Potential of biomass resources in CZE and costs of its energy utilisation - I

Cílem bakalářské práce ,,Potenciál biomasy v ČR a náklady na její energetické využití,, je zhodnotit finanční stránku energetického využití biomasy a shrnout faktory, které ovlivňují cenu biomasy na trhu České repuliky. Práce se zaměřuje na dřevní štěpku. V úvodu se práce zabývá základním rozdělením biomasy a jejím energetickým využitím. Další kapitola je věnována dřevní štěpce a její výrobě a vlastnostem. Druhá část práce se věnuje výskytu dřevařských podniků v ČR a zhodnocení ceny štěpky.This bachelor thesis ,,Potential of biomass resources in CZE and costs of its energy utilization,, evaluates financial part of energetic use of biomass and summarizes factors affecting the price of biomass on Czech market. The work is focused on wood chips. In the introduction there is an overview of basic division of biomass and utilization as an energy source. Next chapter is about wood chips, their production and properties. Second part of the thesis describes the occurrence of lumber companies in Czech Republic and assessment of wood chips price.

Unit for utilization of contaminated biomass for energy production

Cílem práce je vytvoření předběžných návrhových výpočtů pro určení rozměrů, hmotnosti a tlakové ztráty jednotlivých uzlů čištění spalin kontaminované biomasy. První část práce je věnována definici biomasy jako paliva, legislativnímu určení množství povolených emisí a jejich popisu. Dále jsou v práci představeny zařízení na čištění spalin a jejich stručný popis. Praktická část se věnuje tvarovým návrhům, určení základních rozměrů několika typů kontaktorů doplněné o výpočty hmotností a tlakových ztrát těchto aparátů. V poslední části jsou jednotlivé varianty řešení porovnávány mezi sebou.The purpose of the thesis is to create preliminary design calculations to determine dimensions, weights and pressure losses of individual contaminated biomass combustion gas treatment nodes. The first part of the thesis deals with the definition of biomass as a fuel, legislative determination of allowed emissions and their description. Then the systems for combustion gas treatments are discussed given their brief description. The practical part focuses on shape designs, determining base dimensions of each type. Weights and pressure losses of individual versions are computed too. In the last part the individual versions are solved with real values and compared to each other.

Determining the plasticity of mannitolum

The visco-elastic characteristics and knowledge of them are the important factors that influence pressability of materials. These characteristics differ for every material and it is possible to determine them by variety of methods. In our thesis (chapter Experiments) we evaluated the relationship "force - travel" and determined elasticity and plasticity of materials. The test of relaxation of tense is another way to determine plasticity of materials. The results are parameters of FminA, FminB, FPL and parameters of single-parametric equation that describes decrease of preassure in a tablet during the relaxation period. These parameters and their evaluation are the goal of this thesis. We determined the Young's modulus of elasticity from the tablet dilatation measure restults. The value of Young's modulus of elasticity for mannitol is 413,36 MPa. The value of total plasticity Pc is 91,34177 MPa.s. Generally: increasing value of total plasticity determines increase of tablet material pressability

Determining the plasticity of mannitolum

The visco-elastic characteristics and knowledge of them are the important factors that influence pressability of materials. These characteristics differ for every material and it is possible to determine them by variety of methods. In our thesis (chapter Experiments) we evaluated the relationship "force - travel" and determined elasticity and plasticity of materials. The test of relaxation of tense is another way to determine plasticity of materials. The results are parameters of FminA, FminB, FPL and parameters of single-parametric equation that describes decrease of preassure in a tablet during the relaxation period. These parameters and their evaluation are the goal of this thesis. We determined the Young's modulus of elasticity from the tablet dilatation measure restults. The value of Young's modulus of elasticity for mannitol is 413,36 MPa. The value of total plasticity Pc is 91,34177 MPa.s. Generally: increasing value of total plasticity determines increase of tablet material pressability

Identification of thermal model of power module using expectation-maximization algorithm

Prediction of junction temperatures in power semiconductor modules is essential to improve reliability of the device and prevent module failures due to thermal stress. Lumped parameter network is a popular approach for temperature modeling. Calibration of the thermal model is based on thermal measurements of the junction temperatures that are difficult to obtain. We aim to combine the knowledge of internal model structure and as little measurements as possible. Specifically, we use a state space thermal model with structure determined by the module layout, and propose to use the Expectation-Maximization algorithm from that can utilize data from different incomplete experiments. The identification procedure is introduced in detail in this paper and the applicability of the proposed approach is demonstrated on simulated and experimental data

Identification of Thermal Model Parameters Using Deep Learning Techniques

Identification of thermal model parameters using multi-step prediction is proposed. Even in the case of a linear model, the multi-step prediction is a non-linear complex function, hence we use techniques of deep learning for its identification. Specifically, we use stochastic gradient descent optimization with importance sampling of mini-batches. The importance function is designed to match the character of thermal experiments in which the step change is less frequent than steady-state operation. The proposed method is demonstrated on the identification of an IGBT module SK 20 DGDL 065 ET. The maximum error of the model identified by the multi-step approach is almost two times smaller than that of the model identified by the least squares

Identification of Thermal Model Parameters Using Deep Learning Techniques

Identification of thermal model parameters using multi-step prediction is proposed. Even in the case of a linear model, the multi-step prediction is a non-linear complex function, hence we use techniques of deep learning for its identification. Specifically, we use stochastic gradient descent optimization with importance sampling of mini-batches. The importance function is designed to match the character of thermal experiments in which the step change is less frequent than steady-state operation. The proposed method is demonstrated on the identification of an IGBT module SK 20 DGDL 065 ET. The maximum error of the model identified by the multi-step approach is almost two times smaller than that of the model identified by the least squares