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This diploma thesis deals with the concentration of dust particles during harvesting of forage, namely hay, straw and fed forage. The measurements were always carried out on another land in the Vysočina Region. DUST TRAK II 8530 instrument was used to measure dust concentration. Each measurement was performed for ten minutes.

The work is devoted to the influence of dust particles on the operation of rotating machines with sliding contact. In the work are described and characterized dust particles from environment of selected machines. Their influence on sliding contact and influence on the insulation system of these machines is investigated.

Filler words and expressions in Portuguese (Abstract) The aim of this study is to describe the morphological, syntactic, semantic and pragmatic aspects of the filler words and expressions (discourse markers) in Portuguese. For that purpose, a corpus of more than 3000 occurences of these expressions was assembled. It is composed of Portuguese and Brazilian mostly spoken texts belonging to different genres. The approach taken in this work is based on textual-interactive grammar, whose vision of the text is based on the social-communicative perspective, i.e. it takes not only the cognitive- informational part of the utterances, but also their interactional part in consideration. This study describes Portuguese as one language. The differences between the Brazilian and the European variety are taken in consideration only when it is necessary to treat them separately. This work can be divided into two parts. History of the filler expressions, different approaches to this issue, processes of grammaticalization and pragmaticalization and prototypical conception of the class of discourse markers (whose brief characterization as well) are discussed in the first part. A more detailed analysis of the morphological, syntactic, semantic and pragmatic aspects of the discourse markers are discussed in the second part. The...

The diesel engine emissions belong nowadays to most monitored issues, especially when it deals with the fine particles and their elimination from the exhaust fumes using the particle filters. This thesis deals with the reliability and durability of particle filters measured in the emissions of exhaust fumes. The thesis describes the different types of particle filters and methods of their regeneration. The individual measuring device has been described in order to comprehend all the processes that take place during the measurement. The author used mathematic methods to evaluate the income variables. In its practical part the thesis has evaluated – by using the statistical methods – the reliance of measured quantities in the exhaust fumes.

The diploma thesis deals with the problematics of engine oils degradation in a garden machinery. In the theoretical part, there is a description of the basic functions and properties of engine oils, their production, composition and also used standard classifications. The practical part is devoted to evaluation of the degradation of five selected engine oils. There are described the oils, the selected garden machinery (five machines with a four-stroke spark-ignition engine) and also the sampling methodology and measuring devices. Two samples of oil were taken from each machine – a partially used and a used engine oil, which were compared with a new oil of the same specification and designation. For all samples, their dynamic viscosity (at 40 °C), density and amount of selected metal wear particles were measured. In the final chapter, the measured parameters are processed into a tables and graphs, and the results are discussed.

This Master's thesis focuses on the problematics of the diesel engine oil in the combine harvesters degradation. The first part focuses on the manufacturing process of the en-gine oils, on their structure, on the description of their properties and on their division into individual classifications. Types of the lubrication systems and the diagnostics of the engine oils are described next. Seven samples of oil were monitored, three of them were samples of used engine oil from the combine harvesters Claas, where the engine oil with viscosity grade 10W-40 was used. Next two samples were from used oil from the combine harvesters Case IH, where was the engine oil with viscosity grade 15W-40. Two samples of new oil of each kind were taken for the comparison of the engine oil degradation. Their physical and mechanical properties were compared afterwards. The results obtained are interpreted both numerically and graphically. In the conclusion, the evaluation and the results obtained are summarized.

This thesis deals with description of engine oils in diesel combustion engine of combine harvester. First part contains basic properties of engine oils and their production. Other chapters include classification of oil and also the issue of abrasion particles in the engine. Practical part contain summary of engine oil from combine harvester Case IH AFX 9120. For comparison was sampled new oil. Other samples were taken during machine operation every 50 Eh until of the service interval of 300 Eh. The thesis also describes the methodology of measurement process measuring device for evaluation of the content abrasion particles, density, dynamic and kinematic viscosity and skid tension. The results are processed into a graph and from the results obtained was determined actual state of degradation of engine oil.

B. Štěpánková K funkci výrazů částicové povahy ve výstavbě textu... ABSTRACT This dissertation is devoted to a specific type of particle unit which we refer to as the actualizer. Actualizers are differentiated from other particles primarily due to a combination of the following properties: the ability to imply a presupposition and the ability to actualize or emphasize a nearby expression. They play an important role in the topic-focus articulation of a sentence by drawing attention to elements with a greater degree of communicative dynamism, not only in focus or contrastive topic, but also in other parts of the sentence. Unlike previous studies which have concentrated mainly on prototypical representatives of these units, this dissertation tries to capture the greatest possible number of actualizers. At the same time, it aims to describe their semantic characteristics, and based on this, it attempts to categorize actualizers into three semantic groups. From this perspective, we can distinguish between restrictive, inclusive, and temporally emphasizing actualizers. These groups can be further divided according to their specific features. The dissertation also analyzes the possible positioning of the actualizers in various places in a sentence and investigates which expressions can occur in the surroundings...

Children are a susceptible group to environment pollution. The environment, in which they spend the most time, is the home, the second is the school. Therefore, the indoor environment of a school affects their health, wellbeing and even school results. The present work investigated concentrations of air pollutant, aerosol particles, in the specialized classrooms (computer lab, arts and biology/chemistry) in an elementary school, Prague. Direct reading instruments measuring mass concentration of four aerosol fractions and number concentration of submicrometer particles were used for measurement. Measurements were carried out for four weekdays in each month from November 2011 to July 2012. It was found that mass concentrations of submicrometer particles were dependent on outdoor concentrations, in contrast to supermicrometer particles which were affected mainly by physical activities of students and outdoor concentration had a minimal effect. Increased number concentrations of submicrometer particles were observed only during children presence, concentrations were probably induced by student activities during lessons. Seasons also influenced mass concentrations, when the highest indoor and outdoor concentrations were recorded in a spring/autumn season. Classroom location affected submicrometer...