Dissertations / Theses: 'Windows speed'

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Tsegaye, Melekam Asrat. "A comparative study of the Linux and windows device driver architecture with a focus on IEEE1394 (high speed serial bus) drivers." Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1004829.

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New hardware devices are continually being released to the public by hardware manufactures around the world. For these new devices to be usable under a PC operating system, device drivers that extend the functionality of the target operating system have to be constructed. This work examines and compares the device driver architectures currently in use by two of the most widely used operating systems, Microsoft’s Windows and Linux. The IEEE1394 (high speed serial bus) device driver stacks on each operating system are examined and compared as an example of a major device driver stack implementation, including driver requirements for the upcoming IEEE1394.1 bridging standard.

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Shivarudraiah, Ranjitha. "STCP: A New Transport Protocol for High-Speed Networks." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/cs_theses/67.

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Transmission Control Protocol (TCP) is the dominant transport protocol today and likely to be adopted in future high‐speed and optical networks. A number of literature works have been done to modify or tune the Additive Increase Multiplicative Decrease (AIMD) principle in TCP to enhance the network performance. In this work, to efficiently take advantage of the available high bandwidth from the high‐speed and optical infrastructures, we propose a Stratified TCP (STCP) employing parallel virtual transmission layers in high‐speed networks. In this technique, the AIMD principle of TCP is modified to make more aggressive and efficient probing of the available link bandwidth, which in turn increases the performance. Simulation results show that STCP offers a considerable improvement in performance when compared with other TCP variants such as the conventional TCP protocol and Layered TCP (LTCP).

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Hawkins, Mikhel E. "High speed target tracking using Kalman filter and partial window imaging." Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/16709.

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Svobodová, Lenka. "Nádraží VRT letiště Brno Tuřany." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225430.

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Main topic of this Masters Thesis is design of railway station for high speed line railway. Building site is situated in East Moravian region in the district of Brno-Tuřany. The building is designed as a detached two-storey object standing on the bridge over the railway. Mass of the building consists of two trimmed blocks which are mutually mirrored. The mass of both parts of the building is pervaded by illuminating stripe. Its shape is also based on the shape of trimmed block and rises over the surrounding surfaces. There are placed vertical paths in the stripes. It helps passengers in orientation because these are visible even from the outside of the building. This arrangement of individual masses symbolizes both direction of the arrival of trains to the station. There is placed arrival and departure hall in the middle of the object. Its height is similar to the height of the object itself. The hall is surrounded by the service facilities of the railway station situated on two floors. The supporting structure is made of steel. Both peripheral housing and roof are supported by the frame construction consisting of planar lattice beams. Construction of the façade is composed of frame system Wicona. The peripheral housing is tiled with panels of expanded metal.

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Berg, Allison M. "The feasibility of sodar wind profile measurements from an oceanographic buoy." Thesis, (37 MB), 2006. http://handle.dtic.mil/100.2/ADA471871.

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Thesis (M.S.)--Massachusetts Institute of Technology at Woods Hole Oceanographic Institution, 2006.
"September 2006." Description based on title screen as viewed on June 8, 2010. DTIC Descriptor(s): Doppler Radar, Wind Velocity, Sound Ranging, Doppler Sonar, Buoys, Measurement, Motion, Oceanographic Equipment, Theses DTIC Identifier(s): Doppler Sodar, Sodar (Sound Detection and Ranging), ASIS Includes bibliographical references (leaf 75). Also available in print.

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Pang, Wan-kai. "Time series analysis of meteorological data : wind speed and direction /." [Hong Kong] : University of Hong Kong, 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13456933.

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Ndzukuma, Sibusiso. "Statistical tools for wind energy generation." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1020627.

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In this study we conduct wind resource assessment to evaluate the annual energy production of a wind turbine. To estimate energy production of a wind turbine over a period of time, the power characteristics of the wind turbine are integrated with the probabilities of the wind speed expected at a chosen site. The first data set was obtained from a wind farm in Denmark. We propose several probability density functions to model the distribution of the wind speed. We use techniques from nonlinear regression analysis to model the power curve of a wind turbine. The best fit distribution model is assessed by performing numeric goodness–of–fit measures and graphical analyses. Johnson’s bounded (SB) distribution provides the best fit model with the smallest Kolmogorov–Smirnov (K-S) test statistic . 15. The four parameter logistic nonlinear regression (4PL) model is determined to provide the best fit to the power curve data, according to the Akaike Information Criterion (AIC) and the Bayesian Information Criterion (BIC). The estimated annual energy yield is compared to the actual production of the wind turbine. Our models underestimate the actual energy production by a 1 difference. In Chapter Six we conduct data processing, analyses and comparison of wind speed distributions using a data set obtained from a measuring wind mast mounted in Humansdorp, Eastern Cape. The expected annual energy production is estimated by using the certified power curve as provided by the manufacturer of the wind turbine under study. The commonly used Weibull distribution is determined to provide the best fit distribution model to our selected models. The annual energy yield is estimated at 7.33 GWh, with a capacity factor of 41.8 percent.

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彭運佳 and Wan-kai Pang. "Time series analysis of meteorological data: wind speed and direction." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B30425979.

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Mason, Matthew S. (Matthew Stephen). "Simulation of downburst wind fields." Phd thesis, School of Civil Engineering, 2009. http://hdl.handle.net/2123/7719.

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Schmidlin, Thomas W. Hammer Barbara King Paul Ono Yuichi Miller L. Scott Thumann Gregory. "Unsafe at any (wind). speed? Testing the stability of motor vehicles in severe winds." [Emmitsburg, MD : National Emergency Training Center], 2002. http://ams.allenpress.com/archive/1520-0477/83/12/pdf/i1520-0477-83-12-1821.pdf.

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Pelletier, Robert G. (Robert Gordon). "Multifractal characterization of aircraft-based measurements of turbulence and passive scalar fields within the surface boundary layer." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22788.

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This thesis represents the first large-scale, systematic study to use the double trace moment (DTM) technique in order to characterize the universal multifractal nature of aircraft-based measurements of wind velocity and several passive scalar concentrations under a variety of ambient conditions. Power-law scaling behaviour was demonstrated for the examined fields, from the smallest accessible measurement scales up to at least 250 km, right through the "mesoscale gap" postulated by the standard model of atmospheric dynamics. DTM results indicate remarkable stability in the estimates of the multifractality index, $ alpha$, and the codimension of mean singularity, $C sb1$, for wind velocity measured under different conditions of surface type, time of year, and measurement height within the surface boundary layer. Estimates for $ rm CO sb2, H sb2O, and O sb3$ were largely dominated by the wind velocity statistics as expected, but slightly sensitive to measurement height and moderately sensitive to significant changes in the underlying surface. Results showed that all of the fields examined may be classified as "unconditionally hard" multifractals, which is consistent with previously-published results for ground-based wind velocity measurements. It was demonstrated using probability distribution and multifractal analyses that ensemble statistical moments above approximately second-order can be expected to diverge for all examined fields due to the extremely singular nature of the fields at sub-resolution scales, and that the currently-employed quasi-local aircraft based sampling strategy is capable of reliably characterizing the statistical behaviour of the examined fields up to this physically-imposed limit. (Abstract shortened by UMI.)

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Schillinger, Douglas J. "Wind speed estimates and precipitation detection using ambient sound in the ocean." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ55540.pdf.

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Thoren, Mark W. "The Development of a New Anemometer for Measuring High Speed Winds on Mount Washington, New Hampshire." Fogler Library, University of Maine, 2001. http://www.library.umaine.edu/theses/pdf/ThorenMW2001.pdf.

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EL-Nimri, Salem. "AN IMPROVED MICROWAVE RADIATIVE TRANSFER MODEL FOR OCEAN EMISSIVITY AT HURRICANE FORCE SURFACE WIND SPEED." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2523.

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An electromagnetic model for predicting the microwave blackbody emission from the ocean surface under the forcing of strong surface winds in hurricanes is being developed. This ocean emissivity model will be incorporated into a larger radiative transfer model used to infer ocean surface wind speed and rain rate in hurricanes from remotely sensed radiometric brightness temperature. The model development is based on measurements obtained with the Stepped Frequency Microwave Radiometer (SFMR), which routinely flys on the National Oceanic and Atmospheric Administration's hurricane hunter aircraft. This thesis presents the methods used in the wind speed model development and validation results for wind speeds up to 70 m/sec. The ocean emissivity model relates changes in measured C-band radiometric brightness temperatures to physical changes in the ocean surface. These surface modifications are the result of the drag of surface winds that roughen the sea surface, produce waves, and create white caps and foam from the breaking waves. SFMR brightness temperature measurements from hurricane flights and independent measurements of surface wind speed are used to define empirical relationships between microwave brightness temperature and surface wind speed. The wind speed model employs statistical regression techniques to develop a physics-based ocean emissivity model dependent on geophysical parameters, such as wind speed and sea surface temperature, and observational parameters, such as electromagnetic frequency, electromagnetic polarization, and incidence angle.
M.S.E.E.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering

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Wang, Yu 1964. "Measurements and multifractal analysis of turbulent temperature and velocity near the ground." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23433.

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High frequency turbulent temperature measurements were performed above clipped grass in the lower atmospheric surface layer in conjunction with three-dimensional turbulent velocities. Measurements were also made of turbulent temperature inside a corn canopy and at the canopy top. The 500Hz temperature time series were collected over periods of varying intervals, to a maximum of 24 hours.
The multifractal analysis was performed on several datasets. First scaling properties of the temperature and the velocity fields were examined. Our results suggest that scaling is not observed throughout the entire range but on different regimes. The physically related regimes corresponding to the clipped grass experiment include the inertial subrange, the trend for diurnal peak, and a range between them, all together featuring the existence of the hourly gap. In the canopy experiment, except for the above feature, the effects of the presence of plant objects are also reflected by the presence of two regimes different from those for clipped grass field.
The double trace moment technique was performed on the inertial subrange of the temperature and velocity fields measured over clipped grass to obtain the parameters characterizing the multifractal fields. The variability of the parameters with the atmospheric stability was investigated and no apparent difference between stable and unstable conditions was found. The results reveal that those fields are universal multifractals with the characteristic parameters $ alpha$ near 1.7 and C$ sb1$ ranging from 0.04 to 0.12, implying that the fields can be modeled by a log-Levy process with unbounded singularities. We also found that the critical moment q$ rm sb{s}$ for the multifractal phase transition is close to 4.

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Moodley, Kirshnee. "The fitting of statistical distributions to wind data in coastal areas of South Africa." Thesis, Nelson Mandela Metropolitan University, 2013.

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Coastal South African cities like Port Elizabeth are said to have a strong potential for wind energy. This study aims to model wind data in order to be able assess the power potential belonging to a given site. The main challenge in modelling wind direction data is that it is categorized as circular data and therefore requires special techniques for handling that are different from usual statistical samples. Statistical tools such as descriptive measures and distribution fitting, were re-invented for directional data by researchers in this field. The von Mises distribution is a predominant distribution in circular statistics and is commonly used to describe wind directions. In this study, the circular principles described by previous researchers were developed by using the statistical software, Mathematica. Graphical methods to present the wind data were developed to give an overview of the behaviour of the winds in any given area. Data collected at Coega, an area near Port Elizabeth, South Africa, was used to illustrate the models which were established in this study. Circular distributions were fit to the directional data in order to make appropriate conclusions about the prevailing wind directions in this area.

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James, Carl S. "Evaluation of COAMPS performance forecasting along coast wind events during a frontal passage." Thesis, Monterey, California. Naval Postgraduate School, 2005. http://hdl.handle.net/10945/2281.

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Approved for public release, distribution is unlimited
Performance of high resolution mesoscale models has been in a continuous state of refinement since their inception. Mesoscale models have become quite skillful in forecasting synoptic scale events such as mid-latitude cyclones. However, atmospheric forcing becomes a much more complicated process when faced with the challenge of forecasting near topography along the coastline. Phenomena such as gap flows, blocked flow winds and low level stratification become important to predictability at these scales. The problem is further complicated by the dynamics of a frontal passage event. The skill of mesoscale models in predicting these winds is not as well developed. This study examines several forecasts by the Coupled Ocean Atmospheric Mesoscale Prediction System (COAMPS) during frontal passage events for the Winter of 2003-2004. An attempt is made to characterize the predictability of the wind speed and direction both before and after frontal passage along the California coast. Synoptic forcing during this time is strong due to the effects of the mid-latitude cyclones propagate across the Pacific. The study's results indicate that the wind field predictability is subject to several consistent errors associated with the passage of fronts over topography. These errors arise due to difficulty in the model capturing weak thermal advection events and topographic wind funneling. The deficiencies in model representation of topography contributes to these errors.
Lieutenant, United States Navy

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Leite, Emerson Batista. "Análise comparativa entre respostas de torre de transmissão sujeita a carregamentos obtidos através do método do vento sintético e da norma NBR 6123/88." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1350.

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Há diversos procedimentos para determinação dos carregamentos de vento. A norma NBR 6123/88 pode ser utilizada para determinação desses carregamentos e consequentes esforços para dimensionamento de estruturas. Entretanto há procedimentos não normativos que podem contribuir para determinação desses mesmos carregamentos. Um deles, que é empregado no presente trabalho, é o método do vento sintético. O objetivo desse trabalho é o de fazer uma análise comparativa entre as respostas obtidas na estrutura sujeita aos carregamentos dinâmicos, obtidos através do método do vento sintético, e as respostas obtidas com carregamentos estáticos gerados a partir de considerações da norma NBR 6123/88 – Forças devidas ao vento em edificações. A estrutura em estudo é uma torre de transmissão de energia elétrica, que é modelada no programa computacional RSTAB da Dlubal (DLUBAL, 2015), para determinação de suas características dinâmicas. Os carregamentos dinâmicos do vento para o método do vento sintético são gerados através de um algoritmo, utilizando-se do programa computacional Mathcad Prime, versão 3.0. Os carregamentos estáticos e dinâmicos são lançados na estrutura para determinação de deslocamentos, esforços internos axiais e reações de apoio. Os resultados comparados demonstram que a abordagem que considera carregamentos gerados a partir da NBR 6123/88 é a mais conservadora, com valores de grandezas que excedem em até 132% valores obtidos a partir do método do vento sintético.
There are several procedures to determine the wind loadings. The Brazilian code NBR 6123/88 can be used to determine these loadings and the internal forces for structural design. However, there are non-normative procedures that may contribute to determining those same loads. One of them, which is used in this work, is the method of synthetic wind. The aim of this study is to make a comparative analysis of the responses obtained for the structure when subjected to dynamic loads, obtained through the synthetic wind method, and the responses obtained with static loads generated from considerations of NBR 6123/88 - Forces due to the wind on buildings. The structure under study is a power transmission tower, which is modeled in the software program RSTAB, developed by Dlubal, to determine its dynamic characteristics. Using the software Mathcad Prime 3.0 the dynamic wind loads are generated by an algorithm for the wind synthetic method. Static and dynamic loads are applied to in the structure to determine displacements, axial internal forces and support reactions. The compared results show that the approach that considers loadings generated from the NBR 6123/88 is the most conservative, with magnitude values that exceed up to 132% values obtained from the synthetic wind method.

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Wannberg, Veronica Elaine. "Quantitative Uncertainty of Chemical Plume Transport in Low Wind Speeds Using Measured Field Data and Stochastic Modeling." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2570.pdf.

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Riddell, Kevin Donald Alexander. "Design, testing and demonstration of a small unmanned aircraft system (SUAS) and payload for measuring wind speed and particulate matter in the atmospheric boundary layer." Thesis, Arts and Science, 2014. http://hdl.handle.net/10133/3416.

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The atmospheric boundary layer (ABL) is the layer of air directly influenced by the Earth’s surface and is the layer of the atmosphere most important to humans as this is the air we live in. Methods for measuring the properties of the ABL include three general approaches: satellite-based, ground- based and airborne. A major research challenge is that many contemporary methods provide a restricted spatial resolution or coverage of variations of ABL properties such as how wind speed varies across a landscape with complex topography. To enhance our capacity to measure the properties of the ABL, this thesis presents a new technique that involves a small unmanned aircraft system (sUAS) equipped with a customized payload for measuring wind speed and particulate matter. The research presented herein outlines two key phases in establishing the proof-of-concept of the payload and its integration on the sUAS: (1) design and testing and (2) field demonstration. The first project focuses on measuring wind speed, which has been measured with fixed wing sUASs in previous research, but not with a helicopter sUAS. The second project focuses on the measurement of particulate matter, which is a major air pollutant typically measured with ground- based sensors. Results from both proof-of-concept projects suggest that ABL research could benefit from the proposed techniques.

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Furieri, Luca. "Geometric versus Model Predictive Control based guidance algorithms for fixed-wing UAVs in the presence of very strong wind fields." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/11872/.

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The recent years have witnessed increased development of small, autonomous fixed-wing Unmanned Aerial Vehicles (UAVs). In order to unlock widespread applicability of these platforms, they need to be capable of operating under a variety of environmental conditions. Due to their small size, low weight, and low speeds, they require the capability of coping with wind speeds that are approaching or even faster than the nominal airspeed. In this thesis, a nonlinear-geometric guidance strategy is presented, addressing this problem. More broadly, a methodology is proposed for the high-level control of non-holonomic unicycle-like vehicles in the presence of strong flowfields (e.g. winds, underwater currents) which may outreach the maximum vehicle speed. The proposed strategy guarantees convergence to a safe and stable vehicle configuration with respect to the flowfield, while preserving some tracking performance with respect to the target path. As an alternative approach, an algorithm based on Model Predictive Control (MPC) is developed, and a comparison between advantages and disadvantages of both approaches is drawn. Evaluations in simulations and a challenging real-world flight experiment in very windy conditions confirm the feasibility of the proposed guidance approach.

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De, Man Pierre. "Contrôle actif du rayonnement acoustique des plaques: une approche à faible autorité." Doctoral thesis, Universite Libre de Bruxelles, 2004. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211180.

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L'objectif de cette thèse consiste en l'étude d'une stratégie de contrôle actif à faible autorité avec comme application le contrôle actif du rayonnement acoustique d'une plaque. Depuis l'essor du contrôle actif, son application aux problèmes acoustiques et vibracoustiques a été investiguée par de nombreux chercheurs, exploitant soit la théorie du contrôle optimal, soit des approches originales basées plus particulièrement sur la physique. Des notions spécifiques au contrôle vibroacoustique ont été développées comme, par exemple, les modes radiatifs pouvant caractériser le rayonnement acoustique d'une plaque d'une manière adaptée au contrôle.

Le contrôle actif à faible autorité, pour lequel le Laboratoire de Structures Actives a développé une expertise dans le domaine de l'amortissement et du contrôle actif des vibrations, est une solution attractive par sa simplicité de mise en oeuvre. Le plus souvent implémenté sous la forme d'un contrôle décentralisé constitué de boucles indépendantes, le contrôle à faible autorité bénéficie de certaines garanties de stabilité et de robustesse.

Bien que notre stratégie de contrôle puisse s'appliquer à n'importe quel type de plaque, l'application considérée dans ce travail a été motivée par le contexte socio-économique actuel en rapport avec les nuisances acoustiques. Il était en effet intéressant d'évaluer la stratégie de contrôle pour le problème de la transmission acoustique d'un vitrage. La stratégie de contrôle se divise en deux étapes. Tout d'abord le développement d'un capteur unique destiné à fournir une mesure représentative du bruit rayonné par une plaque en basse fréquence. Deux capteurs de vitesse volumétrique (l'un discret, l'autre distribué) ont ainsi été développés et évalués expérimentalement.

Ensuite, une procédure d'optimisation de l'emplacement d'un ensemble d'actionneurs pilotés en parallèle est proposée. L'objectif de cette phase d'optimisation est de forcer la réponse fréquentielle du système à posséder les propriétés d'un système colocalisé. La stratégie de contrôle est ensuite évaluée sur deux structures expérimentales.

/ This thesis is concerned with a low authority active control strategy applied to the sound radiation control of a baffled plate. Since the development of active control ,numerous researchers have studied its application to acoustical or vibroacoustical problems using either the modern control theory or other methods based rather on the understanding of the physics of the problem. Vibroacoustical active control has lead to the definition of radiation modes allowing to describe the radiated sound of a plate in an appropriate manner for active control purposes.

Low autorithy control (LAC), for which the Active Structures Laboratory has gained an expertise for active vibration control applications is an interesting solution for its implementation simplicity. Most of the time it consists of several decentralized control loops, and benefits from guaranteed stability and robustness properties. Although our control strategy can be applied to any kind of plates, the application considered here has been motivated by the present socio-economical context related to noise annoyances. The active control strategy has been applied the problem of the sound transmission loss of glass plates (windows). This strategy is in two steps :first a volume velocity sensor is developed as to give a measure representative of the radiated sound at low frequencies.

Two sensors have been developed (one discrete and one distributed) and experimentally tested. Next, an optimisation strategy is proposed which allow to locate on the plate a set of several actuators driven in parallel. The goal of this optimisation task is to obtain an open-loop frequency response which behave like a collocated system. The control strategy is finally evaluated on two plate structures.
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished

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Du, Preez Chrisna Barbara. "A mesoscale investigation of the sea breeze in the Stellenbosch winegrowing district." Diss., Pretoria : [s.n.], 2007. http://upetd.up.ac.za/thesis/available/etd-02092007-093317.

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Kavický, Martin. "Analýza vlivu velikosti okna a zpoždění na efektivitu TCP spojení." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218327.

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Content of master’s thesis is description field of Sliding window and it’s expansion algorithms, witch are Slow start, Congestion avoidance, Fast Retransmit and Fast Recovery algorithm. Thereinafter is described creation of model in Opnet Modeler’s simulation area. In this simulation area was analyzed reactions of average transfer speed onto variance of data size, lost ratio, latency in short and long time slot and variance of receiver’s buffer size. In last section of this document is method design witch makes it possible of transfer speed control through the use of receiver’s buffer size dynamic setting.

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Silva, Tiago Polizer da. "Anemômetro ultrassônico unidimensional baseado em correlação cruzada." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/1929.

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Este trabalho descreve o desenvolvimento de um medidor de velocidade de vento aplicando técnicas da teoria de erros, como a correlação cruzada, bem como sensores de ultrassom. Ele pode ser utilizado em encanamentos, onde se busca obter a velocidade de fluídos, em estações climáticas, em aeroportos, no momento de se aplicar pesticidas assim como em fazendas eólicas, onde o conhecimento da velocidade do vento é necessário, dentre outras aplicações. O sistema desenvolvido é composto pela placa de desenvolvimento de0-nano, uma placa de circuito impresso (PCB) para aquisição de sinais e dois pares de sensores de ultrassom. A PCB também possui circuitos para excitação dos sensores de ultrassom bem como comunicação com o PC para armazenamento dos sinais amostrados. A teoria de erros foi discutida e os resultados do protótipo foram analisados utilizando métodos probabilísticos necessários para verificar a incerteza. Dentro da FPGA da placa de0-nano foi desenvolvido um sistema baseado no processador NIOS, o qual foi construído através da ferramenta QSYS. Além disso, blocos em VHDL foram desenvolvidos para interfaceamento do sistema com o PC. Um pequeno túnel de vento foi construído e um anemômetro de mão foi adquirido para validar o protótipo. Simulações foram realizadas no Microsoft Excel 2007 para comparar a correlação cruzada dada pelo protótipo e a teoria. É comum que DSPs e Microprocessadores estejam dentro de medidores de velocidade do vento, no entanto um sistema desenvolvido com FPGA aumenta a velocidade de processamento devido ao paralelismo. Blocos descritos em VHDL podem ser facilmente replicados dentro da FPGA e existe uma grande coleção de bibliotecas, literatura extensiva e exemplos de código para o NIOS. Com isso há um menor tempo de desenvolvimento de um protótipo/sistema e há facilidade de desenvolver um System on Chip (SoC) de sistemas baseados em FPGA, reduzindo os custos de um futuro produto comercial.
This work describes the development of one axis wind speed measurement equipment applying error theory techniques, as the cross correlation, and ultrasound sensors. It can be used in tubes, where fluid speed knowledge is needed, climate stations, airports, in the moment of applying pesticides and in wind farms, where wind speed knowledge is necessary. The built prototype is a connected set of a de0-nano development board, a signal acquisition printed circuit board and two pairs of ultrasound sensors. The PCB also has circuits for ultrasound sensors exciting and PC communications to store the sampled signals. The error theory was discussed and the prototype's results were developed using probabilistic methods needed to verify the uncertainty. Inside de0-nano board FPGA chip, a system based in NIOS processor was developed and built through QSYS tool. There are some blocks described in VHDL for PCB interfacing. A small wind tunnel was built and a hand anemometer was acquired to validate the proposed system. Simulations were done in Microsoft Excel 2007 to compare the cross correlation given by the prototype and the theory. It is common DSPs and microprocessors inside this type of equipments to measure wind speed, but a system developed with a FPGA increases the processing speed due to parallelism. Blocks described in VHDL can be easily replicated inside the FPGA and there is a large collection of libraries, extensive literature and code examples for NIOS. Thereby there are small system/prototype developing times and there is an easy development of a System on Chip (SOC) of FPGA based systems, reducing the costs for a future commercial product.

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Sakamoto, Beatriz Sayuri. "Análise de confiabilidade estrutural utilizando o método FORM com múltiplos modos de falha para edifício alto submetido à ação do vento." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/2667.

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O presente trabalho tem por objetivo aplicar a análise de confiabilidade estrutural a um edifício alto submetido à ação do vento considerando o conforto humano na avaliação dos modos de falha. Para isso, foram consideradas como variáveis aleatórias: a velocidade máxima do vento no topo do edifício cuja distribuição de probabilidade é a distribuição de Gumbel para máximos e o módulo de elasticidade do concreto com modelo de probabilidade normal. Realizou-se a análise para dois modos de falha: o deslocamento excessivo no topo do edifício, com base na NBR 15575-2/2013, e a aceleração máxima para verificação do conforto humano de acordo com a NBR 6123/2013. Posteriormente, foi realizada uma análise conjunta dos modos de falha aplicados em série. O método utilizado foi o FORM – First Order Reliability Method com algoritmo HLRF, implementado em ambiente Matlab, para o edifício teórico CAARC. Verificou-se grandes discrepâncias entre a probabilidade de falha para os dois modos considerados. Para a aceleração máxima, encontrou-se valores práticos de ponto de projeto e probabilidade de falha. No entanto, o deslocamento horizontal de 3 centímetros resultou em uma probabilidade de falha extremamente alta para valores de velocidade de vento baixos, concluindo-se que, para o edifício alto do problema, o limite normativo tende a ser facilmente extrapolado. À vista disso, o parâmetro de deslocamento horizontal baseado na altura total do edifício também foi estudado. Tal análise resultou em uma probabilidade de falha maior que a da aceleração, no entanto, apresentando valores de ponto de projeto consistentes.
The present work aims to apply structural reliability analysis to a tall building subjected to wind load considering human comfort in the evaluation of failure modes. For this purpose, the following random variables were considered: the maximum wind speed at the top of the building whose probability distribution is the Gumbel distribution for maximum and the modulus of elasticity of concrete with normal distribution. The analysis was conducted for two failure modes: excessive displacement on the top of the building, which is based on NBR 15575/2013, and the maximum acceleration for verification of the human comfort according to NBR 6123/2013. A joint analysis of failure modes applied in series was performed. The method used was the FORM - First Order Reliability Method with HLRF algorithm, implemented in Matlab environment, for the theoretical building CAARC. Large discrepancies between the failure probabilities of the two modes considered were found. For maximum acceleration, the design point value and the failure probability found were practical results. However, the horizontal displacement of 3 centimeters resulted in an extremely high probability of failure for low wind speed values, concluding that, for the tall building of the problem, the code limit tends to be easily extrapolated. Hence, the horizontal displacement parameter based on the total height of the building was also studied. Such analysis resulted in a failure probability greater than the acceleration one, however, presenting consistent design point values.

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Faber, Theodore V. "Dynamic time windows congestion control and avoidance in high speed networks /." 1994. http://catalog.hathitrust.org/api/volumes/oclc/32258126.html.

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Thesis (Ph. D.)--University of Wisconsin--Madison, 1994.
Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 193-204).

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YI-JHENG, LI, and 李義政. "Design and Implementation of Induction Motor Speed Control Systems in Windows CE.NET Environment." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/76725463495040341986.

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碩士
國立臺灣科技大學
電機工程系
93
An induction motor speed control system in Windows CE.NET environment is developed in this paper. First, decoupling of the motor torque and rotor flux amplitude is based on the indirect vector control method. Then, PI controller, sliding mode controller, fuzzy controller, and repetitive controller are designed to control the speed of the induction motor. Finally, on the base of PC control structure, we use EVC( Embed- ded Visual C/C++) and PB(Platform Builder) tool that Microsoft provided to develop driver and control program on Windows CE.NET operation system . Experimental results show that PI controller is designed easily, but it is sensitive to disturbance, which produce the steady-state error. Sliding mode control can strengthen the steady-sate condition, but it is sensitive to the disturbance, which produce the dither. Fuzzy control is basically an adaptive and nonlinear control, which is insensitive to the disturbance, and the settling time of fuzzy controller is shorter than that of PI controller and sliding mode controller. Repetitive controller can track periodic reference commands and attenuate periodic disturbances of the control system. The combinations of repetitive controller and PI controller can improve the stability of PI controller. The combinations of repetitive controller and sliding mode controller can reduce the periodic disturbance, and decrease the dither. The combinations of repetitive controller and fuzzy controller can improve the capability of periodic disturbance rejection.

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Tsegaye, M. A. "A comparative study of the Linux and windows device driver architecture with a focus on IEEE1394 (high speed serial bus) drivers." Thesis, 2004. http://eprints.ru.ac.za/55/1/Tsegaye-MSc.pdf.

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New hardware devices are continually being released to the public by hardware manufactures around the world. For these new devices to be usable under a PC operating system, device drivers that extend the functionality of the target operating system have to be constructed. This work examines and compares the device driver architectures currently in use by two of the most widely used operating systems, Microsoft’s Windows and Linux. The IEEE1394 (high speed serial bus) device driver stacks on each operating system are examined and compared as an example of a major device driver stack implementation, including driver requirements for the upcoming IEEE1394.1 bridging standard.

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Tsegaye, Melekam Asrat. "A comparative study of the Linux and windows device driver architecture with a focus on IEEE1394 (high speed serial bus) drivers /." 2002. http://eprints.ru.ac.za/55/.

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Yao-Min, Chen, and 陳耀民. "High Speed Data Stream Mining in the Weighted Sliding Window Model." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/13284978836754251609.

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碩士
明新科技大學
資訊管理研究所
95
In recent years, data stream mining has become an important research topic. With the emergence of new applications, the data we need to process is not again static, but the continuous dynamic data stream. Examples include network traffic analysis, Web click stream mining, network intrusion detection, and on-line transaction analysis. In this thesis, we propose a new structure for data stream mining, called the weighted sliding window model. Existent models such as the landmark model and the tilted-time window model consider the data generated from the starting time up to the current moment. However the weighted sliding window model can let the user specify the number of windows, the size of a window, and the weight for each window. The approach of allowing users to specify a higher weight to more significant data will make the mining result closer to the user’s requirement. We design a one-pass algorithm based on the weighted sliding window model, using a limited memory space, to efficiently discover all the large itemsets from data streams. Moreover, a new mechanism is proposed to improve the one-pass algorithm, which discovers all the large itemsets more efficiently.

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Silva, Francisco Jorge Carneiro Moreira da. "Investigation of the Process Window for Laser Surface Hardening a SAEM2 High-speed steel." Master's thesis, 2020. https://hdl.handle.net/10216/129642.

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Silva, Francisco Jorge Carneiro Moreira da. "Investigation of the Process Window for Laser Surface Hardening a SAEM2 High-speed steel." Dissertação, 2020. https://hdl.handle.net/10216/129642.

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Yhi, Chen San, and 陳尚逸. "The Sustainable-Cell-Rate Usage Parameter Control with Adjustable Window for High-Speed Multimedia Communications." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/62499126004479746444.

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碩士
國立交通大學
電信工程系
88
In this thesis, we first introduce the fuzzy TS-UPC model, which is conjunctions of the TS (traffic shaper) and the UPC (usage parameter controller) for sustainable-cell-rate usage parameter control in high-speed multimediacommunications. The fuzzy TS-UPC is composed of the fuzzy leaky bucket. The fuzzy increment controller (FIC), which is incorporated with the conventional leaky bucket algorithm in fuzzy leaky algorithm, properly choose the long-term mean rate and the short-term mean rate as input variables and intelligently compute to determine the increment value. Then we propose a enhanced fuzzy TS-UPC to improve the fuzzy TS-UPC. The enhanced fuzzy TS-UPC contains the FIC and a fuzzy window estimator (FWE). The FWE chooses the long-term mean rate and the short-term mean rate (in the updated short-term window) as input variables to decide the increment or decrease degree of the next short-term window. It helps to suitably adjust the short-term window for short-term mean rate calculations and then makthe short-term mean rate more correctly reflect the traffic conditions than the fixed short-term time window. Three performance measures such as selectivity, responsiveness, and queueing delay are considered. Simulation results show that the enhanced fuzzy TS-UPC can have better performance than the fuzzy TS-UPC. And the fuzzy TS-UPC outperforms the conventional TS-UPC. Next we propose the enhanced neural fuzzy TS-UPC, which is composed of the neural fuzzy increment control (NFIC) and the fuzzy window estimator (FWE) to make the TS-UPC more robust. The NFIC chooses the long-term mean rate and the short-term mean rate as input variables and then decide a more appropriate increment value. In the NFIC, the reinforcement learning can learn on line from a reinforcement signal (the difference between desired loss ratio and measured loss ratio), so the increment value can reflect the traffic conditions. The FWE described above suitably adjusts the short-term window and then make the short-term mean rate more correctly. Simulation results show that the enhanced neural fuzzy TS-UPC achieves the best performance in selectivity, responsiveness, and queueing delay, than all other TS-UPCs.

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Green, David W. "Extraction of wind speed from high frequency ground wave radar oceanic backscatter /." 2005.

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Chih-Neng, Yang, and 楊熾能. "The Effects of Text Presentation Methods and Window Sizes on Reading Speed, Comprehension, Reading Efficiency and Satisfaction." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/83410882650391042615.

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碩士
輔仁大學
資訊管理學系
94
The main purpose of this study was to investigate the effects of text presentation methods (paging, scrolling, leading, and rapid serial visual presentation) and window sizes (5x6 and 10x12) on subjects’ reading speed, comprehension, reading efficiency, and interface satisfaction on a personal digital assistant. The moderating effects of reading attitude, improper reading habit and reading behavior were also examined in this study. This study was participated with 30 subjects using a 4x2 factional repeated-measurement design. The reading materials used in the experiment were carefully selected from reading comprehension tests and screened via four steps: firstly, to select suitable groups of articles and questions by the researcher; secondly, to choose articles with medium difficulty by using a readability formula; thirdly, 15 undergraduates in the College of Management at Fu-Jen Catholic University took a comprehension test without reading material to screen out those easily guessable articles with no need of reading the content; finally, 11 undergraduates took an intact reading comprehension test presented with reading material and test items, and articles with obvious difficultly was deleted from the pool. The questionnaire used in this study was consisted of four sections: satisfaction of interface, reading attitude, reading behavior and personal data. The experimental application was implemented by researcher. Repeated-measurement ANOVA was conducted to test the hypotheses. Main findings were presented as follows: (1) Both text presentation methods and window sizes significantly influenced on subjects’ reading speed. (2) Neither text presentation methods nor window sizes had significant effect on subjects’ reading comprehension. (3) Subjects’ reading efficiency was significantly influenced by text presentation methods and window sizes. (4) Text presentation methods significantly influenced on subjects’ interface satisfaction. (5) Reading behavior had no moderating effect on subjects’ reading speed, comprehension, reading efficiency and interface satisfaction. Reading attitude and window sizes had significant interaction effect on subjects’ interface satisfaction. Improper reading habit and text presentation methods also had significant interaction effect on subjects’ reading efficiency.

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Yeh, Feng-Chang, and 葉豐彰. "A High-Efficiency Digitally-Controlled Switching Converter with Tracking Speed Enhancement for Windowed ADC Usage." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/18033022108243215138.

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碩士
國立清華大學
電機工程學系
98
Voltage scaling is a technique for high energy-efficiency operation. However, the voltage scaling technique requires a adaptive power-supply regulator, which is difficult and complex to implement by analog control. Digitally controlled dc-dc converters inherently have the characteristics of flexibility, robust and programmable, but its efficiency may be lower because of power waste in mixed signal data conversion. This thesis demonstrates a complete design of a digitally controlled buck converter for dynamic voltage systems. The converter senses the voltage error by a windowed ADC which consumes less power than a conventional ADC. A nonlinear digital controller is proposed to improve the tracking performance. A power MOS width slicing technique further increase the power efficiency. This design is fabricated in a 0.18-um CMOS process. The chip area is 2.9mm^2. The switching frequency is 5 MHz. The measurement result shows the power efficiency can achieve 93% and the tracking behavior could be several times improved by the proposed nonlinear control.

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"Wind responsive development in dense urban environment." 2003. http://library.cuhk.edu.hk/record=b5891782.

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Wong Ho Man, William.
"Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 2002-2003, design report."
Chapter 1 --- Introduction --- p.P.02
Chapter 2 --- Project Vision --- p.P.03
Chapter 3 --- Project Objectives --- p.P.04
Chapter 4 --- Research Plan and Methodology --- p.P.05
Chapter 5 --- Developed Wind Phenomenons --- p.P.07
Chapter 6 --- Investigation Process and Findings --- p.P.17
Chapter 7 --- Design Development --- p.P.24
Chapter 8 --- Final Design --- p.P.33
Chapter 9 --- Conclusion --- p.P.41

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39

Culver, Aaron Magelius Riis. "Not all speeds are created equal: investigating the predictability of statistically downscaled historical land surface winds over central Canada." Thesis, 2012. http://hdl.handle.net/1828/3908.

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A statistical downscaling approach based on multiple linear-regression is used to investigate the predictability of land surface winds over the Canadian prairies and Ontario. This study's model downscales mid-tropospheric predictors (wind components and speed, temperature, and geopotential height) from reanalysis products to predict historical wind observations at thirty-one airport-based weather surface stations in Canada. The model's performance is assessed as a function of: season; geographic location; averaging timescale of the wind statistics; and wind regime, as defined by how variable the vector wind is relative to its mean amplitude. Despite large differences in predictability characteristics between sites, several systematic results are observed. Consistent with recent studies, a strong anisotropy of predictability for vector quantities is observed, while some components are generally well predicted, others have no predictability. The predictability of mean quantities is greater on shorter averaging timescales. In general, the predictability of the surface wind speeds over the Canadian prairies and Ontario is poor; as is the predictability of sub-averaging timescale variability. These results and the relative predictability of vector and scalar wind quantities are interpreted with theoretically- and empirically-derived wind speed sensitivities to the resolved and unresolved variability in the vector winds. At most sites, and on longer averaging timescales, the scalar wind quantities are found to be highly sensitive to unresolved variability in the vector winds. These results demonstrate limitations to the statistical downscaling of wind speed and suggest that deterministic models which resolve the short-timescale variability may be necessary for successful predictions.
Graduate

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40

HUI, HUANG CHUNG, and 黃仲徽. "To Study The Affect of Heat-Release-Ratio under The Opening Ratio in Window and The Speed of Wind by FDS." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/91195226661271562492.

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碩士
高苑科技大學
機械與自動化工程研究所
104
In general, fire disaster is one of the extremely destructive disasters in this world.Generally, the opening ratio in window and the speed of wind are very important factors for affecting the fire. In this paper, the field simulation of the room fire has been carried on. The affect of HRR (Heat-Release-Ratio) by these factors was explored in FDS (Fire Dynamics Simulator) simulated software. Demonstrably, the results showed both of the opening ratio in window and the speed of wind are very important parameters in the fire.

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Davidson, James D. (James Douglas). "Methods for short-term prediction of wind speeds in the Pacific Northwest Columbia Gorge wind farm region." Thesis, 2012. http://hdl.handle.net/1957/30474.

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Variable electrical generation (VG) sources such as wind farms are an increasing percentage of total electrical generation in the Bonneville Power Administration (BPA) balancing area and are starting to impact the ability of the regional balancing authority to control the electric grid. Wind farms are not dispatchable and challenge historical electric grid control methods. Successful integration of VG at high penetration levels of wind needs to address increased overall system variability and the rapid power ramp rates caused by wind. One of the new control paradigms needed is accurate wind speed prediction which directly relates to wind farm power output. With an accurate wind speed forecast other generation sources can be dispatched as needed to ensure grid stability. This work uses BPA metrology station (MS) data to make predictions for short-term wind speed where short-term is defined as a one hour prediction horizon. It is shown that, using the available metrology station data and several different prediction methodologies, only small improvements in short-term wind speed prediction can be achieved with the available data for the algorithms analyzed.
Graduation date: 2013

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42

Scheffler, Christian. "Electromagnetic Pulse Welding Process and Material Parameter Identification for High Speed Processes." 2020. https://monarch.qucosa.de/id/qucosa%3A75198.

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Electromagnetic welding is an innovative, high-speed technology to manufacture mixed material joints. In this dissertation, an experimental-numerical method is presented to identify robust process windows of aluminum-copper and aluminum-steel compounds. The microstructural characteristics of these joints were investigated in detail. Moreover, an evaluation of the joint quality is presented and different numerical models were introduced for the simulation of macroscopic and microscopic effects. To improve the accuracy of the simulations, the strain rate sensitivity of the materials must be considered. For this purpose a high-speed setup for the identification of relevant viscoplastic material parameters, comprising an inverse evaluation strategy, was developed.

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Henriques, Marco António Oliveira. "Soldadura Por Explosão Alumínio - Aço Inoxidável: Influência de Placas Intermédias na Soldabilidade." Master's thesis, 2019. http://hdl.handle.net/10316/93601.

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Dissertação de Mestrado Integrado em Engenharia Mecânica apresentada à Faculdade de Ciências e Tecnologia
O presente trabalho tem como objetivo o estudo da ligação, por soldadura, entre materiais dissimilares, nomeadamente entre uma liga de alumínio (EN 573-3 - EN AW 6082 T6) e um aço inoxidável (EN 10088-2 - X5CrNi 18-10), através do processo de soldadura por explosão. Mais especificamente foi estudada a influência da utilização das placas intermédias na soldabilidade das placas a unir.Para isso foram realizados procedimentos experimentais em dois corpos de prova, tendo como elemento variável entre as experiências a utilização de dois materiais diferentes como placa intermédia, nomeadamente o aço ao carbono (EN10130 - DC05) e o chumbo, placas intermédias estas com espessura de 1 mm. Os restantes parâmetros do processo, bem como os materiais de base das placas estacionária e voadora, ambos com espessura de 3 mm, mantiveram-se para os dois procedimentos experimentais.Por motivos desconhecidos, o explosivo apresentou um comportamento inesperado em ambos os procedimentos, o que influenciou os resultados. Para além disso, o corpo de prova com placa intermédia de chumbo não soldou.O resultado destas experiências foi submetido a diversos ensaios, nomeadamente análise microestrutural ao microscópio ótico, SEM (microscopia eletrónica de varrimento), análise química por EDS (espectrometria de dispersão de energia), medição de microdurezas e ensaio de tração-corte complementada com análise de deformações pelo sistema ARAMIS® da GOM. As observações foram documentadas, sendo apresentadas e discutidas neste documento.Observou-se a formação de compostos intermetálicos na ligação alumínio – aço carbono, cuja fragilidade potenciou a propagação de fissuras nessa interface.Foi também evidenciado um aumento da dureza global nos materiais por comparação ao seu estado pré-soldadura, sendo essa variação mais significativa no aço inoxidável.
The present work has as objective the study of the welding connection between dissimilar materials, namely between an aluminium alloy (EN 573-3 - EN AW 6082 T6) and a stainless steel (EN 10088-2 - X5CrNi 18-10), through the explosion welding process. More specifically, the influence of the use of interlayers on the weldability of the joining plates was studied.For this purpose, experimental procedures were performed in two specimens, having as variable element between the experiments the use of two different materials as intermediate plate, namely carbon steel (EN10130 - DC05) and lead, intermediate plates with a thickness of 1 mm. The remaining process parameters as well as the 3 mm thick of base materials used for flyer and base plates were maintained for both experimental procedures.Due to unknown reasons, the explosive had presented unexpected behaviour in the both procedures performed, which had influenced the results achieved. Beyond that, the test piece with lead interlayer did not become welded.The results of these experiments were subjected to various tests, including microstructural analysis under optical microscope, SEM (scanning electron microscopy), chemical analysis by EDS (energy dispersion spectrometry), microhardness measurement and tensile testing complemented by strain analysis by the ARAMIS® - GOM system. Observations have been documented, presented and discussed in this document.The formation of intermetallic compounds was observed in the aluminium - carbon steel bond, whose brittleness potentiated the crack propagation in this interface.It was also evidenced an increase of the global hardness in the materials compared to their pre-welding state, this variation being more significant in stainless steel.

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Wardill, P. (Paul). "Dynamics of the thermosphere over Mawson, Antarctica / by P. Wardill." 1988. http://hdl.handle.net/2440/18805.

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Bibliography: leaves 140-151
151, [2] leaves : ill ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Thesis (Ph.D.)--University of Adelaide, Mawson Institute, 1989

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Compton, Andrea Jean. "The correlation of sea surface temperatures, sea level pressure and vertical wind shear with ten tropical cyclones between 1981-2010." Thesis, 2013. http://hdl.handle.net/1805/3669.

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Vaezi, Masoud. "Modeling and control of hydraulic wind power transfer systems." Thesis, 2014. http://hdl.handle.net/1805/6172.

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Indiana University-Purdue University Indianapolis (IUPUI)
Hydraulic wind power transfer systems deliver the captured energy by the blades to the generators differently. In the conventional systems this task is carried out by a gearbox or an intermediate medium. New generation of wind power systems transfer the captured energy by means of high-pressure hydraulic fluids. A hydraulic pump is connected to the blades shaft at a high distance from the ground, in nacelle, to pressurize a hydraulic flow down to ground level equipment through hoses. Multiple wind turbines can also pressurize a flow sending to a single hose toward the generator. The pressurized flow carries a large amount of energy which will be transferred to the mechanical energy by a hydraulic motor. Finally, a generator is connected to the hydraulic motor to generate electrical power. This hydraulic system runs under two main disturbances, wind speed fluctuations and load variations. Intermittent nature of the wind applies a fluctuating torque on the hydraulic pump shaft. Also, variations of the consumed electrical power by the grid cause a considerable load disturbance on the system. This thesis studies the hydraulic wind power transfer systems. To get a better understanding, a mathematical model of the system is developed and studied utilizing the governing equations for every single hydraulic component in the system. The mathematical model embodies nonlinearities which are inherited from the hydraulic components such as check valves, proportional valves, pressure relief valves, etc. An experimental prototype of the hydraulic wind power transfer systems is designed and implemented to study the dynamic behavior and operation of the system. The provided nonlinear mathematical model is then validated by experimental result from the prototype. Moreover, this thesis develops a control system for the hydraulic wind power transfer systems. To maintain a fixed frequency electrical voltage by the system, the generator should remain at a constant rotational speed. The fluctuating wind speed from the upstream, and the load variations from the downstream apply considerable disturbances on the system. A controller is designed and implemented to regulate the flow in the proportional valve and as a consequence the generator maintains its constant speed compensating for load and wind turbine disturbances. The control system is applied to the mathematical model as well as the experimental prototype by utilizing MATLAB/Simulink and dSPACE 1104 fast prototyping hardware and the results are compared.

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Бідник, Вікторія Сергіївна. "Вплив кліматичних факторів на запаси фітомаси в заказнику «Федотова коса» та Азово- Сиваському національному природному парку." Магістерська робота, 2020. https://dspace.znu.edu.ua/jspui/handle/12345/2986.

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Бідник В. С. Вплив кліматичних факторів на запаси фітомаси в заказнику «Федотова коса» та Азово- Сиваському національному природному парку : кваліфікаційна робота магістра спеціальності 091 "Біологія" / наук. керівник А. Г. Тунік. Запоріжжя : ЗНУ, 2020 81 с.
UA : Робота викладена на 81 сторінці друкованого тексту, містить 16 рисунків, 4 таблиць. Перелік посилань включає 47 джерел. Об’єктом дослідження стала трав’яниста рослинність заказника «Федотова коса» та Азово-Сиваського національного природного парку. Метою роботи було визначення впливу кліматичних умов на трав’янисту рослинність територій Азово-Сиваського національного природного парку та заказника «Федотова коса» за 2015-2019 роки. Методи дослідження – польовий експеримент, лабораторний аналіз, статистичний аналіз. У результаті експерименту визначено, що найбільше на запаси трав’янистої рослинності впливала швидкість вітру, менший вплив мали кількість опадів та температура повітря. Отримані підсумки дослідження можуть бути використані у літописі природи Азово-Сиваського національного природного парку та для подальших досліджень впливу клімату та диких копитних на трав’янисту рослинність. Новизна роботи полягає в тому, що , що вперше вивчається залежність трав’янистої рослинності Азово-Сиваського національного природного парку та заказника «Федотова коса» від кліматичних умов для біотопів луг та степ з відстежуванням сезонних змін
EN : The work is set out on 81 pages of printed text, contains 16 figures, 4 tables. The list of links includes 47 sources. The subject of the study was the herbaceous vegetation of the Azov-Sivash National Nature Park and the Fedotova Kosa The purpose of the work was to determine the influence of climatic conditions on the grassy vegetation of the territories of the Azov-Sivash National Nature Park and the Fedotova Kosa Nature Reserve for 2015-2019. Research methods – field experiment, laboratory analysis, statistical analysis. The experiment found that grassland vegetation was most influenced by wind speed, less rainfall, and air temperature. The results of the study can be used in the chronicle of the nature of the Azov-Sivash National Nature Park and for further studies of the effects of climate and wild ungulates on grassy vegetation. The novelty of the work is that, for the first time, the dependence of the herbaceous vegetation of the Azov-Sivash National Nature Park and the Fedotov Kos reserve on climatic conditions for meadows and steppes with seasonal changes is studied

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Dissertations / Theses on the topic 'Windows speed'

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