Measured and simulated distributions of voltage and temperature along stator coils of synchronous generator

The ECP (end winding corona protection) of the armature coils of a synchronous generator is designed and modeled. The paper focuses on the distribution of voltage and temperature along this protection that is both measured and simulated. The results are compared. The aim of the work is to verify the suggested mathematical model which would help to save time and costs connected with the ECP design

The Design of Wiring and Alarm System for a Residential Building

Předkládaná diplomová práce se zabývá projektováním elektroinstalace a elektronického zabezpečovacího systému (EZS) rodinného domu a zároveň je v diplomové práci popsán návrh automatického otevírání brány k pozemku. Diplomová práce seznamuje s obecnými požadavky na projektování, odbornou způsobilostí projektantů a s jednotlivými fázemi projektové dokumentace dle stavebního zákona. Obsahuje stručný teoretický rozbor jednotlivých prvků elektroinstalace a EZS vybraných z aktuální nabídky. Dále posuzuje možnosti automatického otevírání brány k pozemku rodinného domu. Za současného dodržování aktuálních technických norem řešící tuto problematiku poskytuje návrh a projektování elektroinstalace včetně TV/SAT rozvodu, LAN sítě a EZS rodinného domu. Dále obsahuje návrh automatického otevírání brány k pozemku rodinného domu. Na závěr je v diplomové práci provedena ekonomická rozvaha celého navrženého projektu.Katedra technologií a měřeníObhájenoSubmitted magister thesis is focused on the projection of the electrical installation and the electronic security system (EZS) of the family house. Simultaneously there is described the suggestion of the automatic opening of the gateway. It mentions general requirements to the projection, professional competence of draughtsmen and the description of particular periods of the contract documents in accordance with the building act. It introduces brief theoretical analysis of individual elements of the electrical installation and EZS that were chosen from the current offer. This work also judges options for the automatic opening of the gateway. It provides a design and the projection of the electrical installation inclusive of TV/SAT distribution, LAN network and EZS of the family house while respects the current technical standards addressing this issue. It also includes a proposal for the automatic opening gateway. At the end this work contains the economical balance of the whole proposed project

Elektrostatický separátor plastových materiálů

Disertační práce se zabývá elektrostatickým separátorem plastových materiálů. V úvodu je zaměřena na současné problémy plastového odpadového hospodářství, s tím spojenou nutností separace směsí plastových materiálů, současné technologie a principy elektrostatické separace plastových materiálů a důvody, proč byl zvolen pro téma této práce právě free-fall elektrostatický separátor. Po formulaci problému je v práci definován matematický model free-fall elektrostatického separátoru, který je následně numericky řešen. Je zde představen experimentální jednostupňový free-fall elektrostatický separátor (později po přestavbě i experimentální dvoustupňový free-fall elektrostatický separátor), který byl v rámci této práce vyvinut na základě řešeného numerického modelu, a také stručně popsáno jeho základní konstrukční uspořádání. Dále je na tomto zařízení proveden experiment s cílem ověřit funkčnost a technologii free-fall elektrostatického separátoru, kdy výsledky experimentu jsou porovnány s výsledky řešeného numerického modelu. V práci je vykonán také experiment na separaci plastové směsi, kde byla zkoumána účinnost a čistota výsledné separace. Dále v rámci experimentů se zařízením byly zkoumány vlivy teploty a vlhkosti na vlastní proces separace a v důsledku toho zkoušeno vysoušení směsi plastových částic před jejich nabíjením a vlastní separací. Poté následovaly jiné experimenty na zjištění rozložení elektrického náboje ve vzorku částic a rychlosti částic, při které již částice nejsou významně vychylovány elektrickým polem. Další výzkum navázal na předchozí prvotní experimentální měření a došlo k vykonání více nových experimentálních měření s různými autorovi dostupnými druhy plastů, za účelem zjištění skutečnosti, které plasty je vhodné od sebe separovat a které nikoliv. Jako poslední je v práci učiněna přestavba původního experimentálního jednostupňového free-fall elektrostatického separátoru na nový experimentální dvoustupňový free-fall elektrostatický separátor, aby se mohly vykonat poslední experimenty na ověření i této technologie dvoustupňového free-fall elektrostatického separátoru a prozkoumání, zdali lze s touto technologií dosáhnout ještě lepších výsledků účinnosti a čistoty elektrostatické separace plastových materiálů.ObhájenoThe dissertation deals with the electrostatic separator of plastic materials. In the introduction there are mentioned the current problems of the plastic waste management, coupled with the necessity of separation of mixtures of plastics materials, current technologies and principles of electrostatic separation of plastic materials and the reasons why the free-fall electrostatic separator was chosen as a topic of this work. After formulation of the problem, in the work is defined the mathematical model of the free-fall electrostatic separator, which is then solved numerically. There is introduced the experimental one-stage free-fall electrostatic separator (later after the reconstruction even experimental two-stage free-fall electrostatic separator), which was developed within this work and is based on solved numerical model, and briefly described its basic structural arrangement. Further, it is with this device performed an experiment with the aim to verify the functionality and technology of free-fall electrostatic separator when the results of the experiment are compared with the results of solved numerical model. In the work is also carried out an experiment for the separation of a plastic mixture, where was studied the efficiency and purity of the resulting separation. Moreover, in the experiments with the device were investigated the effects of temperature and humidity on the respective separation process and consequently tested drying of the mixture of plastic particles prior to their own charging and respective separation. Then, there were other experiments to determine the distribution of electrical charge in the sample of particles and the velocity of particles at which the particles were no longer significantly deflected by the electric field. Further research has been linked to previous initial experimental measurements and more new experimental measurements have been carried out with different types of plastic available to author in order to find out the fact which plastics are appropriate to separate from each other and which are not. The last one in the work is made the reconstruction of the original experimental one-stage free-fall electrostatic separator into the new experimental two-stage free-fall electrostatic separator in order to perform the latest experiments to verify even technology of the two-stage free-fall electrostatic separator and to explore if this technology is able to achieve even better results of efficiency and purity of electrostatic separation of plastic materials

Experimental electrostatic separator for plastic mixture

The paper deals with the verification of the experimental electrostatic separator. Some individual industrial plastic materials are experimentally verified for finding of the direction of deflection of particles. On this basis it is selected one mixture of particles for the verification of functionality of this experimental device. A mixture consisting of thermoplastic copolyester (TPC) and the acrylonitrile butadiene styrene (ABS) is used for the experiment. The goal of the experiment is to find out a efficiency and a purity of the separation

Experimental Study of Triboelectric Separator for Mixture of Plastic Particles

A device for electrostatic separation of triboelectrically charged plastic particles is experimentally verified. A mixture consisting of high-density polyethylene (HDPE) and polymethyl methacrylate (PMMA) is used for the experiment. The goal of the experiment is to find out the efficiency and purity of the separation

Impact of Humidity on Efficiency of Triboelectric Separator for Mixture of Plastic Particles

A device for electrostatic separation of triboelectrically charged plastic particles is experimentally verified. A mixture consisting of high-density polyethylene and polymethyl methacrylate is used for the experiment. The goal of the experiment is to find out the efficiency of the separation depending on the temperature and humidity of the air in the charger, because the high humidity deteriorates the efficiency of the device

Area of the right atrium of the fetal heart and its significance in fetuses with tricuspid regurgitation

Objectives: The first aim was to develop a nomogram for the area of the right atrium (ARA) of the fetal heart in uncomplicated singleton pregnancies. The second aim was to assess diagnostic indices of ARA to distinguish between tricuspid regurgitation (TR) with and without concomitant congenital heart defect (CDH). Methods: The study was conducted between 2014 and 2019. Fetal echocardiography was performed on fetuses with and without TR. For the first aim, ARA was measured in 460 fetuses without proven structural and chromosomal abnormalities, and for the second aim, ARA was measured in 1077 fetuses with TR. Results: A nomogram for the ARA of fetuses with normal hearts was developed. TR was observed in 4.5% (1077/23,771) of euploid fetuses; 4.3% (1020/23,771) of fetuses had TR without a concomitant CHD, and 0.2% (57/23,771) fetuses had TR with a concomitant CHD. No significant differences in ARAs were found between fetuses with normal hearts without TR (n = 22,694) and fetuses with TR without CHD (n = 1020; p = .751). Fetuses with TR and CHDs had different ARA than fetuses with normal hearts without TR and fetuses with TR without CHD (p < .0005 in both cases). Conclusions: ARA seems to be an auxiliary marker to distinguish the presence of CHD in fetuses with TR.Web of Scienc

Parents’ request for termination of pregnancy due to a congenital heart defect of the fetus in a country with liberal interruption laws

Objectives:This study aimed to evaluate the prenatal rate of congenital heart defects (CHDs) and the frequency of termination of pregnancy (TOP) due to a CHD, depending on the severity of the defect and concomitant diseases of the fetus. Methods:The data were assessed retrospectively between 2002 and 2017. Ultrasound examination was performed mostly in the second trimester. For analysis, the CHDs were divided into three groups of severity and three groups of fetus impairment. Results:A total of 40,885 fetuses underwent echocardiography. The CHDs were detected in 1.0% (398/40,885) and were an isolated anomaly in 69% (275/398). Forty-nine percent (197/398) of families decided to TOP. In all groups of severity, the rate of TOP rose linearly when comparing isolated defects and cases with associated morphological and genetic impairments. The TOP was significantly dependent on the associated anomalies in patients with the most correctable defects (p < .001) and the severity of CHDs in isolated cases without any other impairment (p < .001). Conclusion:The parents' decision to terminate increased with the severity of the defect and the associated anomalies of the fetus. The parents were mostly influenced by the associated anomalies when the CHD was correctable, and genetic factors played a more important role than morphological ones.Web of Science33172926291