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The growing use of DC/DC power converters has resulted in the requirement that their complex controllers be cheaper and smaller, thus using cost-effective implementations. For this purpose, it is necessary to decrease the computational burden in controller implementation to minimize the hardware requirements. This manuscript presents two methods for tuning an adaptive linear–quadratic–Gaussian voltage controller for a battery charger/discharger, implemented with a Sepic/Zeta converter, to work at any operating point. The first method is based on a lookup table to select, using the nearest method, both the state feedback vector and the observer gain vector, solving the Riccati’s differential equation offline for each practical operating point. The second method defines a polynomial function for each controller element that is based on the previous data corresponding to the system operating points. The adaptability of the two controllers to fixed voltage regulation and reference tracking was validated using simulations and experimental tests. The overshoot and settling time results were lower than 11% and 3.7 ms, which are in the same orders of magnitude of a control approach in which the equations are solved online. Likewise, three indices were evaluated: central processing unit capacity, cost, and performance. This evaluation confirms that the controller based on polynomial interpolation is the best option of the two examined methods due to the satisfactory balance between dynamic performance and cost. Despite the advantages of the controllers in being based on a lookup table and polynomial interpolation, the adaptive linear–quadratic–Gaussian has the benefit of not requiring an offline training campaign; however, the cost saving obtained with the lookup table controllers and polynomial interpolation controllers, due to the possible implementation on small-size microcontrollers with development tool simple and easy maintenance, will surely be desirable for a large number of deployed units, ensuring that those solutions are highly cost-effective.

The aim of this thesis was to compare the performance of two relational database management systems PostgreSQL and MySQL. For the purpose of the study a relational database was designed and a piece of software was implemented to connect desktop application with the database system. This software shall also create entities and relations between them in desired empty schemes on servers for databases. There has also been implemented a desktop application in Java programming language, that allows browsing data stored in database and performing the tests of database performance. Tests addressed basic operations of adding, collecting, updating and deleting data. Thisthesis makes a hypothesis "PostgreSQL is more efficient for desktop application while loaded with small data, in that case 1000 of queries", that was confirmed by achieved results from tests performed.

Background Wearable sleep monitors are of high interest to consumers and researchers because of their ability to provide estimation of sleep patterns in free-living conditions in a cost-efficient way. Objective We conducted a systematic review of publications reporting on the performance of wristband Fitbit models in assessing sleep parameters and stages. Methods In adherence with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, we comprehensively searched the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane, Embase, MEDLINE, PubMed, PsycINFO, and Web of Science databases using the keyword Fitbit to identify relevant publications meeting predefined inclusion and exclusion criteria. Results The search yielded 3085 candidate articles. After eliminating duplicates and in compliance with inclusion and exclusion criteria, 22 articles qualified for systematic review, with 8 providing quantitative data for meta-analysis. In reference to polysomnography (PSG), nonsleep-staging Fitbit models tended to overestimate total sleep time (TST; range from approximately 7 to 67 mins; effect size=-0.51, P Conclusions Sleep-staging Fitbit models showed promising performance, especially in differentiating wake from sleep. However, although these models are a convenient and economical means for consumers to obtain gross estimates of sleep parameters and time spent in sleep stages, they are of limited specificity and are not a substitute for PSG.

Comparison of Athletics Records of Intellectually Disabled Persons with Records of Intact Athletes Comparative studies between intact and ID (Intellectually Disabled) individuals have been carried out in many areas (psychic, somatic characteristics, motor skills of individuals with ID, comparison of the level of intellect and motor performance). The study compares the records of intellectually disabled athletes with the records of majority population athletes. For comparison, we have used the existing world records registered by the International Association of Athletics Federations (IAAF), and Inas, (International Sports Federation for Persons with Intellectual Disability). To compare the best Czech records with world records, the best performances of women registered by the ČSMPS (Czech Sports Association for the Mentally Handicapped) were used. If we compare the World Records (IAAF and Inas), we can find differences ranging from 8.2 to 45.3%. The differences between intact and intellectually disabled men are approx. by 2 to 10% lower than in women’s similar events. It is only in three events that the differences between intact and ID are slightly lower in women than in men (high jump, discus throw, javelin throw). The smallest differences between the IAAF and Inas records are in sprints events and middle running distances of men and women (10% men, or 15% women respectively). The differences in long distances reach 18% (men) and 23% (women). The differences in jumping events are very different, accounting for 20% for men and 24% for women with some generalization. Throwing events for practically both sexes bring differences above 40% (except for shot put). Srovnání atletických rekordů intelektově postižených osob s rekordy intaktních sportovců Srovnávací studie mezi IP a intaktními byly realizovány v řadě oblastí (psychika, somatické charakteristiky, motorika jedinců s IP, srovnání úrovně intelektu a motorické výkonnosti). Studie přináší srovnání rekordních výkonů intelektuálně postižených atletů s rekordy sportovců většinové populace. Pro komparaci jsme využili stávající světové rekordy vedené mezinárodní atletickou federací IAAF a Inas, (mezinárodní organizací pro paralelní sport pro osoby s intelektovým postižením). Pro srovnání českých nejlepších atletek se světem byly využity rekordy ČSMPS (Českého svazu mentálně postižených sportovců, žen). Ze srovnání světových rekordů (IAAF a Inas) vyplývají diference na úrovni 8,2–45,3 %. Diference mezi intaktními a intelektově postiženými muži jsou o cca 2–10 % nižší než u obdobných disciplín žen. Pouze u tří disciplín jsou rozdíly mezi intaktními a IP u žen nepatrně nižší nežli u mužů (skok vysoký, hod diskem, hod oštěpem). Nejmenší rozdíl mezi rekordy IAAF a Inas je u sprintů a středních tratí mužů i žen (10 % u mužů, resp. 15 % u žen) Rozdíly na dlouhých tratích dosahují 18 % (u mužů) a 23 % (u žen). Ve skokanských disciplínách jsou diference velmi různé, při určitém zobecnění 20 % u mužů a 24 % u žen. Vrhačské disciplíny prakticky u obou pohlaví přináší rozdíly nad 40 % (vyjma vrhu koulí).

A utilização da tecnologia de digestão anaeróbia (biometanização) para a gestão da fração orgânica dos resíduos sólidos urbanos é uma realidade que vem se disseminando mundialmente. Os sistemas via seca vem se destacando pela maior robustez do sistema biológico e pela minimização da geração de efluentes líquidos. Para avaliar o desempenho de sistemas de digestão via seca, foram realizadas visitas técnicas a plantas das principais tecnologias - Valorga, Laran, Kompogas e Dranco - e, a partir de constatações in loco e de dados levantados junto aos fabricantes, elaborou-se uma metodologia para avaliação das mesmas, com 35 indicadores, divididos em 4 grupos (Histórico; Aspectos Operacionais; Desempenho de Projeto; Desempenho Real). Na soma ponderada, as tecnologias que obtiveram os dois melhores desempenhos foram aquelas denominadas de 4 e 2, respectivamente, que empregam digestor retangular horizontal com agitação mecânica por pás com eixo no sentido transversal ao fluxo do material em digestão.The employment of anaerobic digestion technology (biomethanation) for the management of the organic fraction of municipal solid waste is a reality that has been spreading out all around the world. The dry biomethanation, in particular, has been highlighted due to its biological system higher robustness and to the low generation of liquid effluents. In order to assess the dry biomethanation technologies performance, technical visits were carried out at different plants representing the major technologies available - Valorga, Laran, Kompogas, and Dranco - and, based on in situ observations as well as on projected performance data, it was developed an assessment methodology, composed by 35 indexes, divided into 4 groups: Historic; Operational Aspects; Projected Performance; Real Performance. After all, the best performance was presented by technologies referred to as 4 and 2 that employs rectangular horizontal digesters stirred by impellers with axis across the flux of the digesting material.

Large-scale hydrological models are important de- cision support tools in water resources management. The largest source of uncertainty in such models is the hydros- tratigraphic model. Geometry and configuration of hydroge- ological units are often poorly determined from hydrogeo- logical data alone. Due to sparse sampling in space, litholog- ical borehole logs may overlook structures that are impor- tant for groundwater flow at larger scales. Good spatial cov- erage along with high spatial resolution makes airborne elec- tromagnetic (AEM) data valuable for the structural input to large-scale groundwater models. We present a novel method to automatically integrate large AEM data sets and lithologi- cal information into large-scale hydrological models. Clay- fraction maps are produced by translating geophysical re- sistivity into clay-fraction values using lithological borehole information. Voxel models of electrical resistivity and clay fraction are classified into hydrostratigraphic zones usingk- means clustering. Hydraulic conductivity values of the zones are estimated by hydrological calibration using hydraulic head and stream discharge observations. The method is ap- plied to a Danish case study. Benchmarking hydrological per- formance by comparison of performance statistics from com- parable hydrological models, the cluster model performed competitively. Calibrations of 11 hydrostratigraphic cluster models with 1-11 hydraulic conductivity zones showed im- proved hydrological performance with an increasing num- ber of clusters. Beyond the 5-cluster model hydrological per- formance did not improve. Due to reproducibility and pos- sibility of method standardization and automation, we be- lieve that hydrostratigraphic model generation with the pro- posed method has important prospects for groundwater mod- els used in water resources management.

A utilização da tecnologia de digestão anaeróbia (biometanização) para a gestão da fração orgânica dos resíduos sólidos urbanos é uma realidade que vem se disseminando mundialmente. Os sistemas via seca vem se destacando pela maior robustez do sistema biológico e pela minimização da geração de efluentes líquidos. Para avaliar o desempenho de sistemas de digestão via seca, foram realizadas visitas técnicas a plantas das principais tecnologias - Valorga, Laran, Kompogas e Dranco - e, a partir de constatações in loco e de dados levantados junto aos fabricantes, elaborou-se uma metodologia para avaliação das mesmas, com 35 indicadores, divididos em 4 grupos (Histórico; Aspectos Operacionais; Desempenho de Projeto; Desempenho Real). Na soma ponderada, as tecnologias que obtiveram os dois melhores desempenhos foram aquelas denominadas de 4 e 2, respectivamente, que empregam digestor retangular horizontal com agitação mecânica por pás com eixo no sentido transversal ao fluxo do material em digestão. The employment of anaerobic digestion technology (biomethanation) for the management of the organic fraction of municipal solid waste is a reality that has been spreading out all around the world. The dry biomethanation, in particular, has been highlighted due to its biological system higher robustness and to the low generation of liquid effluents. In order to assess the dry biomethanation technologies performance, technical visits were carried out at different plants representing the major technologies available - Valorga, Laran, Kompogas, and Dranco - and, based on in situ observations as well as on projected performance data, it was developed an assessment methodology, composed by 35 indexes, divided into 4 groups: Historic; Operational Aspects; Projected Performance; Real Performance. After all, the best performance was presented by technologies referred to as 4 and 2 that employs rectangular horizontal digesters stirred by impellers with axis across the flux of the digesting material.