Determination of Flow Rate Using Ultrasonic Sensing for Water Quality Monitoring

To monitor the water quality of a stream or river, one must accurately and continuously measure the flow rate. The goal of this project is to build an inexpensive, accurate, and reliable flow meter that will provide continuous flow rate data. Our meter design operates by using an ultrasonic sensor to determine the height of the stream as it passes over a weir. This height can be directly related to the flow rate of the stream. By combining flow data with other water quality measures (e.g., phosphorous concentration), one can quantitatively characterize the health of the stream

Sady pro ovoce, ne pro dotace

Ve dnech 17. až 19. dubna 2013 se mohli zájemci o ekologické hospodářství zúčastnit semináře s názvem Ekologické intenzivní sady, zakládání, péče a ochrana, který se konal v Dětenicích pod vedením švýcarského odborníka Andrease Häseliho. Ten se věnuje výzkumu v ekologickém zemědělství již 30 let. Většinu účastníků semináře tvořili členové neziskových organizací, pedagogové a výzkumníci

Integration of Higher-Order Physics in the Community Ice Sheet Model: Scientific and Software Concerns

The Community Ice Sheet Model (CISM) is a next-generation land ice model that is designed to answer important questions regarding the response of Earth’s land ice to climate forcing. The program extends Glimmer, an ice sheet model based on the shallow ice approximation. This thesis concerns a project to ready CISM for these questions by integrating an ice velocity diagnostic based on a first-order approximation of the Navier-Stokes equations. I present in detail the derivation of the first-order momentum balance equations for both the interior of an ice sheet and a variety of boundary conditions. I discuss the numerical techniques used to build and solve a finite difference approximation of these equations, as well as the software engineering process and design solutions used to integrate this model with the rest of CISM. I then build a case for the correctness of the integrated model by presenting the results of numerous experiments that compare this model to data, exact solutions, and a collection of similar models. I find that in most cases the integrated model performs favorably in model intercomparisons and in comparisons to exact solutions. I finally present possible future directions for the CISM project with respect to higher-order ice modeling, as well as lessons learned for future maintainers

The Effects of Background Stress on Cardiovascular Responses to Acute Stress

The goal of this study was to investigate further the nature of the relationship between background stress and cardiovascular response to relationships between mood and background stress, and background stress and psychological distress were also explored. The background stress levels of 59 undergraduate students were measured using the Perceived Stress Scale (PSS). Measures of psychological distress were taken using the General Health Questionnaire-12 (GHQ-12), mood was assessed with the Brief Mood Induction Scale (BMIS), and other relevant data were collected. Systolic blood pressure, diastolic blood pressure and heart rate were measured through three 8-minute test periods, an 8-minute Mood Induction Task, and a 3-minute Mental Arithmetic Task. It was hypothesized that a positive correlation would be present between PSS measures and cardiovascular reactivity, due to the majority of research supporting a theory of heightened reactivity in individuals with higher stress. There was a significant period main effect for all three cardiovascular measures, indicating that the Mental Arithmetic Task did produce reactivity above rest. However, data analyses indicated that there was no significant correlation between background stress and reactivity. It was also hypothesized that there would be a significant positive correlation between PSS measures and changes in negative mood during the Mood Induction Task. T-tests of before and after measures of mood variable acute stress. Possible iv scores on the BMIS indicated change in mood, showing that the mood induction worked. Analyses of data showed no relationship between PSS or GHQ measures and change in negative mood. Hypothesis 3 stated that there would be a significant positive correlation between PSS and GHQ measures, There was evidence of a significant correlation between background stress and measures for psychological distress. It is concluded that the relationship between background stress and reactivity may have a complexity requiring more detailed knowledge of subjects’ stress. There is not enough evidence, based on the data collected, to draw conclusions about the relationship between PSS and change in negative mood. Finally, strong correlation between PSS and GHQ measures is supported by prior research. Further research into the relationship between background stress and psychological stress may be of interest

Boundary Nodes Detection in Wireless Sensor Networks

V teoretické části diplomové práce je popsáno několik známých algoritmů a nový přístup k detekci hraničních uzlů v bezdrátových senzorových sítích. Nový algoritmus BRB byl inspirován nedostatky předešlých algoritmů a jeho hlavní nosnou myšlenkou, je výběr několika sousedních bodů (B, C). Přístup algoritmu BRB je decentralizovaně detekovat uzly ležící na hranici sítě. Praktická část porovnává několik algoritmů s novým BRB. Vyhodnoceno je množství výskytu úspěšně a chybně určených hraničních uzlů v ideálním i reálném prostředí. Výsledky simulace dokázaly, že navržený algoritmus představuje efektivní řešení pro přesnou detekci hraničních uzlů v bezdrátových senzorových sítích.Theoretical part of thesis describes several known algorithms and new approaches for the bourder node detection in a wireless sensor networks. The new algorithm BRB was inspired by failures of previous algorithms and its major supporting idea is select several neighboring points (B, C). Approach algorithm BRB is a decentralized detection of nodes located at the perimeter. The practical part compares several algorithm with the new BRB algorithm. Quantity of successful and false detection of boundary nodes was evaluated in ideal and real environment.The simulation results shown, that the proposed algorithm is effective solution for accurate border node detection in wireless sensor networks.

Production Rationalization of Die Punch

Práce byla zaměřena na racionalizaci výroby matrice střižníku, který je využíván při lisování. Tato matrice střižníku je umístěna v nástroji, který obsahuje několik takovýchto matric. Původně byla tato matrice z důvodu složitosti vyráběna na starším elektroerozivním stroji. Kvůli časté výměně těchto matric se klade důraz na zvýšení přesnosti a kvality s ohledem na udržení nebo snížení výrobních nákladů. Původní zastaralé stroje dosahovaly dostatečných přesností, ale při dosažení vyšší kvality a přesnosti dosáhneme zvýšení životnosti nástroje. V teoretické části bude pozornost věnována podstatě a principu nekonvenčních principů obrábění, a to převážně elektroerozivnímu obrábění. Praktická část diplomové práce bude zaměřena na volbu strojů, druhy řezných drátů, volbě optimálních podmínek pro nekonvenční obrábění a výsledné jakosti povrchu. Bude posuzován vliv volby stroje, řezných podmínek, technologii postupu na výslednou výrobu matrice. V závěrečné části diplomové práce bude posuzováno technicko – ekonomické zhodnocení a vyhodnocení volby stroje na výrobu matrice střižníku.his thesis was focused on the production rationalization of Die Punch, which is used during the pressing. This matrix is placed in a punch tool which contains several of these matrices. Originaly was this matrix manufactured on an older type of machine, because of the complexity of the process. The main emphasis, due to the frequent replacement of these matrices, was placed on increasing the accuracy and quality with regard to maintaining or redcing the cost of production. Original old machines achieved sufficient accuracy, but we are able to achieve a longer life service of a tool at a higher quality and accuracy. The work was focused on the rationalization of production punch matrix, which is used during pressing. This matrix is placed in a punch tool that contains several such matrices. Originally the matrix, because of the complexity electro manufactured on older machines. Due to the frequent replacement of these matrices with emphasis on increasing the accuracy and quality with regard to maintaining or reducing production costs. Original obsolete machines achieve sufficient accuracy, but at a higher quality and accuracy achieved an increase in tool life. The theoretical section will focus on the essence and principle of non-conventional machining, mostly elektroinvasive machining. The practical part is focused on the choice of machine, types of cutting wires, the choice of optimal conditions for unconventional machining and the resulting surface finish. The influence of elections machines, cutting conditions, the technology of progress will be considered to the final production of the matrix. In the final part of this thesis, the technical – economic evaluation and assessment of election machines of Die punch will be considered.346 - Katedra obrábění, montáže a strojírenské metrologievýborn