The collaborative effect of ram pressure and merging on star formation and stripping fraction

Aims: We investigate the effect of ram pressure stripping (RPS) on simulations of merging pairs of gas-rich spiral galaxies. Our goal is to provide an estimate of the combined effect of merging and RPS on stripping efficiency and star formation rate. Methods: We make use of the combined N-body/hydrodynamic code GADGET-2. In our simulations, we vary mass ratios between 1:4 and 1:8 in a binary merger. We sample different geometric configurations of the merging systems (edge-on and face-on mergers, different impact parameters). Furthermore, we vary the properties of the intracluster medium (ICM) in rough steps: The speed of the merging system relative to the ICM between 500 and 1000 km/s, the ICM density between $10^{-29}$ and $10^{-27}$ g/cm$^3$, and the ICM direction relative to the mergers' orbital plane. Ram pressure is kept constant within a simulation time period, as is the ICM temperature of $10^7$ K. Each simulation in the ICM is compared to simulations of the merger in vacuum and the non-merging galaxies with acting ram pressure. Results: Averaged over the simulation time (1 Gyr) the merging pairs show a negligible 5% enhancement in SFR, when compared to single galaxies under the same environmental conditions. The SFRs peak at the time of the galaxies first fly-through. There, our simulations show SFRs of up to 20 M$_{\odot}$/yr (compared to 3 M$_{\odot}$/yr of the non-merging galaxies in vacuum). In the most extreme case, this constitutes a short-term ($<50$ Myr) SFR increase of 50% over the non-merging galaxies experiencing ram pressure. The wake of merging galaxies in the ICM typically has a third to half the star mass seen in the non-merging galaxies and 5% to 10 % less gas mass. The joint effect of RPS and merging, according to our simulations, is not significantly different from pure ram pressure effects.Comment: 12 pages, 13 figures, 3 tables, A&

Large-scale mass distribution in the Illustris simulation

Observations at low redshifts thus far fail to account for all of the baryons expected in the Universe according to cosmological constraints. A large fraction of the baryons presumably resides in a thin and warm-hot medium between the galaxies, where they are difficult to observe due to their low densities and high temperatures. Cosmological simulations of structure formation can be used to verify this picture and provide quantitative predictions for the distribution of mass in different large-scale structure components. Here we study the distribution of baryons and dark matter at different epochs using data from the Illustris simulation. We identify regions of different dark matter density with the primary constituents of large-scale structure, allowing us to measure mass and volume of haloes, filaments and voids. At redshift zero, we find that 49 % of the dark matter and 23 % of the baryons are within haloes more massive than the resolution limit of $2\times 10^8$ M$_\odot$. The filaments of the cosmic web host a further 45 % of the dark matter and 46 % of the baryons. The remaining 31 % of the baryons reside in voids. The majority of these baryons have been transported there through active galactic nuclei feedback. We note that the feedback model of Illustris is too strong for heavy haloes, therefore it is likely that we are overestimating this amount. Categorizing the baryons according to their density and temperature, we find that 17.8 % of them are in a condensed state, 21.6 % are present as cold, diffuse gas, and 53.9 % are found in the state of a warm-hot intergalactic medium.Comment: 12 pages, 15 figure

Halide ion influence on the formation of nickel nanoparticles and their conversion into hollow nickel phosphide and sulphide nanocrystals

A dependence of the formation of tri-n-octylphosphine-capped Ni nanocrystals on the presence of halide ions during their synthesis is shown. For the application-oriented synthesis of Ni particles, this information can be crucial. Furthermore, Ni nanoparticles can be converted to nickel phosphide or sulphide by heating them up in the presence of a phosphorus or sulphur source, resulting in either solid or hollow nanocrystals, formed via the nanoscale Kirkendall effect, depending on the synthesis route. By adjusting the Ni crystallite size in the initial nanoparticles via the halide ion concentration the cavity size of the resulting hollow nanocrystals can be tuned, which is otherwise impossible to realise for particles of a similar total diameter by using this process. The synthesised hollow Ni3S2 nanocrystals exhibit a much sharper localised surface plasmon resonance (LSPR) band than all previously presented particles of this material, which is known to show molar extinction coefficients at the LSPR maximum similar to Au. This narrow linewidth could be explained by the nanoparticles’ high crystallinity resulting from the Kirkendall process and is interesting for various possible optical applications such as surface-enhanced Raman spectroscopy owing to the low cost of the involved materials compared to the widely used noble metals

Mushroom Detection and Recognition in Natural Environment

Práce řeší problém detekce a klasifikace hub na fotografiích v přirozeném prostředí. K řešení jsem použil konvoluční neuronové sítě. Začátek práce je věnován teorii neuronových sítí. Dále je v práci řešena detekce hub a jejich klasifikace. S pomocí plně konvoluční neuronové sítě je vyřešen i problém lokalizace hub. Výsledky naučených neuronových sítí jsou analyzovány.In this thesis is handled the problem of mushroom detection and recognition in natural environment. Convolutional neural networks are used. The beginning of this thesis is dedicated to the theory of neural networks. Further is solved the problem of object detection and classification. Using neural network trained for classification is solved also the task of localization. Results of trained CNNs are analised.

Processor Models Creation Using ADL Language

Goal of this bachelor thesis is to create instruction level models of two processors Tensilica Xtensa and Sparc Leon. Models were implemented in CodAL language. Development, simulation and testing took place in Codasip Studio, an IDE developed by Codasip company. Application Specific Instruction-Set Processors can be implemented from scratch or already implemented processor can be modified to meet needs of specific aplication. My models will be added to portfolio of Codasip company to be used and modified by the user of Codasip Studio. Result of this work are tested models of these two processors. Simulator, assembler and C language compiler of these processors can be generated. Models were compared by several Benchmark tests and results were analyzed

The general execution of a construction project from the perspective of a joint venture and the influence of the cartel law

Abweichender Titel laut Übersetzung der Verfasserin/des VerfassersZsfassung in engl. SpracheVon der Projektidee bis zur Fertigstellung eines Bauwerks bedarf es unter anderem an Kreativität, Ingenieurskunst, Zeit, Kosten, Geräten, Personal und Material. Manche Projekte erfordern aber ein so großes Maß an Ressourcen, dass sich Einzelunternehmen des Öfteren zusammenschließen und ein gemeinsames Angebot abgeben. Kommt es zum Zuschlag, wickeln diese Partnerfirmen das betreffende Projekt als Arbeitsgemeinschaft ab und haften für den Bauerfolg solidarisch. Der Beginn der Arbeit behandelt die allgemeinen Grundlagen, in denen neben der Definition und den Merkmalen auch die Formen von Arbeitsgemeinschaften erläutert sind. Es folgen darin auch Beschreibungen der Vor- und Nachteile von Arbeitsgemeinschaften aus der Sicht von Auftragnehmern und Auftraggebern sowie eine Auflistung der Besonderheiten des Marktes in der Bauwirtschaft. Die anschließenden Kapitel erläutern die verschiedenen Projektphasen bei der Bauabwicklung sowie die dabei zu beachtenden Besonderheiten. Im Hauptkapitel dieser Arbeit werden das Kartellrecht sowie dessen Einfluss auf Arbeitsgemeinschaften erörtert. Grundsätzlich versteht man unter einem kartellrechtlichen Verstoß eine verursachte Wettbewerbsbeschränkung durch Vereinbarungen zwischen Unternehmen, Beschlüsse von Unternehmensvereinigungen und aufeinander abgestimmte Verhaltensweisen. Schließen sich demnach zu mächtige Unternehmen zusammen, liegt der Verdacht eines Kartellverstoßes nahe. Es wird erklärt, wo die Grenze an Marktmacht liegt, unter welcher man keine kartellrechtlichen Bestimmungen verletzt. Auch die Gegenüberstellung von nationalem und europäischem Kartellrecht sowie deren Gemeinsamkeiten und Differenzen unterliegen einer ausführlichen Erläuterung. Zusätzlich werden neben den kartellrechtlichen Gesetzestexten auch die wesentlichen wettbewerbsregelnden Komponenten und deren Zusammenhang behandelt. Besonders die wettbewerbsrechtliche Beurteilung, die jede Arbeitsgemeinschaft für sich zu erfüllen hat, wird in dieser Arbeit äußerst genau beschrieben. Dazu entwickelte der Autor ein Ablaufdiagramm, das dieses Beurteilungsprozedere grafisch darstellt und eine Übersicht über das komplexe Thema bietet. Abschließend findet eine Auswertung von persönlich geführten Interviews mit Spezialisten aus der Bauwirtschaft statt. Dazu nahmen drei Auftragnehmer und drei Auftraggeber Stellung zu Arbeitsgemeinschaften in genereller Hinsicht und zu deren kartellrechtlichen Bezug.Between a construction idea and its implementation creativity, engeneering skills, time, money, devices, human ressources, material, etc. are required. Some projects cannot be handled by all contractors because of their immense volume. The only possibility for some contractors to be part of the competition is establishing a bidding consortium. Thereby some construction companies are combined to submit a joint. In case of winning the competition, the companies sign a contract to operate as a joint venture and to be liable solidary. At the beginning of this master thesis, a chapter presents general information about joint ventures and contains details on their characteristics and their forms of their occurance as well as the definition of joint ventures. The advantages and disadvantages of joint ventures for contractors and employers are also listed and the characteristics of bidding markets in the construction industry are described. The following chapters of this master thesis deal with the phases of a project and their specific regulations concerning to joint ventures. The main chapter of this master thesis discusses the cartel law and its influence on joint ventures. This topic is already briefly mentioned in the first part of this master thesis, when the process planing is discussed. Breach of the cartel law generally means a created restraint of competition caused by all agreements between undertakings, decisions by associations of undertakings and concerted practices. According to this, joint ventures, being powerful contractors, are suspected to break the cartel law because of their big market influence. How this border line of allowed market influence is defined will be answered in this thesis, as well as: -Do joint ventures always constrain the competition because of the induced reduction of the amount of bidders?-. Additionally, a comparison of the national and the European law and their commonalities as well as their differences forms an important part of this master thesis. Furthermore, the wording of the cartel law as well as the fundamental components to regulate the competition and their relationship will be presented. The competitive evaluation of the cartel law referring to the respective joint venture that has to be completed by every joint venture before submitting an offer is described in detail. In order to reach a clearer overview about this complex topic, the author created a flow diagramm. This master thesis concludes with an analysis of interviews with experts from the construction industry. Three contractors and three employers where asked about their opinion on joint ventures and the influence of the cartel law as it applies to them.15

Mushroom Detection and Recognition in Natural Environment

In this thesis is handled the problem of mushroom detection and recognition in natural environment. Convolutional neural networks are used. The beginning of this thesis is dedicated to the theory of neural networks. Further is solved the problem of object detection and classification. Using neural network trained for classification is solved also the task of localization. Results of trained CNNs are analised