pi-Xi correlations in d+Au and Au+Au collisions at STAR

Qualitative comparison of source sizes from pi-Xi correlations analyses in d+Au and Au+Au collisions at sqrt(s_NN)=200G GeV and sqrt(s_NN)=62 GeV is presented. For the most central Au+Au collisions at sqrt(s_NN)=200 GeV we report first quantitative results concerning size of the pi-Xi source and relative shift of the average emission points between pi and Xi showing that the homogeneity region of Xi source is smaller then that of pion and significantly shifted in the transverse direction.Comment: prepared for the poster-session proceedings of the 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (QM2006

Processes of contact damage bearing materials

Obsahem této bakalářské práce je pojednání o procesech kontaktního poškození ložisek a jejich materiálů, rozbor jednotlivých druhů degradace materiálu, kontaktní únavová pevnost a způsoby jejího měření. Závěrem práce jsou rozebrány směry budoucího vývoje v optimalizaci ložisek.The focus of this bachelor’s thesis is treatise on processes of contact failures of bearings and theirs materials analyse type of degradation processes of material, contact fatigue strength and means of metering. In fine of bachelor’s thesis are given development of future tendencies in optimalization of bearings.

The bridge among buildings

Diplomová práce se zabývá návrhem vhodné nosné ocelové konstrukce lávky pro chodce. Lávka slouží k propojení dvou samostatných budov (budovy D a Z na Fakultě stavební Vysokého učení technického v Brně). Byly vypracovány čtyři varianty řešení nosné ocelové konstrukce. Výsledná varianta byla podrobně zpracována a bylo provedeno statické posouzení jednotlivých prvků a vybraných detailů. Hlavní nosnou konstrukcí této varianty jsou dva příhradové nosníky. Diagonály těchto nosníků jsou navrženy systémem táhel Macalloy 460. Mostovka lávky je ocelobetonová spřažená s příčníky. Lávka je navržena o jednom poli s převislým koncem. Délka pole je 34,8m, délka převislého konce 5,8m. Celková délka lávky je 40,6m. Šířka lávky je 2,8m. Šířka průchozího prostoru je 2m. Výška lávky nad terénem je 4,43m v místě osy místní komunikace. U budovy Z je lávka uložena na betonové opěře, u budovy D je uložena na ocelové rámové podpěře. Lávka je uložena na elastomerových ložiscích. Lávka je chráněna před povětrnostními vlivy. Opláštění lávky je navrženo systémem Wictec 60. Diplomová práce obsahuje také výkresovou dokumentaci navrženého řešení.This master's thesis deals with the designing of the appropriate supporting steel structure footbridge for pedestrians. The footbridge is used to connect two separate buildings (buildings D and Z at the Faculty of Civil Engineering Brno University of Technology). Four variants have been designed about solutions supporting steel structure. The final variant was prepared in detail and was carried out static assessment of the individual elements and selected details. The main supporting structure of this variant are two trusses. Diagonals of these trusses are designed linkage system of Macalloy 460. Bridge deck is designed of composite steel a concrete board with crossbars. The footbridge is designed as simple beam with an overhanging end. Length span is 34.8 m, length overhanging ends is 5.8 meters. The total length of the footbridge is 40.6 meters. Width of footbridge is 2.8 meters. Free width is 2 meters. In the cross point with the axis of local road is height of footbridge above ground 4.43 meters. Next to the building Z, there is a footbridge stored on a concrete support, near the building D, the footbridge is stored on a steel frame of support. The footbridge is deposited on elastomeric bearings. The footbridge is being protected from the weather. The sheating of the building is designed by Wictec 60 system. The master's thesis also contains drawing documentation of the proposed solution.

Design of multi-functional machining centre

První část diplomové práce pojednává o managementu rizik, legislativě a bezpečnosti, kterou musí obráběcí stroje splňovat, aby mohly být uvedeny na trh. Dále tato část obsahuje rozbor ochranných krytů, jelikož krytování je nedílnou součástí bezpečného stroje. Druhá část diplomové práce posuzuje bezpečnost multifunkčního obráběcího centra CNC EcoSMART 1-line. Na základě zjištěných rizik byly navrženy a zkonstruovány vnitřní i vnější kryty.The first part of the thesis deals with risk management, legislation and safety, the machine must meet in order to be placed on the market. This part contains an analysis of the guards, because the guards an integral part of safe machine. The second part of the thesis assesses the safety of multifunction machining center CNC EcoSmart 1-line. Based on the identified risks have been designed and built the inner and outer guards.

Setting up a STAR Tier 2 Site at Golias/Prague Farm

High Energy Nuclear Physics (HENP) collaborations' experience show that the computing resources available at a single site are often neither sufficient nor satisfy the need of remote collaborators. From latencies in the network connectivity to the lack of interactivity, work at distant computing centers is often inefficient. Having fully functional software stack on local resources is a strong enabler of science opportunities for any local group who can afford the time investment. Prague's heavy-ions group participating in STAR experiment at RHIC has been a strong advocate of local computing as the most efficient means of data processing and physics analyses. Tier 2 computing center was set up at a Regional Computing Center for Particle Physics called "Golias". We report on our experience in setting up a fully functional Tier 2 center and discuss the solutions chosen to address storage space and analysis issues and the impact on the farms overall functionality. This includes a locally built STAR analysis framework, integration with a local DPM system (a cost effective storage solution), the influence of the availability and quality of the network connection to Tier 0 via a dedicated CESNET/ESnet link and the development of light-weight yet fully automated data transfer tools allowing the movement of entire datasets from BNL (Tier 0) to Golias (Tier 2).Comment: To appear in proceedings of Computing in High Energy and Nuclear Physics 200

Multibosonové jevy na RHIC

Au-Au collisions at RHIC energies exhibit features suggesting that the system has undergone evolution through a stage of partonic matter. The hot and dense system created in the collision builds up substantial collectivity leading to rapid transverse expansion. In particular recent measurements show that Ξ and Ω baryons develop substantial elliptic flow. Properties of the induced flow strongly depend on whether the collectivity is achieved on partonic or hadronic level. Multi-strange baryons may be, due to their presumably small hadronic cross- sections, mainly sensitive to the early (possibly partonic) stage. The main objective of this thesis is to study femtoscopic π−Ξ correlations in Au+Au collisions at √ sNN =200 GeV and √ sNN =62 GeV recorded by the STAR experiment at RHIC. Measurements of momentum correlations of particles at small relative velocities are used to extract information about space-time extension of the particle-emitting source at the time of kinetic freeze-out. Non-identical particle measurements are sensitive not only to the size of the system, but also to an emission asymmetry between different particle species. Since this asymmetry may arise from the collective expansion and/or early decoupling of Ξ these measurements of π−Ξ correlations provide important test of the dynamics of..