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Diese Diplomarbeit beschäftigt sich sowohl mit der Akquisition, der Verwaltung und der winkelabhängigen, spektralen Reflexionsfunktion BRDF (Bidirectional Reflectance Distribution Function) und BTFs (Bidirection Texture Functions) von einigen ausgewählten realistischen Materialoberflächen bei fester Beleuchtung, als auch der Generierung der BTFs aus vorhandenen BRDFs und BTFs und der Anwendung der Beschreibung von Oberflächen mittels BRDFs und BTFs bei Erzeugungen von 3D-Szenen. Im Rahmen dieser Diplomarbeit werden Konzepte für eine effektivere Nutzung von BTFs in der photorealistischen Bilderzeugung entwickelt und prototypisch umgesetzt. Der Fokus liegt dabei auf einer vereinfachten Synthese von BTFs aus vorhandenen BRDF- und BTF-Daten, sowie in einer effizienten Nutzbarmachung dieser Informationen für Rendering-Prozesse.
Genomic sequencing and analysis of worldwide skipper butterfly (Lepidoptera: Hesperiidae) fauna points to imperfections in their current classification. Some tribes, subtribes and genera as they are circumscribed today are not monophyletic. Rationalizing genomic results from the perspective of phenotypic characters suggests two new tribes, two new subtribes and 50 new genera that are named here: Ceratrichiini Grishin, trib. n., Gretnini Grishin, trib. n., Falgina Grishin, subtr. n., Apaustina Grishin, subtr. n., Flattoides Grishin, gen. n., Aurivittia Grishin, gen. n., Viuria Grishin, gen. n., Clytius Grishin, gen. n., Incisus Grishin, gen. n., Perus Grishin, gen. n., Livida Grishin, gen. n., Festivia Grishin, gen. n., Hoodus Grishin, gen. n., Anaxas Grishin, gen. n., Chiothion Grishin, gen. n., Crenda Grishin, gen. n., Santa Grishin, gen. n., Canesia Grishin, gen. n., Bralus Grishin, gen. n., Ladda Grishin, gen. n., Willema Grishin, gen. n., Argemma Grishin, gen. n., Nervia Grishin, gen. n., Dotta Grishin, gen. n., Lissia Grishin, gen. n., Xanthonymus Grishin, gen. n., Cerba Grishin, gen. n., Avestia Grishin, gen. n., Zetka Grishin, gen. n., Turmosa Grishin, gen. n., Mielkeus Grishin, gen. n., Coolus Grishin, gen. n., Daron Grishin, gen. n., Barrolla Grishin, gen. n., Brownus Grishin, gen. n., Tava Grishin, gen. n., Rigga Grishin, gen. n., Haza Grishin, gen. n., Dubia Grishin, gen. n., Pares Grishin, gen. n., Chitta Grishin, gen. n., Artonia Grishin, gen. n., Lurida Grishin, gen. n., Corra Grishin, gen. n., Fidius Grishin, gen. n., Veadda Grishin, gen. n., Tricrista Grishin, gen. n., Viridina Grishin, gen. n., Alychna Grishin, gen. n., Ralis Grishin, gen. n., Testia Grishin, gen. n., Buzella Grishin, gen. n., Vernia Grishin, gen. n., and Lon Grishin, gen. n. In addition, the following taxonomic changes are suggested. Prada Evans is transferred from Hesperiinae to Trapezitinae. Echelatus Godman and Salvin, Systaspes Weeks, and Oenides Mabille are removed from synonymy and are treated as valid genera. The following genera are new junior subjective synonyms: Tosta Evans of Eantis Boisduval; Turmada Evans of Neoxeniades Hayward, Arita Evans of Tigasis Godman, and Alera Mabille of Perichares Scudder. Eantis pallida (R. Felder) (not Achlyodes Hübner), Gindanes kelso (Evans) (not Onenses Godman and Salvin), Isoteinon abjecta (Snellen) (not Astictopterus C. and R. Felder), Neoxeniades ethoda (Hewitson) (not Xeniades Godman), Moeris anna (Mabille) (not Vidius Evans), and Molo pelta Evans (not Lychnuchus Hübner) are new genus-species combinations. The following are species-level taxa: Livida assecla (Mabille) (not a subspecies of Livida grandis (Mabille), formerly Pythonides Hübner) and Alychna zenus (E. Bell) (not a junior subjective synonym of Alychna exclamationis (Mabille), formerly Psoralis Mabille); and Barrolla molla E. Bell (formerly Vacerra Godman) is a junior subjective synonym of Barrolla barroni Evans (formerly Paratrytone Godman). All these changes to taxonomic status of names are propagated to all names currently treated as subspecies (for species), subgenera (for genera) and synonyms of these taxa. Finally, taxa not mentioned in this work are considered to remain at the ranks and in taxonomic groups they have been previously assigned to.
Using 10.1 × 109 J/ψ events produced by the Beijing Electron Positron Collider (BEPCII) at a center-of-mass energy √s = 3.097 GeV and collected with the BESIII detector, we present a search for the rare semi-leptonic decay J/ψ → D−e+νe + c.c. No excess of signal above background is observed, and an upper limit on the branching fraction ℬ(J/ψ → D−e+νe + c. c.) < 7.1 × 10−8 is obtained at 90% confidence level. This is an improvement of more than two orders of magnitude over the previous best limit.
The process e+e−→ϕη is studied at 22 center-of-mass energy points (√s) between 2.00 and 3.08 GeV using 715 pb−1 of data collected with the BESIII detector. The measured Born cross section of e+e−→ϕη is found to be consistent with BABAR measurements, but with improved precision. A resonant structure around 2.175 GeV is observed with a significance of 6.9σ with mass (2163.5±6.2±3.0) MeV/c2 and width (31.1+21.1−11.6±1.1) MeV, where the first uncertainties are statistical and the second are systematic.
We measure the inclusive semielectronic decay branching fraction of the D+s meson. A double-tag technique is applied to e+e− annihilation data collected by the BESIII experiment at the BEPCII collider, operating in the center-of-mass energy range 4.178–4.230 GeV. We select positrons fromD+s→Xe+νe with momenta greater than 200 MeV/c and determine the laboratory momentum spectrum, accounting for the effects of detector efficiency and resolution. The total positron yield and semielectronic branching fraction are determined by extrapolating this spectrum below the momentum cutoff. We measure the D+s semielectronic branching fraction to be(6.30±0.13(stat.)±0.09(syst.)±0.04(ext.))%, showing no evidence for unobserved exclusive semielectronic modes. We combine this result with external data taken from literature to determine the ratio of the D+s and D0 semielectronic widths, Γ(D+s→Xe+νe)Γ(D0→Xe+νe)=0.790±0.016(stat.)±0.011(syst.)±0.016(ext.). Our results are consistent with and more precise than previous measurements.
Relative fractions and phases of the intermediate decays are determined. With the detection efficiency estimated by the results of the amplitude analysis, the branching fraction of Dþ s → K−Kþπþπ0 decay is measured to be ð5.42 0.10stat 0.17systÞ%.
Using data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.178 to 4.600 GeV, we study the process eþe− → π0Xð3872Þγ and search for Zcð4020Þ0 → Xð3872Þγ. We find no significant signal and set upper limits on σðeþe− → π0Xð3872ÞγÞ · BðXð3872Þ → πþπ−J=ψÞ and σðeþe− → π0Zcð4020Þ0Þ · BðZcð4020Þ0 → Xð3872ÞγÞ · BðXð3872Þ → πþπ−J=ψÞ for each energy point at 90% confidence level, which is of the order of several tenths pb.
Based on an e+e− collision data sample corresponding to an integrated luminosity of 2.93 fb−1 collected with the BESIII detector at √s=3.773 GeV, the first amplitude analysis of the singly Cabibbo-suppressed decay D+→K+K0Sπ0 is performed. From the amplitude analysis, the K∗(892)+K0S component is found to be dominant with a fraction of (57.1±2.6±4.2)%, where the first uncertainty is statistical and the second systematic. In combination with the absolute branching fraction B(D+→K+K0Sπ0) measured by BESIII, we obtain B(D+→K∗(892)+K0S)=(8.69±0.40±0.64±0.51)×10−3, where the third uncertainty is due to the branching fraction B(D+→K+K0Sπ0). The precision of this result is significantly improved compared to the previous measurement. This result also differs from most of theoretical predictions by about 4σ, which may help to improve the understanding of the dynamics behind.
The electromagnetic process is studied with the initial-state-radiation technique using 7.5 fb−1 of data collected by the BESIII experiment at seven energy points from 3.773 to 4.600 GeV. The Born cross section and the effective form factor of the proton are measured from the production threshold to 3.0 GeV/ using the invariant-mass spectrum. The ratio of electric and magnetic form factors of the proton is determined from the analysis of the proton-helicity angular distribution.
By analyzing 6.32 fb − 1 of e+ e− annihilation data collected at the center-of-mass energies between 4.178 and 4.226 GeV with the BESIII detector, we determine the branching fraction of the leptonic decay D + s → τ + ντ, with τ+ → π + π0¯ντ, to be B D + s → τ + ν τ = (5.29 ± 0.25 stat ± 0.20 syst) %. We estimate the product of the Cabibbo-Kobayashi-Maskawa matrix element |Vcs|and the D + s decay constant f D + s to be f D + s|Vcs| = (244.8 ± 5.8 stat ± 4.8syst) MeV, using the known values of the τ + and D + s masses as well as the D + s lifetime, together with our branching fraction measurement. Combining the value of |Vcs| obtained from a global fit in the standard model and f D + s from lattice quantum chromodynamics, we obtain f D + s = (251.6 ± 5.9 stat ± 4.9syst) MeV and |Vcs| = 0.980 ± 0.023 stat ± 0.019 syst. Using the branching fraction of B D + s → μ + νμ = (5.35±0.21)×10−3, we obtain the ratio of the branching fractions B D + s → τ + ντ/B D +s → μ+νμ = 9.89±0.71, which is consistent with the standard model prediction of lepton flavor universality.