The dissertation thesis is used as a methodology for prediction of selected parameters of rotational kinematic pairs of machine tools. The motivation for its writing has been continually increasing requirements for parameters (performance, accuracy, static and dynamic stiffness) of machine tools. The methodology takes into account the availability of suitable measuring devices and description of the design of rotary kinematic pairs. It will be useable for predicting the behavior of rotational kinematic pairs, even at the design stage by applying results to the machine design. The work is processed so that first is used a system approach to suggest methodology for prediction of the behavior of rotary kinematic pair in CNC machine tools, planning measurement strategy and verifying the results, including applications for specific kinematic chain of the selected machine. Based on this system approach and the resulting methodology, the measurement of the rotary kinematic pair was performed. The results of the system approach and measurement are generalized in the form of recommendations for designers of machining centers, allowing to increase the accuracy of the rotational kinematic pair.

This diploma thesis follows visualization of snow formations, which are called penitentes. This work includes also collecting the data needed to derive the optical properties of the penitentes material. Which are different phases between snow and ice. For visualization method is used Progressive Transient Photon Beams, that this work implements with the help of SmallUbpb.

The subject of this thesis is a design of the volumetric infusion pumping unit specifically used for a human medicine purposes. The pumping unit is constructed by the linear peristaltic pump. The document focuses on mechanical design and disposition of particular components of unit and placement of electronic sensors and contacts. The thesis is elaborated as a part of infusion pump development project for a limited company.

This diplomathesis work is dealing with a concept of volumetric calibration of vessels using the volumetric method. The analysis considers current regulations together with influence of uncertainties in measurements. The principal part of the thesis is analysis of metrological uncertainties resulting from application of various volumetric methods during the calibration process. A practical outcome from this research is development of metrological process for calibration of vessels that could be used by the accredited laboratories.

Bc. Roman Kaňa Working accuracy machine MCV 754 Main aim of this diploma thesis is to find out the influence of volumetric compensations to working accuracy. This thesis consists of detail description of measuring with the aid of Ballbar and Laser Tracer, error compensation of the machine and also designing, machining and measuring of the control work-piece. According to results there is also evaluation of volumetric compensation benefits leading to increasing the working accuracy of measured machine.

Among the latest achievements in gasification technology, one may list the development of a method to preheat gasification agents using switched ceramic honey combs. The best output from this technology is achieved with use of water steam as a gasification agent, which is heated up to 1600 °C. The application of these temperatures with steam as a gasification agent provides a cleaner syngas (no nitrogen from air, cracked tars) and the ash melts into easily utilised glass-like sludge. High hydrogen content in output gas is also favourable for end-user applications.Among the other advantages of this technology is the presumable application of fixed-bed-type reactors fed by separately produced and preheated steam. This construction assumes relatively high steam flow rates to deliver the heat needed for endothermic reactions involving biomass. The biomass is to be heated uniformly and evenly in the volume of the whole reactor, providing easier and simpler control and operation in comparison to other types of reactors. To provide potential constructors and exploiters of these reactors with the kinetic data needed for the calculations of vital parameters for both reactor construction and exploitation, basic experimental research of high-temperature steam gasification of four types of industrially produced biomass has been conducted.Kinetic data have been obtained for straw and wood pellets, wood-chip charcoal and compressed charcoal of mixed origin. Experiments were conducted using two experimental facilities at the Energy and Furnace Division of the Department of Material Science and Engineering (MSE) at the School of Industrial Engineering and Management (ITM) of the Royal Institute of Technology (KTH) and at the Combustion Laboratory of the Mechanical Engineering Department of the University of Maryland (UMD), USA. The experimental facility at the Energy and Furnace Division has been improved with the addition of several constructive elements, providing better possibilities for thermo-gravimetric measurements.The obtained thermo-gravimetric data were analysed and approximated using several models described in the literature. In addition, appropriate software based on the Scilab package was developed. The implementation of the isothermal method based on optimisation algorithms has been developed and tested on the data obtained under the conditions of a slow decrease of temperature in experiments with the char gasification in small-scale experimental facilities in the Energy and Furnace Division.The composition of the gases generated during the gasification of straw and wood pellets by high-temperature steam has been recorded and analysed for different experimental conditions. / <p>QC 20101124</p> / Study of ignition and kinetics of biomass/solid waste thermal conversion with high-temperature air/steam

Fusarium is one of the most important genera of fungi on earth. Many species of Fusarium are well-suited for atmospheric dispersal, yet little is known about their aerobiology. Previous research has shown that large-scale features known as atmospheric transport barriers (Lagrangian coherent structures) guide the transport and mixing of atmospheric populations of Fusarium. The overall goal of this work is to expand our knowledge on the movement and structure of atmospheric populations of Fusarium. The first objective was to monitor changes in colony forming units (CFUs) in atmospheric populations of Fusarium over small time intervals (10 min to several hours). We hypothesized that consecutive collections of Fusarium with unmanned aerial vehicles (UAVs) demonstrate small variations in colony counts. To test this hypothesis, sampling devices on UAVs were separated into two groups, four inner sampling devices opened during the first 10 minutes and four outer sampling devices opened during the second 10 minutes. Results indicated that (1) consecutive collections of Fusarium at 100 m demonstrated small variations in counts and (2) the similarity between collections decreased as the time between sampling intervals increased. The second objective was to determine the structure of atmospheric populations of Fusarium species and relate this to potential source regions. We hypothesized that diverse atmospheric populations of Fusarium are associated with multiple source regions. To test this hypothesis, Fusarium samples were collected with UAVs and identified to the level of species by sequencing a portion of the translation elongation factor 1-alpha gene (TEF-1•). Potential source regions were identified using the atmospheric transport model HYSPLIT. Results indicated that (1) diverse atmospheric populations of Fusarium appeared to be associated with multiple source regions, and (2) the number of Fusarium species collected with UAVs increased with back-trajectory distance of the sampled air. The third objective was to examine the associations between concentrations of populations of Fusarium at ground level (1 m) and in the lower atmosphere (100 m). We hypothesized that concentrations of Fusarium in the atmosphere vary between 1m and 100m. To test this hypothesis, Fusarium was collected with a Burkard volumetric sampler (BVS) and UAVs. Colony counts were converted to spore concentrations (spores per cubic meter of air). Sampling efficiency was used to correct spore concentrations. Results indicated that (1) the distribution of spore concentrations was similar for both samplers over different times of the day, (2) spore concentrations were generally higher in the fall, spring, and summer, and lower in the winter, and (3) spore concentrations were generally higher with BVS samplers than those with UAVs for both hourly and seasonal data. The fourth objective was to assess the ability of strains of Fusarium collected in the lower atmosphere to cause plant disease. We hypothesized that certain isolates of Fusarium collected with UAVs cause plant diseases. To test this hypothesis, we randomly selected isolates of three different species (F. circinatum, F. avenaceum, and F. sporotrichioides) of Fusarium collected with UAVs to inoculate three different hosts (wheat, corn, and pine). Known Fusarium strains were obtained from J. Leslie at Kansas State University as controls. Results indicated showed that the three different isolates tested were able to cause plant diseases in three different hosts (wheat, corn, and pine), confirming that these were potential agents of disease. This work sets the stage for future work examining potential source regions, transport distances, and seasonal patterns of Fusarium. An increased understanding of the dynamics and population structure of plant pathogenic Fusarium in the lower atmosphere is essential for predicting the spread of plant disease and optimizing disease management strategies in the future. / Ph. D.

With the increasing demand of compact and lightweight wireless devices, there is a significant need to miniaturize the antennas, which are one of the largest radiofrequency components. The radiation performance of antennas degrades as their physical size becomes smaller in terms of operating wavelength [1]. The key challenge in antenna design, therefore, lies in the compromise between size and radiation performance. This challenge becomes critical for low frequency antennas such as for the RFID band. The Antenna-in-Package (AiP) concept, where the antenna is realized as part of the package along with the driving electronics, provides some console in terms of size as the antenna does not need any additional space. In this approach, the package becomes a functional module along with its primary job of protecting the components from the environment. This work aims to investigate various miniaturization techniques for a UHF RFID tag on package. Firstly, a dipole is given a 3D shape by carefully folding it over a package, in a manner that the currents on different segments add constructively. Secondly, the package material (which acts as the substrate for the antenna) is chosen to have a dielectric constant of 5.3 which further helps in size reduction. Finally, loading of slow-wave structures, comprising of inductors and capacitors, is used to achieve further miniaturization. The Artificial Transmission Line approach is utilized to determine the required values of the lumped components, and its location is optimized by analyzing the current distribution of the antenna to maintain a good efficiency. The RFID chip with a large capacitive impedance is conjugately matched to the antenna without an external matching network. This is done by carefully selecting the values of the lumped components as well as by adjusting the trace width of the antenna. The package has been realized through a low-loss filament (𝑡𝑎𝑛(𝛿) = 0.004) with the Raise3D Pro2 printer, and the conductor has been realized by copper tape using laser patterning technology with the laser platform PLS6MW. At an operational frequency of 866 MHz, a 𝑘𝑎 of 0.26, a read-range of 2.7 𝑚, and a radiation efficiency of approximately 32% is achieved.

<p>Positive displacement gear machines are widely used in a variety of industrial applications ranging from fuel injection applications to fluid handling systems to fluid power machinery. Simulation models for these machines are increasingly being developed with greater applicability and more accuracy to meet the industry needs. In this work, a research study is done on contact forces in positive displacement gear machines towards improving the accuracy of the simulation models, which can help gain insights on the underlying physics that govern the performance of the machines.</p> <p><br></p> <p>First, the importance of considering contact forces in simulating a positive displacement gear machine is addressed. For this purpose, an orbit motor reference unit is chosen. A multi-domain simulation tool to evaluate the performance of this reference unit, considering contact features, is developed. The approach for creating the simulation tool is based on coupling of different models: pre-processor tools are created that can provide information needed by fluid dynamic model; a 2D CFD model is created that can evaluate leakages through the lubricating gaps based on pressures from fluid dynamic model; and a fluid dynamic model that can accept inputs from other models and evaluate the primary flow of the unit using a lumped parameter approach. This approach allows an accurate prediction of performance characteristics of orbit unit and the results are compared with those of experiments in terms of flow rate (maximum deviation up to 2.5%) and torque (maximum deviation up to 10%). Variation of performance of the unit by modification of contact features is presented, thus drawing the importance of contact forces in simulating a positive displacement gear machine.</p> <p><br></p> <p>After presenting the importance of contact forces, emphasis is placed on creating an accurate model of the traction contact force, in terms of traction coefficient. The traction coefficient is evaluated  by solving a mixed thermal EHL system, for the case of lubricated non-conformal contacts, considering possible asperity effects and temperature change. A few required characteristics of the reference lubricant are obtained using experiments, along with asperity friction coefficient for the lubricant-solid combination for two different roughnesses. The solver is further validated, both in magnitude and trend, against experimental results for the variation of roughness and slide-to-roll ratio of the surfaces. The solver is further used to obtain curve-fit relations of the traction coefficient components with reasonable accuracy.</p> <p><br></p> <p>Lastly, the curve-fit relations of the traction coefficient are used to evaluate the meshing torque loss, and thus the hydro-mechanical efficiency for the case of two external gear machine units, having different gear flank roughnesses. The simulated hydro-mechanical efficiencies are further validated using the results from experiments, with a maximum deviation of up to 3%, but less than 0.5% deviation at many operating conditions. The experimentally obtained variation of hydro-mechanical efficiency with respect to gear flank roughness is captured in the simulations at majority of the operating conditions, thus laying emphasis on the importance of accurate contact force models.</p> <p><br></p> <p>The approaches followed in this work, along with the findings and proven accuracy with experiments, can be considered valuable and can be used to create simulation models that can capture the effects of interference/clearance and gear flank roughness on the performance of positive displacement gear units.</p>

With high quality in graphics being demanded a lot in modern video games, realistic clouds are noexception. In many video games, it is common that its rendering implementation is based on acollection of 2D cloud-images rendered into the scene. Through previously published work, it was found that while other techniques can be more appropriate depending on the project, volumetricrendering is the highest state-of-the-art in cloud rendering. The only lacking feature of this techniqueis the performance rate, as it is a very expensive technique. Two general problems regarding theperformance rate is that either the high quality of the clouds is not applicable to real-time rendering orthe quality has been pushed back to the point where the clouds lacked accuracy or realism in shape. There are three basic objectives to the project that were forumulated so that the aim can be completed. The objectives are listed as the following to satisfy the aim: Aim: Create a cloud generator with the volumetric rendering technique Objective 1: Create a 3D engine in OpenGL that generates clouds with volumetric rendering in real-time. Objective 2: Create different scenes that increase computational cost for the computer to render. Objective 3: Arrange tests across different computers running the engine and document the results in terms of performance. The project is created using the programming language C++ and the OpenGL library in Visual Studio. The code comes from a combination of other previously made projects regarding the subject ofrendering clouds in real-time. In order to save time in the project, two projects created by FedericoVaccaro and Sébastien Hillaire were used as references in order to quickly reach a solid foundation for experimenting with the performance rate of volumetric clouds. The resulting cloud implementation contains three of many cloud types and updates in real-time. It is possible to configure the clouds in real-time and have the density, coverage, light absorption and more be altered to generate between the three different cloud types. When changing the settings for the boxcontaining the clouds, as well as coloring and changing the position of the clouds and global light, the clouds updates in real-time. To conclude the project, rendering the clouds at the goal of above 60 FPS if only limiting the resultsdown to high-end computer was somewhat successful. The clouds visually looked realistic enough inthe scene and the efforts for improving the performance rate did not affect its overall quality. The high-end computer was able to render the clouds but the low-end computer was struggling with theclouds on their own