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Celostni pristop k razločevanju naravnih in antropogenih geokemičnih anomalij v tleh na rudarskih območjih
No full textGeochemical studies of soils are essential part of every mineral exploration program. Since easily accessible mineral deposits have mostly been mined out and new ore deposits are becoming harder to find, to supply raw materials that our civilization needs exploration geologists are frequently re-exploring old mine areas to find new ore bodies in the vicinity of previous mine workings. Ore prospectors working on brownfield areas are often dealing with the problem of identifying true sources for enrichmentsif geochemical anomalies are a result of manmade activities, such as emissions from mining or metallurgy, or they are associated with natural, ore-forming processes. The presented study utilised and tested geochemical methods to distinguish between man-made and natural enrichments in soils on three different areas. Elemental compositions of topsoil and subsoil samples collected from 249 sampling locations across the territory of Slovenia were used to determine the sources of geochemical anomalies on a national-wide scale, which could help identify potential exploration target areas. The results of data analyses indicated that lithology significantly affects the elemental composition of overlaying soils. The calculations of enrichment ratios showed that Ti levels are higher in soils on top of metamorphic and igneous rocks, Ni levels are more abundant on marlstones, while Ca is more prevalent in soils overlying carbonates. Anthropogenic activities, such as mining, ore processing, etc. can enrich soils with various heavy metals like Pb, Cu, Zn, and Hg and can remain in the affected soil for a long time. To investigate possible sources for elemental enrichments at mining sites, soil samples from profiles were analysed at the three significant Slovenian historical mine sites, Mežica, Idrija, Litija. The results of elemental analyse of soil samples from control profiles which were only affected by metal-enriched dust from smelters indicated that levels of certain metals decrease with depth, while profiles, excavated directly above natural mineralisation do not show this decreasing trend. As supplementary methods for the determination of sources of enrichments, the following methods were appliedX-ray powder diffraction analyses, Scanning Electron Microscopy, and analyses of isotopes. Isotopic analyses revealed that some soil samples collected from lower layers of profiles situated above mine workings have a similar isotopic fingerprint as ore samples from this orebody, indicating geochemical anomalies of these soils could be due to geogenic processes. In contrast, soil samples collected from upper layers of profiles above mine workings showed a similar isotopic fingerprint as attic dust samples, confirming that these soils have been enriched with particles from the nearby smelters which were deposited in the upper soil layers. While XRD analyses was employed to determine mineralogical composition of soils, due to small quantities of metal particles, EDS method was used to identify minerology of individual grains, which are carriers of metals. SEM/EDS observations revealed that soil samples with similar isotopic ratios as ore samples contain metal particles characterised by simple elemental compositions and well-defined crystal structures, indicating they were formed by natural processes. In contrast, surface soils with similar isotopic ratios as attic dust samples from houses near the old Žerjav smelter, contain metal particles that have a more complex elemental composition and complex grain morphologies, such as spherical shapes, voids, and gel-like textures. This suggests that metal particles in these cases were exposed to high-temperature processes that are typical for ore-processing activities. This study concluded that by utilising a variety of different methods, such as ICP-MS, SEM/EDS, and isotopic analyses, it is possible to differentiate between natural and anthropogenic sources of geochemical anomalies on mine sites
An unexpected game
No full textV diplomski nalogi sem predstavila svoj kratki igrani film Nepričakovana igra. Žanrsko film opredeljujem kot srhljivko in dramo, saj se zgodba osredotoča na šaljivost glavnega lika Matica, ki se ne zaveda, kako lahko njegove potegavščine vplivajo na druge. Za prikaz počutja glavnega lika, manipulativnosti njegovih čustev in njegovega dvoma o resničnosti dogajanja, sem se poslužila različnih tehnik montaže. Zgodba doseže vrh, ko Matica v gozdu napade Lovec. Lovec predstavlja preobrat v zgodbi in z njim sem stopnjevala napetost in pokazala, kako tanka je lahko meja med šalo in resnično nevarnostjo. Zgodba filma pokaže mejo med zabavo in resničnostjo ter opozori na posledice nepremišljenih dejanj.
V diplomski nalogi sem analizirala slog montaže filmov drugih režiserjev. Primerjala sem tudi montažne sloge teh filmov z montažnim slogom svojega kratkega igranega filma, saj menim, da imajo nekatere skupne lastnosti. Podrobneje sem se osredotočila na tiste dele filmov, ki prikazujejo pregone. Vzdušje je v mojem filmu na začetku šaljivo, umirjeno in preprosto, vrh pa dogajanje doseže pri pregonu, ko Matica preganja Lovec.In my thesis, I present my short feature film An Unexpected Game. The film falls within the horror/drama genre, as the story focuses on the humor of the main character Matic, who is unaware of how it can affect others. To show the main character’s feelings, the manipulativeness of his emotion and his doubt about the reality of the events, I used various editing techniques. The story reaches its climax when Matic is attacked by a Hunter in the forest. The Hunter represents a turning point in the story and I used him to increase the tension and show how thin the line between a joke and real danger can be. The film\u27s story shows the line between fun and reality and warns about the recklessness of actions.
In the written part of my thesis, I analyze the editing style of selected films by other directors. I also compare the editing styles of these films with the editing style of my short feature film, as I believe that they have some common features. I focus on the parts of the films that depict the chase. The atmosphere of my film is humorous, calm, and simple at the beginning. It reaches its peak during the chase, when Matic is being chased by the hunter
A two step chaos-based 3D model encryption
No full textAugmented and virtual reality, game designing, medicine, medical engineering, and many other fields all revolve around 3D models. This is because 3D models have superior visual information than digital images. However, in recent years the advancements in digital image encryption are more rapid than in 3D model encryption. As such, more study on 3D model encryption is deemed necessary. In this paper, a new 3D model chaos-based encryption scheme is suggested based on a shuffling process on the vertices and faces that compose the 3D object and a modulation on the vertex coordinates. The effectiveness of the proposed encryption technique is then verified through the distribution of occupied position analysis, peak signal to noise ratio, structural similarity index and correlation coefficients
Rodriguez-Ayerbe, Pedro (F-CNSUP2-SGS) Perturbations in polyhedral partitions and the related fragility of piecewise affine control. (English. English summary) Bull. Math. Soc. Sci. Math. Roumanie (N.S.) 61(109) (2018), no. 4, 439-452.
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Prospects for dark matter observations in dwarf spheroidal galaxies with the Cherenkov Telescope Array Observatory
No full textThe dwarf spheroidal galaxies (dSphs) orbiting the Milky Way are widely regarded as systems supported by velocity dispersion against self-gravity, and as prime targets for the search for indirect dark matter (DM) signatures in the GeV-to-TeV gamma-ray range owing to their lack of astrophysical gamma-ray background. We present forecasts of the sensitivity of the forthcoming Cherenkov Telescope Array Observatory (CTAO) to annihilating or decaying DM signals in these targets. An original selection of candidates is performed from the current catalogue of known objects, including both classical and ultrafaint dSphs. For each, the expected DM content is derived using the most comprehensive photometric and spectroscopic data available, within a consistent framework of analysis. This approach enables the derivation of novel astrophysical factor profiles for indirect DM searches, which are compared with results from the literature. From an initial sample of 64 dSphs, eight promising targets are identified – Draco I, Coma Berenices, Ursa Major II, Ursa Minor, and Willman 1 in the North, Reticulum II, Sculptor, and Sagittarius II in the South – for which different DM density models yield consistent expectations, leading to robust predictions. CTAO is expected to provide the strongest limits above ~10 TeV, reaching velocity-averaged annihilation cross sections of ~5times 10^{26}cm^3s^{-1} and decay lifetimes up to ~10^{26}s for combined limits. The dominant uncertainties arise from the imprecise determination of the DM content, particularly for ultrafaint dSphs. Observation strategies are proposed that optimize either deep exposures of the best candidates or diversified target selections