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Attrition or dropout is the most severe missingness problem in longitudinal cohort study data where some participants do not show up for follow‐up examinations. Dropouts result in biased data and cause the reduction of 1ata set size. Moreover, they limit the power of statistical analysis and the validity of study findings. Visualization can play a strong role in analysing and displaying the missingness patterns. In this work, we present VIVID, a framework for the visual analysis of missing values in cohort study data. VIVID is inspired by discussions with epidemiologists and adds visual components to their current statistics‐based approaches. VIVID provides functions for exploration, imputation and validity check of imputations. The main focus of this paper is multiple imputation to fix the missing data. [ABSTRACT FROM AUTHOR]

Abstract: The discharge vessels of advanced metal halide lamps are made of polycrystalline alumina (PCA). Such metal halide lamps contain a salt mixture, which in part vaporize under operating conditions. Important constituents of the fillings are metal iodides and bromides such as TmX3, HoX3, DyX3, and NaX (X=I, Br). The understanding of the complex high temperature chemistry in such lamps is an important aspect of the development. The identification of volatile species present in the gas phase and the determination of valuable thermodynamic data for these species is the purpose of our investigations. The determination of thermodynamic data for gaseous species and condensed phases by the elucidation of vaporization processes is taken out by the use of high temperature mass spectrometry, which is the most versatile method for these studies. Corrosion attack of the discharge vessels made of translucent alumina is observed during lamp operation. This can limit their life time. An essential aspect of this corrosion attack is the gas phase transport of Al2O3 in the PCA discharge vessel from the hot part to the cold side. Vaporization experiments were carried out using Knudsen effusion mass spectrometry. The mass spectrometric studies showed the formation of the vapor species AlX3(g) as gaseous corrosion product formed by the reaction of lanthanide halides (LnX3) with Al2O3. The gaseous species AlO(g) and AlOX(g) were identified besides others on leaking iodine and bromine into the Knudsen cell filled with alumina lumps. [Copyright &y& Elsevier]

Abstract: The phase diagram of the quasi binary NaBr–DyBr3 system was determined by differential thermal analysis (DTA) applied to 27 samples covering the complete composition range of the system. The 3NaBr*DyBr3(s) compound is present in the solid-phase in addition to the pure component halides NaBr(s) and DyBr3(s). The DyBr3(s) and 3NaBr*DyBr3(s) phases showed a polymorphic transition at 1112 and at 733K, respectively. The {DyBr3(s)+3NaBr*DyBr3(s)} eutectic mixture melts at 709K giving a liquid of the molar composition x(NaBr)=0.62. The 3NaBr*DyBr3(s) phase melts peritectically at 765K. The phase diagram obtained in the present study virtually agrees with the calculated one available in literature. [Copyright &y& Elsevier]

Abstract: Conventional petroleum jet and diesel fuels, as well as alternative Fischer–Tropsch (FT) fuels and hydrotreated renewable jet (HRJ) fuels, contain high molecular weight lightly branched alkanes (i.e., methylalkanes) and straight chain alkanes (n-alkanes). Improving the combustion of these fuels in practical applications requires a fundamental understanding of large hydrocarbon combustion chemistry. This research project presents a detailed and reduced chemical kinetic mechanism for singly methylated iso-alkanes (i.e., 2-methylalkanes) ranging from C7 to C20. The mechanism also includes an updated version of our previously published C8–C16 n-alkanes model. The complete detailed mechanism contains approximately 7200 species 31400 reactions. The proposed model is validated against new experimental data from a variety of fundamental combustion devices including premixed and non-premixed flames, perfectly stirred reactors and shock tubes. This new model is used to show how the presence of a methyl branch affects important combustion properties such as laminar flame propagation, ignition, and species formation. [Copyright &y& Elsevier]