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The production of mixed municipal waste changes due to the increase of separation rate, urbanization and other factors. The future changes in the legislation and technology development influences the way the waste is being treated. Thus the method, location and capacity of processing sites are unknown. The realization of future projects can be supported by the developing of transportation infrastructure. Such a feature may be represented by a robust transfer station grid, which can be designed to handle all possible future realizations and technological solutions (establishment of waste treatment facilities). The paper presents an approach utilising a mathematical model for the design of transfer stations. It is formulated as a multi-objective two-stage mixed-integer stochastic programming problem, where the trade-off between the environmental aspect and the economic viability is considered. The model is tested through a case study for the Czech Republic, where the waste treatment of over 6,000 municipalities is analysed. The solutions for different preferences are assessed throughout the principle called out-of-sample stability with 10,000 scenarios. The optimal decision consists of the robust transfer station grid with selected locations and their respective capacity. The particular solution with respect to the potential trade-off suggests to save 1.148 mil of travelled kilometres with only 0.77 mil EUR. The output in the form of decision support can serve possible stakeholders from the field of waste management to plan more sustainable projects. • A transfer station grid designed to handle future realizations and developments. • The efficiency of waste transport was analysed for more than 6000 municipalities. • A trade-off between environmental aspects and the economic viability was considered. • A solution suggests to save travelled 1.148 mil km with only extra 0.77 mil EUR. • Introduction. [ABSTRACT FROM AUTHOR]

This paper investigates a novel type of driver routing and scheduling problem motivated by a practical application in long-distance bus networks. A key difference from other crew scheduling problems is that drivers can be exchanged between buses at arbitrary intermediate stops en route such that our problem requires additional synchronization constraints. We present a mathematical model for this problem that leverages a time-expanded multi-digraph and derive bounds for the total number of required drivers. Moreover, we develop a destructive-bound-enhanced matheuristic that converges to provably optimal solutions and apply it to a real-world case study for Flixbus, one of Europe's leading coach companies. We demonstrate that our matheuristic outperforms a standalone MIP implementation in terms of solution quality and computational time and reduces the number of required drivers by up to 56% compared to approaches currently used in practice. Our solution approach provides feasible solutions for all instances within seconds and solves instances with up to 390 locations and 70 requests optimally with an average computational time under 210 sec. We further study the impact of driver exchanges on the total driver count and show that allowing for such exchanges leads to average savings of 42.69%. • We introduce a novel driver routing and scheduling problem with driver exchanges. • We formulate a MILP based on a time-expanded directed multi-graph. • We propose a matheuristic enriched by a destructive bound improvement procedure. • We demonstrate the performance of our algorithm in a real-world case study. • We provide managerial insights on the impact of driver swaps at intermediate stops. [ABSTRACT FROM AUTHOR]

Previous investigations have revealed the unsafety of the current calculation methods in Eurocode 4 for evaluating the fire resistance of concrete-filled steel tubular (CFST) columns, which has given place to a movement in Europe for correcting the existing methods and developing new design rules. In order to support the development of new guidance, further experimental research is needed, especially concerning slender columns and large eccentricities. In this paper, the results of a series of fire tests on slender CFST columns of different section shape (circular and square) subjected to large eccentricities are presented. The influence of the cross-section shape, load eccentricity and percentage of reinforcement on the response of these columns at elevated temperatures is studied in this paper, focusing on the effect of large eccentricities combined with high slenderness. On the basis of the experimental results, the current design rules in Eurocode 4 are assessed, and a previous calculation method developed by the authors is also evaluated. [ABSTRACT FROM AUTHOR]

Mobile-Based Assessment (MBA) is an alternative or complementary to paper- or computer-based assessment delivery mode. Its successful implementation depends on users' acceptance. However, no study exists exploring the factors that influence students' acceptance of mobile-based assessment. Furthermore, research that combines acceptance with motivational factors is limited. The current study builds on the theoretical framework of the Self-Determination Theory (SDT) of Motivation and the Technology Acceptance Model (TAM) and proposes the Mobile Based Assessment - Motivational and Acceptance Model (MBA-MAM), a combined model that explains and predicts Behavioral Intention to Use Mobile-based Assessment. One-hundred and forty students (N = 140) from a European senior-level secondary school participated in mobile-assisted assessment activities and self-reported their perceptions about ΜΒΑ afterwards. Structured equation modeling used to analyze quantitative survey data. The study confirmed the proposed model, explaining and predicting students’ intention to use MBA in terms of both acceptance and motivational (autonomy, competence and relatedness) factors. The study provides a better understanding towards the development of mobile-based assessments by relating acceptance and motivational factors into an integrated model. Implications are discussed within the wider context of mobile learning acceptance research. [ABSTRACT FROM AUTHOR]

Studying and understanding human brain is one of the main challenges of 21st century scientists. The Human Brain Project was conceived for addressing this challenge in an innovative way, enabling collaborations between 112 partners spread in 24 European countries. The project is funded by the European Commission and will last until 2023. This paper describes the ongoing activity at one of the Italian units focused on innovative brain simulation through high performance computing technologies. Simulations concern realistic models of neurons belonging to the cerebellar cortex. Due to the level of biological realism, the computational complexity of this model is high, requiring suitable technologies. In this work, simulations have been conducted on high-end Graphical Processing Units (GPUs) and Field Programmable Gate Arrays (FPGAs). The first technology is used during model tuning and validation phases, while the latter allows to achieve real time elaboration, aiming at a possible development of embedded implantable systems. Simulations performance evaluations are discussed in the result section. [ABSTRACT FROM AUTHOR]

Abstract: Sizing of stand-alone photovoltaic systems (SAPVS) requires knowledge of their reliability. Because of primary influence of the solar irradiance and meteorological conditions, simulations are the best way to compute an accurate reliability for a given location and fixed sizing parameters. These studies have been developed for more than two decades, but have had a narrow geographical applicability. In this paper, we perform a complete (in time and space) simulation of a standard SAPVS in Europe using 23year radiation data corresponding to almost 2300 geographical points. At each point, the tilt angle that maximizes the energy reaching the PV array in December is estimated and the relation among sizing parameters and reliability is computed for wide ranges of values. Finally, multilayer perceptrons are trained for both computations, allowing (after their training) simple and fast estimations of the sizing parameters of this type of plants for any location in Europe. The procedure presented in this paper, although focused particularly in Europe, can be easily extended to almost any other region in the world. [Copyright &y& Elsevier]

Abstract: Electricity systems models are software tools used to manage electricity demand and the electricity systems, to trade electricity and for generation expansion planning purposes. Various portfolios and scenarios are modelled in order to compare the effects of decision making in policy and on business development plans in electricity systems so as to best advise governments and industry on the least cost economic and environmental approach to electricity supply, while maintaining a secure supply of sufficient quality electricity. The modelling techniques developed to study vertically integrated state monopolies are now applied in liberalised markets where the issues and constraints are more complex. This paper reviews the changing role of electricity systems modelling in a strategic manner, focussing on the modelling response to key developments, the move away from monopoly towards liberalised market regimes and the increasing complexity brought about by policy targets for renewable energy and emissions. The paper provides an overview of electricity systems modelling techniques, discusses a number of key proprietary electricity systems models used in the USA and Europe and provides an information resource to the electricity analyst not currently readily available in the literature on the choice of model to investigate different aspects of the electricity system. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes a 44-year (from 1958 to 2001) wave hindcast conducted for the North Atlantic, using a fine grid in the North East Atlantic coastal areas of Europe. The wind fields were obtained by a local area model that was applied in the areas adjacent to the European coasts, which was forced by the results of the NCEP reanalysis. While the NCEP results have a spatial distribution of 2° and a time step of 6 h the wind fields produced by the local area model have a spatial resolution of 0.5° and a time step of 1 h, which is important for accurate descriptions of the conditions in coastal areas and in rapidly changing storms. A version of the WAM model that allowed two-way nesting was adopted and calculations were made with nested grids allowing a fine resolution in the coastal areas of Europe. This paper includes the description of the set-up of the wave model and the validation performed vs. in-situ measurements so as to allow assessments of the quality of the data produced in this study. [Copyright &y& Elsevier]

[Display omitted] The most common treatment for obstructive coronary artery disease (CAD) is the implantation of a permanent drug-eluting stent (DES). Not only has this permanency been associated with delayed healing of the artery, but it also poses challenges when treating subsequent re-narrowing due to in-stent restenosis (ISR). Drug-coated balloons (DCBs) provide a potential solution to each of these issues. While their use has been primarily limited to treating ISR, in recent years, DCBs have emerged as an attractive potential alternative to DESs for the treatment of certain de novo lesions. However, there remain a number of concerns related to the safety and efficacy of these devices. Firstly, unlike DESs, DCBs necessitate a very short drug delivery window, favouring a higher drug loading. Secondly, while the majority of coronary DCBs in Europe are coated with paclitaxel, the potential mortality signal raised with paclitaxel DCBs in peripheral interventions has shifted efforts towards the development of limus-eluting balloons. The purpose of this paper is to provide a computational model that allows drug delivery from DCBs and DESs to be investigated and compared. We present a comprehensive computational framework that employs a 2D-axisymmetric geometry, incorporates two nonlinear phases of drug binding (specific and non-specific) and includes the influence of diffusion and advection, within a multilayer arterial wall. We utilise this framework to (i) simulate drug delivery from different types of balloon platform; (ii) explore the influence of DCB application time; (iii) elucidate the importance on release kinetics of elevated pressure during DCB application; (iv) compare DCB delivery of two different drugs (sirolimus and paclitaxel) and; (v) compare simulations of DESs versus DCBs. Key measures of comparison are related to safety (drug content in tissue, DC) and efficacy (specific binding site saturation, % SBSS) markers. Our results highlight the pros and cons of each device in terms of DC and % SBSS levels achieved and, moreover, indicate the potential for designing a DCB that gives rise to sufficiently similar safety and efficacy indicators as current commercial DESs. [ABSTRACT FROM AUTHOR]

Abstract: Energy efficiency in buildings is essential for economic, social, and environmental reasons. Under current European legislation, buildings have to be certified with an energy efficiency index. To provide a fair comparison of the energy performance in buildings we need a global and unified representation. In this paper we propose the Energy Efficiency Ontology (EEOnt) to provide a foundation upon which this requirement can be built. EEOnt extends the applicability of other ontological models of buildings incorporating energy efficiency data and knowledge that can be calculated with high spatial and temporal resolution in what we call an Energy Efficiency Landscape (EELB). These EELB''s provide significant information which allows a detailed diagnosis of the energy efficiency within the building. Consequently, EEOnt is capable of representing buildings and energy efficiency in a unified way. Furthermore, it supplies a tool for managing the energy efficiency in buildings and constructing national inventories. These two features link the global and particular needs of governments and users, thus becoming key to both improve the energy efficiency in buildings and to implement viable certification schemes. [Copyright &y& Elsevier]

Abstract: This paper applies a life cycle methodology to estimate activity-related contributions of transport modes to GHG emissions. The methodology uses national input–output tables, environmental accounts, household budget data and nutritional data to derive food-sector GHG coefficients of consumption for ten European countries. The food energy requirements for each mode of transport are estimated taking account of the modal activity level and energy requirements. Typical national food energy-related emissions for walking, cycling, and driving ranged from 25.6 to 77.3 gCO2-eq/pass.km, 10.4–31.4gCO2-eq/pass.km and 1.7–5.2gCO2-eq/pass.km; passenger transport was found to result in no food-related emissions above those for a resting individual. Emissions vary between countries depending on the emissions intensities of their energy sectors as well as food prices and average body weights. A life cycle assessment of modal emissions in the UK is undertaken using the food-energy emissions intensities estimated and car travel was found to have the highest emissions intensity, followed by bus, cycling and walking. [Copyright &y& Elsevier]

Abstract: Hourly and daily solar radiation data are crucial for the design of energy systems based on the solar source. Global irradiance, measured on the horizontal plane, is, generally, available from weather station databases. The direct and diffuse fractions are measured rarely and should be analytically calculated for many geographical locations. Aim of this paper is to present a multi-location model to estimate the expected profiles of the horizontal daily diffuse component of solar radiation. It focuses on the European (EU) geographical area joining data from 44 weather stations located in 11 countries. Data are collected by the World Radiation Data Centre (WRDC) between 2004 and 2007. Different analytic functions, correlating the daily diffuse fraction of solar radiation to the clearness index, are calculated and compared to outline the analytic expressions of the best fitting curves. The effect of seasonality on solar irradiance is considered developing summer and winter scenarios together with annual models. Similarities among the trends for the 4years are, further, discussed. The most adopted statistical indices are used as key performance factors. Finally, data from three locations not included in the dataset considered for model development allow to test the proposed approach against an independent dataset. Obtained results show the effectiveness of adopting a multi-location approach to estimate solar radiation components on the horizontal surface instead of developing several single location models. This is due to the increase of the geographical range of applicability without a significant decrease of the accuracy. The percentage gap between single and multi-location model performances is lower than 20% for the most of the statistical indices adopted for both the model development and ex-post validation through the three independent datasets. [Copyright &y& Elsevier]

Abstract: The optimal combination of yield and quality of hemp fibres from field grown crops is around flowering. Therefore prediction of flowering time would support in planning production and optimization of the cultivar choice for different agro-ecological zones. In the current paper the validation of a recently published model () is carried out for four varieties across a wide range of sites and thus of air temperature–photoperiod combinations. The model was evaluated by comparing its output to field observations of the duration between emergence and 50% flowering. The model output and observed times from emergence to 50% of flowering generally corresponded well, but some discrepancies were apparent. The biggest discrepancies between estimates and actual data were observed at extreme latitudes. The level of accuracy of the model predictions is satisfactory for strategic decision regarding sowing and harvesting time and cultivar choice, but tactical decisions (e.g. time of harvest based on flowering time) cannot be accurately supported. [Copyright &y& Elsevier]

Abstract: In this paper, we study the problem of continuous time option pricing with transaction costs by using the homogeneous subdiffusive fractional Brownian motion (HFBM) , , here , as a model of asset prices, which captures the subdiffusive characteristic of financial markets. We find the corresponding subdiffusive Black–Scholes equation and the Black–Scholes formula for the fair prices of European option, the turnover and transaction costs of replicating strategies. We also give the total transaction costs. [Copyright &y& Elsevier]

Abstract: In Europe, the preferential tax treatment of company cars implies that many employees receive a company car as part of their compensation package. In this paper, we consider a model in which wages and the decision whether or not to provide a company car are the result of direct negotiation between employer and employee. Using this framework, we theoretically and numerically study first- and second-best optimal tax policies on labour and transport markets, focusing on the role of the tax treatment of company cars. We obtain the following results. First, higher labour taxes and a more favourable tax treatment of company cars raise the fraction employees that receives a company car; congestion and congestion tolls reduce it. Second, in countries that provide large implicit subsidies to company cars, eliminating the preferential tax treatment of company cars may be an imperfect but quite effective substitute for currently unavailable congestion tolls. The numerical illustration, calibrated using Belgian data, suggests that it yields about half the welfare gain attainable through optimal congestion taxes. Third, the favourable tax treatment of company cars justifies large public transport subsidies; the numerical results are consistent with zero public transport fares. Finally, we find that earlier models that ignored the preferential tax treatment of company cars may have substantially underestimated optimal congestion tolls in Europe. The numerical illustration suggests that about one third of the optimal congestion toll we obtain can be attributed to the current tax treatment of company cars. [Copyright &y& Elsevier]

Abstract: In this paper, we develop a model which makes it possible to quantify the effects of using fishing periods in a fishery where environmental and fleet productivity uncertainty exist. The model is applied to the European sardine fishery in which, furthermore, the countries implied introduce different management measures in their fishery jurisdiction. The results show that setting fishing periods in order to reach the proposed TAC reduces the risk of over-exploitation of the resource. Also, the global profits are reduced but the cost of reducing the risk of overexploitation is not spread out equally among the countries which participate in the fishery. Portugal incurs the costs of introducing limits on the number of fishing days and Spain obtains the profits obtained from the maintenance of greater stock levels. [Copyright &y& Elsevier]

Abstract: The factors giving impulse to changing major accident prevention legislation within Europe, the so-called Seveso Directive, have not been thoroughly studied and molded into an understandable model thus far. For example the exact relationship between major industrial accidents and an ever changing legislation is still unexplored. This paper thoroughly investigates the parameters having influenced the change of the 1996 Seveso II Directive into the 2003 Seveso Directive Amendment 2003/105/EC and develops the accompanying legislation change process. The official major accident reports of Baia Mare, Enschede and Toulouse are studied in-depth, as well as many other official EU documents. Furthermore, experts from academia, government and industry who witnessed and/or participated into the legislation change process were interviewed in-depth. More profound insights into the societal debate following a major accident may help private companies to adapt their safety management system and their prevention policies, and may aid the legislator to develop more efficient and effective regulations. This way, the societal demand to change legislation in an ad hoc manner may be unpressurized. [Copyright &y& Elsevier]

Abstract: Power grids are prone to failure. Time series of reliability measures such as total power loss or energy not supplied can give significant account of the underlying dynamical behavior of these systems, specially when the resulting probability distributions present remarkable features such as an algebraic tail, usually considered the footprint of self-organization and the existence of critical points. In this paper, 7years (from 2002 to 2008) of Europe’s transport of electricity network failure events have been analyzed and the best fit for this empirical data probability distribution is presented. With the actual span of available data and although there exists a moderate support for the power-law model, the relatively small amount of events contained in the function’s tail suggests that causal factors other than self-organization or a critical state might be significantly ruling these systems’ dynamics. [Copyright &y& Elsevier]

Abstract: This paper presents a universal model of luminous efficacy for direct solar radiation on a horizontal surface. The model is applicable to all sky conditions and is based on data obtained from satellites and available via web servers. Solar radiation data from 10 locations in Europe and North Africa has been used to obtain four functions for luminous efficacy (K) against the sole independent variable solar altitude (α). Additionally cloud amount (C) was been used to obtain four other functions. All were used to accurately estimate illuminance for the 10 originating locations; for four locations based on satellite data; and for a further four based on measured data. A statistical assessment showed that three models performed best, namely, K against 1/α, K against sin α, and K against C/α. Comparison between results from the proposed models, and those produced using three previously published models, indicate that the former produce more accurate estimates of luminous efficacy. The satellite based approach makes daylight data available in locations remote from current measurement sites. [ABSTRACT FROM AUTHOR]

Abstract: The European water framework directive aims to protect the environmental quality of water and encourage its efficient use. EU member states are required to implement efficient water management systems and appropriate water-pricing methods. This paper examines the economic effects that may arise given the introduction of two different methods for pricing irrigation in the Mediterranean area. The considered pricing methods charge farmers for the costs incurred by water user associations (WUAs) in managing water distribution networks. The first method, based on the metered use of water by farms, is known as the volumetric pricing method. The second is an area-based pricing method, whereby fees are charged per hectare according to the estimated average water use for each crop. The economic effects and the impacts on the water usage of these two schemes are analyzed using a mathematical model that represents the farm sector in a Mediterranean area that relies on a dam for irrigation. The possible effects are analyzed under two scenarios: first, the methods are applied to the observed water-pricing conditions, second, an additional charge is introduced to recover unaccounted costs of the water supply system (e.g., long-term costs related to infrastructure, and the operational and maintenance costs of dams) in line with the water framework directive principle of cost recovery. The results show that the introduction of an additional charge via the volumetric pricing method could stimulate the substitution of water provided via collective networks with groundwater. This could adversely affect the financial situation of the WUA and have negative environmental consequences. This negative outcome does not arise in the case that an additional charge is applied via the area-based pricing method. [ABSTRACT FROM AUTHOR]

The objective of this paper is to analyze the role of technology learning in European wind power generation in the presence of public R&D. A Cobb–Douglas cost function is employed to derive a learning curve model for wind power, thus illustrating how the investment costs for this technology are influenced by global learning-by-doing, scale effects, and a European R&D-based knowledge stock. We assume that public R&D expenses targeting wind power add to the above stock, and these R&D outlays are in turn hypothesized to be influenced by technology cost levels, the opportunity cost of public R&D as well as by government budget constraints. We estimate the learning and the R&D model, respectively, using a panel data set covering five European countries over the time period 1986–2002. The empirical results confirm the importance of both learning-by-doing and public R&D support in the cost reduction process, and governments' R&D expenses have declined in response to lowered investment costs. This is efficient in the sense that public funds are best targeted at technologies which are far from being commercial. The results also illustrate that governments in Europe have been sensitive to the opportunity cost of public R&D in the energy R&D budget process. [Copyright &y& Elsevier]

Abstract: Knowledge of temperature at drillable depth is a prerequisite in site selection for geothermal exploration and development of enhanced geothermal systems (EGS). Equally important, the thermo-mechanical signature of the lithosphere and crust provides critical constraints for the crustal stress field and basement temperatures where borehole observations are rare. The stress and temperature field in Europe is subject to strong spatial variations often linked to polyphase extensional and compressional reactivation of the lithosphere, in different modes of deformation. The development of innovative combinations of numerical and analogue modelling techniques is key to thoroughly understand the spatial and temporal variations in crustal stress and temperature. In this paper we present an overview of advances in developing and applying analogue and numerical thermo-mechanical models to quantitatively assess the interplay of lithosphere dynamics and basin (de)formation. Field studies of kinematic indicators and numerical modelling of present-day and paleo-stress fields in selected areas yield new constraints on the causes and the expression of intraplate stress fields in the lithosphere, driving basin (de)formation. The actual basin response to intraplate stress is strongly affected by the rheological structure of the underlying lithosphere, the basin geometry, fault dynamics and interplay with surface processes. Integrated basin studies show that the rheological structure of the lithosphere plays an important role in the spatial and temporal distribution of stress-induced vertical motions, varying from subtle faulting to basin reactivation and large wavelength patterns of lithospheric folding. These findings demonstrate that sedimentary basins are sensitive recorders of the intraplate stress field. The long lasting memory of the lithosphere, in terms of lithospheric scale weak zones, plays a far more important role in basin formation and reactivation than hitherto assumed. A better understanding of the 3-D linkage between basin formation and basin reactivation is, therefore, an essential step in connecting lithospheric forcing and upper mantle dynamics to crustal vertical motions and stress, and their effect on sedimentary systems and heat flow. Vertical motions in basins can become strongly enhanced, through coupled processes of surface erosion/sedimentation and lower crustal flow. Furthermore, patterns of active thermal attenuation by mantle plumes can cause a significant spatial and modal redistribution of intraplate deformation and stress, as a result of changing patterns in lithospheric strength and rheological layering. The models provide useful constraints for geothermal exploration and production, including understanding and predicting crustal stress and basin and basement heat flow. [Copyright &y& Elsevier]

Abstract: A review by Hollander et al. (in preparation), discusses the relative potentials, advantages and shortcomings of spatial and non spatial models of chemical fate, highlighting that spatially explicit models may be needed for specific purposes. The present paper reviews the state of the art in spatially explicit chemical fate and transport modeling in Europe. We summarize the three main approaches currently adopted in spatially explicit modeling, namely (1) multiple box models, (2) numerical solutions of simultaneous advection–dispersion equations (ADE) in air, soil and water, and (3) the development of meta-models. As all three approaches experience limitations, we describe in further detail geographic information system (GIS)-based modeling as an alternative approach allowing a simple, yet spatially explicit description of chemical fate. We review the input data needed, and the options available for their retrieval at the European scale. We also discuss the importance of, and limitations in model evaluation. We observe that the high uncertainty in chemical emissions and physico-chemical behavior in the environment make realistic simulations difficult to obtain. Therefore we envisage a shift in model use from process simulation to hypothesis testing, in which explaining the discrepancies between observed and computed chemical concentrations in the environment takes importance over prediction per se. This shift may take advantage of using simple models in GIS with residual uses of complex models for detailed studies. It also calls for tighter joint interpretation of models and spatially distributed monitoring datasets, and more refined spatial representation of environmental drivers such as landscape and climate variables, and better emission estimates. In summary, we conclude that the problem is not “how to compute” (i.e. emphasis on numerical methods, spatial/temporal discretization, quantitative uncertainty and sensitivity analysis…) but “what to compute” (i.e. emphasis on spatial distribution of emissions, and the depiction of appropriate spatial patterns of environmental drivers). [Copyright &y& Elsevier]

Abstract: In many European countries, municipalities offer their inhabitants a wide variety of social services. In this paper we will focus on efficiently scheduling home care, transportation of the elderly, and home meal delivery. These so-called municipal or communal routing problems can be modeled as different variants of the vehicle routing problem, a well-known optimization problem from the literature. We present a focused literature review and report on case studies using Finnish data. The computational results show that there is a significant potential for cost savings for all applications considered. [Copyright &y& Elsevier]

Abstract: As a fuzzy counterpart of Brownian motion, Liu process has attracted more and more attention in the recent literature. In this paper, the concept of fractional Liu process is proposed as an extension of Liu process. Furthermore, we obtain the expressions of the membership functions, expected values and variances of arithmetic and geometric fractional Liu processes for each fixed time. As an application, geometric fractional Liu process is assumed to characterize the stock price, which formulates a new fuzzy stock model. Based on this proposed model, European option pricing formulas are gained and two numerical examples are given with different parameters. [Copyright &y& Elsevier]

Abstract: The sediment transport processes in the south-western Baltic Sea are predicted by means of a numerical model in the project DYNAS. There are two sediment parameters that influence the results of modelling remarkably: critical shear stress velocity and bottom roughness. This paper presents the way how to parameterise these factors and extrapolate them into the investigation area. The critical shear stress velocity is parameterised basing on grain size data, combining approximations after Hjulström [Hjulström, F., 1935: Studies in the morphological activity of rivers as illustrated by the river Fyris. Geological Institution of University of Uppsala: Bulletin (25): 221–528.], Shields [Shields, A., 1936: Anwendung der Ähnlichkeits-Mechanik und der Turbulenzforschung auf die Geschiebebewegung. Mitteilungen der Preussischen Versuchsanstalt für Wasserbau und Schiffahrt (26): 26 pp.] and Bohling [Bohling, B., 2003: Untersuchungen zur Mobilität natürlicher und anthropogener Sedimente in der Mecklenburger Bucht. unpublished doctoral thesis, Mathematisch-Naturwissenschaftliche Fakultät, Ernst-Moritz-Arndt-Universität Greifswald/Germany, 156 pp.]. The roughness length, in the case of absence of macro zoo-benthos and their structures, is parameterised basing on grain size too employing Soulsby [Soulsby, R.L., 1997: Dynamics of Marine Sands: a Manual for Practical Applications. London, Thomas Telford Publications. 249 pp.], Nielsen [Nielsen, P., 1983: Analytical determination of nearshore wave height variation due to refraction shoaling and friction. Coastal Engineering 7, 233–251.] and Yalin [Yalin, M.S., 1977: Mechanics of Sediment Transport. Pergamon Press, New York. 298 pp.]. No equivalent simple parameterisations for biologically caused bed roughness exist. Here, findings of Friedrichs [Friedrichs, M., 2004: Flow-induced effects of macro zoo-benthic structures on the near-bed sediment transport. Dissertation, Universität Rostock, 80 S.] and estimations by the DYNAS biologists group were combined in order to derive roughness lengths from abundance measurements of four previously selected key species which represent the originators of the dominating benthic structures at the sea floor in the south-western Baltic Sea. Critical shear stress velocity and bed roughness are known at few sample sites only. They were extrapolated into the larger investigation area using a proxy-target concept. The mean near bottom milieu (bathymetry, median grain size, salinity, oxygen) which was derived using results from numerical modelling serves as the proxy. Since the milieu parameters are measured at the sampling sites for which the target parameters have been determined, a combined hierarchical and supervised classification was employed to transfer the local knowledge into the unknown investigation area. [Copyright &y& Elsevier]

Abstract: The Bulgarian Emergency Response System (BERS) is being developed in the Bulgarian National Institute of Meteorology and Hydrology since 1994. BERS is based on numerical weather forecast meteorological information and a numerical long-range dispersion model accounting for the transport, dispersion, chemical and radioactive transformations of pollutants. In the present paper, the further development of this system for a mixture of radioactive gaseous and aerosol pollutants is described. The basic module for the BERS, the numerical dispersion model EMAP, is upgraded with a “dose calculation block”. Two scenarios for hypothetical accidental atmospheric releases from two NPPs, one in Western, and the other in Eastern Europe, are numerically simulated. The effective doses from external irradiation, from air submersion and ground shinning, effective dose from inhalation and absorbed dose by thyroid gland formed by 37 different radionuclides, significant for the early stage of a nuclear accident, are calculated as dose fields for both case studies and discussed. [Copyright &y& Elsevier]