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Autonomous-agent based simulation of anti-submarine warfare operations with the goal of protecting a high value unitAkbori, Fahrettin 03 1900 (has links)
Approved for public release, distribution unlimited / The Anti-Submarine Warfare screen design simulation is a program that provides a model for operations in anti-submarine warfare (ASW). The purpose of the program is to aid ASW commanders, allowing them to configure an ASW screen, including the sonar policy, convoy speed, and the number of ships, to gain insight into how these and other factors beyond their control, such as water conditions, impact ASW effectiveness. It is also designed to be used as a training tool for ASW officers. The program is implemented in Java programming language, using the Multi Agent System (MAS) technique. The simulation interface is a Horizontal Display Center (HDC) which is very similar to a MEKO200 class Frigate Combat Information Center's (CIC) HDC. The program uses Extensible Markup Language (XML) files for reading data for program scenarios; parameters are initialized before each run time begins. The simulation also provides all the output data at the end of run time for analysis purposes. The program user's goal, and the purpose of the program, is to decrease the number of successful attacks against surface vessels by changing the configuration parameters of the ASW screen, to reflect sonar policy, convoy speed or number of ships in the simulation. Ongoing use of the program can provide data needed to anticipate required operational needs in future ASW situations. / Lieutenant Junior Grade, Turkish Navy
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Adaptive notch filtering for tracking multiple complex sinusoid signalsWheeler, Paul T. January 2015 (has links)
This thesis is related to the field of digital signal processing; where the aim of this research is to develop features of an infinite impulse response adaptive notch filter capable of tracking multiple complex sinusoid signals. Adaptive notch filters are commonly used in: Radar, Sonar, and Communication systems, and have the ability to track the frequencies of real or complex sinusoid signals; thus removing noise from an estimate, and enhancing the performance of a system. This research programme began by implementing four currently proposed adaptive notch structures. These structures were simulated and compared: for tracking between two and four signals; however, in their current form they are only capable of tracking real sinusoid signals. Next, one of these structures is developed further, to facilitate the ability to track complex sinusoid signals. This original structure gives superior performance over Regalia's comparable structure under certain conditions, which has been proven by simulations and results. Complex adaptive notch filter structures generally contain two parameters: the first tracks a target frequency, then the second controls the adaptive notch filter's bandwidth. This thesis develops the notch filter, so that the bandwidth parameter can be adapted via a method of steepest ascent; and also investigates tracking complex-valued chirp signals. Lastly, stochastic search methods are considered; and particle swarm optimisation has been applied to reinitialise an adaptive notch filter, when tracking two signals; thus more quickly locating an unknown frequency, after the frequency of the complex sinusoid signal jumps.
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Die geldigheid van die "Systems Operations Analysis Package (SOAP84)" by die analisering van geisoleerde seinbeheerde verkeerskruisings17 November 2014 (has links)
M.Ing. (Mechanical Engineering) / The purpose of this study was to investigate the accuracy of SOAP84-simulations of delay and percentage stops at isolated signalized intersections. In the application, capacity was distinguished in terms of lane configuration only. Results at the intersections showed SOAP overestimating both delay and percentage stops by as much as 100%. It is recommended that the same investigations be repeated with more accurate information on the capacity of the intersections.
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Calcium/Calmodulin-Dependent Protein Kinase II Serves as a Biochemical Integrator of Calcium Signals for the Induction of Synaptic PlasticityChang, Jui-Yun January 2016 (has links)
<p>Repetitive Ca2+ transients in dendritic spines induce various forms of synaptic plasticity by transmitting information encoded in their frequency and amplitude. CaMKII plays a critical role in decoding these Ca2+ signals to initiate long-lasting synaptic plasticity. However, the properties of CaMKII that mediate Ca2+ decoding in spines remain elusive. Here, I measured CaMKII activity in spines using fast-framing two-photon fluorescence lifetime imaging. Following each repetitive Ca2+ elevations, CaMKII activity increased in a stepwise manner. This signal integration, at the time scale of seconds, critically depended on Thr286 phosphorylation. In the absence of Thr286 phosphorylation, only by increasing the frequency of repetitive Ca2+ elevations could high peak CaMKII activity or plasticity be induced. In addition, I measured the association between CaMKII and Ca2+/CaM during spine plasticity induction. Unlike CaMKII activity, association of Ca2+/CaM to CaMKII plateaued at the first Ca2+ elevation event. This result indicated that integration of Ca2+ signals was initiated by the binding of Ca2+/CaM and amplified by the subsequent increases in Thr286-phosphorylated form of CaMKII. Together, these findings demonstrate that CaMKII functions as a leaky integrator of repetitive Ca2+ signals during the induction of synaptic plasticity, and that Thr286 phosphorylation is critical for defining the frequencies of such integration.</p> / Dissertation
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DESIGN OF AN INSTRUMENT FOR SOIL MOISTURE AND ABOVE GROUND BIOMASS REMOTE SENSING USING SIGNALS OF OPPORTUNITYBenjamin R Nold (7043030) 15 August 2019 (has links)
Measurements of soil moisture are a crucial component for understanding the global water and carbon cycle, weather forecasting, climate models, drought prediction, and agriculture production. Active and passive microwave radar instruments are currently in use for remote sensing of soil moisture. Signals of Opportunity (SoOp) based remote sensing has recently emerged as a complementary method for soil moisture remote sensing. SoOp reuses general digital communication signals allowing the reuse of allocated wireless communication signal bands for science measurements. This thesis developed a tower based SoOp instrument implementing frequencies in the P-Band and S-Band. Two field campaigns were conducted using this new instrument during the summers of 2017 and 2018 at Purdue's Agronomy Center for Research and Education.
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Impacts of queue jumpers and transit signal priority on bus rapid transitUnknown Date (has links)
Exclusive bus lanes and the Transit Signal Priority are often not effective in saturated peak-traffic conditions. An alternative way of providing priority for transit can be queue jumpers, which allows buses to bypass and then cut out in front of waiting queue by getting an early green signal. Utah Transit authority deployed Bus Rapid Transit system at Salt Lake County, Utah along W 3500 S. This research evaluates the impacts of queue jumpers with TSP on Bus Rapid Transit (BRT) and private vehicular traffic. Four VISSIM models were developed for analysis : Basic scenario, no TSP with queue jumpers, TSP with no queue jumbers, and TSP with queue jumpers. In TQ scenario travel time was reduced between 13.2-19.82% with respect to basic scenario. At the same time, travel time of private traffic increased very little 0.38-3.28%. Two TSP strategies : green extension and red truncation are implemented in this research work. / by R.M. Zahid Reza. / Thesis (M.S.C.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Contribuições da teoria da estimação para modulações digitais que utilizam sinais caóticos. / Contributions of the estimation theory to digital modulations that use chaotic signals.Eisencraft, Marcio 17 April 2006 (has links)
Neste trabalho investiga-se o emprego de técnicas de estimação em sistemas de modulação digital que utilizam sinais caóticos. Inicialmente, aspectos básicos das teorias de sistemas não-lineares e de modulações digitais são revisitados seguidos de técnicas recentemente propostas de modulações digitais caóticas com receptores por correlação coerente, não-coerente e diferencial: o CSK (Chaos Shift Keying), o DCSK (Differential Chaos Shift Keying) e algumas de suas variantes, em especial o FM-DCSK (Frequency Modulated DCSK). Nessa descrição, utiliza-se a notação de equivalente passa-baixas de tempo discreto para facilitar a comparação com modulações digitais convencionais. Deduz-se o limite de Cramér-Rao para a estimação da condição inicial de órbitas caóticas em função de propriedades estatísticas do mapa que as gerou e descrevem-se dois estimadores para elas: o MLE (Maximum Likelihood Estimator) que se aplica a mapas com densidade invariante uniforme e o algoritmo de Viterbi para o qual se apresenta uma generalização a fim de aplicá-lo a uma classe maior de mapas. Por apresentar ganho de estimação maior na faixa de relação sinal-ruído de interesse, este último é utilizado em propostas de sistemas de modulação digital que utilizam estimação de órbitas para detectar o símbolo enviado: o ML-CSK (Maximum Likelihood CSK) modificado para poder usar mapas com densidade invariante não-uniforme, empregando um ou dois mapas e o ML-DCSK (Maximum Likelihood DCSK). Por simulação, avaliou-se o desempenho em termos de taxa de erro desses sistemas sob ruído branco aditivo gaussiano. / In this work, we investigate the use of estimation techniques to digital modulation systems that use chaotic signals. Initially, basic aspects of nonlinear systems and digital modulation theory are reviewed followed by currently proposed techniques of chaotic digital modulation with coherent, noncoherent and differential correlation receivers: CSK (Chaos Shift Keying), DCSK (Differential Chaos Shift Keying) and some of its variants in special FM-DCSK (Frequency Modulated DCSK). These systems are described using a discrete-time lowpass equivalent model to facilitate comparison with conventional digital modulation systems. We derive Cramér-Rao lower bounds for the estimation of the initial condition of chaotic orbits as a function of the statistical properties of the chaos generating map and describe two chaotic orbits estimators: the MLE (Maximum Likelihood Estimator) that applies only to maps with uniform invariant density and the Viterbi algorithm for which a generalization is presented that allows its application to a broader class of maps. Because of the larger estimation gains attained in the signal-to-noise ratio range of interest, the latter is used in proposed digital modulation systems that use orbit estimation to detect the transmitted symbol: ML-CSK (Maximum Likelihood CSK) modified to allow maps with nonuniform invariant density using one map or two maps and ML-DCSK (Maximum Likelihood DCSK). The performance of these systems in terms of symbol error rate is accessed via simulation under additive white gaussian noise perturbations.
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Suplementação de triptofano na atividade elétrica cerebral (EEG) e glicemia de cães da raça Pit Bull / Tryptophan supplementation on brain electrical activity and blood glucose in Pit BullsElmôr, Lucas Domênico 23 January 2009 (has links)
Três cães machos adultos da raça Pit Bull foram utilizados com o intuito de avaliar o efeito da suplementação de triptofano na atividade elétrica cerebral e taxa glicêmica. Os tratamentos foram: A) Dieta base + veículo com placebo (controle); B) Dieta base + veículo com 1,11g de triptofano. Inicialmente os animais passaram por doze dias de fornecimento do tratamento A, destes, cinco dias foram destinados a colheita dos dados. Após três dias de descanso teve início o período de 12 dias de fornecimento do tratamento B, com o aumento de um dia de colheita. Para a colheita de EEG foi utilizado o registro bipolar, sendo o sinal colhido numa freqüência de amostragem de 120 Hz por um período de 20 minutos por dia de colheita. Utilizou-se um glicosímetro portátil para mensurar a glicemia nos tempos 0, 15, 30, 45 minutos, relacionados com o período destinado ao manejo de colheita de EEG. A suplementação de triptofano diminuiu a energia das bandas de freqüências beta, teta, alfa e delta, permitindo sugerir uma modificação na atividade elétrica cerebral. Não houve efeito significativo do fornecimento de triptofano suplementar sobre a glicemia dos cães utilizados neste experimento. / Three adults male Pit Bulls dogs were housed with the intention of evaluating the effects of tryptophan supplementation on brain electrical activity and glicemic curve. The treatments were: A) Basic Diet + Placebo (control); B) Basic Diet + 1,11 g of tryptophan. First the animals were kept for 12 days using the A treatment, with five days of data collecting. After three days off they were kept for 12 days using the B treatment, but with an addition of one day of data collecting. The EEG collecting was made using a bipolar register, and the signal was collected on a 120 Hz sampling frequency for 20 minutes per collecting day. The blood glucose was measured using a portable blood glucose meter on 0, 15, 30 and 45 minutes, related to the EEG collecting period. The Tryptophan supplementation decreased the energy signals of the beta, theta, alpha and delta frequencies, which suggests some modification on the brain electrical activity. There was no effect of the tryptophan supplementation on the glicemic curve.
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[en] THE CONCEPT OF INNOVATION: A TOOL FOR MODELING, ANALYZING AND UNDERSTANDING OF CLIMATOLOGICAL PHENOMENA / [pt] O CONCEITO DE INOVAÇÃO: UMA FERRAMENTA PARA A MODELAGEM, ANÁLISE E COMPREENSÃO DE FENÔMENOS CLIMATOLÓGICOSLUIZ HENRIQUE GUIMARAES DE MACEDO 12 March 2007 (has links)
[pt] A modelagem de fenômenos climatológicos constitui um dos
maiores
desafios enfrentados pela humanidade, impactando toda a
vida do planeta. Muitos
modelos têm sido propostos e muitas ferramentas têm sido
construídas na
tentativa de explicar a dinâmica destes processos e sua
evolução espacial e
temporal. Este trabalho visa oferecer uma contribuição
para a modelagem, análise
e compreensão dos fenômenos climatológicos com base no
conceito da Inovação.
Ao invés de procurar, como os modelos clássicos, a
representação de
comportamentos e relações com base em técnicas
estatísticas, esta pesquisa apóiase
em um novo conceito: a Inovação, que busca o novo, e não o
padrão,
identificando a diferença e modelando o fenômeno a ela
associado O conceito da
Inovação é capaz de caracterizar o fenômeno climatológico,
reconhecendo seu
surgimento, localização, intensidade e duração. A
aplicação do Conceito da
Inovação leva à identificação das conexões globais,
definindo propagações
espaciais e temporais, além de delinear caminhos que
explicam as teleconexões
entre regiões e sua variação ao longo do tempo. Os
resultados obtidos são bastante
promissores, uma vez que conseguem caracterizar os
processos e sua evolução
com uma precisão e eficiência até agora não obtidas pelos
métodos disponíveis.
Além disso, a descoberta e a individualização dos caminhos
que explicam as
teleconexões globais iniciam uma nova classe de
ferramentas para um
conhecimento mais profundo e abrangente de todo o processo
climatológico. / [en] Modeling climatological phenomena is one of the most
intriguing
challenges faced by mankind; the results impact on the
whole planet life. Most
existing models and tools search for the explanation of
these process dynamics
and associated spatial and temporal evolution. This work
targets a contribution to
the modeling, analysis and understanding of climatological
phenomena based on
the Innovation concept. Instead of following the classical
search for statistical
behaviors, the aim is searching for the transient and the
associated impacts. The
Innovation concept is initially applied to the
climatological phenomena,
identifying its birth, location, duration and intensity.
Next, global connections are
identified, defining spatial and temporal propagations.
Finally, global paths and
corresponding variations in time are highlighted and used
to explain global
teleconnections between regions. The obtained results are
promising,
characterizing processes and corresponding evolution
within a precision and
efficiency not offered by existing models. Furthermore,
uncovering the roots of
global teleconnections permits a new class of tools for a
more complete and deep
understanding of the whole climatological environment.
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Transportation operation and safety comparison between unsignalized/signalized offset t-intersections, two-lane roundabout, and modified roundaboutUnknown Date (has links)
Traditional intersections have always caused congestion, delay, and accidents.
There are numerous geometric intersection designs that best fit each situation. This study
performed an operational and safety comparison with unsignalized/signalized offset, Tintersections, a two-lane roundabout, and a modified roundabout to decrease the overall
travel delay and increase the safety using a case study. Using data from a government source, all designs were tested in a calibrated micro simulation model and traffic signals were optimized using a signal optimization platform. Each design was tested with various balancing schemes, left turn percentages, and hourly volumes to determine the failure point. The unsignalized/signalized offset T-intersections, two-lane roundabout, and
modified roundabout were compared by throughputs, travel delay, and travel time. After
analysis, it was determined that the modified roundabout performed the best out of any design. All approaches had minimum travel delay while reducing the number of conflict
points considerably with the modified roundabout. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
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