Dissertations / Theses on the topic 'EMF'
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1
Gatla, Goutham. "Validation of ModelicaML models." Thesis, Linköpings universitet, Programvara och system, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-86364.
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In the world of modeling, Model Validation plays a crucial role. A model editor is not said to becomplete without Validation. ModelicaML is a Modeling Language extended from a subset of UMLand SysML, developed under OpenModelica Project. It is defined to provide time-discrete andtime-continuous models. Papyrus Model Editor is extended to support for ModelicaML usingModelicaML Eclipse plug-in. This plug-in comes with Modelica Code Generator.Previously, ModelicaML plug-in had a prototype of validation which provided only Batch-modevalidation. The validation is used to be done by the Modelica compiler after the code generation phase.Each time the user tried to validate the model; first Modelica code is generated and then validated. Thistype of validation misses certain validation rules to validate due to the conversion from theModelicaML model to Modelica code.The goal of this thesis is to implement Model Validation done at model editor level with both Batch andLive mode validation. This can be done by developing an Eclipse plug-in which does the ModelValidation. This plug-in uses the EMF Validation framework for implementing the constraints andvalidation on ModelicaML models.
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Schuderer, Jürgen Rudolf. "EMF risk assessment: "in vitro" research and sleep studies /." Zürich, 2004. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=15347.
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Ohnuma, Takumi, Shinji Doki, and Shigeru Okuma. "Maximum torque control with inductance setting of extended EMF observer." IEEE, 2009. http://hdl.handle.net/2237/13950.
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Abdul, Malek Norun F. "3-D antenna array analysis using the induced EMF method." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13385.
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The effect of mutual coupling between elements plays a crucial role to the performance of the antenna arrays. The radiation patterns of antenna arrays will be altered by the coupling effect from the adjacent elements thus reducing the accuracy and resolution in direction finding application. This research developed and validated the novel 3-D Algorithm to calculate the far-field pattern of dipole arrays arranged in three dimensions and in any configuration (both in straight and slanted position). The effect of mutual coupling has been accounted using the Induced EMF method. The computation is performed on 2x2 parallel dipoles and 12 dipoles arranged at the edge of a cube. The results are validated with other electromagnetic techniques such as Method of Moment (MoM) and Finite Difference Time-Domain (FDTD). Then, a 2x2 dipole array is chosen for beam steering and experiment validation due to its ease of implementation and feeding network. The array optimisation to control the pattern is performed using a genetic algorithm. The far-field pattern computed using the 3-D algorithm might be less accurate than other 3-D electromagnetic techniques but its array optimisation is faster and efficient. The simulation and measurement results are in good agreement with each other confirmed the validity of the 3-D algorithm.
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Donovan, Alan. "On-line tool wear identification by tribo emf signal analysis." Thesis, Queensland University of Technology, 1993. https://eprints.qut.edu.au/107080/1/T%28BE%26E%29%20545%20On-line%20tool%20wear%20indentification%20by%20tribo%20emf%20signal%20analysis.pdf.
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The acoustic air-borne signal, the cutting tool vibration, and the stochastic component of the tribo emf signal produced by single point continuous turning operations have been analysed using statistical techniques. The correlation between variation in their statistical function values and the degree of cutting tool flank wear has been considered to determine to what extent they may be applied to "in-process" tool wear identification. The test program used a range of cutting parameters typical for the cutting of mild steel and high tensile cast iron using high speed steel and carbide
cutting tools. The acoustic sound and the tool vibration have been shown to have limited potential as a means of accurate tool wear identification. The tribo emf signal showed a greater dependence on the tool condition,
and accurate assessment was carried out using high tensile cast iron workpieces. The statistical variations of the tribo emf signal obtained for cutting mild steel were highlighted using pseudo random binary sequence slotted test workpieces. The method was developed, using a comparable sequence defined as a quasi random binary sequence, to investigate the response characteristics of the tribo emf by means of correlation analysis, and also to highlight the dynamic response of the lathe through spectral
analysis of vibration measured at the toolpost. A mathematical model of the contact conditions at the tool workpiece interface was proposed and tested; showing good correlation with monitored spectral variation of the
tribo emf for the cutting of cast iron.
Finally, conclusions have been made concerning the potential of the various stochastic signals for the purpose of in-process tool wear identification.
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Sereni, Elettra. "Study on cellular and molecular mechanisms underline the biological effects of extremely low frequency electromagnetic fields (ELF EMFs)." Doctoral thesis, Università di Siena, 2018. http://hdl.handle.net/11365/1046221.
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In the last decades, electromagnetic therapy generated an intense interest due to its use for the treatment of some pathological states related to musculoskeletal system. In particular, electromagnetic fields (EMFs) provide a therapeutic tool used to improve tissue regeneration in bone non-union fractures, to facilitate skin wound healing and to reduce pain symptomatology. This therapy represents a valid and non-invasive approach widely used to treat the area of interest avoiding side effects and the FDA approved its use to treat bone disorders. This therapy uses the electromagnetic radiations in the frequency range between 3 Hz and 300 Hz. These are non-ionizing and low energy radiations capable to induce heterogeneous effects on a very large number of biological processes such as cell cycle distribution and proliferation, apoptosis and cell migration. All of these effects vary in relation to frequency, amplitude, length of exposure and are also related to the intrinsic susceptibility of different cell lines. This aspect makes molecular investigations complicated because the cellular response is strictly related to the electromagnetic treatment used to irradiate samples. Since the mechanism of action by which this physical stimulus acts on cells is still lacking, our efforts have been addressed to define a coherent biochemical and molecular picture, considering the activities of the key enzymes of the most important metabolic pathways. Decreasing level in PKasic activity was found in cells exposed to ELF EMFs and this effect was associated with the inhibition of the isoform M2 of PK which is expressed in our cellular model. In literature, it has been described that this isoform is inhibited by a redox mechanism which cause the oxidation of the Cys358 residue, promoting a metabolic shift toward an anabolic state. Our biochemical results indicate that ELF EMFs treatments seem to elicit a similar response in NIH3T3 cells.
Moreover cell migration and proliferation, the two biological processes involved in wound healing process, has been studied using in vitro scratch assay in order to modeling the dynamic of the wound closure.
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Jermain, Robert F. "Effects of EMF Emissions from Undersea Electric Cables on Coral Reef Fishes." NSUWorks, 2016. http://nsuworks.nova.edu/occ_stuetd/418.
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The objective of this project was to determine if the electromagnetic field (EMF) emissions from undersea power cables impacted the local and transient marine life, with an emphasis on reef fishes. The work was done at South Florida Ocean Measurement Facility of Naval Surface Warfare Center, Carderock Division, Broward County, Florida. This facility functions as the hub for a range of active undersea detection and data transmission cables. It has multiple active submarine power cables that extend several miles offshore and which can deliver power and enable data transmission to and from a range of acoustic and EMF sensors. The cables lie directly on the seabed, are buried in the sand, or are suspended in the water column. EMF emissions from a selected cable were created during SCUBA fish surveys. During the surveys the transmission of either alternating current (AC) or Direct Current (DC) was randomly intiated by the facility with no transmitted current (OFF) provided a control. The surveys were conducted using standardized transect and stationary point count methods to acquire reef fish abundances prior to and immediately after a change in transmission frequency (the divers were aware of the time of frequency change but not the specific frequencies). The divers were also tasked to note the reaction of the reef fishes to the immediate change in the EMFs emitting from the cable during a power switch. The surveys were conducted on a quarterly basis at three sampling sites offshore on the same cable. These sites were in water depths of approximately 5, 10, and 15 m, respectively and were selected based on their robust reef fish community and are representative of each of the three primary hardbottom coral reef habitats in the local offshore environment: the Inner (Shallow), Middle, and Outer (Deep) reef tracts. A total of 263 surveys were conducted: 132 transect-counts and 131 point-counts over 15 months. There were 24,473 fishes counted during transect-count surveys and with point-counts, 36,115 fishes were counted. With count types and sites combine a total of 151 species representing 35 families were recorded. An analysis of the data primarily did not find statistical differences among power states and any variables. However, this may be a Type II error as there are strong indications of a potential difference of a higher abundance of reef fishes at the sites when the power was off. There are a number of caveats to consider with this finding: the data set needs to be larger in terms of numbers of: counts, sites and eletro-sensitive species to allow for rigorous statistical analysis; also a longer time between frequency changes to allow for slower, but nonetheless important, reactions to differing EMFs might lead to differing conclusions. Obviously, more research is required to confirm the results of this study.
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Stiller, Emilie [Verfasser]. "Vergleichende Untersuchung zur Bruchfestigkeit von voll- und teilgepressten EMF-Kronen / Emilie Stiller." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2013. http://d-nb.info/1031097260/34.
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Shao, Jianwen. "Direct Back EMF Detection Method for Sensorless Brushless DC (BLDC) Motor Drives." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/35065.
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Brushlesss dc (BLDC) motors and their drives are penetrating the market of home appliances, HVAC industry, and automotive applications in recent years because of their high efficiency, silent operation, compact form, reliability, and low maintenance.
Traditionally, BLDC motors are commutated in six-step pattern with commutation controlled by position sensors. To reduce cost and complexity of the drive system, sensorless drive is preferred. The existing sensorless control scheme with the conventional back EMF sensing based on motor neutral voltage for BLDC has certain drawbacks, which limit its applications.
In this thesis, a novel back EMF sensing scheme, direct back EMF detection, for sensorless BLDC drives is presented. For this scheme, the motor neutral voltage is not needed to measure the back EMFs. The true back EMF of the floating motor winding can be detected during off time of PWM because the terminal voltage of the motor is directly proportional to the phase back EMF during this interval. Also, the back EMF voltage is referenced to ground without any common mode noise. Therefore, this back EMF sensing method is immune to switching noise and common mode voltage. As a result, there are no attenuation and filtering necessary for the back EMFs sensing. This unique back EMF sensing method has superior performance to existing methods which rely on neutral voltage information, providing much wider motor speed range at low cost.
Based on the fundamental concept of the direct Back EMF detection, improved circuitry for low speed /low voltage and high voltage applications are also proposed in the thesis, which will further expand the applications of the sensorless BLDC motor drives.
Starting the motor is critical and sometime difficult for a BLDC sensorless system. A practical start-up tuning procedure for the sensorless system with the help of a dc tachometer is described in the thesis. This procedure has the maximum acceleration performance during the start-up and can be used for all different type applications.
An advanced mixed-signal microcontroller is developed so that the EMF sensing scheme is embedded in this low cost 8-bit microcontroller. This device is truly SOC (system-on-chip) product, with high-throughput Micro core, precision-analog circuit, in-system programmable memory and motor control peripherals integrated on a single die. A microcontroller-based sensorless BLDC drive system has been developed as well, which is suitable for various applications, including hard disk drive, fans, pumps, blowers, and home appliances, etc.Master of Science
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Ozturk, Salih Baris. "Direct torque control of permanent magnet synchronous motors with non-sinusoidal back-EMF." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2728.
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Schallmayer, Olivia [Verfasser]. "Einfluss von Vorwärm- und Gießtemperaturen auf das Ausfließverhalten von EMF - Legierungen / Olivia Schallmayer." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2013. http://d-nb.info/103289914X/34.
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Styrov, V. V., S. V. Simchenko, and V. N. Golotyuk. "Chemo-emf in the silicon solar cell exposed to low-energy hydrogen atoms." Thesis, Sumy State University, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20602.
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A new reactive gas-semiconductor system is experimentally found and examined
for the electron-hole pairs (e-h pairs) generation in the semiconductor due to exoergicty
of a surface chemical reaction. This system is “atomic hydrogen-crystalline silicon”. The
p-n silicon homojunction was used to produce chemo-emf and chemicurrent in the semi-
conductor system due to e-h pairs creation. The ideal geometry of the semiconductor
system would require the top semiconductor layer be of a nanosized thickness since only
the upper layer of the semiconductor is involved in chemical excitation. To make the
beginning of a research we howere harnessed the commercial silicon solar cell fabricat-
ed with the certain technological changes to have a bare semiconductor surface. A spe-
cial procedure was worked out to prepare the silicon surface free of the blocking layer of
silicon oxide.
The chemo-emf in the open circuit up to a few mV and the short circuit chemicur-
rent up to the record 700 nA were achieved that are the promising magnitudes to pave a
way for direct chemical energy to electrical energy conversion by semiconductor sys-
tems.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/20602
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Taha, Hilal. "ENABLING THE EXCHANGE OF METAMODELS DEFINED IN ECORE FROM JETBRAINS MPS TO EMF." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55495.
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Model-Driven Engineering has been developing since the first release of the Unified Modeling Language, passing several milestones and advancing ever since. Model-Driven Engineering is being used in various fields like medical, cyber-physical systems, web applications, etc. It is an engineering paradigm that allows developers to model systems at the level of abstraction of their choice. There are many available tools in the market offering different modelling capabilities to their users. Making use of more than one tool would give the users a wider range of options and higher flexibility in modelling their applications. The current market of open-source modelling tools has two main actors, being JetBrains MPS, mostly focused on textual modelling languages, and Eclipse Modelling Framework, mostly focused on graphical modelling languages. The goal of this thesis is to design and implement a bridge between these two modelling environments. More specifically, we engineer the modelling language Ecore, at the heart of the Eclipse Modeling Framework, in JetBrains MPS in order to enable the exchange of metamodels based on Ecore from MPS to Eclipse Modeling Framework.
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Lech, James Chrystopher. "Constructing an EMF radiation Hygeia framework and model to demonstrate a public interest override." Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/58695.
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Scientific views on EMF radiation dosimetry and models increasingly suggest that even a tiny increase in the incidence of diseases resulting from exposure to EMF radiation could have broad¹ implications for public health, social accounting and the economy. In South Africa (SA) there is no national EMF radiation exposure protection standard, statutory monitoring or regulations. Multinational High Court deliberations indicate the need for public interest EMF radiation exposure protection standards in South Africa. Domestic citizens, academics, as well as regulatory and legislative practitioners, are unable to effectively monitor and investigate EMF radiation exposure emissions from infrastructure sources, because industries refuse to provide the required data. Industries have, since 2003, continually obstructed access to the data and the establishment of a national EMF radiation standard, citing that it would be in conflict with their strategic economic interests. The demonstration of a public interest override (PIO) function is legislatively required to gain access to the required data. This study constructed (1) a framework and (2) a model to perform test simulations against the (3) PIO criteria to demonstrate a PIO function and tested one PIO simulation scenario. Testing the PIO scenario firstly required the construction of a public interest framework, drawing input from multiple disciplines. The framework literature review used systematic case law and scientific-technical analysis whilst the framework science sought to understand the connections, feedbacks, and trajectories that occur as a result of natural and human system processes and exchanges. The EMF radiation exposure system functions to support human wellbeing needs and to explore the benefits and losses associated with alternative futures with the goal to uncover the current and future limits thereof. In the second instance a HYGEIA² model was selected as a base investigation and forecast simulation tool. The study had to uncover the key attributes and parameters necessary to construct and to run successful EMF radiation exposure simulations. Thereafter the HYGEIA model was modified to specifically identify and evaluate EMF radiation exposure hazard conditions. Through subsequent simulation runs, the constructed framework was then tested. Requested anthroposphere information was synthesized within a systems model to forecast ecosystem services and human-use dynamics under alternative scenarios. The simulation used the model, the model references and the framework for guidelines, thus allowing multiple simulation / demonstration runs for different contexts or scenarios. The third step was the construction of a PIO checklist which guides criteria testing and provides a means of gaining pertinent information for further studies, based on this dissertation. Framework EMF radiation policy inputs into the model were intersected with identified vulnerable area facilities which were selected based on international criteria. The research output revealed potential EMF radiation violations which served as system feedback inputs in support of a demonstrated PIO function. The research recommends that the identified EMF radiation exposure violations of public health undergo a Promotion of Access to Information Act (PAIA) judicial review process to confirm the research findings. The judicial qualification of a PAIA PIO function of ‘substances released into the environment’ and ‘public safety or environmental risk’ would enable access to EMF radiation emissions data essential to future studies.
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Okuma, Shigeru, Shinji Doki, and Takumi Ohnuma. "Extended EMF Observer for Wide Speed Range Sensorless Control of Salient-pole Synchronous Motor Drives." IEEE, 2010. http://hdl.handle.net/2237/14475.
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Bhuiyan, E. H. "Monitoring movement in MRI by measuring changes in the EMF induced in head-mounted coils." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/44443/.
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Image quality is degraded by involuntary movement of the subject in an MRI scanner. It is fairly challenging in MRI of the brain to monitor the involuntary head movement accurately. Though there are a few techniques to monitor head movement of the subject for prospective motion correction, it is still an unsolved problem in MRI. In this study, head movement inside an MR scanner is monitored via measurement of changes in the voltage induced in head mounted coils by switched magnetic field gradients. The motion of a rigid body such as the human head is decomposed into two components: namely translation and rotation. There are three degrees of freedom (DOFs) for translational motion i.e. translation along the x, y and z axes and three rotational degrees of freedom for rotational motion i.e. rotation about the x, y and z axes. Head movement is monitored in a gradient field by measuring the change in induced voltage in head mounted coils. To calculate the change in induced voltage I follow two approaches: circular loops simulation, analytical as well as numerical calculations. I show that by using a standard method one can form a linear model to identify the position and orientation of the coils. An experimental arrangement is set up to check the validity of the analytical and numerical calculations. Experiments carried out with a rig of five coils verified that the changes in induced voltage in the coils is linear with respect to the changes in position of the coils. The linear model is also verified by comparing estimated positions obtained by using the coils to those found by image realignment of fast field echo (FFE) images using Statistical Parametric Mapping (SPM). We experimentally evaluate the new approach for monitoring head movement inside an MR scanner, which exploits the linear variation of the voltages induced in a set of coils by time-varying magnetic field gradients with respect to small changes in position/orientation. This approach was tested by attaching five coils to a structured agar phantom and a healthy volunteer's head. The results suggest that it is possible to estimate the position and orientation with 0.22 mm and 0.24˚ root-mean-square error using this set-up. The new approach could be used for prospective or retrospective motion correction. An experiment is also carried out by using free running EPI (Echo Planar Imaging) to track the head movement inside an MR scanner. There is a strong relation between head movement and EPI waveforms, the central point of the experiment is to track the head displacements via measuring induced voltage in the coils by using EPI waveforms during execution of free running EPI. The results obtained from the experiment reveal that the method is promising.
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Jomaa, Kassem. "Caractérisation du champ proche électromagnétique et exposition professionnelle aux ondes RF en milieu industriel." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT111/document.
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L'étude des émissions rayonnées d'une source dans tout l'espace, est essentielle pour l'analyse dosimétriques et l’analyse des interférences électromagnétiques. L'importance du dernier augmentent en raison de la nécessité d'avoir une prédiction de la fiabilité des circuits électroniques. De plus, l'utilisation quotidienne des dispositifs et des systèmes émettant des champs électromagnétiques radiofréquences ne cesse d'augmenter. Certains de ces dispositifs fonctionnent à proximité du corps humain, et les opérateurs se trouvent dans la région des champs proches de la source rayonnante, et ils sont exposés à des niveaux de champs électromagnétiques pouvant être élevés. Pour cette raison, l'analyse dosimétrique, qui passe par une cartographie tridimensionnelle (3D) au voisinage de la source rayonnante, doit être effectuée. Pour ce type d'applications, plusieurs scans des champs proches doivent être effectués dans différents plans afin de construire la cartographie de champs 3D. Étant un processus difficile dans les études de compatibilité électromagnétique, la caractérisation en champ proche est traitée par plusieurs algorithmes qui proposent différentes approches pour réaliser le scanning requis au voisinage de la source rayonnante.Dans ce travail, nous introduisons un système de scanning 3D avec des sondes de champ magnétique à trois axes à faible coût. Le fait de disposer de telles sondes permet la mesure simultanée des trois composantes du champ magnétique sur la base d'un seul scan au voisinage du dispositif testé. Les sondes conçues se composent de trois boucles orthogonales combinées ensemble; la première sonde contient trois boucles conventionnelles réunies dans un cube en plastique d'une dimension totale de 10 × 12 × 13 mm3, tandis que la deuxième sonde est une sonde PCB imprimée sur un substrat FR4 de 3,2 mm avec une dimension réduite de 9 × 9 × 3,2 mm3. Les sondes conçues ont été étalonnées avec une cellule TEM et les facteurs d'antenne correspondants ont été extraits. Le système de scanning présenté utilise comme un instrument de mesure un oscilloscope RF- 4 canaux, qui donne la possibilité de mesurer à la fois dans le domaine temporel et dans le domaine fréquentiel.La deuxième partie de cette thèse présente un algorithme de reconstruction basé sur la méthode du spectre d'ondes planes. Afin de réduire le nombre des scans et donc les exigences de temps, l'algorithme présenté nécessite juste un scan en champ proche 2D des composantes de champ, pour reconstruire la distribution du champ magnétique 3D au-dessus du dispositif rayonnant.La troisième partie de la thèse est consacrée à l'analyse dosimétrique des champs électromagnétiques rayonnés à proximité des systèmes RFID et des machines de soudage RF. L'évaluation de l'exposition en champ proche des champs rayonnés des antennes de lecture RFID, fonctionnant à 13,56 MHz et utilisées dans les bibliothèques, a été réalisée. Les mesures du champ magnétique près de l'antenne ont été établies à l'aide des sondes conçues. Les résultats sont ensuite analysés et comparés aux réglementations des normes européennes et des lignes directrices de l'ICNIRP. En outre, l'exposition aux champs électromagnétiques RF des travailleurs à proximité de machines de soudage RF dans un environnement industriel est étudiée. Ces machines, fonctionnant à 27 MHz, émettent de forts rayonnements et l'exposition a eu lieu dans la région de champ proche. La distribution spatiale des champs électromagnétiques dans cette région est étudiée à la fois dans des simulations numériques et des mesures réellesThe analysis of radiated emissions from a source throughout the space, is very essential for both dosimetric and electromagnetic interference analysis. The concerns about the latter are growing because of the need to have prediction of the system reliability of the electronic circuits. Moreover the everyday use of devices and systems emitting radio frequency electromagnetic fields is continuously increasing. Some of these devices are operating in the vicinity of human body, and operators are in the near-field region of the radiating source, and they are exposed to electromagnetic fields. For this reason, dosimetric analysis, that shows the necessity of having three dimensional (3D) field mapping in the vicinity of the radiating source, should be performed. For this kind of applications, several scans of the near fields should be done within different planes in order to build the 3D field mapping. Being a challenging process in electromagnetic compatibility studies, near field characterization is being treated by several algorithms that propose different approaches to achieve the required scanning on the radiating source.In this work, we introduce a 3D scanning system with a low cost three axis magnetic field probes. Having such probes allow the simultaneous measure of the three components of the magnetic field based on a single planner scan above the device under test. The designed probes consist of three orthogonal loops combined together; the first probe contains three conventional loops joined in a plastic cube with a total dimension of 10×12×13 mm3, whereas the second probe is a PCB probe printed on an FR4 substrate of 3.2 mm with a reduced dimension of 9×9×3.2 mm3. The designed probes were calibrated with a TEM cell and the corresponding antenna factors were extracted. The presented scanning system uses an oscilloscope as a measuring instrument that gives the possibility of both time and frequency domain measurements. The second part of this thesis presents a reconstruction algorithm based on plane wave spectrum method. In order to reduce the number of scans and hence the time requirements, the presented algorithm requires just a 2D near field scan of the field components, to reconstruct the 3D magnetic field distribution above the radiating device.The third part of the thesis is devoted for the dosimetric analysis of the radiated electromagnetic fields near RFID systems and RF-welding machines. The near-field exposure assessment of the radiated fields from RFID reader antennas operating at 13.56 MHz and used in Libraries was performed. The measurements of the magnetic field near the antenna were established using the designed probes. The results are then analyzed and compared to the regulations in European Directives and ICNIRP Guidelines. Moreover, the exposure to RF electromagnetic fields of workers near RF-welding machines in industrial environment is studied. These machines, operating at 27 MHz, emit strong radiation and the exposure takes place in the near-field region. The spatial distribution of the electromagnetic fields in this region is studied in both numerical simulations and measurements
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Oliveira, Galeno Côrtes Martins de. "Caracterização microestrutural e mecânica da liga NiTi com EMF produzida em forno de indução a vácuo." Instituto Tecnológico de Aeronáutica, 2010. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1102.
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Este trabalho consistiu da caracterização das propriedades mecânicas, temperaturas de transformação martensítica e aspectos microestruturais da liga Ti 50,67(%at) Ni com efeito de memória de forma previamente produzida via fusão em forno de indução a vácuo denominada VIM 51. Foram analisados três formatos de materiais : tiras de NiTi de 0,82 mm de espessura, chapas de 1,7 mm de espessura e fios de 3,5 mm de diâmetro. Verificou-se que o processo de conformação mecânica da liga VIM 51 foi perfeitamente viável. Análises de MEV/EDS mostraram e semi quantificaram a presença dos precipitados TiC, Ti2Ni e Ti3Ni4. Os ensaios de calorimetria diferencial de varredura mostram que os picos de transformação martensítica surgem em função do tempo de envelhecimento e da temperatura a que a liga é submetida. Amostras solubilizadas e envelhecidas a 450oC por 30 e 150 minutos apresentam dois picos de transformação no resfriamento e dois picos no aquecimento. Isto é atribuído a precipitação de Ti3Ni4 que ocorre preferencialmente nos contornos de grão, provocando heterogeneidade de composição no material. Os ensaios de tração mostraram que amostras simplesmente laminadas apresentam uma curva característica de material convencional enquanto as amostras solubilizadas, solubilizadas e envelhecidas apresentam platô característico de materiais que apresentam o efeito de memória de forma.Verificou-se que amostras envelhecidas a 350C e 600C apresentam comportamentos próximos das amostras simplesmente solubilizadas com valores de tensões de escoamento altos. Já as envelhecidas entre 400 e 500C apresentam baixos valores de tensão de escoamento, possivelmente devido a precipitação de Ti3Ni4, que em média deixa a matriz empobrecida em níquel aumentando, consequentemente, a temperatura de transformação martensítica.
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Zemko, Zoltán. "Modelovací nástroj pro grafický návrh komponentových systémů." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2013. http://www.nusl.cz/ntk/nusl-236174.
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Component-based Software Engineering describes a complex information system as a set of components. The thesis seeks to highlight the benefits of this approach. Also defines terms such as standard software, component software, and others. It provides an introduction to the modeling techniques of component-based systems in UML. The second half of the document describes the structure of the Eclipse Modeling Project. The reader by these lines should obtain a theoretical overview of the development of modeling tools under Eclipse. The document includes design and implementation process description of the tool for modeling component-based systems which has been developed using the Eclipse Modeling Framework and Graphical Modeling Framework.
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Bojana, Dimić Surla. "Софтверски систем за каталогизацију по MARC 21 формату." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2009. http://dx.doi.org/10.2298/NS20091228DIMICSURLA.
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Извршено је моделирање и имплементација софтверског система за каталогизацију по MARC 21 формату. За реализацију система коришћен је обједињени процес за развој софтвера, развој заснован на моделу и развој заснован на софтверским компонентама. Моделирање је извршено у CASE алату235 MagicDraw верзија 16.0 који подржава UML 2.0. Имплементација је реализована коришћењем Eclipse plug-in технологије и програмског језика Јава.У софтверском алату Xtext специфицирана је граматика за опис модела МАRC 21 записа. На основу ове граматике генерисан је основни едитор и EMF модел. Основни едитор је проширен додатним спецификацијама над EMF моделом. То су следеће спецификације: ограничења на структуру и садржај библиографских записа коришћењем језика Check; темплејти за трансформацију записа у форму каталошког листића коришћењем језика Xpand; понуда предефинисаног скупа података за унос у језику Xtend. Извршено је проширење основног едитора додатним функционалностима система за каталогизацију: приказ података о библиографском формату, унос локацијских података, експорт и импорт записа, приказ каталошких листића и библиотечко окружење. Коришћењем RCP технологије генерисана је софтверска компонента за каталогизацију која се може користити у различитим библиотечким информационим системима.Izvršeno je modeliranje i implementacija softverskog sistema za katalogizaciju po MARC 21 formatu. Za realizaciju sistema korišćen je objedinjeni proces za razvoj softvera, razvoj zasnovan na modelu i razvoj zasnovan na softverskim komponentama. Modeliranje je izvršeno u CASE alatu235 MagicDraw verzija 16.0 koji podržava UML 2.0. Implementacija je realizovana korišćenjem Eclipse plug-in tehnologije i programskog jezika Java.U softverskom alatu Xtext specificirana je gramatika za opis modela MARC 21 zapisa. Na osnovu ove gramatike generisan je osnovni editor i EMF model. Osnovni editor je proširen dodatnim specifikacijama nad EMF modelom. To su sledeće specifikacije: ograničenja na strukturu i sadržaj bibliografskih zapisa korišćenjem jezika Check; templejti za transformaciju zapisa u formu kataloškog listića korišćenjem jezika Xpand; ponuda predefinisanog skupa podataka za unos u jeziku Xtend. Izvršeno je proširenje osnovnog editora dodatnim funkcionalnostima sistema za katalogizaciju: prikaz podataka o bibliografskom formatu, unos lokacijskih podataka, eksport i import zapisa, prikaz kataloških listića i bibliotečko okruženje. Korišćenjem RCP tehnologije generisana je softverska komponenta za katalogizaciju koja se može koristiti u različitim bibliotečkim informacionim sistemima.
Modelling and implementation of software system for MARC 21 cataloguing have been done. Unified software development process is used as well as model-driven software development and component-based software development. System modelling is done in CASE tool MagicDraw (version 16.0) which supports UML 2.0. System implementation is realised using Eclipse plug-in technology and Java programming languages. Software tool Xtext is used for specification of MARC 21 record grammar. On the basis of this grammar the basic editor and its EMF model have been generated. The basic editor is extended with additional specifications on generated EMF model. Those specifications are: constraints on structure and content of bibliographic record written in Check language; Xpand templates for transforming records into cataloguing cards; content assist extensions written in Xtend. Addition functionalities of cataloguing system are also added to basic editor, and those are: showing data about MARC 21 format, entering holdings data, export and import of records, showing cataloguing cards and librarian environment. At the end, RCP technology is used for generating software component for cataloguing that can be used in different library information systems.
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Tabarraee, Kamran. "Dynamic average-value modeling of the 120° VSI-commutated brushless dc motors with non-sinusoidal back EMF." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/35740.
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For large and small signal analysis of electromechanical systems with power electronic devices such as Brushless DC (BLDC) motor-inverter drives, average-value models (AVMs) are indisputable. Average-value models are typically orders of magnitude faster than the corresponding detailed models. This advantage makes AVMs ideal for representing motor-drive components in system level studies. Derivation of accurate dynamic average-value model of BLDC motor-drive system is generally challenging and requires careful averaging of the stator phase voltages and currents over a prototypical switching interval (SI) to find the corresponding average-value relationships for the state variables and the resulting electromagnetic torque.
The so-called 120° voltage source inverter (VSI) driven brushless dc (BLDC) motors are very common in many commercial and industrial applications. This thesis extends the previous work and presents a new and improved dynamic average-value model (AVM) for such BLDC motor-drive systems. The new model is explicit and uses a proper model of the permanent magnet synchronous machine with non-sinusoidal rotor flux. The model utilizes multiple reference frame theory to properly include the back EMF harmonics as well as commutation and conduction intervals into the averaged voltage and torque relationships. The commutation angle is readily obtained from the detailed simulation.
The proposed model is then demonstrated on two typical industrial BLDC motors with differently-shaped back EMF waveforms (i.e. trapezoidal and close to sinusoidal). The results of studies are compared with experimental measurements as well as previously established state-of-the-art models, whereas the new model is shown to provide appreciable improvement especially for machines with pronounced trapezoidal back EMF.
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Santos, Júlio César. "Estudo da viabilidade do uso de fios da liga NiTi com EMF como eletrodos em dispositivos eletropirotécnicos." Instituto Tecnológico de Aeronáutica, 2011. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1546.
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Este é um trabalho de desenvolvimento tecnológico estudando a possibilidade do uso de fios da liga NiTi com Efeito de Memória de Forma (EMF) (com recuperação de forma de até 8%) como eletrodos em dispositivos eletropirotécnicos (DE), para ignição de motores foguetes a propelente sólido permitindo uma estanqueidade superior a gases quando comparados aos dispositivos convencionais. Foram testadas três composições em forma de fios: VIM 41 superelástico, VIM 47 e EB 7 martensíticos, todos em relação à temperatura ambiente. Verificou-se a dificuldade de se trabalhar com o fio da liga VIM 41 visto ser este superelástico à temperatura ambiente havendo, portanto, a necessidade de refrigeração abaixo da temperatura MF para posterior alongamento, corte e inserção (vinculação) no conector ou DE. Com fio VIM 47, martensítico, verificou-se que as cargas geradas no aquecimento, para deformações longitudinais pré-fixadas de 4 %, 6 % e 8 %, foram, respectivamente, de 326 MPa, 256 MPa e 176 MPa, isto é, tanto maior quanto menor a pré-deformação inicial. A simulação do possível uso como eletrodo em DE foi feita com os fios da liga EB 7 vinculados em conectores de carbeto de tungstênio. As cargas para pré-deformação longitudinal e as cargas de recuperação de forma (após um descarregamento para uma carga mínima de 10 N) cresceram com o aumento da pré-deformação de 6 %, 8 %, 10% e 12 %. Os resultados de estanqueidade, com exceção da deformação longitudinal de 10 %, foram tanto melhores quanto maiores foram as pré-deformações ultrapassando os valores especificados pela norma MIL-STD-1576 e concordantes com as cargas de desvinculação. Os resultados obtidos neste trabalho indicam a possibilidade do uso de fios com efeito de memória de forma como eletrodo em dispositivos eletropirotécnicos.
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Collard, Jean-François. "Etude des effets d’un courant électrique pulsé de basses fréquences sur les kératinocytes humains." Doctoral thesis, Universite Libre de Bruxelles, 2016. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/224675.
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Ces dernières décennies, les populations, civiles en général et professionnelles en particulier, ont été soumises à une exposition croissante aux champs électriques (EF) et magnétiques (MF) d'extrêmement basses fréquences (ELF). Différentes réponses biologiques ont été observées sur différents types de cellules et de tissus exposés à des courants et des champs ELF. Ces études permettent une meilleure connaissance de notre environnement électromagnétique mais les mécanismes biologiques précis et les implications des fréquences ELF sur la santé restent peu connus. Il est nécessaire de développer des protocoles de recherche pour répondre à ces questions. La revue exhaustive de la littérature met clairement en avant :- le manque de connaissance des mécanismes cellulaires activés après stimulation ELF;- l'importance de leur étude pour toutes recherches liées à l'utilisation de la stimulation ELF;- l'efficacité des techniques omiques qui permettent l'identification de ces mécanismes cellulaires;- l'importance du choix des modèles expérimentaux utilisés afin de faciliter l'extrapolation des résultats chez l'homme.Pour répondre à ces observations, nous avons recherché les gènes et les mécanismes cellulaires impliqués lors de la stimulation ELF sur un modèle de culture d'explants de kératinocytes humains mis en culture sur support dermique dévitalisé et stimulé par un courant électrique pulsé. Nous pensons que la recherche sur un modèle humain in vitro permet d'obtenir des résultats plus intéressants pouvant être extrapolés plus facilement aux études épidémiologiques ou cliniques.Les résultats préliminaires obtenus sur ce modèle de culture par Hinsenkamp et al. aboutissent à la même conclusion que leurs études des effets des champs sur le tissu osseux. Ils ont observés à partir de différents modèles, une maturation plus rapide de la matrice cartilagineuse associée à une accélération de l'ossification des tissus embryonnaires. Les analyses microarrays ont été réalisées sur 288 explants d'épiderme provenant de 3 cultures cellulaires indépendantes utilisant l'épiderme de 3 sujets différents. La première analyse des résultats montre que, pour un certain nombre de sondes, la valeur du taux d'expression est différente lorsque l'on compare deux à deux les conditions d'échantillonnage. Cette observation est valable pour l'évolution naturelle au cours du temps des cultures témoins (J4T/J1T :296 sondes; J7T/J1T :702 sondes; J12T/J1T :1006 sondes) ou des cultures stimulées (J4S/J1T :941 sondes; J7S/J1T :625 sondes; J12S/J1T :946 sondes) ainsi que pour la comparaison d'un temps stimulé à son temps témoin (J4S/J4T :304 sondes; J7S/J7T :220 sondes; J12S/J12T :496 sondes).L'analyse de l'évolution des résultats au cours du temps (comparaison de Jx à J1) pour le groupe témoin et stimulé montre que, si la stimulation augmente ou diminue la régulation de certains gènes par rapport à J1 (témoin), la variation n'est généralement pas suffisante pour statistiquement inverser le sens de la régulation naturellement observée dans le temps. Seuls 3 gènes (EPS8, ADAMTS1, NOS1) ne suivent pas cette règle.De plus, la comparaison des listes de gènes aux 3 temps d'échantillonnage J4, J7 et J12, montre que 3 gènes sont systématiquement exprimés dans les trois groupes stimulés comparés à leur témoin respectif :TXNRD1, ATF3 et MME. Ils sont connus pour jouer un rôle dans la prolifération, la différenciation et la mitose. L'analyse du rôle joué par DKK1 et MACF1 au temps J4 montre que la sur-expression de DKK1 et la sous-expression de MACF1 ont pour effet l'inhibition du "pathway Wnt" ce qui provoque une diminution de la prolifération et une augmentation de la différenciation terminale. Parmi les variations intéressantes, BMP-2 est sur-exprimée au temps J12. Cette protéine est connue pour jouer un rôle important dans l'ostéogenèse, l'angiogenèse et la maturation cellulaire.Une analyse par triangulation montre que la stimulation par un courant ELF pulsé accélère la sur- ou la sous-expression de certains gènes qui, dans des circonstances normales (groupe témoin non stimulé), auraient suivi la même tendance (sur- ou sous-régulation) mais de manière plus lente. Parmi ces gènes, CHEK1, DKK1, NDRG4, SPRR3 sont connus pour jouer un rôle dans la prolifération et la différenciation; UBE2D3 est actif dans la voie de signalisation de la BMP-2; les autres gènes sont actifs dans la mitose, le développement cellulaire et la réplication de l'ADN.Nous avons ensuite utilisé des outils informatiques qui permettent une analyse sans apriori des résultats :L'analyse du graphe orienté acyclique généré par WebGestalt sur base des données de GO a mis en évidence les processus biologiques impliquant les gènes présents dans nos résultats et dont la régulation a été modifiée. Ces gènes ont des fonctions dans les mécanismes du cycle cellulaire, de la mitose, de la prolifération ou de la différenciation. Ces résultats sont cohérents avec les résultats macroscopiques précédents et les premières observations présentées ci-dessus.Pour mettre en évidence les voies de signalisation actives dans les processus biologiques, nous avons utilisé KEGG qui indique que les voies "cycle cellulaire" et "voie de signalisation de p53" utilisent un nombre statistiquement significatif de gènes présents dans nos résultats. Le cycle cellulaire et la mitose sont impliqués dans la prolifération cellulaire. La différenciation a également besoin de cette étape proliférative puisque ce sont les cellules filles qui deviendront des cellules matures. La "voie de signalisation p53" est également active dans le cycle cellulaire, la différenciation, l'apoptose et le maintien de l'intégrité cellulaire. L'analyse des voies connexes à "p53" et à "cycle cellulaire", utilisant des gènes présents dans nos résultats, a mis en avant plusieurs cascades dont certaines utilisent des gènes actuellement connus pour n'avoir de rôle que dans une seule cascade. Ces gènes sont des candidats potentiels à la fonction de marqueur de la stimulation ELF. On y retrouve entre autre FoxO :régulé par JNK (membre des MAPK), actif avec TGF-β1 dans la migration cellulaire et la diminution de l'apoptose; Jak/STAT qui active la voie "cytokine-cytokine receptor interaction" utile lors de la prolifération, différenciation, migration, apoptose et survie cellulaire; Wnt qui régule la prolifération, la différenciation ainsi que la mobilité cellulaire. D'autres voies d'intérêt mais n'utilisant pas de gène ayant une fonction unique ont été listées :PI3K/Akt, en partie régulée par la phosphorylation de FoxO, a une fonction dans la prolifération cellulaire.Les différentes analyses réalisées avec Pathway studio confirment qu'une grande majorité des gènes présents dans nos résultats sont actifs dans les processus de prolifération, différenciation, croissance cellulaire, cycle cellulaire, mitose, apoptose, migration et survie cellulaire. Plusieurs gènes et mécanismes discutés précédemment (ADAMTS1, ATF3, BMP-2, DKK1, DUSP4, MACF1, MME, PDGFRA, SFRP1, TXNRD1, WNT) ont été isolés par le programme. La recherche des mécanismes utilisant les gènes isolés lors de l'analyse par triangulation les relie à la prolifération, la différenciation, l'adhésion cellulaire, la réplication de l'ADN et la mort cellulaire.Pathway Studio nous a permis de localiser dans la cellule les protéines qui devraient finalement être traduites suite à la modification de l'expression de leurs gènes. Cette analyse permet d'étudier les interactions entre l'extérieur et l'intérieur de la cellule ainsi que rechercher les protéines stimulant un grand nombre d'autres protéines ou recevant un grand nombre de stimuli. La protéine extracellulaire Endothelin 1 (ET-1), codée par le gène EDN1, agit sur 9 protéines membranaires différentes :EGFR par l'intermédiaire de la signalisation des MAPK; PDGFRA; GLUT-3 (exprimé à partir du gène SLC2A3); COX-2 (exprimée à partir du gène PTGS2); EP4 (exprimée à partir du gène PTGER4); PLAUR et les gènes IER3, CD44 et IL6ST qui seront traduits en protéines membranaires. Neuregulin 1, codée par le gène NRG1, est la seconde protéine extracellulaire la plus active vers les protéines membranaires différentes. L'analyse des résultats met en évidence 840 interactions entre une protéine extracellulaire et une protéine nucléaire en incluant une protéine membranaire et une protéine cytoplasmique. Les protéines membranaires recevant des informations du plus grand nombre de protéines extracellulaires sont EGFR et FAS. C'est également EGFR, une des voies de signalisation les plus importantes de la régulation de la croissance, la survie, la prolifération et la différenciation cellulaire, qui transmet le plus d'informations aux protéines cytoplasmiques. FAS est capable de réguler l'apoptose et la prolifération en fonction du taux de fixation de son ligand.A l'aide d'un screening par la technique des microarrays de l'expression des gènes réalisé sur des échantillons témoins et stimulés, nous avons :- vérifié la cohérence des résultats avec les études historiques;- mis en évidence les processus biologiques responsables de la réponse cellulaire observée;- isolé une liste de gènes "marqueurs potentiels" impliqués spécifiquement dans ces mécanismes:- vérifié l'hypothèse que la stimulation ELF accélère dans le temps l'apparition de phénomènes qui seraient apparus naturellement mais avec une latence plus longue.Les observations faites dans le cadre de cette étude ont mis en évidence un nombre important d'informations. Plusieurs d'entre elles nécessitent des recherches complémentaires afin de préciser et de confirmer les résultats. Il serait intéressant :- de comparer et de grouper les résultats de la littérature montrant des effets similaires même si la stimulation ou le modèle de culture sont différents;- de développer les techniques de microdosimétrie afin de connaître avec précision la stimulation reçue par la cellule;- de développer l'étude des signaux afin de découvrir la composante active qui déclenche la réaction de la cellule;- de mettre en place un protocole étudiant la voie métabolique Wnt sur des cellules sanguines en incluant un dosage de la β-caténine pour étudier l'effet de la stimulation sur la leucémie infantile. Il faudra vérifier que les gènes exprimés dans nos résultats soient finalement traduits en protéines actives afin de confirmer leur rôle comme marqueurs de la stimulation ELF.Doctorat en Sciences biomédicales et pharmaceutiques (Médecine)
info:eu-repo/semantics/nonPublished
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Sičkaruk, Roman. "Program pro export vektorových obrázků z Autodesk Eagle." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400898.
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This master’s thesis deals with design and creation of ULP program for export of vector images in EMF (Enhanced Windows Metafile) format. The main aim of this thesis is to add support of all features of Autodesk Eagle version 9. Thesis is important due to bugs and imperfections of other ULP programs for exporting of vector images to other formats also because of they aim for older versions of Autodesk Eagle. With regard to small quantity of EMF literature, thesis is beneficial as it describes behaviour of base structures and describes creation of EMF metafile. It also provides example of iteration over individual parts of schemes and printed circuit boards. Main goal of this thesis was completed. User is allowed to export currently visible layers, set order of their printing, with remain of true colors and orientation. Program was tested in Autodesk Eagle systems version 9.1.3 and 9.3.2.
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Pumpe, Marco [Verfasser]. "Einfluss der Dauer und der Temperatur von Oxidbränden auf die Verbundfestigkeit zwischen Keramik und EMF-Legierungen / Marco Pumpe." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2008. http://d-nb.info/1023260131/34.
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Andrade, Elaine Cristina. "Efeito do tratamento térmico no aço inoxidável Fe-Mn-Si-Cr-Ni-Co com EMF processado por trefilação." Instituto Tecnológico de Aeronáutica, 2013. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=2283.
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Neste trabalho é apresentado o efeito do tratamento térmico no aço inoxidável Fe-Mn-Si-Cr-Ni-Co com Efeito de Memória de Forma (EMF), processado por trefilação com diferentes reduções de áreas (RA). As amostras foram caracterizadas em termos da evolução microestrutural e do EMF. A caracterização microestrutural foi realizada com o auxílio de técnicas de microscopia óptica e microscopia eletrônica de varredura, e medidas obtidas por difração de raios X. Foram realizadas medidas de dureza Vickers para acompanhar o encruamento e o amolecimento das amostras tratadas termicamente. A caracterização do EMF foi realizada por meio de ensaios de tração, com deformação de até 4%. A técnica de trefilação com posterior tratamento térmico de recozimento promoveu aumento na dureza do aço inoxidável em estudo de até 639 25 HV para a condição deformada com 57% de RA, seguida de recozimento em 550C por 1 h. Obteve-se uma recuperação de forma total de até 83% para uma amostra deformada com 57% de RA, seguida de recozimento em 850C durante 1 h.
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Huber, Verena [Verfasser]. "Vergleichende klinische Nachuntersuchungen von zahn- und implantatgetragenen Brücken aus einer verblendeten edelmetallfreien Legierung (EMF) und Zirkoniumdioxid / Verena Huber." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2020. http://d-nb.info/1218076526/34.
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Pym, Bolleri Donatien. "Le statut juridique des établissements de microfinance (EMF) en zone CEMAC (Communauté Economique et Monétaire de l'Afrique Centrale)." Thesis, Paris 9, 2013. http://www.theses.fr/2013PA090074.
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L’édiction d’un statut juridique pour les établissements de micro-Finance (EMF) dans la Communauté Economique et Monétaire des Etats de l’Afrique Centrale (CEMAC) était une impérieuse nécessité ; car il fallait encadrer l’activité de micro-Finance et ses acteurs. Cette initiative s’est traduite dans le Règlement du 13 avril 2002 à travers une double mesure. D’une part, la sécurisation du secteur de la micro-Finance qui s’illustre par la régulation de l’accès à l’activité de micro-Finance et la règlementation de l’exercice de ladite activité. D’autre part, le législateur a procédé à la spécialisation des EMF, en leur assignant deux types de missions fondamentales, lesquelles les distinguent des établissements de crédit classiques. Il s’agit de la canalisation par les établissements de micro-Finance des exclus du système bancaire classique ; ainsi que du financement par ces établissements des initiatives économiques de base. Le statut juridique érigé par le législateur sous-Régional de la CEMAC est une importante avancée dans l’encadrement de l’activité de micro-Finance. Néanmoins, cette œuvre est perfectible. L’un des axes d’amélioration du statut ainsi élaboré consiste à procéder à une meilleure différenciation des diverses formes juridiques que peuvent revêtir les EMF. Ceux-Ci peuvent en effet avoir, soit des formes sociétaires (capitalistes ou mutualistes) ; soit des formes associatives caritatives ou lucratives. Cette variété de formes juridiques semble contredire l’unité statutaire mis en exergue par le législateur.L’autre axe de perfectionnement du statut des EMF est l’amélioration de leur régime juridique. Pour y arriver, il faut affiner le cadre institutionnel et opérationnel des EMF. Au plan institutionnel, il est judicieux de redéfinir le rôle des institutions intervenant dans le secteur de la micro-Finance, en consolidant leurs atouts. Au niveau opérationnel, la spécificité de l’activité de micro-Finance invite à mieux assimiler les contours des liens contractuels qui se tissent entre les différents acteurs du secteur de la micro-Finance. L’idéal étant de normaliser les sûretés originales et les voies d’exécution atypiques utilisées en micro-Finance.Pour atteindre l’objectif très louable de viabilité et de pérennité des EMF en tant qu’acteurs importants de l’économie, l’effectivité et l’efficacité de la règlementation doit être une réalitéThe enactment of a legal status for microfinance institutions (MFIs) in the Economic and Monetary Community of Central African States (CEMAC) was an urgent need for it ought to monitor the activities of microfinance and its actors. This initiative resulted in the Rules of April 13, 2002 through two ways. On the one hand, securing the microfinance sector which has led to the regulation of access to microfinance activity and regulation of the exercise of that activity. On the other hand, the legislator has made the specialization of MFIs, assigning two types of basic tasks, which distinguish them from traditional credit institutions. Microfinance institutions come to the rescue of those who are excluded from the classical banking sector and they equally finance petty economic activities.The legal status enacted by the sub-Regional legislator of CEMAC is an important advancement in the management of the business microfinance. Nevertheless, this work can be improved upon.One of the ways of improving the status and is prepared to make a better differentiation of various legal forms that microfinance institutions may take. They may indeed have, either company forms (capitalist or mutual), is charitable or profit associative forms. This variety of legal forms appears to contradict the statutory unit highlighted by the legislator.Another axis of development status of microfinance institutions is the improvement of their legal status. To get there, we must refine the institutional and operational framework for microfinance institutions. At the institutional level, it makes sense to redefine the role of institutions involved in the microfinance sector, consolidating their assets. At the operational level, the specificity of the activity of microfinance invited to better assimilate the contours of contractual relationships that develop between the various actors in the microfinance sector. The ideal is to normalize the original collateral and atypical of enforcement used in microfinance.To achieve the laudable goal of viability and sustainability of MFIs as important players in the economy, efficiency and effectiveness of the regulations must be a reality
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Sandström, Malin. "Structural and solid state EMF studies of phases in the CaO–K2O–P2O5 system with relevance for biomass combustion." Doctoral thesis, Umeå universitet, Tillämpad fysik och elektronik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-858.
Full textAbstract:
Fosfaters reaktioner i energiomvandlingsprocesser är kritisk för den generella processen som helhet, för askrelaterade problem, emissioner liksom för en effektiv och hållbar användning av askan. Denna avhandling är en sammanställning och diskussion med utgångspunkt i åtta artiklar som behandlar strukturella och termodynamiska studier på faser i CaO-K2O-P2O5-systemet, vilka är av relevans inom förbränning av biomassa. Målsättningen med denna avhandling var: i) att sammanställa och granska tillgängliga strukturella och termodynamiska data i CaO-K2O-P2O5-systemet samt att identifiera avsaknad av data, ii) att fylla i dessa luckor med grundläggande termodynamiska, strukturella och fasstabilitets studier samt iii) att visa på användning samt fördelarna med dessa nya data vid praktisk tillämpning. En initial litteraturundersökning i CaO-K2O-P2O5-systemet visade att det saknades både strukturella och termodynamiska data. När det gällde tillgängliga termodynamiska data var situationen särskilt otillfredsställande. Det fanns endast data för några kalcium– och kaliumfosfater med varierande tillförlitlighet. Situationen beträffande pulverröntgen för fasidentifiering var bättre, fast fördunklad av det faktum att strukturellt liknande fasövergångar ofta förekommer i det undersökta systemet. Däremot fattades det tillfredställande enkristallstrukturdata för ternära faser i det undersökta systemet. Enkristallröntgendiffraktion användes för att bestämma strukturerna för CaK2P2O7, CaKP3O9, Ca10K(PO4)7 och CaKPO4. Faserna CaK2P2O7 and CaKPO4 tillsammans med Ca3(PO4)2, KPO3 och K4P2O7 studerades med pulverröntgendiffraktion och termiska analysmetoder för att klargöra fasmodifikationer och övergångstemperaturer. Gibbs bildningsenergi bestämdes för Ca(PO3)2, Ca2P2O7, Ca3(PO4)2, Ca10K(PO4)7, CaK2P2O7, CaKPO4 och CaK4(PO4)2 med ems-metodik och yttriastabiliserad zirkonia som fast elektrolyt och Ni/Ni3P som hjälpsystem. Både de strukturella och termodynamiska data användes sedan vid analyser i ett förbrännningexperiment av olika sädesslag. Framtagna data användes både vid identifiering och även vid kvantifiering av bildade faser i biomassaresterna.The behaviour of phosphates in thermochemical biomass conversion processes are critical for the general process chemistry, for ash related problems, for emissions as well as for an efficient, sustainable and beneficial use of the ash residues. This thesis is a summary and a discussion of eight papers dealing with structural and thermodynamical studies of phases in the CaO-K2O-P2O5 system, with relevance for biomass combustion. The objectives were: i) to compile and review the available structural and thermodynamical data of phases in the CaO-K2O-P2O5 system as well as to identify existing gaps in the field of these data, ii) to fill in as many as possible of the gaps by fundamental thermodynamic, structural and phase stability studies and iii) to demonstrate the uses and the benefits of the new data in practical applications. An initial review of the CaO-K2O-P2O5 system showed that both structural information and thermodynamic data were lacking. The situation regarding the available thermodynamic data was especially unsatisfactory, data could only be found for some few calcium phosphates and a few potassium phosphates with varying reliability. Concerning powder X-ray diffraction patterns for phase identification the situation was better, though obscured by the fact that structurally close related phase transitions often occur in the studied system. However, adequate single crystal structural data of ternary phases in the system was completely missing. Crystal structures of CaK2P2O7, CaKP3O9, Ca10K(PO4)7 and CaKPO4 were determined by single-crystal X-ray diffraction. The phases CaK2P2O7 and CaKPO4 were together with Ca3(PO4)2, KPO3 and K4P2O7, investigated by powder X-ray diffraction and thermal analysis to elucidate phase modifications and transitions temperatures. Gibbs standard energy of formation was determined for Ca(PO3)2, Ca2P2O7, Ca3(PO4)2, Ca10K(PO4)7, CaK2P2O7, CaKPO4 and CaK4(PO4)2 by solid state emf measurements with yttria stabilised zirconia as solid electrolyte and Ni/Ni3P as auxiliary solid couple. Both the structural and thermodynamical data were subsequently utilised in analysis of a combustion experiment of cereal grains. The data were also used to both identify and quantify the phases formed in biomass combustion residues.
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Anguiano, Sanjurjo David. "Investigation of Hybrid Simulation Methods for Evaluation of EMF Exposure in Close Proximity of 5G Millimeter-Wave Base Stations." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284324.
Full textAbstract:
With the emergence of Fifth Generation (5G) mobile networks, the employment ofhigher frequencies in the millimeter-wave (mmWave) range and the realization of agreat number of beams in 5G radio base stations (RBS) make the electromagnetic (EM)simulation of RBS products very costly in terms of hardware and time requirements.In order to compute the electromagnetic field (EMF) exposure in close proximity of theRBS, more efficient simulation methods are required.The move to mmWave frequencies enables the use of the so-called high frequencymethods for EM simulation with RBS antennas. In this thesis, conventional fullwavesimulation solvers and different implementations of hybridization of highfrequency methods with conventional methods are used with different commercial EMsimulation tools, and their performance is evaluated for the purpose of EMF exposureassessment in close proximity of 5G mmWave RBS.Among all the investigated methods, the hybrid scheme with Finite IntegrationTechnique (FIT) and Shooting and Bouncing Rays (SBR) methods, e.g., thatimplemented in CST Studio Suite 2020, outperforms in terms of hardwarerequirements and time costs, although the accuracy is compromised on the side andbehind the mmWave RBS. The Multilevel Fast Multipole Method (MLFMM), e.g.,that implemented in Altair FEKO 2019, though not a hybrid method, also has goodperformance but requires very large Random Access Memory (RAM), and it cannothandle very exquisite details of RBS. The Finite Difference Time Domain (FDTD)method implemented in EMPIRE XPU can also handle the investigated problemseffciently, but for extremely large problems, its requirements on RAM may become thebottleneck. In the thesis, many other hybrid implementations are also investigated,but it is found that they are not suitable for the EMF exposure assessment in closeproximity of the mmWave RBS with evaluation on a planar area of 0.42 m × 1 m at 28 GHz due to various reasons.För den femte generationens (5G) mobilnät kommer användningen av millimetervågoroch det stora antalet lober som en radiobasstation (RBS) kan hantera att betydaett kraftigt ökat behov av hårdvara och större tidsåtgång för att göra beräkningarav exponeringen för elektromagnetiska fält nära utrustningen. Därför behövs mereffektiva simuleringsmetoder.Eftersom systemen opererar på millimetervåg-frekvenser kan högfrekvensmetoderanvändas i simuleringen av simuleringen av en RBS. I den här avhandlingenutvärderas konventionella metoder, samt olika hybridmetoder för beräkningenav EMF-exponeringen av millimetervågor i närheten av en RBS. De utvärderadehybridmetoderna är implementerade i olika mjukvaror och blandar användandet avhögfrekvensmetoder och konventionella metoder.Av alla utvärderade metoder fungerar hybridmetoden implementerad med finitaintegralmetoden (FIT) och ”Shooting and Bouncing Rays”-metoden (SBR) i CST bästi termer av vilken hårdvara som behövs för beräkningarna och för tidsåtgången.Dock är noggrannheten i beräkningarna på sidan av och bakom RBSen mindrebra. Multilevel Fast Multipole Method (MLFMM)”-lösaren i Feko i FEKO använderingen hybridmetod men presterar bra, men den kräver mycket RAM-minne och kaninte ta hänsyn till små detaljer i RBSen. Finita differensmetoden i tidsdomänen(FDTD) i EMPIRE kan också användas men dess RAM-krav blir en flaskhals förstora simuleringar. Ytterligare hybridmetoder är undersökta i avhandlingen men medslutsatsen att de inte är användbara (av olika anledningar) för beräkningen av EMFexponeringenfrån en RBS opererandes på frekvensen 28 GHz och över en yta som är0.42 x 1 m.
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Loughran, Sarah Patricia, and n/a. "The efffects of eletromagnetic fields emitted by mobile phones on human sleep and melatonin production." Swinburne University of Technology, 2007. http://adt.lib.swin.edu.au./public/adt-VSWT20070731.100218.
Full textAbstract:
The use of mobile phones is continually increasing throughout the world, with
recent figures showing that there are currently more than 2 billion mobile
phone users worldwide. However, despite the recognised benefits of the
introduction and widespread use of mobile phone technologies, concerns
regarding the potential health effects of exposure to the radiofrequency
electromagnetic fields emitted by mobile phone handsets have similarly
increased, leading to an increase in demand for scientific research to
investigate the possibility of health effects related to the use of mobile
phones.
An increasing amount of radiofrequency bioeffects research related to mobile
phone use has focussed on the possible effects of mobile phone exposure on
human brain activity and function, particularly as the absorption of energy in
the head and brain region is much higher than in other body regions, which is
a direct result from the close proximity of the mobile phone to the head when
in normal use. In particular, the use of sleep research has become a more
widely used technique for assessing the possible effects of mobile phones on
human health and wellbeing, and is particularly useful for providing important
information in the establishment of possible radiofrequency bioeffects,
especially in the investigation of potential changes in sleep architecture
resulting from mobile phone use.
A review of the previous literature showed that a number of studies have
reported an increase in the electroencephalogram spectral power within the 8
� 14 Hz frequency range in both awake and sleep states following
radiofrequency electromagnetic field exposure. In regards to sleep, the
enhancements reported have not been entirely consistent, with some early
studies failing to find an effect, while more recent studies have reported that
the effect differs in terms of particular frequency range. However, in general
the previous literature suggests that there is an effect of mobile phone
emissions on the sleep electroencephalogram, particularly in the frequency
range of sleep spindle activity.
In addition to changes in spectral power, changes in other conventional sleep
parameters and the production and secretion of melatonin have also been
investigated, however, there has been little or no consistency in the findings
of previous studies, with the majority of recent studies concluding that there
is no influence of mobile phone radiofrequency fields on these parameters of
sleep or melatonin.
Following a detailed review of the previous research, the current study was
developed with the aim to improve on previous methodological and statistical
limitations, whilst also being the largest study to investigate mobile phone
radiofrequency bioeffects on human sleep. The principle aims were thus to
test for the immediate effects of mobile phone radiofrequency
electromagnetic fields on human sleep architecture and the secretion of the
pineal hormone, melatonin.
The experiment included 50 participants who were randomly exposed to
active and sham mobile phone exposure conditions (one week apart) for 30
minutes prior to a full night-time sleep episode. The experimental nights
employed a randomised exposure schedule using a double-blind crossover
design. Standard polysomnography was used to measure subsequent sleep,
and in addition, participants were required to provide urine samples
immediately following exposure and upon waking in the morning. A full
dosimetric assessment of the exposure system was also performed in order
to provide sufficient details of the exposure set-up used in the current thesis
and to account for the lack of detailed dosimetric data provided in the
majority of previous studies.
The results of the current study suggest that acute exposure to a mobile
phone prior to sleep significantly enhances electroencephalogram spectral
power in the sleep spindle frequency range compared to the sham exposure
condition. The current results also suggest that this mobile phone-induced
enhancement in spectral power is largely transitory and does not linger
throughout the night. Furthermore, a reduction in rapid eye movement sleep
latency following mobile phone exposure was also found compared to the
sham exposure, although interestingly, neither this change in rapid eye
movement sleep latency or the enhancement in spectral power following
mobile phone exposure, led to changes in the overall quality of sleep.
Finally, the results regarding melatonin suggested that, overall, overnight
melatonin secretion is unaffected by acute exposure to a mobile phone prior
to sleep.
In conclusion, the current study has confirmed that a short exposure to the
radiofrequency electromagnetic fields emitted by a mobile phone handset
immediately prior to sleep is sufficient to induce changes in brain activity in
the initial part of sleep. The consequences or functional significance of this
effect are currently unknown and it would be premature to draw conclusions
about possible health consequences based on the findings of the current
study.
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Dias, Ana Cristina de Freitas. "Uma Linguagem específica do domínio para uma abordagem orientada aos objectivos baseada em KAOS." Master's thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/1960.
Full textAbstract:
Trabalho apresentado no âmbito do Mestrado em Engenharia Informática, como requisito parcial para obtenção do grau de Mestre em Engenharia InformáticaA Engenharia de Requisitos (ER) é o ramo da Engenharia de Software que lida com a identificação,análise, especificação e teste de requisitos para sistemas de software. Um requisito de software é uma propriedade que deve ser exibida pelo software desenvolvido ou adaptado para resolver um determinado problema. Dentro da Engenharia de Requisitos, existem vários ramos de metodologias para obter requisitos, entre os quais a Engenharia de Requisitos Orientada a Objectivos (EROO), que usa objectivos para elicitar, desenvolver, estruturar, especificar, analisar,negociar, documentar e modificar requisitos. A Modelação Específica do Domínio (MED) aumenta o nível de abstracção de uma solução através da utilização de conceitos do domínio em análise. Este tipo de modelação aumenta muito a produtividade pois cada símbolo do modelo corresponde a um conceito do domínio que por sua vez corresponde a um conjunto de linhas de código específico. O problema do domínio pode ser modelado com a recurso a uma Linguagem Específica do Domínio (LED). A complexidade visual de diagramas EROO padrão pode ficar muito grande devido ao elevado número de objectivos a serem refinados e detalhados nos modelos. Este problema acontece tipicamente em sistemas reais devido à sua complexidade inerente podendo torná-los ilegíveis e difíceis de gerir e, como consequência, os modelos podem tornar-se mais difíceis de validar e actualizar. Assim, esta dissertação propõe uma extensão a uma linguagem EROO pela introdução do conceito de Compartimento,uma técnica de encapsulamento para guardar os conceitos e com possibilidade de lidar com técnicas de interface com o utilizador, como a colapsação das caixas que representam os Compartimentos, com o propósito de melhorar a escalabilidade dos modelos. As ferramentas também não verificam a sintaxe dos modelos, o que pode provocar a inconsistência nos mesmos. Para desenvolver a ferramenta foi usada a framework Eclipse (com plugins GMF/EMF). Foi escolhida uma metodologia específica EROO chamada KAOS e baseado nisto foi desenhada uma nova LED através da criação do seu meta modelo estendido.
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Zhou, Weiqian. "Platform for ergonomic steering methods nvestigation of quot Segway-style quot balancing scooters." The University of Waikato, 2008. http://hdl.handle.net/10289/2423.
Full textAbstract:
Segway has been a popular production as an alternative transporter since its invention at the end of 20th century. Millions of people like for its ergonomic design and high-tech elements. It is predicted to be an innovational product to change a person's life style. This thesis focuses on building a simple low cost, home-made Segway style scooter. This project uses two electric scooter motors, two 12V car batteries, one accelerometer and several microprocessors to build up the whole system. Significantly, this project also explains how to build a Brushed Direct Current (BDC) motor driver with a rated output power of more than 350W and the capability of coping with up to 120A transient peak current and up to 40A continuous current. Four-quadrant operation and eight modes of DC motor operation are discussed. A mathematical model of the Segway style scooter is also introduced in details. This including the modelling of a BDC motor, a two-wheeled inverted pendulum and their combination. The linearization of these models is used. At the end the linearized model is simulated in computer software.
34
Matsukevich, I. V., and A. I. Klyndyuk. "Processes Occurring at Preparation of Ca3Co4O9+ Ceramics by Means of Different Solution Methods, and Its Properties." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35255.
Full textAbstract:
By means of complex independent methods the processes occurring at preparation of Ca3Co4O9+ ceram-ics using solid-state reactions and different solution (citrate, polymeric and sol-gel) methods were investi-gated. The crystal structure and microstructure, oxygen stoichiometry, thermal expansion, electrical con-ductivity and thermo-EMF of the samples were studied and values of their power factor were calculated. It is shown that usage of solution methods let us obtain more dense and fine-grained ceramics, which is char-acterized with higher values of electrical conductivity and power factor.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35255
35
Sandström, Malin. "Structural and solid state EMF studies of phases in the CaO-K₂O-P₂O₅ system with relevance for biomass combustion /." Umeå : Energy Technology and Thermal Process Chemistry, Umeå University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-858.
Full text
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Jacobs, Yvonne [Verfasser]. "Vergleichende Untersuchung der Bruchfestigkeiten von verschiedenen EM- bzw. EMF- Gerüsten mit konventionellen und hochexpandierenden Keramikverblendungen mittels des VOSS-Versuchs / Yvonne Jacobs." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2014. http://d-nb.info/1047579367/34.
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Gambetta, Daniele Morco. "Sensorless technique for BLDC motors." University of Southern Queensland, Faculty of Engineering and Surveying, 2006. http://eprints.usq.edu.au/archive/00001427/.
Full textAbstract:
Commutation is a fundamental feature of all DC machines. In conventional DC machines the commutation function is performed by the commutator and brushes. These act as both position sensors and switches. The mechanical commutator has obvious disadvantages. Overcoming those disadvantages has been a major reason behind the development of brushless DC (BLDC) machines. In brushless DC machines commutation is performed by power electronic devices forming part of an inverter bridge. However, switching of the power electronic devices has to be synchronised with rotor position. Position sensing is therefore an essential requirement. This can be done by using sensors such as Hall Effect devices or a sensorless approach may be adopted. Advantages of sensorless techniques include reduced cost and wiring. The most common sensorless method is based on detection of the zero crossing of back EMF signals. But this technique works only above a certain speed since back EMF is directly proportional to speed. As a result BLDC systems which rely solely on back EMF signals for commutation suffer from relatively poor starting performance characterised by back rotation of up to one hundred and eigthty electrical degrees and large fluctuations in electromagnetic torque resulting from non-ideal commutation instants. This may not be acceptable for some applications and many researchers have attempted to overcome those problems. The aim of this project has been to investigate the possibility of a sensorless technique which does not cost more than the back EMF method but with a performance at start-up comparable with that obtained when Hall sensors are used. Initial investigations led to a saliency based method. Detailed theoretical analysis is presented which shows that the method is insensitive to variations in operational parameters such as load current and circuit parameters such as power device voltage drops and winding resistances. There is a close parallel between it and the back EMF method and this makes it easy to swap to the latter method at high speed if necessary. A starting strategy, relying on saliency related measurements, is proposed which offers starting performance much better than the back EMF method and almost as good as Hall sensor based techniques. Experimental evidence is provided to confirm that commutation instants determined by the proposed method are practically coincident with those obtained when Hall sensors are used.
38
Wagnberg, Michael, and Peter Danielsson. "Internal Dashboard." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-77676.
Full textAbstract:
This project is about creating a Dashboard with suitable data models containing support ticket statistics for the company Sigma IT Consulting. The work flow used by Sigma today is to manually log in to the system to see the support ticket statistics, which can be a tedious and time consuming process. Furthermore, Sigma do not have any monitoring system for checking the health of their web application services. They have a need for an internal Dashboard containing this information with regularly updates. Our solution is to design suitable data models and implement them within a Dashboard application.
39
Hung, Ching-Sui. "Effects of pulse-modulated microwave radiation from mobile phones on the sleep/waking EEG and psychomotor vigilance." Thesis, Loughborough University, 2008. https://dspace.lboro.ac.uk/2134/15747.
Full textAbstract:
This study employed multiple assessments, including sleep/resting waking EEG (visual scoring and power spectral analysis) and psychomotor vigilance task, to access effects of varying pulse-modulated microwaves (such as: 'talk', 'listen' and 'standby' mode signals) emitted from a standard mobile phone. The idea was prompted by a finding that the pulse modulation frequencies of mobile phone signals correspond to the frequencies of brain delta and alpha waves. Thereby it is possible the brain is able to recognize and respond to the low-frequency components of the mobile phone signals. Supporting evidence comes from repetitively reported EEG alpha and spindle effects of the 2, 8 and 217-Hz pulsed microwave exposure. Furthermore, brain imaging (EEG and PET) studies reveal 'low-frequency pulse-modulated waves' rather than the 'microwave frequency carrier waves' is the sine qua non for inducing these brain physiological effects [Huber et al., 2002, 2005; Regel et al., 2007a]. On the other hand, recent converging evidence, from molecular, behavioural and electrophysiological level, have shown that brain plasticity is a continuous process from waking to sleep and, sleep, a well-defined physiological condition, is 'shaped' by the waking experiences. The latter findings suggest certain sleep EEG features may characterize levels of cortical plasticity during wakefulness. The work presented in this thesis was inspired by these studies and aimed to understand how the real mobile phone signals with different low-frequency pulsing components [such as 'talk' (8, 217 Hz pulsed), 'listen' (2, 8, 217 Hz pulsed) and 'stand by' mode < 2 Hz pulsed)] change human brain electrical activities from waking to sleep. We approached this question based on EEG analysis in two domains: (1) EEG visual scoring; (2) EEG spectral analysis from relaxed waking to the deeper stages of non-NREM sleep. We also looked at the effects on the psychomotor vigilance performance. Results suggest 'talk' and 'Iisten/standby' modes have inverse effects on the distinctive thalamo-cortical oscillation modes and may thus impart inverse effects on their sleep structures. The implications of this study are of practical importance as it suggests the thalamo-cortical oscillations can be modulated by synchronizing rTMS/tDCS/DBS and sleeplwaking EEG. This concept may be applied to modulate the brain oscillation modes for enhancing sleep-dependent brain plastiCity or information processing.
40
Innangi, Sara <1976>. "Analisi del segnale di backscatter da Ecoscandaglio MultiFascio (EMF) in ambiente marino : applicazioni per lo studio dei fondali e delle risorse ittiche pelagiche in 3D." Doctoral thesis, Università Ca' Foscari Venezia, 2014. http://hdl.handle.net/10579/4660.
Full textAbstract:
L’ambiente marino viene tradizionalmente suddiviso in un dominio bentonico e in un dominio pelagico; in questo lavoro di tesi è stato utilizzato l’Ecoscandaglio MultiFascio (EMF), per investigarli entrambi, utilizzando la risposta acustica (backscatter) dell’onda emessa. E’ stato così applicato lo studio del backscatter in due ambiti scientifici, apparentemente separati tra loro: uno più geologico-sedimentologico e uno più biologico. In particolare, sono state utilizzate nuove metodiche di elaborazione del segnale acustico che hanno portato a nuovi campi di studio e che pongono le basi per successive indagini e ricerche. Lungo il litorale tirrenico lucano il backscatter è stato utilizzato per la caratterizzazione del fondale marino in termini di facies acustiche, mentre lungo la piattaforma continentale dello Stretto di Sicilia è stata analizzata la risposta acustica dell’intera colonna d’acqua per lo studio dei banchi di pesci in tre dimensioni. I risultati hanno portato, in ambito geologico, alla realizzazione di una carta tematica molto dettagliata, oltre che alla creazione di un mosaico acustico in grado di restituire informazioni tessiturali del fondo altamente discriminanti. In ambito biologico le nuove metodiche applicate hanno consentito di visualizzare e descrivere in tre dimensioni i banchi di pesci più abbondanti (Engraulis encrasicolus, Sardina pilchardus) di cui è stata fatta un’analisi della forma, della grandezza e dei volumi.
41
Johansson, Andreas. "FPGA baserad PWM-styrning av BLDC-motorer." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1728.
Full textAbstract:
This thesis work contains a litterature study about electrical motors in general and how PWM-patterns for brushless DC-motors can be made. A suitable method has been implemented as a simulation model in VHDL. A simulation model of a brushless DC-motor which describes the phasecurrents, torque and angular velocity has also been made. The motor model made simulations easier for the complete PWM-system.
The design was synthesised and tested with a prototypeboard including a SPARTAN II FPGA. In order to test the design, a powerstage and a motor was included. The tests showed that the design was working as expected according to the previous simulations.
A study about an alternative way to control a brushless DC-motor has also been made. This alternative is best suited when the generated back-EMK for the motor is sinusoidal. A simulation model for a part of a system like this has been made, and it has been synthesised in order to examine if it is possible to implement using a FPGA availible today.
42
Paese, Evandro. "Conformação eletromagnética de chapas finas usando bobina espiral plana : modelagem com acoplamento eletromagnético." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/108496.
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O presente trabalho trata de uma modelagem eletromagneticamente acoplada e fracamente acoplada ao problema mecânico do processo de conformação eletromagnética (EMF). Este usa bobina espiral plana, aplicada na deformação de chapas finas e planas para obter geometrias finais rasas. Um método de solução numérica é usado para o problema eletromagnético, o qual foi desenvolvido no software Matlab e utiliza o software Abaqus/Explicit para verificação da geometria deformada após a aplicação da força transiente de origem eletromagnética. O método foca especificamente no cálculo da densidade de fluxo magnético em pontos específicos usando a lei de Biot-Savart e análise do circuito que modela o processo de conformação eletromagnética, sendo que as indutâncias deste circuito são calculadas e fazem o acoplamento entre os fenômenos elétricos e magnéticos. Os cálculos das correntes de descarga e induzidas e perfil da força de origem eletromagnética são realizados para o instante inicial, sem considerar o movimento da chapa. O perfil da força de origem eletromagnética ao longo da chapa é calculado para diversos instantes, sendo este um dos dados de entrada no software Abaqus/Explicit através de uma sub-rotina acessível ao usuário (VDLOAD) obtendo-se a geometria da chapa deformada. A rotina de cálculo discretiza o problema eletromagnético como um sistema de equações diferenciais ordinárias (ODE) para calcular a corrente de descarga da bobina atuadora e as induzidas na chapa metálica. Experimentos, sem chapa acoplada, e com chapa fixa ou deformando foram realizados com a aquisição da corrente de descarga, medição da densidade de fluxo magnético, velocidade de deformação e geometria da chapa deformada, demonstrando uma boa correlação com o método de cálculo proposto. O presente trabalho fornece importantes informações para o projeto de sistemas de conformação eletromagnética sem a necessidade de uma função da corrente de descarga como dado de entrada para solução do problema eletromagnético.This thesis deals with modeling and numerical simulation electromagnetically coupled and loosely-coupled to the mechanical problem for process of the electromagnetic forming. This uses flat spiral coil, applied to the deformation of thin and flat sheet metal to obtain shallow end geometries. This method uses a numerical solution to the electromagnetic problem, which was developed in the software Matlab and uses the software Abaqus/Explicit for verification of the deformed geometry after applying of the transient force of origin electromagnetic. The method focuses specifically on the calculation of the magnetic flux density at specific points using the Biot-Savart law and circuit analysis that modeling of electromagnetic forming process and the inductances of this circuit are calculated and couple the electric and magnetic phenomena. Calculations of discharge and induced currents, profile force of origin electromagnetic are performed for the initial time, without considering the motion of the sheet metal. The profiles force of origin electromagnetic along the sheet metal is calculated for several instants, which are input data in software Abaqus/Explicit using a user-routine (VDLOAD) obtaining the deformed geometry of the sheet metal. The calculation routine discretizes the electromagnetic problem as a system of ordinary differential equations (ODE) to calculate the discharge current of the actuator coil and induced currents in the metal sheet. Experiments without coupled sheet metal, and fixed or deforming sheet metal were performed with the acquisition of the discharge current, measurement of magnetic flux density, velocity of movement and deformation geometry of the sheet metal, demonstrating a good correlation with the proposed method of calculation. This study provides important information for the design of the electromagnetic forming systems without the need for a function of discharge current as input for solution of the electromagnetic problem.
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Netočný, Ondřej. "Nástroj pro grafické prototypování systémů na čipu." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2013. http://www.nusl.cz/ntk/nusl-235453.
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This thesis deals with design and implementing of a tool for development of MPSoC (multiprocessor systems on chip). It is going to apprise the reader with this matter and introduces several ways how to solve these issues in Codasip Studio IDE (integrated development environment). The graphical editor for multicore system development and a set of support tools for fast and effective development are introduced in this thesis. These are mainly interactive wizards which help user to start new projects. To handle the subject matter it is necessary to understand CodAL language, Eclipse IDE, GMF (Graphical Modeling Framework) and EMF (Eclipse Modeling Framework) which are used for graphical editor implementation.
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Pohlers, Michael. "Generierung und Analyse EMA/E2F-6-defizienter Mäuse." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=978268954.
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Pohlers, Michael. "Generierung und Analyse EMA/E2F-6-defizienter Mäuse." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2005. http://dx.doi.org/10.18452/15393.
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The present study focuses on the biological functions of the transcription factor EMA/E2F-6, a member of the E2F-family of transcription factors that play an import role in cell cycle progression, differentiation and apoptosis. EMA/E2F-6 functions as a transcriptional repressor by recruiting a large protein complex, that includes polycomb group proteins, to specific target genes in order to silence their expression. To identify the biological functions of EMA/E2F-6 mice lacking this factor were developed and subsequently analysed. EMA/E2F6-/- mice are born with the expected frequency, are fertile and develop normally up to 18 months of age. Then about 25 % of these mice develop a paralysis of the hind limbs and present with a severe primary myelination defect of the spinal cord (and in part of peripheral nerves, too) that is accompanied by a massive infiltration of macrophages. Importantly, the histological findings were also detected in EMA/E2F-6-/- mice lacking clinical symptoms albeit to a lesser extend. With respect to EMA/E2F-6 association with polycomb group (Pc-G) proteins there were no significant findings such as skeletal transformations. In addition, only a mild proliferation defect of T-lymphocytes was observed that, in a more severe form, is typical for Pc-G mutations in the mice. Surprisingly, embryonic fibroblasts from EMA/E2F-6-/- mice have no obvious cell cycle defects. Accordingly, gene expression profiles showed that classical E2F target genes were normally regulated in these cells. However, EMA/E2F-6-/- fibroblasts ubiquitously express genes like alpha-tubulin-3 and -7 that are normally expressed in a strictly testis-specific manner. All EMA/E2F-6-dependent target genes identified contain a conserved E2F-binding site in their promoters that is required both for EMA/E2F-6 binding and regulation.
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Bürger, Christoff, and Sven Karol. "Towards Attribute Grammars for Metamodel Semantics." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-71807.
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Of key importance for metamodelling are appropriate modelling formalisms. Most metamodelling languages permit the development of metamodels that specify tree-structured models enriched with semantics like constraints, references and operations, which extend the models to graphs. However, often the semantics of these semantic constructs is not part of the metamodel, i.e., it is unspeci ed. Therefore, we propose to reuse well-known compiler construction techniques to specify metamodel semantics. To be more precise, we present the application of reference attribute grammars (RAGs) for metamodel semantics and analyse commonalities and differences. Our focus is to pave the way for such a combination, by exemplifying why and how the metamodelling and attribute grammar (AG) world can be combined and by investigating a concrete example - the combination of the Eclipse Modelling Framework (EMF) and JastAdd, an AG evaluator generator.
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Silva, Christian Egidio da. "Efeito do tratamento térmico e da composição química nas propriedades mecânicas e capacidade de recuperação de forma de ligas inoxidáveis Fe-Mn-Si-Cr-Ni com EMF." Instituto Tecnológico de Aeronáutica, 2013. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=2839.
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Neste trabalho é apresentado o efeito do tratamento térmico e da composição química de aços inoxidáveis Fe-Mn-Si-Cr-Ni com Efeito de Memória de Forma (EMF) processados por forjamento nas propriedades mecânicas e capacidade de recuperação de forma. As amostras foram caracterizadas em termos da evolução microestrutural, propriedades mecânicas, desgaste e recuperação de forma. A caracterização microestrutural foi realizada com o auxílio de técnicas de microscopia óptica e microscopia eletrônica de varredura. Foram realizadas medições de dureza nas diferentes condições de estudo para compreender a evolução do encruamento e amolecimento das amostras tratadas termicamente em diferentes temperaturas. A caracterização do EMF foi realizada por meio de ensaio de compressão, sendo aplicadas deformações de 4% e 6%, e do mecanismo de desgaste foi realizada por meio de ensaio do tipo pino contra lixa. Empregou-se a técnica de calorimetria diferencial de varredura para determinar as temperaturas de transformação de fase. O aumento da temperatura de austenitização e do tempo de patamar promoveu um aumento do tamanho de grão austenítico. A liga com maiores teores de cromo e níquel e menor teor de manganês apresentou menor crescimento de grão, maiores valores de dureza e de tensão de escoamento, independente da temperatura de austenitização utilizada, e melhor resistência ao desgaste. Também foi evidenciado, para esta liga, um contínuo incremento da máxima tensão em compressão à medida que a temperatura de austenitização aumentou, independente da deformação aplicada durante o ensaio de compressão. Comportamento exatamente inverso foi observado para a liga com menores teores de cromo e níquel e maior teor de manganês. Ao aumentar a temperatura de austenitização, independente da composição química, ocorreu uma redução significativa de dureza, mas não foi observada alteração da tensão de escoamento, que até apresentou um pequeno aumento. As ligas estudadas apresentaram resultados de módulo de elasticidade estatisticamente iguais mesmo com a diferença de composição existente. A alteração da temperatura de revenimento não implicou em mudança significativa de dureza. No entanto, a liga com maiores teores de cromo e níquel e menor teor de manganês apresentou aumento de dureza após o revenimento, comportamento exatamente oposto às demais ligas estudadas. Na análise microestrutural observou-se o aparecimento de pequenos precipitados ricos em cromo e silício, o que confirma a ocorrência de endurecimento secundário para esta liga. Este efeito parece ser tanto maior quanto maior é a temperatura de austenitização utilizada. A liga com menores teores de cromo e níquel e maior teor de manganês apresentou melhor capacidade de recuperação total independente da deformação aplicada. Comprovou-se que, se a resistência mecânica da matriz é menor, obtém-se uma melhor capacidade de recuperação de forma. Para este material, a contribuição da recuperação de forma supera a contribuição associada à recuperação elástica. Obteve-se uma recuperação total de 3,9% para a liga com menores teores de cromo e níquel e maior teor de manganês ao ser aplicada deformação de 6%, resultado obtido quando a austenitização foi realizada a 950C. Esta liga não apresentou variação significativa nas temperaturas de transformação de fase independente da temperatura de austenitização empregada.
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Funk, Richard H. W., and Thomas K. Monsees. "Effects of Electromagnetic Fields on Cells: Physiological and Therapeutical Approaches and Molecular Mechanisms of Interaction." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-136228.
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This review concentrates on findings described in the recent literature on the response of cells and tissues to electromagnetic fields (EMF). Models of the causal interaction between different forms of EMF and ions or biomolecules of the cell will be presented together with our own results in cell surface recognition. Naturally occurring electric fields are not only important for cell-surface interactions but are also pivotal for the normal development of the organism and its physiological functions. A further goal of this review is to bridge the gap between recent cell biological studies (which, indeed, show new data of EMF actions) and aspects of EMF-based therapy, e.g., in wounds and bone fracturesDieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
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Srna, Pavol. "Nástroj pro návrh čipu v UML." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2010. http://www.nusl.cz/ntk/nusl-235538.
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This paper deals with the creation of the tool for chip design in UML. The intention of this work is to present the news in the UML language version 2.0, that can be possibly used for modeling of embedded systems. Furthermore, it deals with the possibility and method of modeling in the Eclipse environment and it focuses on the Eclipse Modeling Framework. This work explains the principle of developing of graphical editors based on GMF used fully by developing tool. Finally, it discusses the chosen solution.
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Hedlund, Tobias. "EMC/EMI i solcellssystem : Minimering av elektromagnetiska störningar från solcellsanläggning." Thesis, Karlstads universitet, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-85086.
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This report presents a theoretical background to electromagnetic interference from photovoltaic systems that use power optimizers. The purpose is to carry out measurements at an existing facility to analyze and discuss appropriate measures to minimize disturbance levels. The work is designed by Glava Energy Center (GEC) and measurements are carried out together with the Swedish Electrical Safety Agency (Elsäkerhetsverket) and Rencke's El & Mätteknik. The report concludes with the results of measurement and a discussion of appropriate measures to achieve electromagnetic compatibility (EMC), designed for the specific facility. Finally, a brief discussion is given about future work in this area.