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Termodiagnostika - dotykové a bezdotykové měření teploty / Thermodiagnostics – contact and contact-free temperature measurementsMikula, Martin January 2014 (has links)
This thesis is concerned with thermodiagnostics in industrial practise, which is very important for the assessment of technical condition of object on the basis of temperature, in today's time. It includes summary of contact and contact-free methods and their principle, advantages and disadvantages for aplication in industrial practise. Because of thesis it was carried out measurement in company Daikin Device Czech republic with the use of contact thermometer and two available thermocameras for solving of topical tasks relating to production.
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Laboratorní ohřev vysokonapěťových kabelů / Laboratory heating of MV cablesVala, Martin January 2016 (has links)
This thesis deals with options of laboratory heating of high voltage cables. First part of the work is reserved for description of heat as physical phenomenon and quantities connected with the heat. Second part deals with options of temperature measurements of objects in practical use and third part of the work deals with options of cables heating regarding the measurements according the ČSN rules. Practical part of diploma thesis is focused on physical phenomenon description, being under way during measurement using selected methods in individual components and optimization of results for practical measurements.
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Vision Based Temperature Input in PID-Controlled 3D-Printer Applications : Viability of IR-thermometer thermography for use in 3D printer applications / Termografisk återkoppling för PID-regulatorer i 3D-skrivareEkelund, Vige, Hilleskog, Jakob January 2022 (has links)
In 3D-printers, accurate control of temperature is important and most often a thermistor is used to regulate it. However, while thermistors are cheap, they tend to be quite inaccurate at the wide temperature range of 3D-printers. And since they need to be in contact with the object they are measuring, they have to withstand the temperature that the object operates in. This work explores the possibility and viability of using a contactless solution for temperature feedback for the PID-regulator in 3D-printers instead of thermistors. Originally this work was supposed to use a thermal camera but because of unforeseen shipping problems, the thermal camera did not arrive in time, instead an IR-thermometer was used. The work was done by modifying the software of the 3D-printer to receive temperature from an external source, two available pins on the motherboard of the 3D printer were connected to a Raspberry Pi and with a custom made communication protocol and modified firmware, temperature data could be transferred between them. An IR-thermometer was mounted on the extruder of the 3D-printer, measuring the temperature of the heating block, it was also connected to the Raspberry Pi and its reported temperature was sent to the 3D-printer. To measure the performance of the different solutions, important data was logged and a visual inspection of printed parts were conducted. The results of the work showed that it was possible to replace the thermistor with a contactless IR-thermometer with a print quality that was on par with the original solution. It was also found that the IR-thermometer had a faster response-time to changes in temperature compared to the thermistor. The IR-thermometer should also have a wider object temperature-range than the thermistor but because this work was delimited to one specific thermoplastic material with one temperature-range, this was not tested. In conclusion the contactless solution had a result better than expected and is a promising proof of concept. The price of the contactless solution is magnitudes higher than that of the thermistor but with its promising accuracy and response time to changes in temperature it could be a viable solution for industrial applications.
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Implementation of Flash Analog-to-Digital Converters in Silicon-on-Insulator TechnologySäll, Erik January 2005 (has links)
High speed analog-to-digital converters (ADCs) used in, e.g., read channel and ultra wideband (UWB) applications are often based on a flash topology. The read channel applications is the intended application of this work, where a part of the work covers the design of two different types of 6-bit flash ADCs. Another field of application is UWB receivers. To optimize the performance of the whole system and derive the specifications for the sub-blocks of the system it is often desired to use a topdown design methodology. To facilitate the top-down design methodology the ADCs are modeled on behavioral level. The models are simulated in MATLAB®. The results are used to verify the functionality of the proposed circuit topologies and serve as a base to the circuit design phase. The first flash ADC has a conventional topology. It has a resistor net connected to a number of latched comparators, but its thermometer-tobinary encoder is based on 2-to-1 multiplexers buffered with inverters. This gives a compact encoder with a regular structure and short critical path. The main disadvantage is the code dependent timing difference between the encoder outputs introduced by this topology. The ADC was simulated on schematic level in Cadence® using the foundry provided transistor models. The design obtained a maximum sampling frequency of 1 GHz, an effective resolution bandwidth of 390 MHz, and a power consumption of 170 mW. The purpose of the second ADC is to demonstrate the concept of introducing dynamic element matching (DEM) into the reference net of a flash ADC. This design yields information about the performance improvements the DEM gives, and what the trade-offs are when introducing DEM. Behavioral level simulations indicate that the SFDR is improved by 11 dB when introducing DEM, but the settling time of the reference net with DEM will now limit the conversion speed of the converter. Further, the maximum input frequency is limited by the total resistance in the reference net, which gets increased in this topology. The total resistance is the total switch on-resistance plus the total resistance of the resistors. To increase the conversion speed and the maximum input frequency a new DEM topology is proposed in this work, which reduces the number of switches introduced into the reference net compared with earlier proposed DEM topologies. The transistor level simulations in Cadence® of the flash ADC with DEM indicates that the SFDR improves by 6 dB compared with when not using DEM, and is expected to improve more if more samples are used in the simulation. This was not possible in the current simulations due to the long simulation time. The improved SFDR is however traded for an increased chip area and a reduction of the maximum sampling frequency to 550 MHzfor this converter. The average power consumption is 92 mW. A goal of this work is to evaluate a 130 nm partially depleted silicon-oninsulator (SOI) complementary metal oxide semiconductor (CMOS) technology with respect to analog circuit implementation. The converters are therefore implemented in this technology. When writing this the ADCs are still being manufactured. Since the technology evaluation will be based on the measurement results the final results of the evaluation are not included in this thesis. The conclusions regarding the SOI CMOS technology are therefore based on a literature study of published scientific papers in the SOI area, information extracted during the design phase of the ADCs, and from the transistor level circuit simulations. These inputs indicate that to fully utilize the potential performance advantages of the SOI CMOS technology the partially depleted SOI CMOS technology should be exchanged for a fully depleted SOI CMOS technology. The manufacturing difficulties regarding the control of the thin-film thickness must however first be solved before the exchange can be done. / <p>Report code: LiU-Tek-Lic-2005:68.</p>
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Thermal Characterization of Heated Microcantilevers and a Study on Near-Field RadiationPark, Keunhan 05 April 2007 (has links)
Recently, remarkable advances have been made in the understanding of micro/nanoscale energy transport, opening new opportunities in various areas such as thermal management, data storage, and energy conversion. This dissertation focuses on thermally-sensed nanotopography using a heated silicon microcantilever and near-field thermophotovoltaic (TPV) energy conversion system.
A heated microcantilever is a functionalized atomic force microscope (AFM) cantilever that has a small resistive heater integrated at the free end. Besides its capability of increasing the heater temperature over 1,000 K, the resistance of a heated cantilever is a very sensitive function of temperature, suggesting that the heated cantilever can be used as a highly sensitive thermal metrology tool. The first part of the dissertation discusses the thermal characterization of the heated microcantilever for its usage as a thermal sensor in various conditions. Particularly, the use of heated cantilevers for tapping-mode topography imaging will be presented, along with the recent experimental results on the thermal interaction between the cantilever and substrate.
In the second part of the dissertation, the so-called near-field TPV device is introduced. This new type of energy conversion system utilizes the significant enhancement of radiative energy transport due to photon tunneling and surface polaritons. Investigation of surface and bulk polaritons in a multilayered structure reveals that radiative properties are significantly affected by polariton excitations. The dissertation then addresses the rigorous performance analysis of the near-field TPV system and a novel design of a near-field TPV device.
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Testovací metody pro hodnocení radiačních efektů v přesných analogových a signálově smíšených obvodech pro aplikace v kosmické elektronice / Test Methods for Evaluation of Radiation Effects in High Precision Analog and Mixed-Signal Devices for Space ApplicationsHofman, Jiří January 2019 (has links)
The traditional radiation testing of space electronics has been used for more than fifty years to support the radiation hardness assurance. Its typical goal is to ensure reliable operation of the spacecraft in the harsh environment of space. This PhD research looks into the radiation testing from a different perspective; the goal is to develop radiation testing methods that are focused not only on the reliability of the components but also on a continuous radiation-induced degradation of their performance. Such data are crucial for the understanding of the impact of radiation on the measurement uncertainty of data acquisition systems onboard research space missions.
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Drug Discovery Targeting Bacterial and Viral non-coding RNA: pH Modulation of RNAStability and RNA-RNA InteractionsHossain, Md Ismail 23 May 2022 (has links)
No description available.
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Soustava hodnocení tepelného stavu prostředí a analýza jejich nejistot měření / Evaluation System of Thermal Condition Environment and his Measurement Uncertainties AnalyzeKošíková, Jana January 2013 (has links)
The Ph.D. thesis deals with the evaluation of indoor thermal environment in which people are located. A great attention is paid to the thermal comfort. If a person in a given environment does not feel well, then makes mistakes. Thermal comfort is created many parameters that can be monitored and managed. These parameters include not only temperature but also other parameters such as the mean radiant temperature, operative temperature, humidity and air velocity and the draft. All these parameters can be measured. The standard ČSN EN ISO 7726 is written how and what the parameters are measured. Furthermore, this standard provides requirements for measuring equipment. There are many professional measuring devices. Unfortunately, these devices are very expensive. Therefore are within the project GACR 101/09/H050 - Research on energy- saving equipment to achieve the quality of the indoor environment at our faculty developed sensors for thermal comfort, which have showed comparable accuracy measurements as a professional , but it will be cheaper than professional. Knowledge of real parameters of the developed sensor thermal comfort environment is important, as with any other measurement devices, and also need to verified whether it has the required accuracy. In order to objectively sensors testing were developed two chambers - the testing and calibration chamber. The developed sensors were tested both in the open laboratory, and also in the test chamber. Then uncertainties measurement were calculated from the results of measurements This work deals with the evaluation of thermal comfort, the measurement of parameters of thermal environment, the evaluating the results of measurements and determining the measurement uncertainty of the sensors. In this thesis, based on these results, were recommended suitable sensors for measuring various parameters environment.
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