Sharing Part of the Screen

Tato práce se zabývá způsobem sdílení části obrazovky mezi více uživateli. Je v~ní popsaný návrh takové aplikace, která, kromě samotného sdílení, nabízí možnost upravovat tyto snímky jeste před jejich odesláním. Samozřejmostí je i~návrh textové komunikace mezi uživateli, kteří mohou o~snímcích společně diskutovat. V~práci je také uvedený způsob implementace tohoto programu a v~závěru se nachází návrh, jak je možné tuto aplikaci v~budoucnosti vylepšit.This bachelor's thesis deals with the manner of the screen sharing among multiple users. There is described a~proposal for such application, which in addition to sharing offers the ability to edit the images before sending them. Of course there is a~draft text communication between users, who can discuss the images together. The paper also indicates the implementation of this program and there is a~proposal to this application in the end, how is it possible to improve it in the future.

Analysis and Prediction from GPS Data

Tato práce řeší analýzu sesbíraných GPS dat a na základě nich možnosti predikce nejvýhodnější trasy vypočítané za pomocí aplikace napsané ve skriptovacím jazyce PHP. Výhodnost trasy se posuzuje podle vzdálenosti, doby jízdy a převýšení. V práci je dále popsaný systém GPS, formát zdrojových dat a způsob jejich uložení do vhodné databáze. Nechybí ani popis hledání nejkratší cesty v grafu a několik nejznámějších algoritmů na její nalezení. Práce zahrnuje i popis implementace spracování nových dat a pozdější vyhledávání nad týmito datami ve skriptovacím jazyce PHP. V závěru je zhodnocený přínos této aplikace a návrh, jak je ji možné v budoucnosti vylepšit.This paper deals with the analysis of the collected GPS data and the possibility of the prediction of most advantageous route on its basis, by the application written in the PHP scripting language. The suitability of the route is considered by the distance, driving time, or elevation. The thesis also describes a GPS system, the format of the source data and their storing in an appropriate database. There is also a description of the search of the shortest path in the graph and some famous algorithms for finding it. The paper includes information about implementation of new data integration and path finding within this data in PHP scripting language. In conclusion it is evaluated what are the benefits of this application and design saying how this application can be improved in the future.

Atmospheric pressure plasma assisted calcination of composite submicron fibers

The plasma assisted calcination of composite organic/inorganic submicron fibers for the preparation of inorganic fibers in submicron scale was studied. Aluminium butoxide/polyvinylpyrrolidone fibers prepared by electrospinning were treated using low-temperature plasma generated by special type of dielectric barrier discharge, so called diffuse coplanar surface barrier discharge (DCSBD) at atmospheric pressure in ambient air, synthetic air, oxygen and nitrogen. Effect of plasma treatment on base polymer removal was investigated by using Attenuated total reflectance – Fourier transform infrared (ATR-FTIR) spectroscopy. Influence of working gas on the base polymer reduction was studied by energy-dispersive X-ray spectroscopy (EDX) and CHNS elemental analysis. Changes in fibers morphology were observed by scanning electron microscopy (SEM). High efficiency of organic template removal without any degradation of fibers was observed after plasma treatment in ambient air. Due to the low-temperature approach and short exposure time, the plasma assisted calcination is a promising alternative to the conventional thermal calcination

Changes in Surface Characteristics of BOPP Foil after Treatment by Ambient Air Plasma Generated by Coplanar and Volume Dielectric Barrier Discharge

Biaxially oriented polypropylene (BOPP) is a highly transparent polymer defined by excellent mechanical and barrier properties applicable in the food packaging industry. However, its low surface free energy restricts its use in many industrial processes and needs to be improved. The presented study modifies a BOPP surface using two different atmospheric-pressure plasma sources operating in ambient air and capable of inline processing. The volume dielectric barrier discharge (VDBD) and diffuse coplanar surface barrier discharge (DCSBD) were applied to improve the wettability and adhesion of the 1–10 s treated surface. The changes in morphology and surface chemistry were analyzed by SEM, AFM, WCA/SFE, and XPS, and adhesion was evaluated by a peel force test. Comparing both plasma sources revealed their similar effect on surface wettability and incorporation of polar functional groups. Additionally, higher surface roughness in the case of VDBD treatment contributed to slightly more efficient adhesion in comparison to DCSBD. Although we achieved comparable results for both plasma sources in the term of enhanced surface wettability, degree of oxidation, and stability of induced changes, DCSBD had less effect on the surface deterioration than VDBD, where surface structuring caused an undesirable haze

Enhancement of carbon-steel peel adhesion to rubber blend using atmospheric pressure plasma

The surface of carbon-steel plates was modified by non-equilibrium plasma of diffuse coplanar surface barrier discharge (DCSBD) in order to improve the adhesive properties to the NR (natural rubber) green rubber compound. The effect of different treatment times as well as different input power and frequency of supplied high voltage was investigated. The samples were characterized using contact angle and surface free energy measurement, measurement of adhesive properties, scanning electron microscopy (SEM) and atomic force microscopy (AFM). Surface chemical composition was studied by energy-dispersive X-ray spectroscopy (EDX). Significant increase in wettability was observed even after 2 s of plasma exposure. The surface modification was confirmed also by peel test, where the best results were obtained for 6 s of plasma treatment. In addition the ageing effect was studied to investigate the durability of modification, which is crucial for the industrial applications

Selective Plasma Etching of Polymer-Metal Mesh Foil in Large-Area Hydrogen Atmospheric Pressure Plasma

We present a novel method of surface processing of complex polymer-metal composite substrates. Atmospheric-pressure plasma etching in pure H2, N2, H2/N2 and air plasmas was used to fabricate flexible transparent composite poly(methyl methacrylate) (PMMA)-based polymer film/Ag-coated Cu metal wire mesh substrates with conductive connection sites by the selective removal of the thin (~10–100 nm) surface PMMA layer. To mimic large-area roll-to-roll processing, we used an advanced alumina-based concavely curved electrode generating a thin and high-power density cold plasma layer by the diffuse coplanar surface barrier discharge. A short 1 s exposure to pure hydrogen plasma, led to successful highly-selective etching of the surface PMMA film without any destruction of the Ag-coated Cu metal wires embedded in the PMMA polymer. On the other hand, the use of ambient air, pure nitrogen and H2/N2 plasmas resulted in undesired degradation both of the polymer and the metal wires surfaces. Since it was found that the etching efficiency strongly depends on the process parameters, such as treatment time and the distance from the electrode surface, we studied the effect and performance of these parameters

Growth Stimulation of Durum Wheat and Common Buckwheat by Non-Thermal Atmospheric Pressure Plasma

The grains of durum wheat (Triticum durum Desf.) and achenes of common buckwheat (Fagopyrum esculentum Moench) were tested after treatment with two sources of non-thermal atmospheric pressure plasma (DCSBD, MSDBD) with different treatment times (0, 3, 5, 10, 20, 30, and 40 s). The effect of these treatments was monitored with regard to the seed surface diagnostics (water contact angle—WCA, chemical changes by Fourier transform infrared spectroscopy—FTIR); twenty parameters associated with germination and initial seed growth were monitored. A study of the wettability confirmed a decrease in WCA values indicating an increase in surface energy and hydrophilicity depending on the type of seed, plasma source, and treatment time. Surface analysis by attenuated total reflectance FTIR (ATR-FTIR) showed no obvious changes in the chemical bonds on the surface of the plasma-treated seeds, which confirms the non-destructive effect of the plasma on the chemical composition of the seed shell. A multivariate analysis of the data showed many positive trends (not statistically significant) in germination and initial growth parameters. The repeated results for germination rate and root/shoot dry matter ratio indicate the tendency of plants to invest in underground organs. Durum wheat required longer treatment times with non-thermal plasma (10 s, 20 s) for germination and early growth, whereas buckwheat required shorter times (5 s, 10 s). The responses of durum wheat grains to the two non-thermal plasma sources used were equal. In contrast, the responses of buckwheat achenes were more favorable to MSDBD treatment than to DCSBD

Plasma Treatment of Large-Area Polymer Substrates for the Enhanced Adhesion of UV–Digital Printing

UV–digital printing belongs to the commonly used method for custom large-area substrate decoration. Despite low surface energy and adhesion, transparent polymer materials, such as polymethylmethacrylate (PMMA) and polycarbonate (PC), represent an ideal substrate for such purposes. The diffuse coplanar surface barrier discharge (DCSBD) in a novel compact configuration was used for substrate activation to improve ink adhesion to the polymer surface. This industrially applicable version of DCSBD was prepared, tested, and successfully implemented for the UV–digital printing process. Furthermore, wettability and surface free energy measurement, X-ray photoelectron spectroscopy, atomic force, and scanning electron microscopy evaluated the surface chemistry and morphology changes. The changes in the adhesion of the surface and of ink were analyzed by a peel-force and a crosscut test, respectively. A short plasma treatment (1–5 s) enhanced the substrate’s properties of PMMA and PC while providing the pre-treatment suitable for further in-line UV–digital printing. Furthermore, we did not observe damage of or significant change in roughness affecting the substrate’s initial transparency

Cold atmospheric pressure plasma: simple and efficient strategy for preparation of poly(2-oxazoline)-based coatings designed for biomedical applications

Abstract Poly(2-oxazolines) (POx) are an attractive material of choice for biocompatible and bioactive coatings in medical applications. To prepare POx coatings, the plasma polymerization represents a fast and facile approach that is surface-independent. However, unfavorable factors of this method such as using the low-pressure regimes and noble gases, or poor control over the resulting surface chemistry limit its utilization. Here, we propose to overcome these drawbacks by using well-defined POx-based copolymers prepared by living cationic polymerization as a starting material. Chemically inert polytetrafluoroethylene (PTFE) is selected as a substrate due to its beneficial features for medical applications. The deposited POx layer is additionally post-treated by non-equilibrium plasma generated at atmospheric pressure. For this purpose, diffuse coplanar surface barrier discharge (DCSBD) is used as a source of “cold” homogeneous plasma, as it is operating at atmospheric pressure even in ambient air. Prepared POx coatings possess hydrophilic nature with an achieved water contact angle of 60°, which is noticeably lower in comparison to the initial value of 106° for raw PTFE. Moreover, the increased fibroblasts adhesion in comparison to raw PTFE is achieved, and the physical and biological properties of the POx-modified surfaces remain stable for 30 days