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Energy Intensity Reduction of a Professional Laundry Care Process
Bobák, Petr ; Klemeš,, Jiří (referee) ; Noskievič, Pavel (referee) ; Stehlík, Petr (advisor)
Doctoral thesis deals with professional laundry care process and reduction of energy intensity and use of other operational commodities used in the process. Professional laundry care process is a specific energy intensive process; its purpose is to re-establish original properties of the now dirty laundry so that it may fulfil its functions again. This is basically a recycling and regeneration process comprising many sub-operations. Key operation is washing of the laundry in a washing bath, which removes impurities from the laundry. This thesis describes the most common technology of impurities removal, which is washing in a hot washing bath in cooperation with mechanical work and detergents. However, all of the described procedures may also be applied on alternative technologies, such as ozone washing, washing with low-temperature enzymes and ultrasound. Water is applied in all these technologies as a soaking agent. Water must have appropriate properties and must be removed from the laundry after the washing process in subsequent operations (drying, ironing, and pressing). Theoretical introduction of the thesis describes professional laundry care process in detail, and continues with mathematical modelling of the process and its main sub-operations (washing, drying) using mass and heat balance, and data acquisition and their application in research and development. Thesis further describes design of information system on the basis of relational database controlled by web application. This system enables to organize data and information from various sources – measured experimental data, data concerning measurement devices, operational records of machines, etc. Thesis further proposes how to evaluate and reduce energy intensity of a process. Descriptions are validated by examples and case studies. Key section of the thesis is a chapter describing experimental infrastructure. This infrastructure integrates several instalments of laundry equipment and is a fully functional operation of industrial laundry facility with 500kg/shift capacity, which serves as a model of energy intensive process. Sophisticated infrastructure and data acquisition system allows measuring wide spectrum of physical entities and examining factors influencing energy intensity of processes, and relationships between these factors as well as effectiveness of various savings measures in real life facilities.
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Visualization of Network Security Events
Stehlík, Petr ; Kováčik, Michal (referee) ; Krobot, Pavel (advisor)
This thesis focuses on visualization of network security events via modern web technologies. Multiple technologies for creating modern web application supporting visualising large volume of security events were studied. The application was designed for NEMEA system which thanks to this thesis acquired graphical user interface allowing big data visual analysis. Visualized events allow drill-down analysis. The application operates on security events stored in IDEA format which is used among other network security services and the application is therefore transferrable to them. NEMEA Dashboard has been tested on the target group of network administrators using acceptance tests.
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Regional waste-to-energy systems
Krňávek, Martin ; Jelemenský, Karol (referee) ; Jegla, Zdeněk (referee) ; Stehlík, Petr (advisor)
The doctoral thesis deals with regional energy utilization of municipal waste, sewage sludge and hazardous medical waste. In the first part of the thesis, the conditions under which waste-to-energy plants can be effectively integrated into regional energy supply system are assessed. In this introductory part, the current energy situation, legislation as well as waste in the Czech Republic are analyzed. Furthermore, the possibilities of integration at different levels in relation to the WtE plant and the complex waste management concept are described. In the next part of the thesis, the possibilities of long-term and short-term energy accumulation for the WtE plant are assessed. From the point of view of short-term energy accumulation, warm water, hot water and steam accumulators are assessed and from the point of view of long-term energy accumulation, the storage of plastic and bulky waste and sewage sludge is analyzed. The created techno-economic models of modern technologies for energy utilization of municipal waste, sewage sludge and hazardous medical waste are described in the main part of the thesis. In the last part of the thesis, the proposed techno-economic models are applied to the conditions of the specific region, and the effectiveness of tailor-made solutions respecting the 3E (environmental protection, energy situation and economic aspects) is demonstrated on this example.
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Simulation tool for gas microturbine integration into industrial operations
Konečná, Eva ; Stehlík, Petr (referee) ; Ovčačík,, Filip (referee) ; Máša, Vítězslav (advisor)
Current challenging energy situation gives rise to the need for highly efficient use of primary energy sources. Gas microturbines are a potential solution to this situation as they represent a progressive source of combined heat and power production. Gas turbines work with electric efficiency around 30 % and another 50 % is hidden in hot flue gas. Leveraging this waste heat is essential for achieving high overal efficiency of production and minimizing the use of primary energy. This thesis introduces a methodology for integration of gas microturbines into industrial operation. This methodology served as a basis for creating a software tool for selecting an optimal gas microturbine and seting up an efficient use of the waste heat from the produced flue gas, specifically direct drying, technological heating of process streams, preparation of warm utility water, and heat accumulation. It also includes technical-economic evaluation of the investment. The methodology is represented by an unique software tool which evaluates various alternatives of a gas microturbine integration into a mid-sized industrial laundry, and recommends the most favourable option. The tool was build using programming language Python in combination with MS Excel to offer great ease of use without a need for any specialized software. The biggest advantage, however, is its universality which allows adapting this software for other industrial processes. It is sufficient for the user to only have a standard operational knowledge of the target process. A laundry operation was selected for this case study, and data from several industrial laundries in Czech republic was collected. Its analysis revealed that the ratio of required electrical and heat energy is an important criterium when selecting a gas microturbine as the main power source. Specifically for older laundry operations, it is necessary to firstly undergo an energy optimization before selecting a suitable power source. If integrated correctly, it is possible to achieve overal efficiency of the gas microturbine of up to 90 % and an acceptable payback period of the investment. A suitable target process for integrating the gas microturbine is one that leverages the gas microturbine’s biggest advantage – production of hot and clean flue gas. It is necessary to look for those processes where a maximum of this flue gas can be used directly without a need for any other costly devices for heat transfer. Drying in laundries certainly represents such a process. The proposed software is an easy, quick, and most importantly universal tool for evaluating suitability of a gas microturbine based on common operational knowledge of the respective process.
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Impact of the Openness of Public Tenders and Traceability of the Beneficial Owner on the Price of Public Procurement
Stehlík, Petr ; Ochrana, František (advisor) ; Nemec, Juraj (referee) ; Pavel, Jan (referee)
The aim of this thesis is to analyse factors that contributes to public procurement overpricing in the Czech Republic. The paper combines use of quantitative and qualitative research methods. Existence of competition effect is proved, thus increase of competitors in selection procedure causes that final price decreases. Non-transparent suppliers in terms of traceability of beneficial owner is detected as next factor that contributes to overpricing. Also some types of contracts are showed as more problematic than others. Results of qualitative part of the research reveal other causes of overpricing, such as corruption, weak institutional environment or behaviour of public authorities. Public policy recommendations are presented at the end of the paper in order to improve current state of affairs.
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A Social Enterprise Law As Means To Combat Social Exclusion
Kolář, Šimon ; Potůček, Martin (advisor) ; Stehlík, Petr (referee)
Thesis "Analysis of legislative and social conditions of supporting social entepreneurship in the Czech Republic" delves into the issue of social entepreneurship in the Czech Republic. The main aim of the thesis is to analyze both social and legislative conditions that actors use to battle social exclusion through social entepreneurship in the Czech Republic. To achieve this, a case study needed to be exercised; interviews with actors from both employers and employees of these businesses were carried out. Moreover, issues that these businesses have to deal with were identified and are described as well as benefits for the target population. Furthermore, conditions that have to be met in order to receive funding from the ESF are described. The way these conditions are designed and ultimately evaluated is discussed in detail. Using actor centered institutionalism, actors that take part in discussions regarding the legislation, which is currently being prepared, are identified and described. Interactions between these actors are discussed and, additionally, recommendations for the further development of social entepreneurship in the Czech Republic are being put forward.
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EFFECTIVE UTILIZATION OF MUNICIPAL SOLID WASTE IN HEAT AND POWER SYSTEMS
Putna, Ondřej ; Klemeš, Jiří (referee) ; Ucekaj, Vladimír (referee) ; Stehlík, Petr (advisor)
The dissertation thesis is focused on the issue of energy recovery of waste. It contributes to optimization models developed in the author's workplace in the long term, which serve to simulate material flows in waste management and to search for an optimal waste management strategy. The main objective is to assess the potential for the use of heat produced in waste-to-energy plants as a key factor for the economy of these facilities. The thesis therefore represents an activity on the border of the fields of waste management and heating. Partial mathematical models were developed within the scope, for which it was necessary to collect input data, especially in relation with district heating networks. These models were then used in a comprehensive optimization model describing the integration of waste-to-energy plants with other heat sources. This main model was extended to include the environmental aspect.
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Complex Waste Collection Models
Nevrlý, Vlastimír ; Šenkeřík, Roman (referee) ; Procházka,, Vít (referee) ; Stehlík, Petr (advisor)
The subject of this doctoral thesis is the solution of logistics systems in the context of waste management. The work begins with an extensive research in the field of modelling various situations from the waste transportation chain. There are presented multiple types of practical tasks in the area of operation research applicable to waste management. Their possibilities of extension and modification are analysed for use by investors, technical services or waste collection service providers. An essential part of the work is the identification of critical parameters in the waste collection at the level of municipalities and micro-regions. Based on practical requirements, challenges related to the improvement of decision-making and planning systems are defined. The available techniques proved to be insufficient for practical problems. For the area of changes and designs of collection systems (design and modification of routes, choice of the vehicle fleet, collection plan, etc.) there are no procedures that would include a whole range of operating conditions and parameters. The boundary conditions of the task affecting fundamental requirements are highly variable. The thesis presents a comprehensive approach, which is divided into several phases. The preparation and analysis of input data focused mainly on the creation of transport infrastructure, allocation of waste collection containers and their pairing to the network, which also reduces the size of the task. Furthermore, a procedure for compliance with the rules of the road was designed using a penalty function, and an algorithm for defining imaginary edges was implemented, which will allow distinguishing the frequency of collection on selected network segments. To reduce the size of the task, a segment clustering algorithm was also designed, which will enable the calculation of the collection even for larger areas. Input parameters related to operating time and fullness of collection containers are elaborated in greater detail, as they most influence the results of the task. A great benefit is also the algorithm generating the initialization solution from historical routes. As part of the related publishing activities, environmental criteria were defined to evaluate global and local impacts of waste transportation and treatment. The outputs of the thesis are used primarily for the analysis of collection systems, to support the deployment of waste containers, planning collection routes, time schedules and dimensioning the size of the vehicle fleet. The proposed algorithms were tested in several case studies, which proved the broad applicability of a comprehensive tool in the field of waste logistics. Although the thesis is focused on modelling the collection of municipal waste, the usability of the implemented procedures is possible in other areas of waste management or other sectors.
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The FITkit3 Tester
Stehlík, Petr ; Strnadel, Josef (referee) ; Bidlo, Michal (advisor)
This work solves the problem of testing a certain set of ARM Kinetis Cortex-M4 \newline (MK60DN512ZVMD10) microcontroller modules on the FITkit3 learning platform (also known as Minerva). Specifically, it deals with the design of test firmware in the C programming language for automated testing, the design of a hardware module for testing platform input/output interfaces using the MCP23S17 integrated circuit and the design of a software with text-based user interface in Python3 for the testing control from a PC. The selected test set of modules are Periodic interrupt timers (PIT), Low-power timer (LPTMR) and Real time clock (RTC), further modules for serial data transmission via UART and SPI interfaces, speaker and GPIO ports. The created solution provides a comprehensive tool for analysing the functionality of frequently used modules on FITkit3, which automates the analysis process almost completely. The main benefit of this work is the facilitation of testing and a rapid detection of errors in a large number of kits.
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Analysis of Operational Data and Detection od Anomalies during Supercomputer Job Execution
Stehlík, Petr ; Nikl, Vojtěch (referee) ; Jaroš, Jiří (advisor)
V posledních letech jsou superpočítače stále větší a složitější, s čímž souvisí problém využití plného potenciálu systému. Tento problém se umocňuje díky nedostatku nástrojů pro monitorování, které jsou specificky přizpůsobeny uživatelům těchto systémů. Cílem práce je vytvořit nástroj, nazvaný Examon Web, pro analýzu a vizualizaci provozních dat superpočítače a provést nad těmito daty hloubkovou analýzu pomocí neurálních sítí. Ty určí, zda daná úloha běžela korektně, či vykazovala známky podezřelého a nežádoucího chování jako je nezarovnaný přístup do operační paměti nebo např. nízké využití alokovaých zdrojů. O těchto faktech je uživatel informován pomocí GUI. Examon Web je postavený na frameworku Examon, který sbírá a procesuje metrická data ze superpočítače a následně je ukládá do databáze KairosDB. Implementace zahrnuje disciplíny od návrhu a implementace GUI, přes datovou analýzu, těžení dat a neurální sítě až po implementaci rozhraní na serverové straně. Examon Web je zaměřen zejména na uživatele, ale může být také využíván administrátory. GUI je vytvořeno ve frameworku Angular s knihovnami Dygraphs a Bootstrap. Uživatel díky tomu může analyzovat časové řady různých metrik své úlohy a stejně jako administrátor se může informovat o současném stavu superpočítače. Tento stav je zobrazen jako několik globálně agregovaných metrik v posledních 30 minutách nebo jako 3D model (či 2D model) superpočítače, který získává data ze samotných uzlů pomocí protokolu MQTT. Pro kontinuální získávání dat bylo využito rozhraní WebSocket s vlastním mechanismem přihlašování a odhlašování konkretních metrik zobrazovaných v modelu. Při analýze spuštěné úlohy má uživatel dostupné tři různé pohledy na danou úlohu. První nabízí celkový přehled o úloze a informuje o využitých zdrojích, času běhu a vytížení části superpočítače, kterou úloha využila společně s informací z neurálních sítí o podezřelosti úlohy. Další dva pohledy zobrazují metriky z výkonnostiního energetického hlediska. Pro naučení neurálních sítí bylo potřeba vytvořit novou datovou sadu ze superpočítače Galileo. Tato sada obsahuje přes 1100 úloh monitorovaných na tomto superpočítači z čehož 500 úloh bylo ručně anotováno a následně použito pro trénování sítí. Neurální sítě využívají model back-propagation, vhodný pro anotování časových sérií fixní délky. Celkem bylo vytvořeno 12 sítí pro metriky zahrnující vytížení procesoru, paměti a dalších části a např. také podíl celkového času procesoru v úsporném režimu C6. Tyto sítě jsou na sobě nezávislé a po experimentech jejich finální konfigurace 80-20-4-3-1 (80 vstupních až 1 výstupní neuron) podávaly nejlepší výsledky. Poslední síť (v konfiguraci 12-4-3-1) anotovala výsledky předešlých sítí. Celková úspěšnost systému klasifikace do 2 tříd je 84 %, což je na použitý model velmi dobré. Výstupem této práce jsou dva produkty. Prvním je uživatelské rozhraní a jeho serverová část Examon Web, která jakožto rozšiřující vrstva systému Examon pomůže s rozšířením daného systému mezi další uživatele či přímo další superpočítačová centra. Druhým výstupem je částečně anotovaná datová sada, která může pomoci dalším lidem v jejich výzkumu a je výsledkem spolupráce VUT, UNIBO a CINECA. Oba výstupy budou zveřejněny s otevřenými zdrojovými kódy. Examon Web byl prezentován na konferenci 1st Users' Conference v Ostravě pořádanou IT4Innovations. Další rozšíření práce může být anotace datové sady a také rozšíření Examon Web o rozhodovací stromy, které určí přesný důvod špatného chování dané úlohy.
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