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Validation of ModelicaML modelsGatla, Goutham January 2012 (has links)
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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Wireless electromagnetic radiation assessment based on the specific absorption rate (SAR): A review case studyAbdul-Al, Mohamed, Amar, A.S.I., Elfergani, Issa T., Littlehales, R., Ojaroudi Parchin, Naser, Al-Yasir, Yasir I.A., See, C.H., Zhou, D., Abidin, Z.Z., Alibakhshikenari, M., Zebiri, C., Elmegri, Fauzi, Abusitta, M.M., Ullah, Atta, Abdulssalam, Fathi M.A., Rodriguez, Jonathan, McEwan, Neil J., Noras, James M., Hodgetts, Russell, Abd-Alhameed, Raed 15 February 2022 (has links)
Yes / Employing electromagnetic fields EMFs) in new wireless communication and sensing technologies has substantially increased the level of human exposure to EMF waves. This paper presents a useful insight into the interaction of electromagnetic fields with biological media that is defined by the heat generation due to induced currents and dielectric loss. The specific absorption
rate (SAR) defines the heating amount in a biological medium that is irradiated by an electromagnetic field value. The paper reviews the radio frequency hazards due to the SAR based on various safety standards and organisations, including a detailed investigation of previously published work in terms of modelling and measurements. It also summarises the most common techniques utilised
between 1978 and 2021, in terms of the operational frequency spectrum, bandwidth, and SAR values. / The European Union’s Horizon 2020 innovation programme under grant agreement H2020- MSCA-ITN-2016 SECRET-722424 and the U.K. Engineering and Physical Sciences Research Council (EPSRC) under grant EP/E022936/1 supported this research. This study is also sponsored by the FCT/MEC through national funds and, where applicable, co-financed by the ERDF under the PT2020 Partnership Agreement under the UID/EEA/50008/2020 project. This study is part of the POSITIONII project, which is funded by the European Commission’s Joint Undertaking under the grant number Ecsel-7831132-Postitio-II-2017-IA. Moreover, this paper is also partially funded by British Council “2019 UK-China-BRI Countries Partnership Initiative” programme, with project titled “Adapting to Industry 4.0 oriented International Education and Research Collaboration”. In addition, this project has received funding from Universidad Carlos III de Madrid and the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant 801538.
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Caractérisation du champ proche électromagnétique et exposition professionnelle aux ondes RF en milieu industriel / Electromagnetic Near-field Characterization & Occupational Exposure to RF Waves in Industrial EnvironmentJomaa, Kassem 14 December 2018 (has links)
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 réelles. / The 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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The efffects of eletromagnetic fields emitted by mobile phones on human sleep and melatonin productionLoughran, Sarah Patricia, n/a January 2007 (has links)
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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Thermodynamic properties of liquid Al-Sn-Zn alloysChen, Bang-Yan 20 August 2012 (has links)
none
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Program pro export vektorových obrázků z Autodesk Eagle / Vector image export program for Autodesk EagleSičkaruk, Roman January 2019 (has links)
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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Direct Back EMF Detection Method for Sensorless Brushless DC (BLDC) Motor DrivesShao, Jianwen 18 September 2003 (has links)
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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Софтверски систем за каталогизацију по MARC 21 формату / Softverski sistem za katalogizaciju po MARC 21 formatu / Software system for MARC 21 cataloguingDimić Surla Bojana 28 December 2009 (has links)
<p>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 алату<br />235 MagicDraw верзија 16.0 који подржава UML 2.0. Имплементација је реализована коришћењем Eclipse plug-in технологије и програмског језика Јава.</p><p>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. </p><p><span style="font-size: 12px;">Извршено је проширење основног едитора додатним </span><span style="font-size: 12px;">функционалностима система за каталогизацију: приказ </span><span style="font-size: 12px;">података о библиографском формату, унос локацијских </span><span style="font-size: 12px;">података, експорт и импорт записа, приказ каталошких </span><span style="font-size: 12px;">листића и библиотечко окружење. </span></p><p>Коришћењем RCP технологије генерисана је софтверска компонента за каталогизацију која се може користити у различитим библиотечким информационим системима.</p> / <p>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 alatu<br />235 MagicDraw verzija 16.0 koji podržava UML 2.0. Implementacija je realizovana korišćenjem Eclipse plug-in tehnologije i programskog jezika Java.</p><p>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. </p><p><span style="font-size: 12px;">Izvršeno je proširenje osnovnog editora dodatnim </span><span style="font-size: 12px;">funkcionalnostima sistema za katalogizaciju: prikaz </span><span style="font-size: 12px;">podataka o bibliografskom formatu, unos lokacijskih </span><span style="font-size: 12px;">podataka, eksport i import zapisa, prikaz kataloških </span><span style="font-size: 12px;">listića i bibliotečko okruženje. </span></p><p>Korišćenjem RCP tehnologije generisana je softverska komponenta za katalogizaciju koja se može koristiti u različitim bibliotečkim informacionim sistemima.</p> / <p> 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.</p>
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應用模型驅動架構於多平台導引精靈程式開發 / Apply Model-Driven Architecture to the Development of Multi-Platform Wizards郭建宏, Kuo, Chien Hung Unknown Date (has links)
導引精靈(wizard)是一種用來收集用戶端資料的互動式使用者介面應用程式,常被廣泛的使用在軟體系統裡,也是大多數應用程式常見的功能之一。導引精靈的使用不僅簡化了複雜的資料收集過程,也可以避免資料的遺漏以確保收集資料的完整性;此外在資料收集的過程中導引精靈所提供的適當提示與即時資料驗證,還可以提高資料收集的正確性,所以導引精靈對於應用程式的資料收集是相當有用的。
本研究的目標是開發一個模型驅動的導引精靈開發系統,希望能在相同或不相同的時間裡快速建構多平台導引精靈程式。我們提出的系統稱為MoDWiz,它實現了應用「模型驅動架構(MDA)」於多平台導引精靈開發的所有工具支援。為了讓使用者建構自己的(平台無關)導引精靈模型,MoDWiz不僅提供了用以規範導引精靈的超模型,還制定一個特定領域語言WDL以作為此超模型的具體語法。此外,由於WDL的制定,我們得以提供專屬的編輯器以輔助使用者進行導引精靈模型的編輯。目前MoDWiz支援三種執行平台的導引精靈開發,分別為網頁應用程式、Eclipse與Java。而根據MDA理論,我們必須制定的三種平台超模型均已內含於MoDWiz。除此之外,MoDWiz的工具鏈還包括用來將平台無關導引精靈模型轉換成符合每一個特定平台導引精靈模型的M2M工具,以及將每一個特定平台導引精靈模型轉換成相對應實作的M2T工具。所有MoDWiz的工具與WDL編輯器程式均實作為Eclipse 外掛程式,因此能夠與Eclipse平台高度整合。當利用WDL編輯器完成導引精靈模型的製作之後,使用者只需透過簡單的滑鼠點擊就可以完成導引精靈程式的實作。 / A wizard is an interactive user interface program used to collect data from the user. It is widely used in software systems and is a common part of most applications. Not only does the use of wizards modularize and simplify complex data collection process, but it can also avoid data missing and ensure data integrity. Furthermore, during the process of data collection, since a wizard can provide tips and instant data validation it can also improve the correctness of collected data. As a conclusion, it is very beneficial to use wizards in an application.
The goal of this research is the development of a model-driven wizard generation system (MoDWiz) that can be used to help rapid construction of multi-platform wizards to be developed at different or the same time. MoDWiz is our solution to the problem of applying OMG's model-driven architecture (MDA) to the development of multi-platform wizards. In order for the user to construct his (platform independent) wizard model, MoDWiz provides not only a wizard metamodel but also a domain specific language (DSL) called WDL as a concrete syntax of the metamodel. Owing to the availability of WDL, we are able to provide also a friendly editor to help the user to edit his wizard models. MoDWiz supports at present three platforms: eclipse platform, web application platform and plain Java platform. Accordingly metamodels of wizards for these platforms have to be defined and indeed have been provided in MoDWiz. Apart from these, MoDWiz's tool chain includes also M2M tools, which could transform every platform independent wizard model into a corresponding PSM model for each platform, as well as M2T tools, which could transform every platform specific wizard model into a corresponding implementation. All of MoDWiz's tools and wizard editor are implemented as eclipse plug-ins and thus are highly integrated with eclipse. As a result it is very easy to get a wizard implementation by simple mouse clicks once its model has been constructed using MoDWiz.
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DC Motor driver for low RPMKetelaars, Stefan January 2016 (has links)
For this project the main goal was to design, simulate, build and test a DC motor driver. To accomplish this four specific parts had to be design. First a DCDC converter that converts the input signal from an external power supply in a controllable DC output. The second part was a DCDC converter that converts the DC input in a voltage useful for the function generator, the third part is the function generator that provides a signal to the H-Bridge, and the final part is the H-Bridge itself. The goal is to compare the measurement with the simulations to the expectations. What we are interested in is the influence of EMF when the RPM of the motor is zero or close to zero.
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