol consumption, reduced regional grain transportation volumes, and contributed to a rise in corn prices. The results of the forward-looking scenarios indicated that grain exports and transport volumes were increased. Exports from Gulf ports increased by 41%, while grain movements by rail increased by 60%. Additional investments in the expansion of the grain handling capacities of Gulf ports and the railroad industry are needed in the near future unless a large increase in biofuel production occurs.
The results of navigation impediment scenarios indicated that both lock failures and low water levels on rivers adversely affect U.S. grain exports. The Gulf ports were most negatively impacted, relative to Pacific Northwest and Atlantic ports. Truck and barge freight volume declined while rail freight volume increased. Because trucks deliver grain from grain elevators to barge locations, truck volume also decreased in response to the decline in barge volume. The scenarios imposed welfare losses on society with most accruing to consumers, while the barge industry lost $10-154 million in revenue. The low water levels were more expensive than the lock failures. Major rehabilitation of the locks is needed to avoid lock failures and more dredging of the shallow parts of the river system is required because of frequent droughts.
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Lantano oksidinių junginių gamyba zolis – gelis metodu ir jų Rentgeno fotoelektronų spektrų tyrimas / Synthesis of Lanthanum oxide compounds by using sol - gel method and their X-ray study of photoelectron spectraMomkus, Audrius 06 August 2012 (has links)
Darbo tikslas yra pagaminti La2O3 sluoksnius, atkaitinant prie aukštų temperatūrų nenaudojant vakuumo ir ištirti gautų sluoksnių Rentgeno fotoelektronų spektrus. Darbe aprašyti Rentgeno fotoelektronų spektroskopijos (RFS) (XPS - X-ray photoelectron spectroscopy) metodo, naudojamo įvairių medžiagų paviršių cheminei sudėčiai nustatyti, pagrindai. Pirmajame skyriuje aprašytas Rentgeno fotoelektroninės spektroskopijos metodas, pagrindinė RFS aparatūra bei teorinė dalis. Antrajame skyriuje aprašyti: La2O3 oksidiniai junginiai ir jų tyrimų metodika, plonų nanostruktūrizuotų medžiagų sluoksnių nusodinimo iš dujų fazės (plazmos) metodas- magnetroninis dulkinimas (magnetron sputtering), aparatūra ir zolis – gelis metodas. Trečiasis skyrius yra skirtas Rentgeno fotoelektroninių spektrų matavimų, naudojant spektrometrą XSAM 800 (Kratos Analytical, Didžioji Britanija) ypatumams ir bandinių gamybos metodikai aptarti. Pateiktas išsamus La2O3 sintezės zolių-gelių metodu technologijos aprašymas. Ketvirtajame skyriuje pateikiami eksperimentiniai rezultatai gauti, matuojant La2O3 Rentgeno fotoelektronų spektrus. Darbo pabaigoje yra pateikiamos išvados, kurios galėtų būti naudingos, tobulinant La2O3 bandinių gamybos technologiją. Gautas rezultatas: nustatyta, kad zolių – gelių technologija leidžia paprastais metodais, nenaudojant sudėtingos aparatūros,bei vakuuminės įrangos susintetinti La2O3. / The aim of presented work was to synthesis by using sol-gel technology and investigate the X- ray photoelectron spectra (XPS) of La2O3 thin films in the annealed high temperature and without using vacuum installation. In the present work we described the essentials of the method of X-ray photoelectron spectroscopy, used to determine chemical composition of various materials. In the first part describes the X- ray photo-electronic spectroscopy method, basic XPS equipment and theoretical part. The second part are described: La2O3 oxide compounds and the methods of their production from the gas phase – magnetron sputtering and sol – gel method. In the third part we discussed the peculiarities and methodology of spectrometer XSAM 800 (Kratos Analytical, Great Britain) samples production while measuring X-ray photoelectron spectra. The thorough description of the technology by synthesis of La2O3 sol-gel method was provided. The fourth part presents the experimental results obtained by measuring the La2O3X-ray photoelectron spectra. In the end of the work conclusions are produced that could be useful in improving production technology of La2O3 samples. Obtained results: we identified that sol-gel technology allows synthesizing La2O3 by simple methods, without using sophisticated equipment and vacuum installation.
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Lantano oksidų sintezė ir rentgeno fotoelektrinių spektrų tyrimas / Synthesis and XPS study of La2O3 filmsMasevičius, Artūras 15 July 2011 (has links)
Darbo tikslas yra ištirti atkaitintų prie aukštų temperatūrų vakuume La2O3 sluoksnių Rentgeno fotoelektronų spektrus. Darbe aprašyti Rentgeno fotoelektronų spektroskopijos (RFS) (XPS - X-ray photoelectron spectroscopy) metodo, naudojamo įvairių medžiagų paviršių cheminei sudėčiai nustatyti, pagrindai. Pirmame skyriuje aprašyti: La2O3 oksidiniai junginiai ir jų tyrimų metodika, plonų nanostruktūrizuotų medžiagų sluoksnių nusodinimo iš dujų fazės (plazmos) metodas- magnetroninis dulkinimas (magnetron sputtering), aparatūra ir zolis – gelis metodas. Antrajame skyriuje aprašytas Rentgeno fotoelektroninės spektroskopijos metodas, pagrindinė RFS aparatūra bei teorinė dalis. Trečiasis skyrius yra skirtas Rentgeno fotoelektroninių spektrų matavimų, naudojant spektrometrą XSAM 800 (Kratos Analytical, Didžioji Britanija) ypatumams ir bandinių gamybos metodikai aptarti. Pateiktas išsamus La2O3 sintezės zolių-gelių metodu technologijos aprašymas. Ketvirtajame skyriuje pateikiami eksperimentiniai rezultatai gauti, matuojant La2O3 Rentgeno fotoelektronų spektrus. Darbo pabaigoje yra pateikiamos išvados, kurios galėtų būti naudingos, tobulinant La2O3 bandinių gamybos technologiją. Gautas rezultatas: nustatyta, kad zolių – gelių technologija leidžia paprastais metodais, nenaudojant sudėtingos aparatūros, susintetinti La2O3. / The aim of presented work was to synthesis by using sol-gel technology and investigate the X-ray photoelectron spectra (XPS) of La2O3 thin films in the annealed high temperature vacuum. In the present work we described the essentials of the method of X-ray photoelectron spectroscopy, used to determine chemical composition of various materials. In the first part are described: La2O3 oxide compounds and the methods of the their production from the gas phase – magnetron sputtering and sol – gel method. The second part describes the X- ray photo-electronic spectroscopy method, basic XPS equipment and theoretical part. In the third part we discussed the peculiarities and methodology of spectrometer XSAM 800 (Kratos Analytical, Great Britain) samples production while measuring X-ray photoelectron spectra. The thorough description of the technology by synthesis of La2O3 sol-gel method was provided. The fourth part presents the experimental results obtained by measuring the La2O3 X-ray photoelectron spectra. In the end of the work conclusions are produced that could be useful in improving production technology of La2O3 samples. Obtained results: we identified that sol-gel technology allows to synthesize La2O3 by simple methods, without using sophisticated equipment.
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Barriers Impacting United States Advanced Biofuel ProjectsWithers, Jeremy W. 14 July 2016 (has links)
Although the 2005 EPAct was enacted to help bolster the emerging biofuel industry, 52% of advanced biofuel projects were closed or shut down by 2015. However, there are no complete lists of barriers that impeded these projects. The goal of this study was to develop a framework of barriers impeding success of advanced biofuel projects by conducting a literature review of barriers, spatial analysis of status, survey of barriers, and determination of coproducts and byproducts and their marketing and distribution barriers from the industry stakeholders.
The spatial analysis indicated 59 biofuel projects were attempted, and their Eastern and Western location by status was not a barrier. Using Grounded Theory, nine barriers were derived and aggregated in major categories, including product development, strategy, technology, competition, energy costs, funding, government, suppliers, and third-party relations. A contingency analysis was conducted relating their status to internal and external barriers, indicating no relationship between type of closing and type of barrier. Next, the number of barriers was expanded to 23, and a survey was conducted to gain knowledge on these barriers from industry stakeholders. When comparing the barriers by stakeholders, there were differences based on status, type, and technology of the projects. In addition, the survey and discussion identified 79 barriers different across years, type of industry (pilot, demonstration, or commercial), status (open, closed, or planning), and technology (thermochemical, biochemical, or hybrid). Forty-seven coproducts and byproducts and many unknown barriers to their marketability and distribution were determined and ranked by primary and secondary barriers. These extensive lists of barriers and coproducts will aid future biofuels projects in their planning, research, and development stages. / Master of Science
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Análise e comparação de alguns métodos alternativos de seleção de variáveis preditoras no modelo de regressão linear / Analysis and comparison of some alternative methods of selection of predictor variables in linear regression models.Marques, Matheus Augustus Pumputis 04 June 2018 (has links)
Neste trabalho estudam-se alguns novos métodos de seleção de variáveis no contexto da regressão linear que surgiram nos últimos 15 anos, especificamente o LARS - Least Angle Regression, o NAMS - Noise Addition Model Selection, a Razão de Falsa Seleção - RFS (FSR em inglês), o LASSO Bayesiano e o Spike-and-Slab LASSO. A metodologia foi a análise e comparação dos métodos estudados e aplicações. Após esse estudo, realizam-se aplicações em bases de dados reais e um estudo de simulação, em que todos os métodos se mostraram promissores, com os métodos Bayesianos apresentando os melhores resultados. / In this work, some new variable selection methods that have appeared in the last 15 years in the context of linear regression are studied, specifically the LARS - Least Angle Regression, the NAMS - Noise Addition Model Selection, the False Selection Rate - FSR, the Bayesian LASSO and the Spike-and-Slab LASSO. The methodology was the analysis and comparison of the studied methods. After this study, applications to real data bases are made, as well as a simulation study, in which all methods are shown to be promising, with the Bayesian methods showing the best results.
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Análise e comparação de alguns métodos alternativos de seleção de variáveis preditoras no modelo de regressão linear / Analysis and comparison of some alternative methods of selection of predictor variables in linear regression models.Matheus Augustus Pumputis Marques 04 June 2018 (has links)
Neste trabalho estudam-se alguns novos métodos de seleção de variáveis no contexto da regressão linear que surgiram nos últimos 15 anos, especificamente o LARS - Least Angle Regression, o NAMS - Noise Addition Model Selection, a Razão de Falsa Seleção - RFS (FSR em inglês), o LASSO Bayesiano e o Spike-and-Slab LASSO. A metodologia foi a análise e comparação dos métodos estudados e aplicações. Após esse estudo, realizam-se aplicações em bases de dados reais e um estudo de simulação, em que todos os métodos se mostraram promissores, com os métodos Bayesianos apresentando os melhores resultados. / In this work, some new variable selection methods that have appeared in the last 15 years in the context of linear regression are studied, specifically the LARS - Least Angle Regression, the NAMS - Noise Addition Model Selection, the False Selection Rate - FSR, the Bayesian LASSO and the Spike-and-Slab LASSO. The methodology was the analysis and comparison of the studied methods. After this study, applications to real data bases are made, as well as a simulation study, in which all methods are shown to be promising, with the Bayesian methods showing the best results.
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Numerical Simulations of the Gravitational Geodynamo and its Time Spectrum / Numerische Simulationen des gravitationsgetriebenen Dynamos und sein zeitliches SpektrumTanriverdi, Vedat 28 June 2011 (has links)
No description available.
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Odhad dechové frekvence z elektrokardiogramu a fotopletysmogramu / Breathing Rate Estimation from the Electrocardiogram and PhotoplethysmogramJanáková, Jaroslava January 2021 (has links)
The master thesis deals with the issue of gaining the respiratory rate from ECG and PPG signals, which are not only in clinical practice widely used measurable signals. The theoretical part of the work outlines the issue of obtaining a breath curve from these signals. The practical part of the work is focused on the implementation of five selected methods and their final evaluation and comparison.
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Advanced signal processing techniques for multi-target trackingDaniyan, Abdullahi January 2018 (has links)
The multi-target tracking problem essentially involves the recursive joint estimation of the state of unknown and time-varying number of targets present in a tracking scene, given a series of observations. This problem becomes more challenging because the sequence of observations is noisy and can become corrupted due to miss-detections and false alarms/clutter. Additionally, the detected observations are indistinguishable from clutter. Furthermore, whether the target(s) of interest are point or extended (in terms of spatial extent) poses even more technical challenges. An approach known as random finite sets provides an elegant and rigorous framework for the handling of the multi-target tracking problem. With a random finite sets formulation, both the multi-target states and multi-target observations are modelled as finite set valued random variables, that is, random variables which are random in both the number of elements and the values of the elements themselves. Furthermore, compared to other approaches, the random finite sets approach possesses a desirable characteristic of being free of explicit data association prior to tracking. In addition, a framework is available for dealing with random finite sets and is known as finite sets statistics. In this thesis, advanced signal processing techniques are employed to provide enhancements to and develop new random finite sets based multi-target tracking algorithms for the tracking of both point and extended targets with the aim to improve tracking performance in cluttered environments. To this end, firstly, a new and efficient Kalman-gain aided sequential Monte Carlo probability hypothesis density (KG-SMC-PHD) filter and a cardinalised particle probability hypothesis density (KG-SMC-CPHD) filter are proposed. These filters employ the Kalman- gain approach during weight update to correct predicted particle states by minimising the mean square error between the estimated measurement and the actual measurement received at a given time in order to arrive at a more accurate posterior. This technique identifies and selects those particles belonging to a particular target from a given PHD for state correction during weight computation. The proposed SMC-CPHD filter provides a better estimate of the number of targets. Besides the improved tracking accuracy, fewer particles are required in the proposed approach. Simulation results confirm the improved tracking performance when evaluated with different measures. Secondly, the KG-SMC-(C)PHD filters are particle filter (PF) based and as with PFs, they require a process known as resampling to avoid the problem of degeneracy. This thesis proposes a new resampling scheme to address a problem with the systematic resampling method which causes a high tendency of resampling very low weight particles especially when a large number of resampled particles are required; which in turn affect state estimation. Thirdly, the KG-SMC-(C)PHD filters proposed in this thesis perform filtering and not tracking , that is, they provide only point estimates of target states but do not provide connected estimates of target trajectories from one time step to the next. A new post processing step using game theory as a solution to this filtering - tracking problem is proposed. This approach was named the GTDA method. This method was employed in the KG-SMC-(C)PHD filter as a post processing technique and was evaluated using both simulated and real data obtained using the NI-USRP software defined radio platform in a passive bi-static radar system. Lastly, a new technique for the joint tracking and labelling of multiple extended targets is proposed. To achieve multiple extended target tracking using this technique, models for the target measurement rate, kinematic component and target extension are defined and jointly propagated in time under the generalised labelled multi-Bernoulli (GLMB) filter framework. The GLMB filter is a random finite sets-based filter. In particular, a Poisson mixture variational Bayesian (PMVB) model is developed to simultaneously estimate the measurement rate of multiple extended targets and extended target extension was modelled using B-splines. The proposed method was evaluated with various performance metrics in order to demonstrate its effectiveness in tracking multiple extended targets.
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