EMG biofeedback

Bakalářská práce popisuje základní metody získávání elektromyografických dat invazivním a neinvazivním způsobem. Dále se zaměřuje na princip biologické zpětné vazby, na myofeedback a jeho základní vlastnosti. Součástí práce je aplikace, která umožňuje zobrazení měřeného průběhu EMG, signalizuje překročení nastaveného prahu a obsahuje dvě jednoduché hry vhodné pro myofeedback.The bachelor´s thesis describes the basic methods of bringing out the electromyographic data by invazive and noninvazive procedure. Further it is focused on the principle of the biological feedback and on the myofeedback and its essential characteristics. The created application can displays the progression of the maesured EMG, signalizes the overrun of the set up threshold and contains two simply games for myofeeedback.

Directed Energy Deposition of Ni-Mn-Ga Magnetic Shape Memory Alloy

Processing of magnetic shape memory alloys – active materials that show strains of up to 12 % in a magnetic field and that are being targeted for application as actuators, sensors and energy harvesters – suffers from challenges including time intensive production and macrosegregation that leads to reduced yield. Furthermore, the brittle mechanical behavior of these materials largely eliminates the possibility of machining for a desired shape. This work explores directed energy deposition, an additive manufacturing or “3D printing” process, as an alternative processing route for Ni Mn Ga magnetic shape memory alloy. The magnetic properties, transformation behavior, and composition of the feedstock powder and deposits resulting from a laser metal deposition process are investigated against varied laser power. All samples are seen to possess favorable magnetic behavior and potentially favorable phase for magnetic field induced strain (MFIS) to take place. Additionally, the microstructure of the deposited samples is observed and its special features that may aid MFIS are discussed. Most notably, this thesis presents possible evidence of twin variants crossing deposition layers and of twin boundary motion in a magnetic field. Finally, a connection between lower laser power and reduced loss of Mn is considered

Characterization of hierarchical structures in remelted Ni-Mn-Ga substrates for directed energy deposition manufacturing of single crystals

Magnetic shape-memory alloys (MSMAs) such as Ni-Mn-Ga Heusler alloys have been of great interest in the past decade due to the observed inverse magnetoplastic (IMP) effect, wherein an applied mechanical stress reorients the direction of easy magnetization of the crystal. However, practically large strains achieved with this mechanism may only be generated from single crystals, the manufacturing of which is traditionally time-intensive and delicate. A possible approach for more quickly producing single crystal MSMAs is to use directed energy deposition (DED), a type of laser additive manufacturing. This study focused on the laser remelting of an austenitic Ni51Mn24.4Ga24.6 single crystal substrate without deposition of an additional layer, so as to observe the effects of varying laser power and travel velocity on the resulting melt pool. Using digital microscopy and image analysis, various properties of the melt pool and contained microstructures were measured as functions of laser power and travel velocity. Some trends were suggested that provided insight into which parameter values are conducive to retention of a single crystal; however, a more comprehensive study is needed to confirm these trends

Memories of Nýrsko dam

Příspěvek je věnován přehradě Nýrsko, především pak různým aspektům, na které pamětníci mající přímou zkušenost s výstavbou vzpomínají. Jedná se tak například o pozici techniky a technologie užité při výstavbě vodního díla v porovnání s osobními zkušenostmi či znalostmi reálií výstavby přehrad jiných na našem území. Práce také seznamuje s okolnostmi, které výstavbu provázeli, a které jsou zajímavé z hlediska dobového, jako například lokace, v níž je přehrada situována, či z hlediska přístupu k pramenům a možnému směru budoucího výzkumu.This paper is concerned with Nýrsko dam, especially with various aspects that the eyewitnesses who have direct experience with the construction recall. It is, for example, the position of techniques and technology used during the construction of the dam and its comparison with personal experience or knowledge concerning construction of other dams in our country. This work also presents the circumstances that accompanied the construction, and are interesting in terms of period, such as the location of the dam, or in terms of access to the sources and possible direction of future research

Development of a post-processing method for estimating solidification parameters from finite-element modeling of laser remelting in directed energy deposition of Ni-Mn-Ga magnetic shape-memory alloy single crystals

Directed energy deposition is a subset of laser additive manufacturing which has been suggested as a feasible method for producing single crystals of metal alloys such as Ni-Mn-Ga magnetic shape-memory alloys. However, relating the thermal parameters, specifically the solidification front growth velocity V and thermal gradient G to the operational parameters, specifically the nominal laser power and travel velocity, is challenging. Therefore, this work aimed to use finite-element analysis (FEA) to create thermal models which allow for the determination of G and V for operational parameter combinations. Comparison with experimental data allowed for association of the range of G and V with the samples that best displayed single crystal growth. It was found that a high power and medium-low travel velocity is most likely to result in single crystal growth

Transfer of Ochratoxin A into Tea and Coffee Beverages

International audienceOchratoxin A (OTA) is nephrotoxic, hepatotoxic, immunotoxic, neurotoxic, reprotoxic, teratogenic, and carcinogenic (group 2B), being characterized by species and sex differences in sensitivity. Despite the fact that OTA is in some aspects a controversial topic, OTA is the most powerful renal carcinogen. The aim of this study was to make a small survey concerning OTA content in black tea, fruit tea, and ground roasted coffee, and to assess OTA transfer into beverages. OTA content was measured using a validated and accredited HPLC-FLD method with a limit of quantification (LOQ) of 0.35 ng/g. The OTA amount ranged from LOQ up to 250 ng/g in black tea and up to 104 ng/g in fruit tea. Black tea and fruit tea, naturally contaminated, were used to prepare tea infusions. The transfer OPEN ACCESS Toxins 2014, 6 3439 from black tea to the infusion was 34.8% ± 1.3% and from fruit tea 4.1% ± 0.2%. Ground roasted coffee naturally contaminated at 0.92 ng/g was used to prepare seven kinds of coffee beverages. Depending on the type of process used, OTA transfer into coffee ranged from 22.3% to 66.1%. OTA intakes from fruit and black tea or coffee represent a non-negligible human source

Additive Manufacturing: Opportunities and Challenges for Functional Magnetic Materials

Additive manufacturing (AM), also known as 3D printing, is transforming manufacturing due to a highly digital approach, the ability to near-net shape manufacture highly complex internal and external shapes of nearly any material, and targeted pore and grain microstructure (thus, properties)

High-speed data switch

Diplomová práce je zaměřena na návrh ethernetového vysokorychlostního přepínače dat, který je založený na obvodu FPGA. Přepínač bude schopný rozdělit datový tok tvořený ethernetovými rámci na dva toky s polovičním datovým tokem.The master’s thesis is focused on desing high-speed ethernet switch based on circuit FPGA. The switch is able to divide one data stream, created from ethernet frames to the two data streams with half data flow.

American roots music legacy in the songs of Bruce Springsteen

Tato práce zkoumá vliv americké tradiční hudby, včetně všech zdrojů její inspirace, na písně Bruce Springsteena. Zaměřena je především na rozbor dvou trilogií a to především z hlediska textů a jejich návaznosti na americkou hudební tradici. Pro lepší pochopení Springsteenovy tvorby je poskytnuta jak krátká biografie, tak politické pozadí.Katedra anglického jazykaObhájenoThis undergraduate thesis deals with the influence of American roots music, including all of its sources of inspiration, on the songs of Bruce Springsteen. It mainly analyses two trilogies with accent on its lyrical connection to the American music tradition. For better comprehension of Springsteen's works, a brief biography and a political background are provided

Comparison of the solar photosphere and chromosphere based on their observations and images from the Internet

Popis základních fyzikálních jevů na Slunci.Metody pozorování fotosféry a chromosféry Slunce. Společné jevy v chromosféře a fotosféře Slunce.Návod na pozorovací protokoly. Zpracování dat z pozorování. Snímky dostupné na internetu a jejich porovnání s pozorováním.Katedra matematiky, fyziky a technické výchovyObhájenoDescription of basic physical phenomena in the photosphere and observations Slunci.Metody Sun chromosphere. Common phenomena in the chromosphere and photosphere Slunce.Návod the observation protocols. Processing of data from observations. Images available on the Internet and their comparison with observations