Forward jet-like event spin-dependent properties in polarized p+p collisions at s\sqrt{s}=200 GeV

The STAR collaboration has reported precision measurements on the transverse single spin asymmetries for the production of forward $\pi^0$ mesons from polarized proton collisions at $\sqrt{s} =\,$200 GeV. To disentangle the contributions to forward asymmetries, one has to look beyond inclusive $\pi^0$ production to the production of forward jets or direct photons. Present forward detector capabilities are not well matched to the complete reconstruction of forward jets, but do have sufficient acceptance for "jet-like" events. "Jet-like" events are the clustered response of an electromagnetic calorimeter that is primarily sensitive to incident photons, electrons and positrons. During the RHIC running in the year 2006, STAR with the Forward Pion Detector (FPD++) in place collected 6.8 pb$^{-1}$ of data with an average polarization of 60%. FPD++ was a modular detector prototype of the Forward Meson Spectrometer (FMS) that consisted of two detectors placed symmetrically with respect to the beam line at a distance of 7.4 m from the interaction point. Readout of the FPD++ was triggered when the sum of energies in the central module of the calorimeter used for $\pi^0$ measurements was larger than a threshold. This trigger minimizes the bias for "jet-like" events, making it appropriate to disentangling contributions to the forward transverse spin asymmetries. We report on the status of the analysis.Comment: 5 pages, 6 figures, SPIN10 conference (Juelich, Germany, 2010

Investigation and bending limits definition for tubular stabilizer bars

Predkladaná diplomová práca sa zaoberá ohýbaním rúrok ako podprocesom výroby stabilizačnej tyče automobilu. Hlavným cieľom práce je objasniť vplyv nastavovaných procesných parametrov ohybu na výsledný geometrický tvar výrobku a jeho vlastnosti. Práca obsahuje teoretický rozbor vybranej metódy ohýbania rúrok, popis vznikajúcich defektov a možnosti ich odstránenia. Následne je prevedený popis ohýbacieho zariadenia špeciálne navrhnutého na výrobu stabilizátorov. V rámci praktickej časti sú prevedené experimenty na objasnenie vplyvu jednotlivých parametrov na výsledný ohyb.Submitted master’s thesis deals with rotary draw bending of tubes as a subprocess of automobile’s stabilizer bar production. The main goal of the thesis is to clarify the influence of the process parameters of the bend on the resulting shape and properties of the product. Submitted thesis includes theoretical description of the chosen tube bending technology, description of defects and possibilities of their removal. The description of the bending machine used for stabilizer bars production is done afterwards. Practical part of the thesis includes experiments clarifying influence of parameters on the resulting shape of the stabilizer bar.

Variants of ring rolling methods

Predložená práca vypracovaná v rámci bakalárskeho štúdia B23390-00 Strojní inženýrství sa zaoberá technológiou valcovania prstencov. V rešerši sú popísané princípy technológie valcovania prstencov, prehľad tvarových skupín vyrábaných dielcov za tepla a za studena a prehľad nástrojov a strojov používaných v rámci technológie.The submitted work developed within the bachelor study B23390-00 Mechanical engineering deals with technology of ring rolling. Principles of the technology of ring rolling, list of various shapes produced by hot and cold ring rolling and summary of machines and tools used within this technology are described in this recherché.

Data sorting

Ovaj rad prikazuje jedno od rješenja problema sortiranja podataka u jednodimenzionalnom polju (nizu) elemenata. U praksi se često pojavljuje potreba za sortiranjem podataka te se zbog toga traži što efikasniji i brži algoritam. U ovom radu detaljno je prikazan jedan od najboljih - merge-sort algoritam. Napravljene su i praktične izvedbe algoritama za sortiranje koje su testirane na različitim skupovima podataka.In this paper one solution of the problem of sorting an one-dimensional vector (array) of data is shown in this paper. A need for data sorting very often arises in the practice and therefore we are constantly searching for more efficient and faster sorting algorithms. One of the best sorting algorithms -merge-sort is shown in this paper in detail. We made two of sorting algorithms and tested them on different types of data

Amphibian decline and their protection in Croatia

Vodozemci su među najugroženijim životinjama na Zemlji. Oko jedna trećina danas poznatih vrsta ozbiljno je ugrožena i vrlo je moguće da neće preživjeti ovo stoljeće. U zadnjih 30 godina nestalo je oko 200 vrsta, od kojih su mnoge bile jedinstvene. Premda je u istraživanje ove zabrinjavajuće pojave uložen popriličan trud, vrijeme i novac, još uvijek postoji mnogo više pitanja nego odgovora u vezi nestajanja vodozemaca. Čini se da je za postizanje rezultata potrebno dugotrajno, sustavno i široko praćenje stanja populacija vodozemaca. Od lokalnih uzročnika nestajanja vodozemaca svakako je značajan nestanak, promjena i fragmentacija staništa, unošenje novih predatora i kompetitora, zagađenje i pretjerano iskorištavanje u komercijalne svrhe. U globalne uzročnike ubrajaju se povišenje temperature uslijed globalnog zagrijavanja, kao i druge posljedice istog, kao npr. regionalne promjene u vodnom režimu (posebice povećana učestalost suša), isušivanje tla, produženje sušnih razdoblja, i sve veća varijabilnost količine oborina. Kao uzroci navode se još kisele kiše, deforestacija i pojačano UV-B zračenje. Svi ovi čimbenici mogu djelovati direktno izazivajući smrt ili indirektno uzrokujući stres. U Hrvatskoj ne postoji sustavno praćenje populacija vodozemaca. Trebalo bi organizirati široku mrežu aktivnosti raznih lokalnih udruga, koje bi koordinirala ekipa stručnjaka. Time bi se dobili vrijedni podaci o stanju populacija u Hrvatskoj. U ovom trenutku ne možemo sa sigurnošću tvrditi da nestajanja nema, dok u svakom slučaju određeni rizični čimbenici postoje.Amphibians belong to one of the most critically endangered group of animals on planet Earth. About one third of the species are seriously in danger and it is possible that they will not survive this century. In the last 30 years about 200 species have disappeared and some of them were unique. A hard work, time and money were invested in the research of causes of amphibian decline but there are still more questions then the answers. It seems that we need long and systematic monitoring over populations of amphibians so they can provide some results. Local factors that cause disappearance of amphibians are: changed or lost habitat, its fragmentation, import of the predators and competitors, pollution and huge exploitation. Global factors are: temperature rising as a consequence of global warming, and other causes such as regional changes in water heights (especially rising frequency of dry periods), soil melioration and variability of rain seasons. There are also acid rains, deforestation and high UV – B radiation. All of these factors can act directly causing death or indirectly causing stress. In Croatia does not exist systematic monitoring over populations of amphibians. We should organise activities of local groups (such as monitoring), who would be under surveillance of scientist. In this way we can get important information about populations that live here. In this moment we can not discuss about amphibian decline because there is no data evidence, but there are some factors of risk