Advanced Alarm Clock for Windows Phone 7

Práce popisuje vývoj mobilní aplikace pro platformu Windows Phone 7 zaměřené na spánek a následné probuzení uživatele. Aplikace je velice jednoduchá na ovládání a ke své činnosti využívá vestavěných modulů moderních mobilních telefonů, jako je například kamera s vysokým rozlišením a akcelerometr. Práce popisuje hlavní rysy platformy Windows Phone 7, analýzu konkurenčních řešení, samotný návrh vlastní aplikace a její implementaci. Dále tato práce popisuje řešení různých problémů při vývoji a také uvádí příklady použitých metod a nástrojů. V neposlední řadě je zde také uveden seznam použitých knihoven.This bachelor thesis describes the development of mobile application for Windows Phone 7 focused on sleep and awakening the user. The application is very easy to use and uses built-in modules of advanced mobile phones, such as high resolution camera and the accelerometer. This thesis describes the main features of Windows Phone 7 platform, analysis of competing solutions, application concept and its implementation. Furthermore, this work describes the solution of various problems in the development and also provides examples of methods and tools. Finally, there is also a list of used libraries.

Influence of processing techniques on microstructure and mechanical properties of a biodegradable Mg-3Zn-2Ca alloy

New Mg-3Zn-2Ca magnesium alloy was prepared using different processing techniques: gravity casting as well as squeeze casting in liquid and semisolid states. Materials were further thermally treated; thermal treatment of the gravity cast alloy was additionally combined with the equal channel angular pressing (ECAP). Alloy processed by the squeeze casting in liquid as well as in semisolid state exhibit improved plasticity; the ECAP processing positively influenced both the tensile and compressive characteristics of the alloy. Applied heat treatment influenced the distribution and chemical composition of present intermetallic phases. Influence of particular processing techniques, heat treatment, and intermetallic phase distribution is thoroughly discussed in relation to mechanical behavior of presented alloys.Web of Science911art. no. 88

Low Cycle and High Cycle Fatigue Properties of Austempered Ductile Iron

Práce se zabývá posouzením únavových vlastností izotermicky zušlechtěné litiny s kuličkovým grafitem. Na základě nejvhodnější kombinace pevnostních a plastických vlastností určených tahovými zkouškami byla stanovena optimální doba izotermické transformace. Na tomto materiálu byly studovány cyklické odezvy a únavové životnosti v nízkocyklové oblasti jak v módu řízení napětí tak celkové podélné deformace. Všechny experimenty probíhaly při pokojové teplotě. Průběhy křivek cyklického zpevnění-změkčení jsou závislé na velikosti amplitudy zatěžování pro oba módy. Cyklické deformační křivky lze aproximovat mocninnou závislostí. Tyto data byla porovnávána s cyklickými deformačními křivkami stanovenými v obou módech zkrácenými postupy (multiple step test) s ověřením vlivu cyklického creepu na vyšších hladinách u měkkého zatěžování. Experimentální body křivek životnosti jsou v souladu s Manson-Coffinovým a Basquinovými zákonem. Byly porovnávány a diskutovány získané cyklické a únavové parametry. Byla zjišťována únavová životnost ve vysokocyklové oblasti. Experimentálně zjištěnými výsledky byly proloženy vhodné regresní funkce a byly stanoveny regresní parametry jednotlivých funkcí a meze únavy. S využitím nízkocyklových experimentálních dat v módu řízení síly vedla k popisu celé křivky únavové životnosti s příslušnými parametry. Zde nebyla sledována nespojitost experimentálních výsledků. Byla provedena predikce nízkocyklového únavového chování a aproximace tolerančních pásů Wöhlerových křivek pro vysokocyklové výsledky i pro celou oblast únavové životnosti.The thesis is focused on assessment of fatigue behaviour of austempered ductile iron with nodular graphite. Optimal period of transformation was determined based on the best combination of stress and strain characteristics established by tensile test. Cyclic response and low-cycle fatigue life were studied under both stress-control and longitudinal strain-control mode at room temperature. For both modes, shapes of cyclic hardening curves are dependent on stress amplitude. Cyclic deformation curves (CDC) were fitted by power regression function. Results were compared with CDC established by multiple step test in both modes with verification of the influence of cyclic creep (high stress levels, stress-control mode). Experimental data of S-N curves are in agreement with the Manson-Coffin and the Basquin law. Fatigue and cyclic parameters were compared. Fatigue life time in high-cycle fatigue region was determined. Experimental data were fitted by suitable regression functions. Regression parameters and fatigue limit were established by means of each regression function. Experimental data in low- and high-cycle fatigue regions were used to construct S-N curve and to determine relevant parameters. Discontinuity of experimental data was not observed. Low-cycle fatigue behaviour was predicted. Approximation of tolerance bands was realized in high-cycle and both high and low cycle fatigue regions.

Container gantry crane

Cílem této bakalářské práce je návrh funkčních parametrů, nosného rámu a zdvihového ústrojí kolového portálového jeřábu používaného pro manipulaci a stohování kontejnerů v rámci kontejnerového překladiště. Součástí práce je tedy návrh hlavních nosných částí jeřábu včetně pevnostní kontroly a návrhu svarů, výpočty zdvihového ústrojí jeřábu, a také výkresová dokumentace hlavních částí tohoto jeřábu.The aim of this bachelor’s thesis is the design of the main functional parameters, main frame structure and hoisting device of a wheel-mounted gantry crane used for handling and stacking containers within the container terminal. Part of this thesis is therefore the design of main parts of frame structure, including strength proof and weld design, and also calculations of the crane hoisting device and drawings of selected parts of this crane.

Dynamics of Self-Eliminating Gene Drive Mechanisms

Vector-borne diseases continue to be endemic in many parts of the world with dengue, malaria, chikungunya, and yellow fever affecting millions of people every year. Recent advances in genetic engineering, such as CRISPR, have allowed for faster and cheaper DNA modification in organisms with potential to suppress the ability to transmit or carry these pathogens. Additionally, gene drive mechanisms that increase the inheritance rates of transgenic DNA have been proposed, which enable the release of very few transgenic organisms to be capable of transforming entire wild populations. The results of such actions could be irreversible with long-term consequences unknown. Methods to remove transgene DNA have been explored in crops systems and human gene therapy applications. However, such DNA self-elimination mechanisms have not yet been considered to control highly active gene drive transgenes. Here we explore the coupling of three potential gene drive mechanisms (CRISPR, MEDEA, and underdominance) and a proposed self-eliminating mechanism with system dynamics modeling. Our results identify effective parameter spaces for the complete removal of transgenic DNA and restoration of wild-type alleles for all three gene drive mechanisms. Combining gene drive approached with a self-elimination mechanism could allow testing the effects of transgenic populations on the environment, preventing the long-term persistence of the transgene in nature

Influence of Processing Techniques on Microstructure and Mechanical Properties of a Biodegradable Mg-3Zn-2Ca Alloy

New Mg-3Zn-2Ca magnesium alloy was prepared using different processing techniques: gravity casting as well as squeeze casting in liquid and semisolid states. Materials were further thermally treated; thermal treatment of the gravity cast alloy was additionally combined with the equal channel angular pressing (ECAP). Alloy processed by the squeeze casting in liquid as well as in semisolid state exhibit improved plasticity; the ECAP processing positively influenced both the tensile and compressive characteristics of the alloy. Applied heat treatment influenced the distribution and chemical composition of present intermetallic phases. Influence of particular processing techniques, heat treatment, and intermetallic phase distribution is thoroughly discussed in relation to mechanical behavior of presented alloys.New Mg-3Zn-2Ca magnesium alloy was prepared using different processing techniques: gravity casting as well as squeeze casting in liquid and semisolid states. Materials were further thermally treated; thermal treatment of the gravity cast alloy was additionally combined with the equal channel angular pressing (ECAP). Alloy processed by the squeeze casting in liquid as well as in semisolid state exhibit improved plasticity; the ECAP processing positively influenced both the tensile and compressive characteristics of the alloy. Applied heat treatment influenced the distribution and chemical composition of present intermetallic phases. Influence of particular processing techniques, heat treatment, and intermetallic phase distribution is thoroughly discussed in relation to mechanical behavior of presented alloys

Characterization of Powder Metallurgy Processed Pure Magnesium Materials for Biomedical Applications

Magnesium and its alloys are modern lightweight materials applicable in a wide range of industrial fields from aerospace and automotive to biomedical applications. Its main advantages are a good strength to weight ratio and biocompatibility in combination with biodegradability. However, due to the high reactivity of pure Mg and the mechanical properties, not really sufficient for engineering applications, mainly magnesium alloys are used. Good mechanical properties of magnesium and its alloys can be furthermore significantly upgraded by decreasing the grain size, nowadays performed mainly via severe plastic deformation (SPD) techniques, powder metallurgy (PM) processing or by a combination of both method

Structural and functional basis of mammalian microRNA biogenesis by Dicer

MicroRNA (miRNA) and RNA interference (RNAi) pathways rely on small RNAs produced by Dicer endonucleases. Mammalian Dicer primarily supports the essential gene-regulating miRNA pathway, but how it is specifically adapted to miRNA biogenesis is unknown. We show that the adaptation entails a unique structural role of Dicer’s DExD/H helicase domain. Although mice tolerate loss of its putative ATPase function, the complete absence of the domain is lethal because it assures high-fidelity miRNA biogenesis. Structures of murine Dicer⋅miRNA precursor complexes revealed that the DExD/H domain has a helicase-unrelated structural function. It locks Dicer in a closed state, which facilitates miRNA precursor selection. Transition to a cleavage-competent open state is stimulated by Dicer-binding protein TARBP2. Absence of the DExD/H domain or its mutations unlocks the closed state, reduces substrate selectivity, and activates RNAi. Thus, the DExD/H domain structurally contributes to mammalian miRNA biogenesis and underlies mechanistical partitioning of miRNA and RNAi pathways

Únavové vlastnosti hořčíkové slitiny AZ91

The paper deals with the determination of principal mechanical properties and the investigation of fatigue behaviour of AZ91 magnesium alloy. The experimental material was made by squeeze casting technique and heat treated to obtain T4 state (solution annealing), when hard, brittle Mg17Al12 intermetallic phase is dissolved. The basic mechanical properties (Young’s modulus, ultimate tensile strength, yield strength, elongation to fracture and reduction of area) were determinated by static tensile test. Furthermore, fatigue parameters were investigated and standard tensile curve was compared with cyclic stress-strain curve. The comparison indicates that studied material exhibited cyclic hardening at whole lifetime. In addition, the S-N curve on the basis of smooth test bars tested under symmetrical push-pull loading at room temperature was evaluated. The measured data were subsequently used for assessing the Manson-Coffin curve and for fitting with suitable regression function for determination of the fatigue parameters. Fatigue limit σC of the studied alloy for 108 cycles is approaching 50 MPa. Structure of the studied alloy in the basic state and after heat treatment was observed by light and scanning electron microscopy.Práce je zaměřena na stanovení základních mechanických charakteristik a zkoumání únavového chování slitiny hořčíku AZ91. Studovaná slitina byla vyrobena metodou squeeze casting a tepelně zpracována na stav T4 (tj. rozpouštěcí žíhání), které způsobuje rozpouštění tvrdé, křehké intermetalické fáze Mg17Al12. Byla provedena statická zkouška tahem a stanoveny napěťové a deformační charakteristiky (modul pružnosti, mez pevnosti, mez kluzu, tažnost a kontrakce). Dále bylo provedeno měření únavových parametrů a srovnána jednosměrná tahová křivka s cyklickou deformační křivkou. Z tohoto srovnání vyplynulo, že studovaný materiál cyklicky zpevňuje. Na hladkých zkušebních tělesech při symetrickém namáhání tah-tlak za normální teploty byla naměřena Wöhlerova-Basquinova závislost a odvozená Mansonova-Coffinova křivka zkoumaného materiálu. Experimentálně naměřená data byla proložena vhodnou regresní funkcí a stanoveny únavové parametry. Mez únavy σC studované slitiny pro hladká zkušební tělesa určená pro 108 cyklů se blíží 50 MPa. Struktura studované slitiny v základním stavu a po tepelném zpracování byla pozorována světelným a rastrovacím elektronovým mikroskopem