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Heart rhythm disorders represent a significant global health concern, affecting millions of people worldwide and serving as a risk factor for heart failure. Despite the prevalence of these arrhythmias, broadly effective treatments remain elusive. In this work, we present the cardiac conduction system as an excitable medium whose dynamics can be described with simple mathematical models. We show that the excitation of this system can become altered through well-timed stimuli which create persistent rotational activation patterns. We describe the hypothesized relationship between these patterns and the perpetuation of fibrillation, discussing the fragmenting state of multi-wavelet reentry as well as the theory of mother rotors. To distinguish between potential mechanisms, we present results using concepts of phase synchrony to characterize clinical recordings of fibrillation. Such analysis implies a level of spatiotemporal stability inconsistent with a mechanism exclusively comprised of chaotic multi-wavelet reentry. Moreover, we outline a technique to determine continuously updating vector flow fields which align with the direction of local conduction. We show that this methodology can be used to determine the source of rotational and focal excitation patterns in an automated fashion, providing a useful means to interpret otherwise complex spatiotemporal maps. Finally, we describe the spontaneous termination of fibrillation as a stochastic event, and construct a birth-death Master equation for the number of spiral tips n during the turbulent state of spiral-defect chaos. Within this framework, we can infer important statistical quantities related to fibrillation such as the mean number of spiral tips n, the quasi-stationary distribution Pqs, and the mean episode duration t. Our results imply that t scales exponentially with the area A. We derive this scaling law using a WKB approach, which yields an effective Hamiltonian describing tip density q = n=A and fluctuation momentum p. This stochastic approach can accurately predict t, even for systems in which a multitude of episodes cannot be simulated due to prohibitive computational cost.

V magistrskem delu je predstavljena izvedba osnovnega sistema za avtomatizacijo pametnega doma. Poudarek je na uporabi brezplačne odprtokodne rešitve in na izgradnji modularne osnove z možnostjo enostavne nadgradnje na podlagi želja in potreb uporabnika. Obravnavane so vse prednosti takega sistema in razloženo je delovanje vseh povezav med gradniki. Domača avtomatizacija ali pametni domovi pomenijo uvajanje novih tehnologij v domače okolje z namenom, da se uporabnikom ponudi dodatne prednosti na ravni udobja bivanja. V magistrsko nalogo je najprej vključen opis pametnega doma in IoT naprav. Sledijo opis protokolov za primerljive mikro sisteme in primeri komercialnih naprav, ki so dostopne na trgu. Jedro sistema sta mikroračunalnik Raspberry PI in openHAB programska oprema, ki skrbi za celotno delovanje in komunikacijo v sistemu. Predstavljena sta dva primera z izdelano generično napravo v obliki senzorja temperature in vlage, in sicer v povezavi z razvojno ploščico NodeMCU. Predstavljena je tudi povezava komercialne naprave s podporo MQTT protokola. Prav tako je obravnavana komunikacijska metoda objavi/naroči, ki je jedro MQTT protokola in prenašanja informacij znotraj opisanega primera. V sistem spada tudi vmesnik na pametnem telefonu ali tablici za preprosto spremljanje in upravljanje vseh priključenih naprav. V zadnjem delu je še so še prikaz s primeri in možnosti razširitve. The master's thesis presents the implementation of the basic system for smart home automation. The emphasis is on the use of a free open source solution and on the construction of a modular base with the possibility of easy upgrades, according to the wishes and needs of the user. Through the work, all the advantages of such a system are presented and the operation of all connections between the building blocks is explained. Home automation or smart homes mean the introduction of new technologies into the home environment in order to offer users additional benefits in the form of living comfort. At the beginning is a description of a smart home and IoT devices. The following is a description of protocols for comparable micro systems and some examples of commercial devices on the market. The core of the system is the Raspberry PI microcomputer and openHAB software, which takes care of the entire operation and communication in the system. Two examples are presented with a manufactured generic device in the form of a temperature and humidity sensor, in conjunction with NodeMCU development board, and the connection of a commercial device with MQTT protocol support. Also presented is the publish / subscribe communication method, which is the core of the MQTT protocol and the transfer of information within the described case. The system also includes an interface on a smartphone or tablet for easy monitoring and management of all connected devices. In the last part there is a description with examples for expansion options.

V magistrski nalogi je predstavljen vpliv poliuretanske pene na dušenje nosilnih struktur. Raziskovalo se je, v kolikšni meri poliuretanska pena zmanjša amplitude nihanja cevnih jeklenih nosilcev. Najprej je predstavljen analitični izračun lastnih frekvenc nosilca po Euler-Bernoullijevi teoriji upogibnega nihanja nosilcev. Izbrani nosilec je cev kvadratnega prereza, ki je na eni strani fiksno vpet, na drugi strani pa ima prosti konec. V programu NX Nastran se je po metodi končnih elementov izvedla modalna analiza nosilca, pri kateri so rezultat lastne oblike in lastne frekvence nosilca s polnilom in brez polnila iz poliuretanske pene. Teoretično pridobljeni rezultati so se preverili še z eksperimentom. Nihanja preizkušancev s polnilom in brez polnila iz poliuretanske pene, so bila izmerjena s pospeškomerom ADXL377 in s hitrotekočo kamero Fastcam Photron Ultima 512. V rezultatih raziskave je predstavljen vpliv polnila iz poliuretanske pene na povečanje dušilnih karakteristik jeklenih cevnih nosilcev. V prilogi je dodan izpis analitičnega izračuna lastnih frekvenc nosilca po Euler-Bernoullijevi teoriji upogibnega nihanja nosilcev, ki je narejen v programu Mathematica. The master's thesis introduces the influence of polyurethane foam on the damping of beam structures. It was researched, how much polyurethane foam reduces the amplitudes of vibrations of tubular steel beams. At first is introduced an analytical calculation of the natural frequencies of the beam based on the Euler-Bernoulli theory of bending oscillation of the beams. The selected hollow square cross-section beam is fixed on one side and on the other side it has the free end. With the finite element method in the NX Nastran software is carried out the modal analysis of the beam that results are natural shapes and natural frequencies of beam with filling and without filling from polyurethane foam. Theoretically gained results were also checked with experiment. The vibrations that appear on prepared samples with filling and without filling from polyurethane foam, were measured out with an accelerometer ADXL377 and with the high speed camera Fastcam Photron Ultima 512. In results of research is presented influence of filling from polyurethane foam to increase damping characteristics of the tubular steel holder. In attachment is added the display of the analytical calculation of the natural frequencies according to the Euler-Bernoulli theory of bending oscillation of the beams, which is made in the Mathematica software.

To diplomsko delo obsega opis, izdelavo in primerjavo dveh različic enake aplikacije za izris geografskega položaja oddaljene mobilne naprave. Prva različica aplikacije je izdelana izključno za mobilne naprave s operacijskim sistemom Android, druga različica pa je spletna različica, ki je neodvisna od platforme. V prvem delu se osredotočamo predvsem na tehnologije in orodja, ki smo jih uporabljali pri izdelavi aplikacij. Opisali smo sistem GPS, aplikativni sistem Google Maps, spletne tehnologije, operacijski sistem Android, razvoj aplikacij za takšne sisteme ter razvojno orodje Android Studio. V drugem delu smo opisali načrtovanje in izdelavo naše aplikacije za določanje geografskega položaja oddaljene mobilne naprave. Aplikacija ima možnost oddajanja podatkov o našemu trenutnemu geografskemu položaju ter možnost prejemanja podatkov o geografskemu položaju neke druge mobilne naprave. Prejeti geografski položaj nam aplikacija izriše na zemljevidu. Na koncu smo obe različici aplikacije testirali in ju primerjali ter opisali naša opazovanja. This thesis covers a description, creation and comparison of two different versions of the same application for tracing the geographic position of a remote mobile device. The first version of the application is made exclusively for mobile devices with the operating system Android the second version is an online version, which is independent of the platform. In the first part of thesis, we mainly focus on the technology and the tools that were used to create the applications. We described the GPS system, application system Google Maps, web technologies, operating system Android, the development of applications for such systems and the development tool Android Studio. In the second part, we described the design and creation of our application for determining a geographic position of a remote mobile device. The application has the ability to broadcast the information of our current geographical position and the ability to receive the data of geographical position of some other mobile device. The application draws the received geographical position on the map. In the last part, we tested both application versions, compared them and described our observations.

This thesis covers a description, creation and comparison of two different versions of the same application for tracing the geographic position of a remote mobile device. The first version of the application is made exclusively for mobile devices with the operating system Android; the second version is an online version, which is independent of the platform. In the first part of thesis, we mainly focus on the technology and the tools that were used to create the applications. We described the GPS system, application system Google Maps, web technologies, operating system Android, the development of applications for such systems and the development tool Android Studio. In the second part, we described the design and creation of our application for determining a geographic position of a remote mobile device. The application has the ability to broadcast the information of our current geographical position and the ability to receive the data of geographical position of some other mobile device. The application draws the received geographical position on the map. In the last part, we tested both application versions, compared them and described our observations.

Company management policy, that includes CRM (Customer Relationship Management) that is implemented with CRM computer system is rapidly growing in importance in Slovenia and worldwide. But just implementing CRM system is not enough if we want system that is well accepted and used daily. Integration with other systems in company is very important when implementing CRM system. Four types of integration are defined and they are usage, replication, synhronization and business process integration. Successful CRM system implementations include integration with e-mail systems and e-mail clients, ERP systems and other business software, document management systems, reporting systems and business inteligence systems, phone systems, web pages, social networks, external data sources and other systems. Integration should be done in phases and with great deal of planning and analysis. Only integrations that are identified as usefull for business should be done as every integration costs money and time to implement and maintain. Microsoft Dynamics CRM is a system that is well prepared for integration with other systems. Some integrations are out-of-the-box (Outlook, Dynamics ERP systems, SharePoint, phone systems), other integrations can be done with free or comercial 3rd party solutions (smarh phones, web site integrations, social networks) and there are couple of integrations tools and platforms that can connect to Dynamics CRM (BizTalk Server, Microsoft SQL Server Integration Services, Scribe Insight,...). Cloud computing is proving to be a difficulty when trying to integrate system. Data in the cloud is typically less available than on premise, access to data is also slower. Replication cloud data to local data stores solves some of these problems.