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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

Agricultura e estrutura produtiva do estado do Mato Grosso: uma análise insumo-produto. / Agriculture and productive framework of Mato Grosso state: an input-outup analysis.

Figueiredo, Margarida Garcia de 21 January 2004 (has links)
O presente trabalho tem como principal objetivo mostrar de forma empírica a importância relativa do setor agrícola na estrutura produtiva do estado do Mato Grosso, o qual tem apresentado um excepcional desempenho da atividade agrícola no contexto atual. Para tanto, utiliza-se de um modelo insumo-produto inter-regional construído para duas regiões, a saber, Mato Grosso e resto do Brasil, referente ao ano de 1999. A partir dos indicadores desta metodologia, procura-se identificar os setores mais importantes das economias em questão, seus encadeamentos e a propagação de impactos entre as regiões. Além disso, o trabalho faz ainda uma aplicação do modelo para verificar qual o impacto das exportações mato-grossenses, em especial da soja, sobre a produção total, valor adicionado e número de empregos gerados na economia, bem como calcula o PIB do agronegócio da soja no Mato Grosso, além de verificar qual o impacto causado na produção dos transportes rodoviário e ferroviário, nas duas regiões, ao atender a demanda final de cada atividade pertencente ao estado do Mato Grosso. Pelos resultados obtidos, pode-se confirmar a hipótese formulada a respeito da importância dos setores primários para a economia do estado. De acordo com os índices puros de ligações, verificou-se que os setores agrícolas como Soja, Bovinos e Outros da pecuária, foram considerados como chave ou pólos de desenvolvimento econômico na região em estudo, em função de suas fortes relações de compra e venda de insumos na economia. Além destes, quatro setores diretamente relacionados à agropecuária foram também identificados como chave, a saber: Fabricação de óleos vegetais, Abate de bovinos, Abate de outros animais e Álcool. Em especial merece destaque a cultura da soja no Mato Grosso, que embora tenha uma baixa geração direta de emprego e renda, apresenta um elevado efeito multiplicador destas variáveis na economia, uma característica intrínseca de setores altamente produtivos e intensivos em capital, além de destacar-se também como pólo de desenvolvimento econômico em função de suas fortes ligações, conforme mencionado no parágrafo anterior. As evidências empíricas confirmaram também a importância do setor em termos de suas exportações, as quais causam importante impacto na produção e geração de empregos em diversos outros setores, além de atrair ganhos cambiais ao país. Finalmente, o trabalho desenvolve um ferramental útil para a formulação de políticas públicas para o estado do Mato Grosso, embora sejam necessárias algumas atualizações e refinamentos da metodologia utilizada, para que se possa desenvolver um instrumental de avaliação de políticas de estímulo ao desenvolvimento da infra-estrutura de transportes da região, uma vez que esta última constitui-se peça fundamental ao crescimento econômico. / The main goal of this study is to show the empiric frame of the relative importance of agricultural sector into the productive framework of the Mato Grosso State, which has shown an exceptional agricultural activities growth in the actual context. For this purposes, it becomes useful to adopt an inter-regional input-output model built for two regions: Mato Grosso State and rest of Brazil, regarding to 1999. From the indicators of this methodology, it looks for finding the more important sectors of those economies, and its linkages and impacts between the regions as well. Moreover, this study even encourages to make some simulations to verify how the Mato Grosso’s exportations impacts on the total product, income and employment, specially those ones originated from soybean. It was possible to calculate the Mato Grosso’s soybean agribusiness GDP (Gross Domestic Product), besides verifying how much impacts were generated on highways and railways transports. According to results obtained, it is possible to confirm the created hypotheses regarding importance of primary sectors for the state economy. According to pure linkages indexes, it was checked that some sectors such soybean production, beef cattle production and other ones were considered like key sectors or economic developed pools for the region studied. In addition of those ones, four other sectors directly linked with agriculture were also found out like key sectors, so they are vegetable oils production, beef cattle and other slaughters, and alcohol production. The soybean crops is really a spot in Mato Grosso State, even though it has a low generation of directs income and employment. As a matter of fact, the soybean crops have a high multiplier effect on these economy variables, an own feature of highly productive and capital intensive sectors, and it is a prominence sector like a developing economic pool, as seen before. The empiric evidences confirmed the importance of sector in terms of its exportations too, which strongly impacts on product and employments generation in other ones sectors, besides attracting exchanges gains to the country. Finally, this input-output analysis creates an important tool to the public policy formulations of Mato Grosso State, although its important to make some updates and fits on the methodology applied to be able developing a whole evaluation instrumental kit of entire stimulant policies that might develop for example an efficient regional transport structure, due to this one consists of an essential device to the economic growth.
432

Quantifying the global cropland footprint of the European Union's non-food bioeconomy

Bruckner, Martin, Häyhä, Tiina, Giljum, Stefan, Maus, Victor, Fischer, Günther, Tramberend, Sylvia, Boerner, Jan 18 February 2019 (has links) (PDF)
A rapidly growing share of global agricultural areas is devoted to the production of biomass for non-food purposes. The expanding non-food bioeconomy can have far-reaching social and ecological implications; yet, the non-food sector has attained little attention in land footprint studies. This paper provides the first assessment of the global cropland footprint of non-food products of the European Union (EU), a globally important region regarding its expanding bio-based economy. We apply a novel hybrid land flow accounting model, combining the biophysical trade model LANDFLOW with the multi-regional input-output model EXIOBASE. The developed hybrid approach improves the level of product and country detail, while comprehensively covering all global supply chains from agricultural production to final consumption, including highly-processed products, such as many non-food products. The results highlight the EU's role as a major processing and the biggest consuming region of cropland-based non-food products while at the same time relying heavily on imports. Two thirds of the cropland required to satisfy the EU's non-food biomass consumption are located in other world regions, particularly in China, the US and Indonesia, giving rise to potential impacts on distant ecosystems. With almost 39% in 2010, oilseeds used to produce for example biofuels, detergents and polymers represented the dominant share of the EU's non-food cropland demand. Traditional non-food biomass uses, such as fibre crops for textiles and animal hides and skins for leather products, also contributed notably (22%). Our findings suggest that if the EU Bioeconomy Strategy is to support global sustainable development, a detailed monitoring of land use displacement and spillover effects is decisive for targeted and effective EU policy making.
433

Any Effect of Gymnastics Training on Upper-Body and Lower-Body Aerobic and Power Components in National and International Male Gymnast?

Jemni, Monem, Sands, William A., Friemel, Françoise, Stone, Michael H., Cooke, Carlton B. 01 November 2006 (has links)
Aerobic and anaerobic performance of the upper body (UB) and lower body (LB) were assessed by arm cranking and treadmill tests respectively in a comparison of national (N) and international (I) male gymnasts. Force velocity and Wingate tests were performed using cycle ergometers for both arms and legs. In spite of a significant difference in training volume (4–12 vs. 27–34 h·wk−1 for N and I, respectively), there was no significant difference between N and I in aerobic and anaerobic performance. Upper body and LB maximal oxygen uptake (JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max) values were 34.44 ± 4.62 and 48.64 ± 4.63 ml·kg−1·min−1 vs. 33.39 ± 4.77 and 49.49 ± 5.47 ml·kg−1·min−1, respectively, for N and I. Both N and I had a high lactic threshold (LT), at 76 and 82% of JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max, respectively. Values for UB and LB force velocity (9.75 ± 1.12 and 15.07 ± 4.25 vs. 10.63 ± 0.95 and 15.87 ± 1.25 W·kg−1) and Wingate power output (10.43 ± 0.74 and 10.98 ± 3.06 vs. 9.58 ± 0.60 and 13.46 ± 1.34 W·kg−1) were also consistent for N and I. These findings confirm the consistency of JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max values presented for gymnasts in the last 4 decades, together with an increase in peak power values. Consistent values for aerobic and anaerobic performance suggest that the significant difference in training volume is related to other aspects of perfomance that distinguish N from I gymnasts. Modern gymnastics training at N and I levels is characterized by a focus on relative strength and peak power. In the present study, the high LT is a reflection of the importance of strength training, which is consistent with research for sports such as wrestling. Aerobic and anaerobic performance of the upper body (UB) and lower body (LB) were assessed by arm cranking and treadmill tests respectively in a comparison of national (N) and international (I) male gymnasts. Force velocity and Wingate tests were performed using cycle ergometers for both arms and legs. In spite of a significant difference in training volume (4–12 vs. 27–34 h·wk−1 for N and I, respectively), there was no significant difference between N and I in aerobic and anaerobic performance. Upper body and LB maximal oxygen uptake (JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max) values were 34.44 ± 4.62 and 48.64 ± 4.63 ml·kg−1·min−1 vs. 33.39 ± 4.77 and 49.49 ± 5.47 ml·kg−1·min−1, respectively, for N and I. Both N and I had a high lactic threshold (LT), at 76 and 82% of JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max, respectively. Values for UB and LB force velocity (9.75 ± 1.12 and 15.07 ± 4.25 vs. 10.63 ± 0.95 and 15.87 ± 1.25 W·kg−1) and Wingate power output (10.43 ± 0.74 and 10.98 ± 3.06 vs. 9.58 ± 0.60 and 13.46 ± 1.34 W·kg−1) were also consistent for N and I. These findings confirm the consistency of JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max values presented for gymnasts in the last 4 decades, together with an increase in peak power values. Consistent values for aerobic and anaerobic performance suggest that the significant difference in training volume is related to other aspects of perfomance that distinguish N from I gymnasts. Modern gymnastics training at N and I levels is characterized by a focus on relative strength and peak power. In the present study, the high LT is a reflection of the importance of strength training, which is consistent with research for sports such as wrestling.
434

The Parser Converter Loader: An Implementation of the Computational Chemistry Output Language (CCOL)

Abel, Donald Randall 03 May 1995 (has links)
A necessity of managing scientific data is the ability to maintain experimental legacy information without continually modifying the applications that create and use that information. By facilitating the management of scientific data we hope to give scientists the ability to effectively use additional modeling applications and experimental data. We have demonstrated that an extensible interpreter, using a series of stored directives, allows the loading of data from computational chemistry applications into a generic database. Extending the interpreter to support a new application involves supplying a list of directives for each piece of information to be loaded. This research confirms that an extensible interpreter can be used to load computational chemistry experimental data into a generic database. This procedure may be applicable to the loading and retrieving of other types of experimental data without requiring modifications of the loading and retrieving applications.
435

An Optical System to Transform the Output Beam of a Quantum Cascade Laser to be Uniform

Jacobson, Jordan M. 01 May 2016 (has links)
Quantum cascade lasers (QCLs) are a candidate for calibration sources in space-based remote sensing applications. However, the output beam from a QCL has some characteristics that are undesirable in a calibration source. The output beam from a QCL is polarized both temporally and spatially coherent, and has a non-uniform bivariate Gaussian profile. These characteristics need to be mitigated before QCLs can be used as calibration sources. This study presents the design and implementation of an optical system that manipulates the output beam from a QCL so that it is spatially and angularly uniform with reduced coherence and polarization.
436

Transducer dynamics

Dolzhenko, Egor 14 December 2007 (has links)
Transducers are finite state automata with an output. In this thesis, we attempt to classify sequences that can be constructed by iteratively applying a transducer to a given word. We begin exploring this problem by considering sequences of words that can be produced by iterative application of a transducer to a given input word, i.e., identifying sequences of words of the form w, t(w), t²(w), . . . We call such sequences transducer recognizable. Also we introduce the notion of "recognition of a sequence in context", which captures the possibility of concatenating prefix and suffix words to each word in the sequence, so a given sequence of words becomes transducer recognizable. It turns out that all finite and periodic sequences of words of equal length are transducer recognizable. We also show how to construct a deterministic transducer with the least number of states recognizing a given sequence. To each transducer t we associate a two-dimensional language L²(t) consisting of blocks of symbols in the following way. The first row, w, of each block is in the input language of t, the second row is a word that t outputs on input w. Inductively, every subsequent row is a word outputted by the transducer when its preceding row is read as an input. We show a relationship of the entropy values of these two-dimensional languages to the entropy values of the one-dimensional languages that appear as input languages for finite state transducers.
437

The effect of breathing pattern retraining on performance in competitive cyclists

Vickery, Rachel L Unknown Date (has links)
The increased work of breathing associated with intense cycling has been identified as a factor that may negatively affect cycling performance. The aerodynamic position, abnormal respiratory mechanics either at rest or during exercise, and the development of a tachypnoeic breathing pattern are factors known to increase the work of breathing. Breathing pattern retraining aims to decrease the work of breathing by delaying the onset of dynamic hyperinflation and the recruitment of accessory breathing muscles. To date no studies have investigated the performance, physiological and perceptual consequences of manipulating breathing pattern in trained cyclists. Purpose: The aim of the present study was to investigate the effect of breathing pattern retraining on 20-km time trial performance and respiratory and metabolic measures in competitive cyclists. Method: Twenty-four competitive male cyclists (age 37.7 ± 8.6 years, mean ± SD; peak 4.34 ± 0.47 L·min-1) were match paired on 20-km time trial performance and assigned at random to either an intervention group (breathing pattern retraining; N = 12) or control group (N = 12). 20-km time trial performance, pulmonary function and the physiological and perceptual response during a maximal incremental cycle step test were assessed pre- and post-intervention. The intervention group underwent four weeks of specific breathing pattern retraining using exercises designed to reduce dynamic hyperinflation and optimise respiratory mechanics. The control group attended the laboratory once a week during this period and performed a 10 minute sub-maximal ride wearing a biofeedback breathing harness. The control group was led to believe the purpose for their participation was to investigate the effect that maximal exercise had on breathing pattern, and to test the reliability of the breathing harness. There was no attempt to modify the breathing pattern of the control group. Data were analysed using an MS Excel spreadsheet designed for statistical analysis. The uncertainty in the effect was expressed as 90% confidence limits and a smallest worthwhile effect of 1.0% was assumed. Results: The intervention group showed substantial improvements in 20-km time trial performance (-1.5 ± 1.1%) and incremental power (3.2 ± 3%). Additionally, breathing frequency (-13.2 ± 8.9%; -9.5 ± 8.4%), tidal volume (10.6 ± 8.5%; 9.4 ± 7.6%), inspiratory time (10.1 ± 8%; 9.4 ± 7.7%), breathing RPE (-30 ± 33.9%; -24.7 ± 28.1%) and leg RPE (-27.9 ± 38.5%; -24.7 ± 28.2%) were all positively affected at lactate threshold and lactate turn point. No positive changes were observed in the control group for 20-km time trial performance (0.0 ± 1.0%), incremental power (-1.4 ± 3.5%), breathing frequency (-1.6 ± 8.0%; -2.0 ± 7.9%), tidal volume (0.9 ± 7.2%; 2.9 ± 9.4%), breathing RPE (16.1 ± 50.2%, 24.8 ± 43%) or leg RPE (13.4 ± 39.6%; 19.9 ± 43.2%) . Conclusion: These results provide evidence of the performance enhancing effect of four weeks of breathing pattern retraining in cyclists. Furthermore, they suggest breathing pattern can be retrained to exhibit a controlled pattern, without a tachypnoeic shift, during high intensity cycling. Additionally, these results indicate breathing pattern retraining attenuates the respiratory and peripheral perceived effort during incremental exercise. Key words: Breathing pattern disorders, retraining, blood stealing, cycling, performance, power output, respiratory mechanics, perceived exertion, 20km-TT
438

Application of Artificial Neural Networks in Pharmacokinetics

Turner, Joseph Vernon January 2003 (has links)
Drug development is a long and expensive process. It is often not until potential drug candidates are administered to humans that accurate quantification of their pharmacokinetic characteristics is achieved. The goal of developing quantitative structure-pharmacokinetic relationships (QSPkRs) is to relate the molecular structure of a chemical entity with its pharmacokinetic characteristics. In this thesis artificial neural networks (ANNs) were used to construct in silico predictive QSPkRs for various pharmacokinetic parameters using different drug data sets. Drug pharmacokinetic data for all studies were taken from the literature. Information for model construction was extracted from drug molecular structure. Numerous theoretical descriptors were generated from drug structure ranging from simple constitutional and functional group counts to complex 3D quantum chemical numbers. Subsets of descriptors were selected which best modeled the target pharmacokinetic parameter(s). Using manual selective pruning, QSPkRs for physiological clearances, volumes of distribution, and fraction bound to plasma proteins were developed for a series of beta-adrenoceptor antagonists. All optimum ANN models had training and cross-validation correlations close to unity, while testing was performed with an independent set of compounds. In most cases the ANN models developed performed better than other published ANN models for the same drug data set. The ability of ANNs to develop QSPkRs with multiple target outputs was investigated for a series of cephalosporins. Multilayer perceptron ANN models were constructed for prediction of half life, volume of distribution, clearances (whole body and renal), fraction excreted in the urine, and fraction bound to plasma proteins. The optimum model was well able to differentiate compounds in a qualitative manner while quantitative predictions were mostly in agreement with observed literature values. The ability to make simultaneous predictions of important pharmacokinetic properties of a compound made this a valuable model. A radial-basis function ANN was employed to construct a quantitative structure-bioavailability relationship for a large, structurally diverse series of compounds. The optimum model contained descriptors encoding constitutional through to conformation dependent solubility characteristics. Prediction of bioavailability for the independent testing set were generally close to observed values. Furthermore, the optimum model provided a good qualitative tool for differentiating between drugs with either low or high experimental bioavailability. QSPkR models constructed with ANNs were compared with multilinear regression models. ANN models were shown to be more effective at selecting a suitable subset of descriptors to model a given pharmacokinetic parameter. They also gave more accurate predictions than multilinear regression equations. This thesis presents work which supports the use of ANNs in pharmacokinetic modeling. Successful QSPkRs were constructed using different combinations of theoretically-derived descriptors and model optimisation techniques. The results demonstrate that ANNs provide a valuable modeling tool that may be useful in drug discovery and development.
439

Applications of Continuous Spatial Models in Multiple Antenna Signal Processing

Glenn, Dickins, glenn.dickins@dolby.com January 2008 (has links)
This thesis covers the investigation and application of continuous spatial models for multiple antenna signal processing. The use of antenna arrays for advanced sensing and communications systems has been facilitated by the rapid increase in the capabilities of digital signal processing systems. The wireless communications channel will vary across space as different signal paths from the same source combine and interfere. This creates a level of spatial diversity that can be exploited to improve the robustness and overall capacity of the wireless channel. Conventional approaches to using spatial diversity have centered on smart, adaptive antennas and spatial beam forming. Recently, the more general theory of multiple input, multiple output (MIMO) systems has been developed to utilise the independent spatial communication modes offered in a scattering environment.¶ Underlying any multiple antenna system is the basic physics of electromagnetic wave propagation. Whilst a MIMO system may present a set of discrete inputs and outputs, each antenna element must interact with the underlying continuous spatial field. Since an electromagnetic disturbance will propagate through space, the field at different positions in the space will be interrelated. In this way, each position in the field cannot assume an arbitrary independent value and the nature of wave propagation places a constraint on the allowable complexity of a wave-field over space. To take advantage of this underlying physical constraint, it is necessary to have a model that incorporates the continuous nature of the spatial wave-field. ¶This thesis investigates continuous spatial models for the wave-field. The wave equation constraint is introduced by considering a natural basis expansion for the space of physically valid wave-fields. This approach demonstrates that a wave-field over a finite spatial region has an effective finite dimensionality. The optimal basis for representing such a field is dependent on the shape of the region of interest and the angular power distribution of the incident field. By applying the continuous spatial model to the problem of direction of arrival estimation, it is shown that the spatial region occupied by the receiver places a fundamental limit on the number and accuracy with which sources can be resolved. Continuous spatial models also provide a parsimonious representation for modelling the spatial communications channel independent of specific antenna array configurations. The continuous spatial model is also applied to consider limits to the problem of wireless source direction and range localisation.
440

Evaluation of Si-LDMOS transistors for RF Power Amplifier in 2-6 GHz frequency range / Utvärdering av Si-LDMOS transistorer för effektförstärkare i frekvensområdet 2-6 GHz.

Doudorov, Grigori January 2003 (has links)
<p>In this thesis the models of Si-LDMOS transistors have been investigated with Agilent EEsof ADS version 2002a for operation in the 2-6 GHz frequency range. The first one is the Motorola’s (MRF21010) model based on a 30 mm prototype of a Si-LDMOS transistor. The second one is a model based on a 1 mm prototype of Si-LDMOS transistor developed at Chalmers University. Large-signal simulations of Chalmers’ model have demonstrated results, which lead to the conclusion that,this model cannot be efficiently utilised for design for a PA in the 2-6 GHz frequency range. However, additional simulations with reduced Rd (drain losses) show the deep impact of this parameter on the main properties of the designed PA. Hence, it is important to take it into account during new processes of Si-LDMOS as well as to improve the CAD model. The final conclusion regarding Si-LDMOS cannot be made just based on these simulation results, since they are not in accordance with the published ones. The next step should be aimed at improving the model and further investigation of Si-LDMOS to prove their ability to operate in the 2-6 GHz frequency range.</p>

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