Temperature regulator with ESP8266

Bakalářská práce se zabývá vývojem chytrého zásuvkového termostatu, který je schopen komunikovat s uživatelem a dalšími aplikacemi pomocí wifi rozhraní v pásmu 2,4 GHz. Související problematikou je elektrické měření teploty. Další oblastí, na kterou se práce zaměřuje, jsou IoT online cloudy, které se v dnešní době používají pro logování a vizualizaci naměřených dat. V praktické části je podrobně rozebrán vývoj DPS od návrhu až po jednotlivé vývojové verze. Neodmyslitelnou součástí je také firmware a ověření funkčnosti regulace.The bachelor thesis mainly focuses on a development of a smart socket thermostat able to communicate with a user and other applications via Wi-Fi interface in the 2.4 GHz band. Subsequent centers of attention are electrical temperature measurement and analysis of IoT clouds, currently used for logging and visualization of gauged data. Essential part of the work is the detailed depiction of PCBs development from their design to the particular stages of progress. The last but not least are the firmware measures and the regulation functionality verification.

ANALYSIS OF THE INFLUENCE OF TRANSDUCER FREQUENCY ON THE ULTRASONIC MEASUREMENT OF CONCRETE HOMOGENEITY

The paper analyses the influence of transducer frequency on the determination of concrete homogeneity using the ultrasonic pulse velocity test. Transit time measurements were made on a 590×590mm concrete slab, with 110mm in thickness, in a raster of 5×5 points, which means the slab was tested in 25 places. The tests were made using a Pundit PL-200 ultrasonic tester using transducers set at 54, 82, and 150 kHz. Two types of measurements were performed – spot measurements of the ultrasonic pulse transit time at each point and full area scanning. The paper is concluded by an evaluation of the concrete slab’s homogeneity measured by different transducers and techniques in addition to a statistical analysis of how the results are affected by the transducer frequency

Concrete: Limit States and Sustainability

The structural design of concrete structures has to result in qualities ensuring ordinary structural safety and serviceability, together with durability. Recently, it has become necessary to pursue sustainability as well, and rather newly the issue of resilience has also appeared. It is now apparent that the effects of mechanical load, environmental load and even social coherence need to be reflected and included in the formulation of limit states. This is a complex matter involving the factors of time, service life, degradation effects, modelling, probability analyses, limit states, costs and other phenomena. It has not yet been completely understood, albeit several notions in this context are contained in different codes and regulations, e.g. EN 1990, EN 1992, ISO 13823:2008, ISO 16204:2012, fib MC2010 and fib MC2020 (currently under preparation by the fib committees). According to fib Model Code 2010, the design method most commonly used for concrete structures today is performance-based. Sustainable target value design can be briefly expressed as the comparison of sustainable capacity vs. sustainable impacts. This requires the formulation of a new class of limit states – apart from those of the engineering (or structural) type, also sustainability limit states now need to be specified. The presented contribution briefly mentions traditional and durability limit states, discussing their variants and context, and then concentrates specifically on the formulation of limit states for concrete sustainability at material level. It also presents some examples which apply a full probabilistic approach

Methodology for the quantification of concrete sustainability

LCA is a method that evaluates the life cycle of a structure from the point of view of its impact on the environment. Consideration is given also to energy and raw material costs, as well as to environmental impact throughout the life cycle – e.g. due to emissions. The paper focuses on the quantification of sustainability connected with the use of various types of concrete with regard to their resistance to degradation. Sustainability coefficients are determined using information regarding service life and “eco-costs”. The aim is to propose a suitable methodology which can simplify decision-making in the design and choice of concrete mixes from a wider perspective, i.e. not only with regard to load-bearing capacity or durability

Analysis of Acoustic Emission Signals Recorded during Freeze-Thaw Cycling of Concrete

This manuscript deals with a complex analysis of acoustic emission signals that were recorded during freeze-thaw cycles in test specimens produced from air-entrained concrete. An assessment of the resistance of concrete to the effects of freezing and thawing was conducted on the basis of a signal analysis. Since the experiment simulated testing of concrete in a structure, a concrete block with the height of 2.4 m and width of 1.8 m was produced to represent a real structure. When the age of the concrete was two months, samples were obtained from the block by core drilling and were subsequently used to produce test specimens. Testing of freeze-thaw resistance of concrete employed both destructive and non-destructive methods including the measurement of acoustic emission, which took place directly during the freeze-thaw cycles. The recorded acoustic emission signals were then meticulously analysed. The aim of the conducted experiments was to verify whether measurement using the acoustic emission method during Freeze-thaw (F-T) cycles are more sensitive to the degree of damage of concrete than the more commonly employed construction testing methods. The results clearly demonstrate that the acoustic emission method can reveal changes (e.g., minor cracks) in the internal structure of concrete, unlike other commonly used methods. The analysis of the acoustic emission signals using a fast Fourier transform revealed a significant shift of the dominant frequency towards lower values when the concrete was subjected to freeze-thaw cycling

Ultrasonic NDT determination of initial and final setting time of cement paste

There are several methods for determination of the setting and early hardening in the cementitious composites. The most common method is using the Vicat apparatus. The major disadvantage of this method is that it is invasive and therefore the measurement results exhibit high variability. The paper deals with the continual monitoring of the process of setting and early hardening of a cement paste using the ultrasonic measurement. The innovative method of using the ultrasonic NDT method for determination of the setting times of cement paste is presented in the paper

Effect of De-Icing Chemicals on Concrete Scaling: The Role of Storage Water

This paper deals with the effect of the character of the water used for the water storage of concrete test specimens on the results of tests for resistance to de-icing chemicals. Two experiments were conducted to investigate the effect of the content of free CO2 in water and leaching of calcium hydroxide from concrete on the test results. In the first experiment, the resistance of mortars to water and de-icing chemicals was investigated. It was found that the character of the water storage, i.e., fresh water vs. previously used water, can significantly affect the test results. The second experiment focused on investigating the effect of the content of free CO2 in water on the test results. It was found that the content of free CO2 in the water can statistically significantly influence the test results. In conclusion, the paper shows that the character of the water used for water storage of concrete test specimens and the content of free CO2 in water are essential factors that can significantly affect the results of concrete resistance tests to de-icing chemicals. Further research is needed to understand these influences and their potential use to improve the resistance of concrete

Effect of dexamethasone in patients with ARDS and COVID-19 (REMED trial)—study protocol for a prospective, multi-centre, open-label, parallel-group, randomized controlled trial

BACKGROUND: Since December 2019, SARS-CoV-2 virus has infected millions of people worldwide. In patients with COVID-19 pneumonia in need of oxygen therapy or mechanical ventilation, dexamethasone 6 mg per day is currently recommended. However, the dose of 6 mg of dexamethasone is currently being reappraised and may miss important therapeutic potential or may prevent potential deleterious effects of higher doses of corticosteroids. METHODS: REMED is a prospective, open-label, randomised controlled trial testing the superiority of dexamethasone 20 mg (dexamethasone 20 mg on days 1-5, followed by dexamethasone 10 mg on days 6-10) vs 6 mg administered once daily intravenously for 10 days in adult patients with moderate or severe ARDS due to confirmed COVID-19. Three hundred participants will be enrolled and followed up for 360 days after randomization. Patients will be randomised in a 1:1 ratio into one of the two treatment arms. The following stratification factors will be applied: age, Charlson Comorbidity Index, CRP levels and trial centre. The primary endpoint is the number of ventilator-free days (VFDs) at 28 days after randomisation. The secondary endpoints are mortality from any cause at 60 days after randomisation; dynamics of the inflammatory marker, change in WHO Clinical Progression Scale at day 14; and adverse events related to corticosteroids and independence at 90 days after randomisation assessed by the Barthel Index. The long-term outcomes of this study are to assess long-term consequences on mortality and quality of life at 180 and 360 days. The study will be conducted in the intensive care units (ICUs) of ten university hospitals in the Czech Republic. DISCUSSION: We aim to compare two different doses of dexamethasone in patients with moderate to severe ARDS undergoing mechanical ventilation regarding efficacy and safety. TRIAL REGISTRATION: EudraCT No. 2020-005887-70. ClinicalTrials.gov NCT04663555. Registered on December 11, 2020

Simulation of Entities Collective Behavior in Virtual World

Theme of this work is to evaluate and compare aviable paradigms for entity control in virtual worlds, and to implement one of these paradigms in application. Dynamic finite state machine upgraded using genetic algorithms has been chosen. This paradigm should make agent's behavior better and adapt agent to required state: i.e. make agent harvest resources in virtual world. Output of this work is application for running evolution and application for 3D view of agent's behavior