Dissertations / Theses: 'Short- to medium- range'

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Uribe, Edgar M. "Short To Medium Range Hydrometeorological Forecasting In The Rio Grijalva Basin, Mexico." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/195010.

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The Rio Grijalva basin is the most important basin in Mexico in terms of hydropower production and damages related to extreme rainfall events. This study investigates establishing a short- to medium-range hydrometeorological forecasting system for this basin which comprises a hydrological model and a regional Numerical Weather Prediction Model (NWPM). A physical, distributed, hydrological model (MMS-PRMS) is implemented through the following steps: (1) basin parameterization; (2) interfacing to observed meteorological fields, and (3) parameter optimization. The datasets normally used to parameterize the MMS-PRMS are only available in the US so an alternative methodology for deriving parameters from globally available public datasets was devised. Modeled streamflow calculated by model with the initial parameters was in good agreement with observed streamflow, and optimization yielded even better agreement. The predictive capabilities of the hydrological model was then tested by implementing modeled rainfall and temperature from the North American Regional Reanalysis (NARR), these data being used as a surrogate for those that would be available from a regional NWPM. A significant bias in NARR-rainfall was identified and a novel probabilistic correction procedure devised. This procedure was then extended to provide estimates of uncertainty in the modeled streamflow. Within the calculated uncertainty, the modeled streamflow calculated with these corrected NARR data is in good agreement with modeled streamflow calculated using local meteorological data.

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Biegler, R. "Animal short and medium range navigation and its relationship to associative learning." Thesis, University of Edinburgh, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.641607.

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Learning allows organisms to predict and prepare for events in the environment that are not sufficiently regular that responses to each situation could be genetically hardwired. A possible categorization of what can be learned is as follows: First, an animal may learn that an event is likely to happen. This means learning predictive relations between events, or the probability that an event A occurs with an event B, rather than independently. Second, they may form a representation of the magnitude of the event. Third, animals may learn when an event is likely to happen, the temporal relations between events. Fourth, they may acquire knowledge where something will happen, the spatial relations between events. The question arises whether these distinctions are merely convenient labels or reflect genuine differences between dissociable psychological variables and perhaps processes. The most widely accepted account of animal learning, associative learning theory, assumes that information from all these variables is collapsed into only a single output variable: the strength of an associative link. The theoretical framework of associative learning has predominantly been tested and developed within the domain of learning about predictive relationships between events, weighted by event relevance. The requirements for navigation through space are in some respects quite different. Animals can influence the rate and direction of their passage through space. In the two or three dimensions of space shortcuts and detours become possible. The computation of path length may require vector addition. Possible goals of computation will be considered and compared to data on the contents, acquisition and manipulation of spatial representations. The experimental part of this thesis concentrates on two aspects of information acquisition, landmark stability and blocking. Animals appear to weigh information from different sources according to two different and normally opposed criteria, accuracy and reliability. If discrepancy between two such sources is small, more weight will be given to the more accurate source of information, if the discrepancy is large more to the reliable source.

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Takaishi, Daigo. "Studies on the short and medium range structure of lead-containing oxide glasses." 京都大学 (Kyoto University), 2003. http://hdl.handle.net/2433/148872.

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Biegler, Robert. "Short and medium range navigation and its relationship to cognitive mapping and associative learning." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/21590.

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Learning allows organisms to predict and prepare for events in the environment that are not sufficiently regular that responses to each situation could be genetically hardwired. A possible categorization of what can be learned is as follows: First, an animal may learn that an event is likely to happen. This means learning predictive relations between events, or the probability that an event A occurs with an event B, rather than independently. Second, they may form a representation of the magnitude of the event. Third, animals may learn when an event is likely to happen, the temporal relations between events. Fourth, they may acquire knowledge where something will happen, the spatial relations between events. The question arises whether these distinctions are merely convenient labels or reflect genuine differences between dissociable psychological variables and perhaps processes. The most widely accepted account of animal learning, associative learning theory, assumes that information from all these variables is collapsed into only a single output variable: the strength of an associative link. The theoretical framework of associative learning has predominantly been developed and tested within the domain of learning about predictive relationships between events, weighted by event relevance. The requirements for navigation through space are in some respects quite different. Animals can influence the rate and direction of their passage through space. In the two or three dimensions of space shortcuts and detours become possible. The computation of path length may require vector addition. Possible goals of computation will be considered and compared to data on the contents, acquisition and manipulation of spatial representations. The experimental part of this thesis concentrates on two aspects of information acquisition, landmark stability and blocking. Animals appear to weigh information from different sources according to two different and normally opposed criteria, accuracy and reliability. If discrepancy between two such sources is small, more weight will be given to the more accurate source of information, if the discrepancy is large more to the reliable source. The experiments on landmark stability suggest that manipulating discrepancy throughout training will influence animals' estimate of reliability of a source of information. Other manipulations of this estimate, independent from discrepancy, are also possible. The experiments on blocking have not yielded a simple result. Blocking occurs when the animals were trained with one of two landmark arrays; the other array led to an enhancement of performance when testing with the added landmarks. In addition, previous work on the "geometric module" has been extended and a novel weighting of landmarks by position in the array, rather than distance from a goal, has been found. It is argued that there associative learning can play a role in the creation of most possible representations of space, but that some aspects of navigation involve computations which associative learning is not capable of. Further, consideration of the possible functions of navigation suggests that there is no clear dichotomy between mapping and non-mapping strategies. The features of cognitive maps derived from analogy with physical maps do not form an indivisible category. A navigational system may have only some of these properties, depending on what is required of it. The supposed incompatibility of cognitive mapping and associative learning does not exist, both because there are several navigational strategies that could be considered cognitive mapping processes and because associative learning could contribute to most of them.

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Yehudai, Joseph. "A Study of the Relationship between the Intensity of Short-Range and Medium-Range Capacity Management and the Effectivenesss of Manufacturing Operations." Thesis, North Texas State University, 1988. https://digital.library.unt.edu/ark:/67531/metadc331834/.

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The objective of this study was to examine the relationship between intensity of short-range and medium-range capacity management and effectiveness of manufacturing operations. Data were collected to test the null hypothesis which stated that intensity of short-range and medium-range capacity management does not influence manufacturing effectiveness. Intensity of short-range and medium-range capacity management was indicated by the following variables: (1) production standards; (2) priority determination; (3) delivery dates determination; (4) material requirements planning; (5) routing information; (6) capacity utilization; and (7) backlog measurement. Manufacturing effectiveness was indicated by the following variables: (1) delivery dates performance; (2) lead times; (3) subcontract work; (4) direct labor overtime; (5) direct labor efficiency; (6) plant and equipment utilization; and (7) work in process inventory. The population selected to provide data for this study is the manufacturing firms in the State of Texas with five hundred or more employees. Over 42 percent of the eligible firms responded to a six-page questionnaire. Several multivariate techniques were utilized for data analysis: (1) factor analysis; (2) canonical correlation analysis; (3) bivariate correlation; (4) multiple linear regression; (5) cross-tabulation; and (6) analysis of variance. The results of this research did not adequately support the rejection of the null hypothesis. However, they did definitely identify a distinct group of capacity management intensity variables that influence manufacturing effectiveness in specific cases. Intensity variables were placed in three groups that identified how influential they were over the effectiveness measures. The most influential group included the variables: production standards and material requirements planning. The indication for the manufacturing manager is to concentrate on improvements in these areas. Effectiveness variables were also placed in three groups that identified the level at which the variables were influenced by the intensity variables. The highly influenced group included plant and equipment utilization and delivery dates performance.

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Freese, Adam. "Hard QCD Processes in the Nuclear Medium." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2498.

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The environment inside the atomic nucleus is one of the most fascinating arenas for the study of quantum chromodynamics (QCD). The strongly-interacting nature of the nuclear medium aﬀects the nature of both QCD processes and the quark-gluon structure of hadrons, allowing several unique aspects of the strong nuclear force to be investigated in reactions involving nuclear targets. The research presented in this dissertation explores two aspects of nuclear QCD: firstly, the partonic structure of the nucleus itself; and secondly, the use of the nucleus as a micro-laboratory in which QCD processes can be studied. The partonic structure of the nucleus is calculated in this work by deriving and utilizing a convolution formula. The hadronic structure of the nucleus and the quark-gluon structure of its constituent nucleons are taken together to determine the nuclear partonic structure. Light cone descriptions of short range correlations, in terms of both hadronic and partonic structure, are derived and taken into account. Medium modifications of the bound nucleons are accounted for using the color screening model, and QCD evolution is used to connect nuclear partonic structure at vastly diﬀerent energy scales. The formalism developed for calculating nuclear partonic structure is applied to inclusive dijet production from proton-nucleus collisions at LHC kinematics, and novel predictions are calculated and presented for the dijet cross section. The nucleus is investigated as a micro-laboratory in vector meson photoproduction reactions. In particular, the deuteron is studied in the break-up reaction γd → Vpn, for both the ϕ(1020) and J/ψ vector mesons. The generalized eikonal approximation is utilized, allowing unambiguous separation of the impulse approximation and final state interactions (FSIs). Two peaks or valleys are seen in the angular distribution of the reaction cross section, each of which is due to an FSI between either the proton and neutron, or the produced vector meson and the spectator nucleon. The presence and size of the latter FSI valley/peak contains information about the meson-nucleon interaction, and it is shown that several models of this interaction can be distinguished by measuring the angular distribution for the deuteron breakup reaction.

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Malfait, Wim Jan. "Short- and medium-range order in silicate glasses and melts insights from Raman and NMR spectroscopy and effects on bulk melt properties /." lizenzfrei, 2007. http://e-collection.ethbib.ethz.ch/view/eth:29970.

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Siqueira, Vinícius Alencar. "Previsão de cheias por conjunto em curto a médio prazo: bacia do Taquari-Antas/RS." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/147137.

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A previsão hidrológica possibilita a identificação antecipada de eventos de cheia potencialmente causadores de inundação, o que é de grande importância para a atuação de entidades como a Defesa Civil. Quando se deseja estender a antecedência no tempo em relação a estes eventos, principalmente nos casos onde a bacia de interesse é relativamente rápida, torna-se necessária a incorporação de previsões quantitativas de precipitação (QPF) na modelagem hidrológica, as quais podem ser obtidas a partir de modelos numéricos de previsão do tempo. Entretanto, a falta de acurácia atribuída a estas previsões de chuva, dadas de forma determinística, vem promovendo sua substituição por sistemas de previsão meteorológica por conjunto (EPS - Ensemble Prediction Systems), cuja finalidade é a geração de possíveis estados futuros da atmosfera para considerar as incertezas associadas ao seu estado inicial e às deficiências na representação física dos modelos de previsão do tempo. Neste contexto, o presente estudo teve por objetivo avaliar uma metodologia de previsão de cheias por conjunto na bacia do Taquari-Antas/RS até a cidade de Encantado (19.000 km²), localizada na região Sul do Brasil. Para tanto, foi utilizado o modelo hidrológico MGB-IPH acoplado a diferentes sistemas de previsão, sendo eles: (i) EPS Regional ETA, de curto prazo (até 72 horas) com 5 membros de diferentes parametrizações; (ii) EPS Global ECMWF de médio prazo (até 10 dias) com 50 membros de condições iniciais perturbadas, incluindo perturbação estocástica nos parâmetros de ajuste do modelo e; (iii) Previsão Determinística do Modelo Regional ETA (até 7 dias). A avaliação das previsões consistiu em dois hindcastings distintos, envolvendo uma análise visual de eventos singulares ocorridos em 06/06/2014 e 21/07/2011 além de uma análise estatística no período de Mar/2014 - Nov/2014. Durante a análise visual foi possível identificar, a partir de antecedências de 5 a 6 dias, uma persistência na previsão dada pelo crescente número de membros do conjunto de médio prazo (ECMWF) com superação dos limiares de referência, na medida em que se aproximavam os eventos de cheia. Apesar da grande incerteza na magnitude das previsões hidrológicas para o conjunto de curto prazo, a vazão máxima foi relativamente bem prevista por pelo menos 1 membro em quase todas as antecedências, enquanto que a previsão do timing dos eventos foi considerada de boa confiabilidade. Durante a avaliação estatística foi possível notar uma falta de espalhamento nos conjuntos, com tendência de subestimativa de acordo com o aumento da antecedência. Em uma comparação com previsões determinísticas, as previsões por conjunto demonstraram maior acurácia principalmente até 72 horas de antecedência, com destaque para a maior probabilidade de detecção dos limiares de referência e manutenção de falso alarme a níveis reduzidos. Além disso, verificou-se também que a agregação de previsões efetuadas em tempo anterior naquelas atuais acarreta em ligeira ampliação do espalhamento do conjunto e maiores probabilidades de detecção dos limiares de alerta para os membros mais elevados, apesar da redução no desempenho em termos de acurácia e viés. De forma geral, as previsões por conjunto apresentam potencial para servir como uma informação complementar em sistemas de alerta contra cheias, possibilitando uma melhor preparação dos agentes envolvidos durante a ocorrência destes eventos.
Hydrological forecasting plays an important role for issuing flood warnings, allowing for anticipation and better preparation of authorities at the occurrence of such events. In order to extend lead time in a flood forecast, especially when the catchment response time is relatively fast, it may be useful to couple a hydrological model to quantitative precipitation forecasts (QPF), usually obtained directly from numerical weather prediction (NWP). However, deterministic (i.e. single) QPF are usually referred to many errors and lack of accuracy, mainly caused by uncertainties on initial state of the atmosphere and on physical representation of weather forecasting models. To address these shortcomings, it becomes necessary to take into account the uncertainties associated to rain forecasts, which can be represented by Ensemble Prediction Systems (EPS). The purpose of such systems is to provide different trajectories of the atmosphere by perturbations on its initial condition and on parameterization schemes of the models, generating an ensemble of forecasts that can be used as input to hydrological modelling (HEPS). In this context, the present study aimed to assess a methodology of ensemble flood forecasting on Taquari-Antas basin up to the city of Encantado/RS (19.000 km²), located in southern Brazil. Therefore, the hydrological model MGB-IPH was coupled to different forecasting systems: (i) Short Range EPS ETA (up to 72 hours), a regional model with 5 members of different parameterization schemes; (ii) Medium Range EPS ECMWF (up to 10 days), a global model with 50 members of perturbed initial conditions and stochastic perturbation in the model parameters; (iii) Deterministic ETA Model (up to 7 days). The forecasts were evaluated by two different hindcastings, which includes a visual assessment of singular events occurred on 2011 and 2014 and a statistical analysis for the period between Mar/2014 and Nov/2014. It was possible to identify a forecast persistence on medium-range for the selected events, by the increasing number of members exceeding the reference thresholds from lead times up to 5 - 6 days. On the short range, although large uncertainties in the magnitude of hydrological forecasts were found, the peak discharge was well forecasted - at least for a single member - in nearly all lead times, whereas the prediction of the peak timing was considered reliable. Regarding to statistical evaluation, an inadequate spread in the ensemble was observed from short- to medium-range, with a tendency of underestimation for longer lead times. In a comparison with deterministic forecasts, the ensemble forecasts showed higher accuracy especially up to 72 hours in advance, including highlights on greater probability of detection (POD) above the reference thresholds even with low false alarm rates. It also was found that the a combination of previous forecasts on the recent ones leads to a slight increase of ensemble spread and POD for higher members, despite the performance reduction in terms of accuracy and bias. In summary, the hydrological ensemble forecasts demonstrated a good potential to serve as an additional information within a Flood Alert System.

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Acar, Recep Serdar. "Tracking Short-range Ballistic Targets." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613604/index.pdf.

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The trajectories of ballistic targets are determined significantly by the characteristics that are specific to them. In this thesis, these characteristics are presented and a set of algorithms in order to track short-range ballistic targets are given. Firstly, motion and measurement models for the ballistic targets are formed and then four different filtering techniques are built on these models which are the extended Kalman filter, the unscented Kalman filter, the particle filter and the marginalized particle filter. The performances of these filters are evaluated by making Monte Carlo simulation. The simulations are run using target scenarios obtained according to six degrees-of-freedom trajectory for ballistic targets. Apart from the tracking errors of the filters, drag parameter estimations and the effect of drift calculation on the filter performances are investigated. The estimation results obtained by each filter are discussed in detail by making various simulations.

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Bilgin, Ozan Ozgun. "Short Range Thrusting Projectile Tracking." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614609/index.pdf.

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Short range thrusting projectiles are one of the various threats against armored vehicles and helicopters on the battlefield. Developing a countermeasure for this kind of projectiles is very crucial since they are vast in number and easy to operate on the battlefield. A countermeasure may consist of fire point prediction of the projectile and attack the launcher of it, or it may be the impact point prediction of the projectile and apply a hard-kill counter measure on its way to the ally target. For both of the countermeasure concepts, dynamics and parameters of the projectile must be estimated precisely. In this thesis, dynamic models for thrusting and ballistic flight modes of thrusting projectile are obtained. Three different tracking filters are suggested for precise tracking of the projectiles and their estimation performances are compared. These filters are the Extended Kalman Filter (EKF), the Particle Filter (PF) and the Marginalized Particle Filter (MPF).

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Li, Ketong. "LED CommunicationFor Short Range Wireless." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209172.

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With the huge development of semiconductor lighting technologies, the light emitting diodes (LEDs) are promising technology that eventually replacing traditional incandescent and fluorescent lamps for their high power efficiency, environmental friendliness and long predicted product lifetime. Besides lighting, the advent of high-brightness, fast-switching LED lamps has facilitated LED Communication as a new form of Optical Wireless Communication (OWC) in the visible light spectrum. This thesis study model characteristics of LED communication for indoor optical environment. Based on Matlab and SPICE, an electrical and optical LED communication model is proposed to describe light power's conversion and propagation. In details, our models include (1) models for V-I characteristics and fro small signal behavior, (2) electro-electrical conversion and emitting, (3) optical channel with path loss and noise, (4) receiving model. Moreover, a test and measurement platform for LED communication has been established to validate the proposed model. A case of study on light power distribution within 30cmX30cmX10cm in line-of-sight was implemented by measuring for comparing the theoretical simulation and experimental results. Depending on our model and the case of study, we carried out an inspection of the LED communication performance using On-Off Keying (OOK) signals and a 500 kbps transmission data rate under 10e-3 BER was achieved in our lab.

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Roulin, Emmannuel. "Medium-range probabilistic river streamflow predictions." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209270.

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River streamflow forecasting is traditionally based on real-time measurements of rainfall over catchments and discharge at the outlet and upstream. These data are processed in mathematical models of varying complexity and allow to obtain accurate predictions for short times. In order to extend the forecast horizon to a few days - to be able to issue early warning - it is necessary to take into account the weather forecasts. However, the latter display the property of sensitivity to initial conditions, and for appropriate risk management, forecasts should therefore be considered in probabilistic terms. Currently, ensemble predictions are made using a numerical weather prediction model with perturbed initial conditions and allow to assess uncertainty.

The research began by analyzing the meteorological predictions at the medium-range (up to 10-15 days) and their use in hydrological forecasting. Precipitation from the ensemble prediction system of the European Centre for Medium-Range Weather Forecasts (ECMWF) were used. A semi-distributed hydrological model was used to transform these precipitation forecasts into ensemble streamflow predictions. The performance of these forecasts was analyzed in probabilistic terms. A simple decision model also allowed to compare the relative economic value of hydrological ensemble predictions and some deterministic alternatives.

Numerical weather prediction models are imperfect. The ensemble forecasts are therefore affected by errors implying the presence of biases and the unreliability of probabilities derived from the ensembles. By comparing the results of these predictions to the corresponding observed data, a statistical model for the correction of forecasts, known as post-processing, has been adapted and shown to improve the performance of probabilistic forecasts of precipitation. This approach is based on retrospective forecasts made by the ECMWF for the past twenty years, providing a sufficient statistical sample.

Besides the errors related to meteorological forcing, hydrological forecasts also display errors related to initial conditions and to modeling errors (errors in the structure of the hydrological model and in the parameter values). The last stage of the research was therefore to investigate, using simple models, the impact of these different sources of error on the quality of hydrological predictions and to explore the possibility of using hydrological reforecasts for post-processing, themselves based on retrospective precipitation forecasts.

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La prévision des débits des rivières se fait traditionnellement sur la base de mesures en temps réel des précipitations sur les bassins-versant et des débits à l'exutoire et en amont. Ces données sont traitées dans des modèles mathématiques de complexité variée et permettent d'obtenir des prévisions précises pour des temps courts. Pour prolonger l'horizon de prévision à quelques jours – afin d'être en mesure d'émettre des alertes précoces – il est nécessaire de prendre en compte les prévisions météorologiques. Cependant celles-ci présentent par nature une dynamique sensible aux erreurs sur les conditions initiales et, par conséquent, pour une gestion appropriée des risques, il faut considérer les prévisions en termes probabilistes. Actuellement, les prévisions d'ensemble sont effectuées à l'aide d'un modèle numérique de prévision du temps avec des conditions initiales perturbées et permettent d'évaluer l'incertitude.

La recherche a commencé par l'analyse des prévisions météorologiques à moyen-terme (10-15 jours) et leur utilisation pour des prévisions hydrologiques. Les précipitations issues du système de prévisions d'ensemble du Centre Européen pour les Prévisions Météorologiques à Moyen-Terme ont été utilisées. Un modèle hydrologique semi-distribué a permis de traduire ces prévisions de précipitations en prévisions d'ensemble de débits. Les performances de ces prévisions ont été analysées en termes probabilistes. Un modèle de décision simple a également permis de comparer la valeur économique relative des prévisions hydrologiques d'ensemble et d'alternatives déterministes.

Les modèles numériques de prévision du temps sont imparfaits. Les prévisions d'ensemble sont donc entachées d'erreurs impliquant la présence de biais et un manque de fiabilité des probabilités déduites des ensembles. En comparant les résultats de ces prévisions aux données observées correspondantes, un modèle statistique pour la correction des prévisions, connue sous le nom de post-processing, a été adapté et a permis d'améliorer les performances des prévisions probabilistes des précipitations. Cette approche se base sur des prévisions rétrospectives effectuées par le Centre Européen sur les vingt dernières années, fournissant un échantillon statistique suffisant.

A côté des erreurs liées au forçage météorologique, les prévisions hydrologiques sont également entachées d'erreurs liées aux conditions initiales et aux erreurs de modélisation (structure du modèle hydrologique et valeur des paramètres). La dernière étape de la recherche a donc consisté à étudier, à l'aide de modèles simples, l'impact de ces différentes sources d'erreur sur la qualité des prévisions hydrologiques et à explorer la possibilité d'utiliser des prévisions hydrologiques rétrospectives pour le post-processing, elles-même basées sur les prévisions rétrospectives des précipitations.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Dunbar, Robin M. "Short range electromagnetic wave communication underwater." Thesis, Heriot-Watt University, 1986. http://hdl.handle.net/10399/1957.

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Dixon, Roger Steven. "Short Range Air Defense Defense Planner." Thesis, Monterey, California. Naval Postgraduate School, 1990. http://hdl.handle.net/10945/30638.

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Approved for public release, distribution is unlimited
The Short Range Air Defense (SHORAD) Defense Planner, or SDP, is a prototype defense planning and simulation tool. It is designed to aid and train Army Air Defense Officers in the tasks of: (1) planning the air defense for a given static asset; and (2) positioning short range air defense weapon systems in the best possible way. A prototype system has been constructed which allows the Air Defender to position his asset to defend, with the system then performing a heuristic search, and displaying four possible attack routes that could be used by attacking aircraft to reach the map region containing the asset. The user may then position Towed-Vulcan, Stinger, and Chaparral weapon systems where he feels they will provide the best defense of the asset, or request the system to position four Vulcans, four Stinger, or four of each Vulcan and Stinger in defense of the asset. The user can then choose any vehicle that he, or the system, positioned and be able to see a 3D representation of what the gunner in that vehicle would see. He is also able to maneuver that vehicle over the 3D terrain to select the best possible defensive position from the gunner's point of view. Both the Towed-Vulcan, and the Chaparral weapon systems, have bee modeled in 3D for use in the SDP prototype system.

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Kohls, Nicholas Everett. "Software Defined Radio Short Range Radar." BYU ScholarsArchive, 2021. https://scholarsarchive.byu.edu/etd/9027.

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High cost is a current problem with modern radar systems. Software-defined radios (SDRs) offer a possible solution for low-cost customizable radar systems. An SDR is a radio communi- cation system where, instead of the traditional radio components implemented in hardware, many of the components are implemented in software on a computer or embedded system. Although SDRs were originally designed for wireless communication systems, the firmware of an SDR can be configured into a radar system. With new companies entering the market, various types of low- cost SDRs have emerged. This thesis explores the use of a LimeSDR-Mini in a short-range radar through open software tools and custom code. The LimeSDR-Mini is successfully shown to detect targets at a short range. However, due to the instability of the LimeSDR-Mini, the consistent detection of a target is not possible. This thesis shows how the LimeSDR is characterized and how timing synchronization and instability issues are mitigated. The LimeSDR-Mini falls short of operating reliable in a radar system and other SDR boards need to be explored as viable options. Test setups using coaxial cables and test setups using antennas in an outdoor environment show the instability of the LimeSDR-Mini. The transmitter and the receiver are asynchronous. The timing difference varies slightly from run to run, which results in issues that are exacerbated in a short-range radar. The bleed-through signal is the signal leakage from the transmitter to the receiver. The bleed-through signal prevents the detection of targets at a short-range. Feed-through nulling is a signal processing technique used to eliminate the bleed-through signal so that short- range targets can be detected. The instability of the LimeSDR-Mini reduces the effectiveness of feed-through nulling techniques.

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Scherrer, Simon Scherrer Simon Scherrer Simon. "Skill prediction for medium-range weather forecasts." Zürich : ETH, Eidgenössische Technische Hochschule Zürich, Institute for Atmospheric and Climate Science IACETH, 2002. http://e-collection.ethbib.ethz.ch/show?type=dipl&nr=46.

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Warren, Steven W. MATHEMATICAL MODELS WEATHER FORECASTING WEATHER PREDICTIONS MODELS REDUCTION PHYSICS OCEANOGRAPHY POWER REGRESSION ANALYSIS NAVY COMPARISON FORECASTING THESES. "Ensemble forecasting techniques in medium-range forecasting /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA267443.

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Thesis (M.S. in Meteorology and Physical Oceanography) Naval Postgraduate School, March 1993.
Thesis advisor(s): Wendell A. Nuss. "March 1993." Page 66 is missing (which includes Fig. 21 a-b). Bibliography: p. 109. Also available online.

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Warren, Steven W. "Ensemble forecasting techniques in medium-range forecasting." Thesis, Monterey, California. Naval Postgraduate School, 1993. http://hdl.handle.net/10945/39902.

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Approved for public release; distribution is unlimited.
A continuing trend in numerical weather prediction (NWP) is the desire for reduced model forecast error. Developments in NWP such as advanced computing power and improved model physics and analysis methods have been successful in lowering error but are potentially limited The regression method of ensemble forecasting is used to further reduce mean forecast error when compared to individual model forecast performances. A statistical regression scheme is utilized to achieve an optimum combination fitting of the National Meteorological Center, the European Centre for Medium-Range Weather Forecasts, and the U.S. Navy Fleet Numerical Oceanography Center forecast models. The performance of the regression model is evaluated for 72-h and 108-h prediction cycles through statistical and subjective comparisons with the individual models and an equally weighted ensemble model at the surface and at 500 hPa. The regression model is shown to produce gains through the reduction of systematic error present in the individual model forecasts...

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Al-Haifi, Yahia Mohamed Hasan. "Short range GPS single epoch ambiguity resolution." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309824.

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Bernardino, Nelson Fernando Rei. "The nonlocal model of short-range wetting." Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/1349.

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Recently, a Nonlocal Model was proposed that seems to overcome difficulties of the fluctuation theory of 3D wetting. In this thesis we explore this model in detail, laying the foundations for its use. We show how the model can be derived from a microscopic Hamiltonian by a careful coarse graining procedure, based on a previous recipe proposed by Fisher and Jin. These authors obtained a model with a position dependent stiffness that has a dramatic effect on the wetting transition, driving the transition first-order. Our improved method does not have an explicit position dependent stiffness, rather the substrate-interface interaction is described by a binding potential functional with an elegant diagrammatic expansion. We then check the robustness of the structure of the Nonlocal Model using perturbation theory to study a more general microscopic Hamiltonian. The model is robust to such generalisations, whose only relevant effect is the change of the values of the coefficients of the Nonlocal Model. The same remarks are valid for the inclusion of a surface field. The generalised model still has the same structure, albeit with different coefficients. Another important extension is a longer-range substrate-fluid interaction. We generalise the model to be able to deal with these and also with a bulk field. The results for the particular case of an exponentially decaying substrate potential reveal interesting consequences for the transition, which can provide a direct test of the Nonlocal Model. We finalise with a chapter proving that the Nonlocal model obeys a sum-rule for complete wetting.

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Lin, Ismael. "Combining dense short range sensors and sparse long range sensors for mapping." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-223572.

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Mapping is one of the main components of autonomous robots, and consist in the construction of a model of their environment based on the information gathered by different sensors over time. Those maps will have different attributes depending on the type of sensor used for the reconstruction. In this thesis we focus on RGBD cameras and LiDARs. The acquired data with cameras is dense, but the range is short and the construction of large scale and consistent maps is more challenging. LiDARs are the exact opposite, they give sparse data but can measure long ranges accurately and therefore support large scale mapping better. The thesis presents a method that uses both types of sensors with the purpose of combine their strengths and reduce their weaknesses. The evaluation of the system is done in an indoor environment, and with an autonomous robot. The result of the thesis shows a map that is robust in large environments and has dense information of the surroundings.
Kartläggning är en av huvudkomponenterna för autonoma robotar, och består av att bygga en modell av miljön utifrån informationen som samlats in av olika sensorer över tid. Dessa kartor kommer att ha olika attribut beroende på vilken typ av sensor som används för rekonstruktionen. I denna avhandling är fokus på RGBD-kameror och LiDARs. Datan från kameror är kompakt men kan bara mäta korta sträckor och det är utmanande att konstruera storskaliga och konsistenta kartor. LiDARs är exakt motsatta, de ger gles data men kan mäta långa avstånd noggrant och stödjer därför storskalig kartering bättre. Avhandlingen presenterar en metod som använder båda typerna av sensorer i syfte att kombinera deras styrkor och minska svagheterna. Utvärderingen av systemet sker i en inomhusmiljö och med en autonom robot. Resultatet av avhandlingen visar en karta som är robust i stora miljöer och har tät information om omgivningen.

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Cuhadaroglu, Burak. "Range/doppler Ambiguity Resolution For Medium Prf Radars." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609372/index.pdf.

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Range and Doppler measurement of targets for medium PRF radars is handicapped by folding and blind regions. This requires use of multiple PRFs and a resolver algorithm. The aim of the thesis is to develop various algorithms for the task and estimate their performance. Four different range and Doppler resolver algorithms and a test software is developed by using Matlab ®
GUI and their performances due to the selected radar parameters in a multi- target environment are examined.

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Bürger, Gerd. "Dynamically vs. empirically downscaled medium-range precipitation forecasts." Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2010/4493/.

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For three small, mountainous catchments in Germany two medium-range forecast systems are compared that predict precipitation for up to 5 days in advance. One system is composed of the global German weather service (DWD) model, GME, which is dynamically downscaled using the COSMO-EU regional model. The other system is an empirical (expanded) downscaling of the ECMWF model IFS. Forecasts are verified against multi-year daily observations, by applying standard skill scores to events of specified intensity. All event classes are skillfully predicted by the empirical system for up to five days lead time. For the available prediction range of one to two days it is superior to the dynamical system.

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Oyekunle, Abiola Taiwo. "Wireless Short Range Communication Technologies for Home Automation." Thesis, Halmstad University, Halmstad Embedded and Intelligent Systems Research (EIS), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-4017.

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A modern home contains varieties of electronic equipment and systems like: TV, Hi-fi equipment, central heating systems, fire alarm systems, security alarm systems, lighting systems etc. Enabling these devices to communicate is the first step towards the long-predicted smart home, but this requires communication standards to follow. It can be anticipated that the technology must be wireless in order for such network to be feasible. Large set of standards are present for as well wired as wireless communication in between such devices, but today no standard communication interface available.

The goal of this project is to survey available standards for short-range wireless communication, and to evaluate and compare their capabilities to become a general standard for home automation. The evaluation must take such aspects as security, range, network architecture and the heterogeneous set of devices into consideration. Furthermore, this thesis proposes how to interconnect the home network to the external network for remote supervision and control.

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Söderkvist, Jonas. "Evaluation of Wireless Techniques for Short-Range Communication." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2045.

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On radar level gauges currently shipped by Saab Rosemount, some adjustments of the unit's parameters has to be performed in the field. Presently, this is a cumbersome procedure; the operator has to be very close to the gauge and he either has to carry with him a bulky configuration unit or use a basic control unit on the gauge. A wireless solution, where a portable device and a receiver replace the control unit, would both allow the operator to work from a distance and eliminate the need for the bulky device.

The most conspicuous restraint for such a solution is a very low allowed power dissipation. The reason for this is that some gauges do not have a separate power supply, but are fed directly off the communication bus. A viable solution should also be commercially available and robust enough to operate in an industrial environment.

To meet these requirements both a theoretical and a practical assessment was conducted, where the two techniques for wireless communication, IrDA, and Bluetooth, was given special consideration. As for the portable device, the market for hand-held computers was investigated and ultimately a PDA from Palm was selected for this project. Together with this PDA, a prototype for each of the two wireless techniques was tested to ascertain their performance with respect to power dissipation, communication range, and communication robustness.

This investigation revealed that Bluetooth could be used over a much greater distance than IrDA and it did also provide a more robust solution overall. IrDA is nonetheless also a competent technique, and has its primary advantage in terms of much lower power dissipation compared to Bluetooth.

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Swift, Melinda. "A model for the short range nuclear force /." Title page, contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09PH/09phs976.pdf.

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Thesis (Ph. D.)--University of Adelaide, Dept. of Physics and Mathematical Physics, 1993.
Copies of author's previously published articles inserted. Includes bibliographical references (leaves 103-108).

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Rowan, David Glenn. "Theoretical studies of disordered short-range spin models." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299226.

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Lawlor, Sean. "Detecting convoys in networks of short-range sensors." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121245.

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Detecting groups of vehicles traveling together as a convoy is an important problem in military and law enforcement applications. License plate recognition sensors are an emerging technology which can be used to solve this problem. The sensors are deployed throughout road networks across the world and meta-data about the vehicles passing in front of each sensor is collected. These provide discrete, irregularly sampled, time series information about where vehicles are traveling. This thesis proposes a method to solve the problem of detecting convoys utilizing irregularly sampled time series information about objects moving between sensors. The system presented in this thesis is a hypothesis test to determine if a pair of objects is traveling in a convoy or independently. The models for the hypothesis test are based on a semi-Markov process model for an object traveling between sensor locations which are the states in the Markov process. The system is analyzed utilizing a real dataset which shows that it does in fact detect pairs of objects which appear to be traveling together in a convoy. It is then analyzed utilizing a simulated dataset containing an equal number of pairs traveling in convoys as well as independently and the performance on the number of accurate detections as well as false detections is summarized. The system described solves the problem of detecting convoys utilizing limited-range sensors, such as license plate recognition sensors. The system presented is represented as a general system determining if "objects" are moving together in a path that appears tied together versus independently. This allows the system to have future applications to other fields that is not just license plate recognition information of vehicular movements. It can be generalized to other problems of determining similar paths in Markov chain environments.
Détecter des groupes de véhicules se déplaçant ensemble en convoi est un problème important dans les domaines militaires et policiers. Les capteurs capables de reconnaître les plaques d'immatriculation forment un nouveau type de capteurs qui peuvent être utilisés pour résoudre ce problème. Ces capteurs sont déployés tout au long de réseaux routiers à travers le monde et des métadonnées sur les véhicules traversant devant ceux-ci sont recueillies. Ces métadonnées procurent des informations discrètes et irrégulièrement échantillonnées sous forme de séries temporelles indiquant la direction de déplacement des véhicules. Cette thèse propose une méthode qui utilise des séries temporelles irrégulièrement échantillonnées d'information à propos d'objets en déplacement entre capteurs afin de résoudre le problème de détection de convois.Le système présenté dans cette thèse crée un test d'hypothèse afin de déterminer si une paire d'objets se déplacent dans un convoi ou indépendamment. Les modèles pour le test d'hypothèse sont basés sur un semi-processus de Markov pour un objet qui se déplace entre les emplacements de capteurs, emplacements qui forment les états du processus de Markov. Le système est analysé avec une banque de données réelles et démontre qu'il peut effectivement détecter des paires d'objets qui semblent se déplacer conjointement. Le système est ensuite analysé avec une banque de données artificielles contenant autant de paires d'objets formant une escorte que de paires se déplaçant indépendamment et sa performance sur le nombre de détections exactes ainsi que fausses est résumée.Le système décrit ci-haut résout le problème de détection de convois par utilisation de capteurs à portée réduite tels que les lecteurs de plaque d'immatriculation automatisés. Le système décrit est traité sous la forme d'un système général qui distingue entre des objets se déplaçant ensemble sur une voie donnée où ils semblent liés et des objets se déplaçant indépendamment. Cette description laisse place à de futures applications dans d'autres domaines qui ne comptent pas nécéssairement sur des lecteurs de plaques d'immatriculation pour obtenir des données sur le mouvement de véhicules. Le système peut-être généralisé à d'autres problèmes de détection de cheminement dans des environnements utilisant des chaînes de Markov.

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Kersop, Stefanus Jacobus. "Short range reconnaissance unmanned aerial vehicle / S.J. Kersop." Thesis, North-West University, 2009. http://hdl.handle.net/10394/9171.

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Unmanned aerial vehicles (UAVs) have been used increasingly over the past few years. Special Forces of various countries utilise these systems successfully in war zones such as Afghanistan. The biggest advantage is rapid information gathering without endangering human lives. The South African National Defence Force (SANDF) also identified the need for local short range aerial reconnaissance and information gathering. A detailed literature survey identified various international players involved in the development of small hand-launch UAV systems. Unfortunately, these overseas systems are too expensive for the SANDF. A new system had to be developed locally to comply with the unique requirements, and budget, of the SANDF. The survey of existing systems provided valuable input to the detailed user requirement statement (URS) for the new South African development. The next step was to build a prototype using off-the-shelf components. Although this aircraft flew and produced good video images, it turned out to be unreliable. The prototype UAV was then replaced with a standard type model aircraft, purchased from Micropilot. Some modifications were needed to ensure better compliance with the URS. Laboratory and field tests proved that the aircraft can be applied for aerial images, within range of 10 km from the ground control station (GCS). The major limitation is that it can only fly for 40 minutes. Furthermore, the airframe is not robust, needing repairs after only 15 flights. Although the system has shortcomings, it has already been used successfully. It is expected that improved battery technologies and sturdier light-weight materials will further help to improve the system beyond user specifications.
Thesis (MIng (Electrical Engineering))--North-West University, Potchefstroom Campus, 2010.

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McCreesh, Zita M. "Short range, RF telemetry for physiological temperature acquisition." Thesis, University of Ulster, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262271.

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Crespo, Manuel. "Wind turbine monitoring using short-range Doppler radar." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8420/.

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This thesis summarises the research done on the feasibility of detecting and automatically classifying wind turbine faults using a short-range radar. Two main areas are included in the thesis: the theoretical and experimental analysis of wind turbine blade radar signatures in the near-field and the classification of wind turbine structural faults using machine learning algorithms. In the former, a new theoretical framework has been developed which extends the current far-field models and includes a mathematical and experimental analysis of simple flat blades as well as complex curved blades. The latter area comprises the analysis of the experimental results obtained using faulty wind turbine blades and methods of classifying these faults. This last task has been done in time and frequency domains using, respectively, the signals Statistical Parameters and the Principal Component Analysis algorithm for features extraction. The classification bas been performed employing the k-Nearest Neighbours algorithm. Finally, an Artificial Neural Network has been used as a more powerful classification tool in both domains.

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Hong, Seung Ho. "Short-range Structure of Nematic Bent-core Mesogens." Kent State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=kent1271255435.

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Kim, Hong-Sun. "2.4GHz CMOS Receivers for short-range wireless applications /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486399451959422.

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Ong, Gin Kaijing. "Short-to-medium term dengue forecast in Singapore." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/126991.

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Thesis: S.M., Massachusetts Institute of Technology, Computation for Design and Optimization Program, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 103-116).
Dengue fever is currently the fastest spreading mosquito-borne disease in the world, and a substantial public health problem due to its geographic spread, intensity, and resulting economic impact. The disease is endemic in Singapore, and has caused multiple outbreaks of unprecedented magnitude in the last two decades. Without a specific antiviral agent or a safe, effective and affordable vaccine for the disease, vector control remains the most effective way to control dengue transmission. The objective of this thesis is to develop spatially resolved accurate short-to-medium term dengue forecast systems, informed by mechanistic understanding of dengue transmission from previous field studies. Such systems could improve our understanding of factors that influence the transmission of dengue fever in Singapore, and potentially be used by government agencies for the planning of targeted vector control measures.
Data on dengue persistence, housing types, rainfall and seasonality was used to predict weekly dengue incidence at a housing level (i.e. dengue incidence in the high-rise and low-rise subzone groups) and at a residential subzone level. For both spatial resolutions, a separate multiple linear regression submodel was constructed for each forecast horizon of 1 to 12 weeks. Our housing-level model was able to achieve good predictions up to 6 weeks in advance, with predictive R² greater than 0.5 and total explained variance greater than 60%, but our subzone-level model was not as successful. At a housing level, we found that rainfall, housing type and seasonality predictors became relatively more important at longer forecast horizons. We also found that increased rainfall months before implies lower dengue incidence, and that rainfall influences seasonal variability in dengue incidence to a large degree.
The low-rise subzone group was also associated with higher dengue incidence than the high-rise subzone group. These findings support hypotheses from previous field studies on the roles of rainfall and urban hydrology in shaping the spatiotemporal distribution of dengue in Singapore. These risk factors of dengue could be included in current operational forecast systems to improve their predictive performance.
by Gin Kaijing Ong.
S.M.
S.M. Massachusetts Institute of Technology, Computation for Design and Optimization Program

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Casas, Villalba Isabel. "Statistical inference in continuous-time models with short-range and/or long-range dependence." University of Western Australia. School of Mathematics and Statistics, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0133.

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The aim of this thesis is to estimate the volatility function of continuoustime stochastic models. The estimation of the volatility of the following wellknown international stock market indexes is presented as an application: Dow Jones Industrial Average, Standard and Poor’s 500, NIKKEI 225, CAC 40, DAX 30, FTSE 100 and IBEX 35. This estimation is studied from two different perspectives: a) assuming that the volatility of the stock market indexes displays shortrange dependence (SRD), and b) extending the previous model for processes with longrange dependence (LRD), intermediaterange dependence (IRD) or SRD. Under the efficient market hypothesis (EMH), the compatibility of the Vasicek, the CIR, the Anh and Gao, and the CKLS models with the stock market indexes is being tested. Nonparametric techniques are presented to test the affinity of these parametric volatility functions with the volatility observed from the data. Under the assumption of possible statistical patterns in the volatility process, a new estimation procedure based on the Whittle estimation is proposed. This procedure is theoretically and empirically proven. In addition, its application to the stock market indexes provides interesting results.

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Fan, Zhiyuan. "Optical Activity of Chiral Nanomaterials: Effects of Short Range and Long Range Electromagnetic Interactions." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1394998277.

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Ebrecht, Eila. "NMR-Untersuchungen zur Medium Range Order in binären Alkalisilicatgläsern." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola&quot, 2009. http://nbn-resolving.de/urn:nbn:de:swb:105-1221949.

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Gegenstand dieser Arbeit ist die Untersuchung der Medium Range Order in binären Alkalisilicatgläsern mittels 29Si-Festkörper-NMR-Spektroskopie. Die Medium Range Order kann durch die Qn,jklm-Verknüpfungen beschrieben werden. Die experimentelle Ermittlung der Qn,jklm-Verknüpfungen ermöglicht Aussagen über die kontrovers diskutierte topologische Verteilung der Qn-Gruppen im Glas, d.h. ob im Glas eine homogene oder inhomogene Qn-Verteilung vorliegt. Es wurden 29Si-angereicherte binäre Natrium- und Lithiumsilicatgläser verschiedener Zusammensetzungen NMR-spektroskopisch untersucht. Die Anreicherung mit dem 29Si-Isotop führte einerseits zu einer signifikanten Verbesserung des Signal / Rausch-Verhältnisses der 1D-Spektren und ermöglichte andererseits die Anwendung von 2D-NMR-Experimenten. Aus der Kombination der verschiedenen NMR-Methoden konnten Erkenntnisse über die Qn,jklm-Verknüpfungen gewonnen werden. In allen untersuchten Gläsern wurden Abweichungen von einer homogenen Qn-Verteilung gefunden.

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Ebrecht, Eila. "NMR-Untersuchungen zur medium range order in binären Alkalisilicatgläsern." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=96915304X.

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Rovira, Esteva Muriel. "Short-range order in disordered phases using neutron diffraction." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/283110.

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Neutron diffraction is a powerful technique that allows to probe the structure of disordered phases across a variety of length scales. However, due to the inherent complexity of these disordered hases, the analysis of the information contained in the experimental data is not obvious. In this work, a few alternative methods are presented that allow to make the most of the neutron diffraction measurements as well as the molecular configurations obtained from molecular dynamics simulations or data modelling. They mainly consist in a Bayesian approach to fit the molecular structures measured with neutron diffraction, and a multidimensional analysis of the molecular structure probability distribution functions obtained from simulations or data modelling techniques, instead of the standard averaging over many variables. These methodologies are then applied to the structural investigation of several disordered systems in order to answer a series of open questions: the origin of the liquid-liquid transition in trans-1,2-dichloroethene (C2Cl2H2), the extreme fragility of 1,1,2,2-tetrachloro-1,2-difluoroethane's orientational glass (F-112, C2Cl4F2), the local density paradox in carbon tetrachloride (CCl4), and the roles of steric and electrostatic interactions in the short range order of the liquids of quasitetrahedral molecules, particularly trichlorobromomethane (CBrCl3) and dibromodichloromethane (CBr2Cl2). Additionally, a concise summary of the theoretical framework for neutron diffraction of disordered systems, as well as the practicalities of the experimental setup and the necessary data treatment, are also included to provide interested researchers with a self-contained overview on the topic.
La difracció de neutrons és una tècnica molt potent que permet sondar l'estructura de fases desordenades en un ventall d'escales de longitud. Tanmateix, degut a la complexitat inherent d'aquestes fases desordenades, l'anàlisi de la informació que es desprèn de les dades experimentals no és evident. En aquest treball es presenten diversos mètodes alternatius que permeten treure el màxim profit de les mesures de difracció de neutrons, així com de les configuracions moleculars obtingudes en simulacions de dinàmica molecular o del modelatge de les dades. Aquests mètodes consisteixen principalment en un enfocament bayesià en l'ajust de les estructures moleculars mesurades amb difracció de neutrons, i en una anàlisi multidimensional de les funcions de distribució de probabilitat de l'estructura molecular obtingudes en simulacions o tècniques de modelatge de dades, en comptes del mitjanat de diverses variables estàndard. Aquestes metodologies s'apliquen a la investigació de diversos sistemes desordenats per tal de resoldre una sèrie de qüestions obertes: l'origen de la transició líquid-líquid en el trans-1,2-dicloroetà (C2Cl2H2), l'extrema fragilitat del vidre orientacional del 1,1,2,2-tetracloro-1,2-difluoroetà (F-112, C2Cl4F2), la paradoxa de la densitat local en el tetraclorur de carboni (CCl4), i els rols de les interaccions estèrica i electrostàtica en l'ordre de curt abast de líquids de molècules quasitetraèdriques, en particular el triclorobromometà (CBrCl3) i el dibromodiclorometà (CBr2Cl2). Addicionalment, també s'hi inclou un breu repàs del marc teòric de la difracció de neutrons en sistemes desordenats, així com dels aspectes pràctics de l'equip experimental i del tractament de dades necessari, per tal que els investigadors interessats disposin d'una visió general completa sobre tema.

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Valero, Lopez Ari Yakov. "Design of frequency synthesizers for short range wireless transceivers." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/108.

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The rapid growth of the market for short-range wireless devices, with standards such as Bluetooth and Wireless LAN (IEEE 802.11) being the most important, has created a need for highly integrated transceivers that target drastic power and area reduction while providing a high level of integration. The radio section of the devices designed to establish communications using these standards is the limiting factor for the power reduction efforts. A key building block in a transceiver is the frequency synthesizer, since it operates at the highest frequency of the system and consumes a very large portion of the total power in the radio. This dissertation presents the basic theory and a design methodology of frequency synthesizers targeted for short-range wireless applications. Three different examples of synthesizers are presented. First a frequency synthesizer integrated in a Bluetooth receiver fabricated in 0.35μm CMOS technology. The receiver uses a low-IF architecture to downconvert the incoming Bluetooth signal to 2MHz. The second synthesizer is integrated within a dual-mode receiver capable of processing signals of the Bluetooth and Wireless LAN (IEEE 802.11b) standards. It is implemented in BiCMOS technology and operates the voltage controlled oscillator at twice the required frequency to generate quadrature signals through a divide-by-two circuit. A phase switching prescaler is featured in the synthesizer. A large capacitance is integrated on-chip using a capacitance multiplier circuit that provides a drastic area reduction while adding a negligible phase noise contribution. The third synthesizer is an extension of the second example. The operation range of the VCO is extended to cover a frequency band from 4.8GHz to 5.85GHz. By doing this, the synthesizer is capable of generating LO signals for Bluetooth and IEEE 802.11a, b and g standards. The quadrature output of the 5 - 6 GHz signal is generated through a first order RC - CR network with an automatic calibration loop. The loop uses a high frequency phase detector to measure the deviation from the 90° separation between the I and Q branches and implements an algorithm to minimize the phase errors between the I and Q branches and their differential counterparts.

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Byrne, David N., John C. Palumbo, T. V. Orum, and Robin J. Rathman. "Identifying Short-Range Migration by the Sweet Potato Whitefly." College of Agriculture, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/221474.

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Populations of the sweet potato whitefly, Bemisia tabaci, have been shown to consist of both migratory and trivial flying morphs. The behavior of these forms as part of the process of short-range migration needed to be examined under field conditions. Insects were marked in a field of cantaloupes using fluorescent dust. During the first growing season traps, used to collect living whiteflies, were placed along 16 equally spaced transects (22.5° apart) radiating out from the field to a distance of up to 0.6 miles. Wind out of the northeast consistently carried migrating whiteflies to traps placed along transects in the southwestern quadrant because cold air drainages dictate wind direction during early morning hours. For this reason, during the second season traps were laid out in a rectangular grid extending 3 miles to the southwest of the marked field. If dispersal was entirely passive or wind directed patterns could be described using a diffusion model. Statistical examination of the data, however, demonstrate that the distribution on all days was patchy. Traps in the immediate vicinity of the marked field caught more whiteflies than the daily median. Large numbers were also collected from around the periphery of the grid. Whiteflies were far less prevalent in the grid's center. As a result, the distribution of captured whiteflies can be described as bimodal. These patterns confirm behavior observed in the laboratory, i.e., a portion of the population are trivial fliers that do not engage in migration and are consequently captured in traps near the field and a portion initially ignore vegetative cues and fly for a period of time before landing in distant traps. This second population comprises the second peak in the model that appeared 1.6 miles from the marked field. On a localized level, 1.6 miles seems to be how far whiteflies move in a day. Earlier studies indicate that whiteflies only fly one day.

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Li, Chuan. "Short-range ultrasonic communications in air using capacitive transducers." Thesis, University of Warwick, 2009. http://wrap.warwick.ac.uk/3161/.

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This thesis describes the development and characterisation of an airborne ultrasonic communication system using electrostatic transducers. Initially, digital modulation schemes, namely OOK, BFSK and BPSK were used for transmission of a digital binary stream across an air gap of 0 – 1.2 m. BPSK was found to be the most favourable solution for the lowest BER performance. BFSK, being the second best among the three was simpler to implement and was more robust against synchronisation errors. Later, to further improve bandwidth efficiency, several M-nary modulations, namely QPSK, MSK and 8PSK were used. The data rate reached 800 kbps when 8PSK was used. An ultrasonic keyboard using BFSK were developed as a simple application. A real-time communication system was also developed using a PXI system and LabVIEW, with which broadband data communication and real-time performance analysis was realised. The channel response of the ultrasonic communication link was modelled, with the characteristic of ultrasonic absorption in air, transducer response, and spatial field response. The latter was found to be crucial factor when the transreceivers were not aligned in parallel. The results recorded at various distances were in good agreement with those predicted using the system model developed. Several equalisation techniques were looked at in this thesis, to combat the selective attenuation response for longer-range propagation, and its effectiveness has been compared to using multicarrier modulation. This thesis has also looked at multipath interference, which is likely to be effect the performance in future applications. It shows that by using spread spectrum techniques, multipath interference can be tackled in an ultrasonic system.

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43

NEUPANE, USHA. "PERFORMANCE ANALYSIS OF LOW-POWER, SHORT-RANGE WIRELESS TRANSCEIVERS." Master's thesis, University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4169.

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To address the various emerging standards like BluetoothTM, Home RF, Wi-fiTM (IEEE 802.11), ZigBeeTM etc., in the field of wireless communications, different transceivers have been designed to operate at various frequencies such as 450 MHz, 902-920 MHz, 2.4 GHz, all part of designated ISM band. Though, the wireless systems have become more reliable, compact and easy to develop than before, a detailed performance analysis and characterization of the devices should be done. This report details the performance analysis and characterization of a popular binary FSK transceiver TRF6901 from Texas Instruments. The performance analysis of the device is done with respect to the TRF/MSP430 demonstration and development kit.
M.S.E.E.
Department of Electrical and Computer Engineering
Engineering and Computer Science
Electrical Engineering

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44

Rowell, D. P. "Short range rainfall forcasting in the West African Sahel." Thesis, University of Reading, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381920.

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Cleary, Robert. "Spatial frequency selective processes in short range motion perception." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.237562.

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Grimit, Eric P. "Probabilistic mesoscale forecast error prediction using short-range ensembles /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/10064.

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Mohr, Richard Frank Jr. "Quantum mechanical three-body problem with short-range interactions." Connect to this title online, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1050007430.

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Thesis (Ph. D.)--Ohio State University, 2003.
Title from first page of PDF file. Document formatted into pages; contains xiii, 182 p.; also includes graphics Includes bibliographical references (p. 181-182). Available online via OhioLINK's ETD Center

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Zhang, Bin. "Searching for Short Range Correlations Using (e,e'NN) Reactions." Washington, D.C : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Energy Research ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2003. http://www.osti.gov/servlets/purl/824928-2353Al/native/.

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Thesis; Thesis information not provided; 1 Feb 2003.
Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-38" "DOE/ER/40150-2762" Bin Zhang. 02/01/2003. Report is also available in paper and microfiche from NTIS.

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Zhang, Bin Ph D. Massachusetts Institute of Technology. "Searching for short range correlations using (e,e'NN) reactions." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29938.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2003.
Includes bibliographical references (p. 211-215).
Electron induced two nucleon knockout reactions (e,e'pp) and (e,e'np) were performed for 3He, 4He and 12C nuclei with incident energies of 2.261 GeV and 4.461 GeV using the CLAS detector at Jefferson Lab. Events with missing momenta lower than the Fermi level and missing energies smaller than the pion threshold were studied. The residual system was assumed to be a spectator and the process was considered as a quasi-free knockout of an NN pair. The cross sections for 15 different reactions were presented as functions of the initial relative momentum per nucleon of the NN pair. The data showed that the initial momentum extends up to 800 MeV/c with considerable strength. The cross sections for 3He(e,e'pp)n were compared to the calculations of J.M. Laget. It was found that the final state interactions (FSI) and the meson exchange currents (MEC) dominate the cross sections and the short range properties of the NN pair were substantially undermined. However, the node of the S state wave function of the pp pair at around 400 MeV/c initial momentum starts to be recognizable in the 4.461 GeV data. The data and the theory suggest that with higher momentum transfers, especially in the region of XBj > 1, the competing processes such as FSI and MEC will be less important and the detailed study of the short-range properties of nucleons inside nuclei will be more desirable.
by Bin Zhang.
Ph.D.

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Artiles, Oswaldo. "Multinucleon Short-range Correlation Model for Nuclear Spectral Functions." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3384.

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The main goal of the research presented in my dissertation was to develop a theoretical model for relativistic nuclear spectral functions at high missing momenta and removal energies based on the multi-nucleon short-range correlation (SRC) model. The nuclear spectral functions are necessary for the description of high energy nuclear processes currently being studied at different labs such as JLAB, LHC and FNAL. The model followed the effective Feynman diagrammatic approach in order to ac-count for the relativistic effects important in the SRC domain. In addition to the two-nucleon (2N) SRC with center of mass motion contribution, the contribution of the three-nucleon SRCs to the spectral functions was also derived. The latter was modeled based on the assumption that the 3N SRCs are a product of two sequential short range nucleon-nucleon (NN) interactions. The nuclear spectral functions models were derived from two theoretical frameworks for evaluating covariant Feynman diagrams: In the first, referred to as the virtual nucleon approximation, the Feynman diagrams were reduced to the time ordered non-covariant diagrams by evaluating the nucleon spectators in the SRC at their positive energy poles, neglecting explicitly the contribution from vacuum diagrams. In the second approach, referred to as the light-front approximation, the boost invariant nuclear spectral function was formulated in the light-front reference frame in which case the vacuum diagrams are kinematically suppressed and the bound nucleon is described by its light-front variables such as momentum fraction, transverse momentum and invariant mass. On the basis of the derived nuclear spectral functions, the corresponding computational models were developed from which the numerical estimates of the SRC spectral functions, the SRC momentum distributions, and the SRC density matrices were obtained.

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