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The monitoring of quality of the urban air environment takes a big part in reaching good environmental conditions. The model of neural networks for forecasting of distribution of nitrogen dioxide in the surface layer of the air environment is shown in this research. The model is based on meteorological data and the information of sources of emissions of polluting substances. The optimal network configuration was determined on the basis of standard deviation and the quality of education. This is the cascade network...

The aim of the work is to assess consequences of polychaetes Marenzelleria spp. invasion for the Gulf of Finland ecosystem in a future climate. With this objective benthic submodel of the 3-dimentional eco-hydrodynamic Saint-Petersburg Baltic sea Eutrophication Model (SPBEM) was applied. In the model 4 numerical experiments were carried out: 1) 2 control runs excluding the effects of Marenzelleria spp. under two different scenarios of global climate change (based on ECHAM5 model of Max Planck Institute of Meteorol...

The aim of this study is to assess the impact of climate change on the frequency and magnitude of marine hazards (extreme) events. The study was carried out for the Baltic Sea, which is under increasing pressure of maritime activities and becomes more vulnerable to climatic effects due to declining seasonal ice cover. Estimates of extreme events are derived from the current global and regional hydrodynamic climate models that have been used to define the marine boundary conditions, atmospheric and riverine forcing...

In this article the air infiltration through the envelope of a naturally ventilated building, located in Bra?ov (Romania) is studied. The paper presents the study of the factors which influence the air infiltration ? wind effect and stack effect ? and the modeling of air change rate (ACH) inside the building, by Multiple Linear Regression (MLR) modeling. It has been found that ?T can be a good predictor of ACH because of its high physically correlation with this. Another conclusion of the study is that although wi...

Thermal pollution is considered to be one of the physical water pollution types that is caused by dumping of water heated by the units of industrial, thermoelectric and nuclear power stations. This type of pollution is characterised by the increase of water temperature higher than the natural level. At the places where heated water is dumped there are zones with water temperature higher than in the whole reservoir: about + 12° ? in winter and + 30° ? in summer. This fact results into the increased amount of organi...

The study deals with the features of using surfactants during waterflooding of an oilsaturated porous medium in the pore-scale. As an example of the study, we use natural sandstone from Ash'alchinskoye oil-field. For calculations the digital image of this sample is received with high resolution X-ray computer tomography use. The mathematical modeling of multiphase flow in porous medium is made on the base of Lattice Boltzmann equations and Color-field model. Numerical experiments are held for different values of s...

Industrial and social development of mountain regions in the south part of Siberia requires reliable estimation of the river flow. The runoff is mostly formed by rainfalls and melting. Scarce network of hydrometeorological stations and their location in valleys make interpretation of precipitation spreading in high mountains disputable. Therefore, mathematic modeling of runoff volume is of prime importance. Complex approach to mountain small catchments runoff estimation is suggested. River flow modeling is based o...

The purpose of this article is to describe the modern methods of making models of quarry using the latest technologies such as laser scanning, land and air photogrammetry using Unmanned Aerial Vehicles (UAV) and their subsequent use in the planning of technological processes in the quarry. The first part of the article is dedicated to the creation of models with a focus on data collection and processing, compatibility of each format, the very creation of the model as well as the possibility of using the created mo...

The article presents modeling data on taxes and average annual salary in Bulgaria. This information is stored in a created relational database containing twelve tables. Updating the database is done each year, and the respective new records are entered into the indicated tables. The data about the taxes that are included in total expenditure of households by expenditure groups, average annual salary in Bulgaria and average annual salary by regions (North-West, North Central, North-East, South-East, South-West and ...

Aerogels production consists of two main stages: preparation of the gel filled with solvent (alcohols, acetone or hexane) by polymerization or sol-gel process and its supercritical drying. The most energy consuming and complicated from a technical point of view is the drying step [1]. Supercritical drying allows keeping the internal structure by preventing collapse of pores. Supercritical conditions require the use of expensive highpressure apparatus and the process rate is limited by diffusion within the pores of...