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In the field of mineral resources extraction, one main challenge is to meet production targets in terms of geometallurgical properties. These properties influence the processing of the ore and are often represented in resource modeling by coregionalized variables with a complex relationship between them. Valuable data are available about geometalurgical properties and their interaction with the beneficiation process given sensor technologies during production monitoring. The aim of this research is to update resource models as new observations become available. A popular method for updating is the ensemble Kalman filter. This method relies on Gaussian assumptions and uses a set of realizations of the simulated models to derive sample covariances that can propagate the uncertainty between real observations and simulated ones. Hence, the relationship among variables has a compositional nature, such that updating these models while keeping the compositional constraints is a practical requirement in order to improve the accuracy of the updated models. This paper presents an updating framework for compositional data based on ensemble Kalman filter which allows us to work with compositions that are transformed into a multivariate Gaussian space by log-ratio transformation and flow anamorphosis. This flow anamorphosis, transforms the distribution of the variables to joint normality while reasonably keeping the dependencies between components. Furthermore, the positiveness of those variables, after updating the simulated models, is satisfied. The method is implemented in a bauxite deposit, demonstrating the performance of the proposed approach., Helmholtz-Zentrum Dresden - Rossendorf e. V. (4213)

Massive Open Online Courses, universally labelled as MOOCs, become more and more relevant in the era of digitalization of higher education. The availability of free education resources without access restrictions for a plenty of potential users has changed the learning market in a way unthinkable only few decades ago. This form of web-based education allows to track all the actions of the students, thus providing an information base to understand how students' behaviour can influence their performance. The paper proposes a structural equation model in the framework of the component-based approach to measure which are the main factors affecting students' performance (Partial Least Squares Path Modelling). The novelty of the approach is the simultaneous analysis of more than one factor that exerts an impact on the performance. The analysis is carried out on the log data of a course available on the edX MOOCs platform named FedericaX.

Comunicació presentada al Congrés Internacional de Joves Investigadors en Demografia, en el marc de la XXV Conferència Internacional de Població, IUSSP. Sessió 1: "Rapports sociaux de sexe et comportements démographiques". Tours, 18 de juliol de 2005. The main purpose of this paper is to produce cause-specific mortality projections from models that include non-demographic variables in its model formulation. Total mortality, lung cancer, heart disease and suicide are modelled separately for the period between the late 1970s/early 1980s to the second half of the 1990s for Western and Eastern Europe and men and women. Short-term projections are made to 2010. The models are also validated by comparing modelled with observed standardised death rates. Because of the time lag between exposure and health effect of a particular variable, which is often a matter of years, current observations for the independent variables were used for the projections or when predictions were necessary, the latest available value was held constant for the required years. The results for total mortality showed that in most Western European countries, the observed decline since the late 1970s is set to continue in the near future for men, but is likely to level off among women. The decline that has been observed in most Eastern European countries since the mid- to late 1990s is predicted to continue. En el artículo se realizan unas proyecciones por causa de muerte, basándose en aquellos modelos que en su formulación incluyan variables no demográficas. Se proyecta por separado la mortalidad total, la mortalidad por cáncer de pulmón, por causa cardiaca y por suicidio, para el período comprendido entre finales de la década de los setenta-principios de los ochenta y hasta la segunda mitad de la década de los noventa, para Europa Occidental y Europa del Este y por sexo. Las proyecciones a corto plazo se calculan para el 2010. Debido al transcurso del tiempo entre la exposición y el efecto sobre la salud de una variable concreta, para elaborar las proyecciones y, para las variables independientes, se han utilizado los datos más recientes, manteniéndolos constantes en todos los años. Los resultados para la mortalidad total muestran que en la mayoría de los países de Europa Occidental, la disminución observada desde finales de los años setenta parece mantenerse en los hombres, pero probablemente se estabilice entre las mujeres. Continuará también el descenso para la mayoría de países de Europa del Este. En l'article es realitzen unes projeccions per causa de mort, basant-se en aquells models que incloguin, en la seva formulació, variables no demogràfiques. La mortalitat total, la mortalitat per càncer de pulmó, la mortalitat per causa cardíaca i el suïcidi, es projecten per separat, pel període comprès entre finals dels anys setanta-principis dels vuitanta i fins a la segona meitat dels anys noranta, per Europa Occidental i Europa de l'Est i per sexe. Les projeccions a curt termini es calculen per a 2010. Degut al pas del temps entre l'exposició i l'efecte sobre la salut d'una variable particular, per elaborar les projeccions i, pel que fa a les variables independents, s'han emprat les dades més recents, mantenint-les constants en tots els anys. Els resultats per a la mortalitat total mostren que en la majoria dels països d'Europa Occidental, la disminució observada des de finals dels anys setanta es mantindrà pels homes però probablement s'estabilitzarà en les dones. Continuarà també el descens en la majoria de països d'Europa de l'Est. Le propos principal de ce travail est de fournir des projections de mortalité par cause du décès, en utilisant une modélisation qui incluse des paramètres non démographiques. On projette de façon séparée la mortalité totale, celle due au cancer du poumon, aux maladies cardiaques et au suicide à partir de modèles basés sur les données d'observation sur la période de la fin des années 1970-début des années 1980 jusqu'à la seconde moitié des années 1990, pour l'Europe occidentale et orientale, et par sexe. Les projections sont à court terme, à l'horizon 2010. Les modèles sont validés en comparant les indices de mortalité observés avec les standardisés. Du fait du décalage temporel entre période d'exposition au risque et effet sur la santé d'une variable particulière, ce qui souvent est une question de plusieurs années, les données des variables explicatives furent utilisées pour les projections jusqu'à la période actuelle, et leur valeur maintenue constante dans le futur. Les résultats pour la mortalité totale montrent que dans la majeure partie des pays d'Europe occidentale, la baisse observée depuis la fin des années 1970 continuera dans le futur proche pour les hommes, mais probablement s'interrompra ou se ralentira pour les femmes. La baisse de la mortalité dans les pays d'Europe de l'Est depuis la fin des années 1990 devrait se poursuivre dans les années à venir.

Microsimulation models are widely used to evaluate the potential effects of different policies on social indicators. Most microsimulation models in use operate on a national level, disregarding regional variations. We describe the construction of a national microsimulation model for Germany, accounting for local variations in each of the more than 10,000 communities in Germany. The database used and the mechanisms implementing the population dynamics are described. Finally, the further development of the database and microsimulation programs are outlined, which will contribute towards a research lab that will be made available to the wider scientific community., methods, data, analyses, Online First

The environmental impact during concrete manufacturing can be reduced by using less cement or using types of cement with high amounts of secondary cementitious materials (SCMs) and fillers. Fly ash from municipal solid waste incineration (MSWI) is an unused material, which could potentially be used as an SCM or filler. The applicability of MSWI fly ash samples in cement-based materials was investigated through an indirect determination based on the chemical composition, toxic metal content and particle size distribution of the samples. Furthermore, how the samples compared to each other and how representative the samples were for MSWI fly ash, in general, were investigated by multivariate modelling. MSWI fly ash samples were obtained from Denmark, Sweden and Greenland. Comparing the chemical composition of the MSWI fly ash samples with the chemical requirements for coal fly ash to be used in concrete, specified in EN 450-1 2012, indicated a low potential as SCMs. Additionally, the MSWI fly ash contained and leached more toxic metals than the allowed limits. The particle size distributions were larger than cement and indicated limited potential as filler. A principal component analysis showed that the obtained samples were chemically different materials compared to each other and would have different effects if used in cement-based materials. Additionally, the samples from Denmark were unrepresentative of MSWI fly ash, while the Greenlandic and Swedish samples were comparable to previously studied MSWI fly ash samples.

In recent decades, substantial efforts have been devoted in flood monitoring, prediction, and risk analysis for aiding flood event preparedness plans and mitigation measures. Introducing an initial framework of spatially probabilistic analysis of flood research, this study highlights an integrated statistical copula and satellite data-based approach to modelling the complex dependence structures between flood event characteristics, i.e., duration (D), volume (V) and peak (Q). The study uses Global daily satellite-based Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) (spatial resolution of ∼5 km) during 1981–2019 to derive a Standardized Antecedence Precipitation Index (SAPI) and its characteristics through a time-dependent reduction function for Myanmar. An advanced vine copula model was applied to model joint distributions between flood characteristics for each grid cell. The southwest (Rakhine, Bago, Yangon, and Ayeyarwady) and south (Kayin, Mon, and Tanintharyi) regions are found to be at high risk, with a probability of up to 40% of flood occurrence in August and September in the south (Kayin, Mon, and Tanintharyi) and southwest regions (Rakhine, Bago, Yangon, and Ayeyarwady). The results indicate a strong correlation among flood characteristics; however, their mean and standard deviation are spatially different. The findings reveal significant differences in the spatial patterns of the joint exceedance probability of flood event characteristics in different combined scenarios. The probability that duration, volume, and peak concurrently exceed 50th-quantile (median) values are about 60–70% in the regions along the administrative borders of Chin, Sagaing, Mandalay, Shan, Nay Pyi Taw, and Keyan. In the worst case and highest risk areas, the probability that duration, volume, and peak exceed the extreme values, i.e., the 90th-quantile, about 10–15% in the southwest of Sagaing, southeast of Chin, Nay Pyi Taw, Mon and areas around these states and up to 30% in the southeast of Dekkhinathiri township (Nay Pyi Taw). The proposed approach could improve the evaluation of exceedance probabilities used for flood early warning and risk assessment and management. The proposed framework is also applicable at larger scales (e.g., regions, continents and globally) and in different hydrological design events and for risk assessments (e.g., insurance).

Investing or trading in a country, whether domestic or foreign, involves some elements of risks and uncertainties depending upon its systemic, economic, financial, political, and business operating environments. Understanding the phenomenon of country risk is enormously vital for global investors in appraising risks versus opportunities of their global investment decisions. It is, therefore, necessary to evaluate countries and select the best and the most suitable one for the purpose of investment or business. Country risk analysis is both an art as well as science. Considering this, the present paper delineates numerous sources of country risk associated with business activities in a prospective country that may inauspiciously affect an initial investment, assets values, cash-flows or profits. It investigates theoretical linkages between country risk and country contestability. Based on systems thinking, structural equation modelling, and multivariate data analysis, this paper succinctly illustrates the theoretical scaffolding of Kanji-Chopra Country Risk Measurement System (KCCRMS). The conceptual notion of the phenomenon of country risk in the KCCRMS is holistic, multidimensional and multidisciplinary. The paper further divulges how critical country risk factors simultaneously intensify country risk in a multiplicative way or may interact producing reciprocal compensatory and attenuating effects. The KCCRMS’s structure, constructs, and relationships have been rigorously tested by means of data derived from various sources for an empirical analysis with special reference to Northern African economies namely Morocco, Algeria, Tunisia, Libya and Egypt. A country risk matrix has been constructed to illustrate the systemic risk, economic risk, political risk, financial risk and operating risk for each selected Northern African economy. Pathway analysis and sensitivity analysis on research questions have been performed for a detailed data analysis and interpretation. The paper constructs a composite country risk index for each country for the ratings of Northern African economies in terms of country risk and using the rating for investment decision making. Results from empirical analysis may be used to pinpoint the ways to minimise various risks of investing in these economies. - Investire o commerciare con un paese straniero, o nel proprio, coinvolge elementi di rischio e incertezze che dipendono dall’operatività sistemica, economica, finanziaria, politica e commerciale del paese stesso. La comprensione del fenomeno del rischio paese è vitale per gli investitori globali che devono valutare il rischio rispetto alle opportunità degli investimenti. Pertanto è necessario valutare i paesi e selezionare il migliore e più adatto allo scopo dell’investimento o del commercio. La valutazione del rischio paese è un’arte e insieme una scienza. Con questo presupposto questo studio delinea diverse fonti di rischio associate alle attività commerciali in un paese, che potrebbero negativamente influenzare un investimento iniziale, il valore dei beni, i flussi finanziari o i profitti. Lo studio analizza le relazioni teoriche tra il rischio paese e la contendibilità del paese stesso. Basato su un approccio olistico, su un modello a equazioni strutturali e su analisi dei dati multivariati, in questo studio viene descritta sinteticamente la struttura del sistema di misurazione del rischio paese di Kanji e Chopra (KCCRMS), nel quale la nozione concettuale del fenomeno del rischio paese è olistica, multidimensionale e multidisciplinare. Inoltre questo lavoro prevede il modo in cui i fattori critici incrementano il rischio in maniera moltiplicativa o come possono interagire, provocando effetti compensatori e di attenuazione reciproci. La struttura del sistema KCCRMS, i suoi effetti e le sue relazioni sono state rigorosamente testate tramite dati derivati da diverse fonti elaborando un’analisi empirica di Marocco, Algeria, Tunisia, Libia e Egitto. È stata costruita una matrice rischio paese per illustrare il rischio sistemico, economico, politico, finanziario e operativo di ogni economia tra quelle selezionate. Sono state realizzate un’analisi del ciclo e della sensitività al fine sia di compiere un’analisi dettagliata dei dati sia di procedere alla loro interpretazione. Questo studio costruisce un indice composito per la classificazione delle economie del Nord Africa in base al rischio paese utilizzando il rating relativo all’investimento. I risultati dell’analisi empirica possono essere impiegati per individuare modalità che consentano di ridurre i vari rischi di investimento in questi paesi.

The paper investigates the dependences between levels of severity of road traffic accidents, accounting at the same time for spatial and temporal correlations. The study analyses road traffic accidents data at ward level in England over the period 2005–2013. We include in our model multivariate spatially structured and unstructured effects to capture the dependences between severities, within a Bayesian hierarchical formulation. We also include a temporal component to capture the time effects and we carry out an extensive model comparison. The results show important associations in both spatially structured and unstructured effects between severities, and a downward temporal trend is observed for low and high levels of severity. Maps of posterior accident rates indicate elevated risk within big cities for accidents of low severity and in suburban areas in the north and on the southern coast of England for accidents of high severity. The posterior probability of extreme rates is used to suggest the presence of hot spots in a public health perspective. Areti Boulieri acknowledges support from the National Institute for Health Research and the Medical Research Council Doctoral Training Partnership. Marta Blangiardo acknowledges support from the National Institute for Health Research and the Medical Research Council–Public Health England Centre for Environment and Health. Silvia Liverani acknowledges support from the Leverhulme Trust (grant ECF-2011-576).

The aim of this study was to assess the nutritional quality of the food supply in Croatian boarding schools and to provide suggestions aimed at its improvement. The work is based on a nutritional survey and nutrition optimization. The survey assessed the food supply in female, male and co-educational boarding schools in Zagreb, Croatia. Particularly, the diets of students aged 15– 19 years were investigated and the relationship between students’ anthropometric measurements and the supply of energy, protein, fat and carbohydrates was analysed. Based on the survey results, nutrition optimization was applied to determine diets meeting the recommended dietary allowances (RDAs) of selected nutrients at least cost. The survey showed that the diets provided in Croatian boarding schools are generally characterized by an oversupply of energy and fat to female pupils and an undersupply of many micro-nutrients to pupils of both genders. This seems to promote the development of obesity in female students. Furthermore, it could be shown by means of nutrition optimization that the nutritional situation in the boarding schools could easily be improved by a reasonable selection and combination of dishes that would also lead to a reduction of food costs. Menu planning by means of nutrition optimization could help to improve the nutritional quality of the food supply in Croatian boarding schools and simultaneously decrease the corresponding food costs.

The autonomic nervous system (ANS) acts modulating the cardiac and respiratory systems by means of the sympathetic and parasympathetic branches. In this work, we propose to employ Transfer Entropy (TE) with the aim of disambiguating the contributions of the two branches over cardiorespiratory regulation in newborns during sleep. Specifically, we computed TE on the original time series representative of the two subsystems, namely Heart Rate Variability (HRV) and Respiration (RESP). Furthermore, we employed a lagged version of the two original signals to derive a TE estimation capable of providing and insight on the short-term memory between the two systems. Results show the information transfer quantified by TERESP→RR decaying rapidly as the shift between the two time series increases. On the other hand, TERR→RESP exhibits a slower but prolonged interaction, which lasts over numerous lags. The novel approach presented in this work affords the potential to assess infants’ ANS development in terms of the quantification of cardiorespiratory control functioning.