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Development of numerical methods allows on much more better examination of changes in foundation-soil interaction. However, there are still some areas which require more analysis and discussion, because results of simulations on are often divergent to the field tests. One of these problems is numerical modeling of displacement pile installation and proper consideration of its influence on surrounding soil. Application a simple FEM model can be not sufficient, by its limited application in changes of soil considera...

Most of researchers explain that shallow tunnels suffer higher damage compared to deep structures. Many numerical analyses were carried out in order to verify and compare the stresses, forces and bending moments acting on tunnel lining according with the seismic design. After tunnel modelling in MIDAS GTS NX to investigate the tunnel simulation in order to highlight the effect of static and dynamic load on the behaviour of tunnel lining for different cases and calculated the value of each mesh node based on 3D fin...

The paper presents numerical modelling results for ventilating a blind excavation, if there is a leakage into a failure zone. The leakage value of air seeping through the failure zone (binomial law of resistance) was estimated by a formula describing in-situ tests results at the Kola Peninsula mines. The blind excavation ventilation process was simulated based on a previously developed two-stage methodical approach: 1st stage пїЅ calculation of aerodynamics with applying a standard ?k ?? ? -turbulence model; 2nd s...

This study deal with numerical investigation of river sea interaction. River mouth modelling is one of the most complex problem in coastal engineering because of meteorological and oceanographic uncertainties. Although river-sea interaction has been complex problem, these areas have significant importance for human life such as dense population near this places, environmental importance, transportation etc. During the riverпїЅsea interaction numerical modelling just one defined or steady condition modelling is nev...

Linear programming problems are optimization problems where the objective function and constraints are all linear. Mathematica has a collection of algorithms for solving linear optimization problems with real variables, accessed via LinearProgramming, FindMinimum, FindMaximum, NMinimize, NMaximize, Minimize, and Maximize. LinearProgramming gives direct access to linear program- ming algorithms, provides the most flexibility for specifying the methods used, and is the most efficient for large-scale problems. FindMi...

Fruit juices are consumed worldwide, not only for their flavour, taste, and freshness, but also due to their beneficial health effects when are consumed regularly. Being relevant sources of vitamins, minerals and polyphenolic compounds many people are becoming aware of the importance of consuming them in their daily diet. The citrus juices, lemon, lime and grapefruit juice is the most appreciated and used because of its flavour and high content of vitamin C. The purpose of this study was to analyze and compare som...

Frequent alternations of high and low temperatures and of rainy and dry weather, which were increasingly felt in recent decades have reduced harvests. Thus, the identification of varieties with genetic characteristics that provide a better adaptability presents a particular importance. Although a cultivar is known as the most important technological link in terms of production stability, the quantity and quality are influenced by the climatic conditions. Observations were conducted in the experimental fields of th...

In post-mining areas appearance of uncontrolled mining gas exhalations can be observed. Methane migrating through the strata, together with soil air may create explosive mixtures. Occurrences of mining gases are caused due to discontinuation of water pumping process in abandoned mines and fast rising and restoration of water table. However, itпїЅs not obvious, that all hydrocarbons in soil pores come from abandoned hard coal mines. Often in soil pores mixtures of microbial and thermogenic gases are observed. For i...

The goal of this article is to present the problem of sustainable, self-sufficient and off-the-grid buildings in cold climates. Living off-the-grid is a part of the drive for sustainable living, in accordance with the principles of sustainable development. Buildings that are self-sufficient and which are not a part of the traditional power generation infrastructure have, on average, a much smaller environmental footprint and produce much less carbon dioxide, relying on renewable energy sources and environmentally ...

The dynamic development of material and chemical engineering as well as physical analytical methods allows the use of new materials for the production of drilling muds. This is especially important because drilling works are conducted in increasingly difficult geological and technological conditions. The present analyses concentrate on the development and elaboration of recipes of drilling fluids with organophilic nanomaterials. One of the most frequently applied nanomaterials referred to in patents registered by ...

Today, as a result of the depletion of low- and medium-density oil deposits, the world faces the problem of increasing oil production by involving non-traditional, alternative sources of hydrocarbon raw materials, which include fuel shale. In the area of the Volga-Ural oil and gas province, tight shale hydrocarbons reserves are located in domanic sediments. Quantity and spatial distribution of organic matter of domanic species remains underinvestigated. Assessment of oil potential, generation of mobile hydrocarbon...

The subject of the study is architectural and space-planning structure of the buildings and residential complexes, methods for their adaptation perspective to the post-Olympic period. Sustainable and effective development requires taking into account the possible future use and the economic principles, methods and means of architectural formation for the buildings in residential part of the international sport activities centers. Formation principles of architecture, green design, accessible and energy saving plan...

The problem of a vortex pair motion under a free surface is considered. It is known (Barker S.J. & Crow S.?., 1977) that the vortices fly apart with respect to each other in the horizontal direction. The domain of computation will be on the half-plane with the symmetry condition on one of the vertical boundaries. Previously was received (Gushchin V.A. & Konshin V.N, 1992), that for the correct mathematical modeling of an unsteady thick layer of homogeneous incompressible liquid flow through an obstacle, it is nece...

Eco-grammar systems represent grammar systems which were motivated by the behaviour of ecosystems. They were introduced in 1994 in order to describe evolving environment and community of agents together with the interplay among them. Positioned eco-grammar systems (PEG systems, for short) were introduced in our previous paper as a variant of the eco-grammar systems. Motivation for introducing the PEG systems and its main difference from the original eco-grammar systems is that we focus on the embodiment of the age...

Design of a structure together with monitoring the structural response to dynamic loads (seismic and hydrodynamic), fatigue aging, the possibility of successive degradation, resilience respective vulnerability are strongly influenced by the chosen calculus model, and a laborious probabilistic calculation. For particular case of offshore structures this implies the connection between the actions of the environment: wave histograms, wind action, foundation collapse, structure, technological activities and so on. Als...

The article presents the materials of long-term research conducted from 2004, in the mouth area of the Northern Dvina River. The program of researches included determination of concentrations of mercury in the water, covering about 150 km of the river length. We also analyzed such parameters of water as pH, Eh, oxygen content, salinity. A long observation period allowed us to trace the peculiarities of the changes of mercury content in water, which was the aim of the present work. Previously the authors determined...

The Danube Delta dynamics formation and expansion represent the motivation of the study included in this paper. The results of soil studies made possible to develop the Danube Delta genesis maps [7]. That informationпїЅs are the input data and the validation data for the numerical flow studies of the Danube River. The study of the formation of new territories has been developed by the Computational Fluid Dynamics (C.F.D.) method. There were modelled in three dimensions the maps for Danube River Basin flowing into ...

Simulation modeling methods allow researchers to create models of complex systems. And it still remains a scientific field. Our purpose is to implement simulation models in training, but as a destination also to business пїЅ to actually use autonomous applications as support systems decision-making in the tourism industry. This paper considers some opportunities of the system for simulation modelling GPSS World Personal Version for creation and applying simulation models in the training managers in the hotel busin...

This paper reviews a developed technology of mining steeply dipping mineral occurrences by steeply inclined sublayers, taking into account spatial position of sublayers relative to ore shoot. Parameters of phase and steeply inclined sublayers, till reaching final open pit depth, have been justified during studies. An order of steeply inclined layers formation on frontal open pit edges is determined depending on location of mineral resources on footwall and hanging wall. A new method of reactivation of a non-operat...

The study focuses on saving energy in the process of drinking water distribution in the rural area. The hydraulic model of the water distribution network that supplies Dulcesti village, Constanta County, Romania, developed in EPANET is the basis to performing a thorough analyse of the hydraulic systemпїЅs operation. The standard hourly water demand is taken into account. The network is a branched one, widen on a large area so that the ratio is about 10m of pipe per inhabitant. The difference in junction elevation ...

The purpose of this article is describing a project of underground facility at the Technical University of KoпїЅice. The idea of schoolпїЅs mine established by the Technical University of KoпїЅice started a few years ago as a result of needs to improve learning process in study programs related mining, tunneling and geotechnologies and improvement of practical education. We take as example mines or other underground facilities that are used in the learning process at our partner Universities in the Czech Republic ...

One of the most popular systems of simulation - GPSS World provides users (1) software tools to interact with the system in the process of simulation research and (2) software tools, realizing immediately the implementation of the model (including: syntax analyzer interpreter model, clock modeling, management of the list of events and more.). Until a few years ago the programs in the first group only automated a part of research itself, namely the creation of a text model and conduct experiments with it. In the ab...

Developing lipid products with colloidal structurally and functionally modified properties, others than the starting base, playing a structural role in the integrated product and the role of mycelia carriers to ensure a health status is relatively recent and it is the result of accepting the idea that foods play a determining role in the prophylactics and therapy of certain conditions. The paper approaches two main aspects: 1 пїЅ methods of modifying lipids (simple stir, hydrogenation, interesterification, fractio...

The energy sector is an essential component in any nationпїЅs economy and well-being. The security and safety of any energy grid system is nowadays a strongpoint in mid and long term strategies when it comes to national development. Safety and security of energy supply is a multicomponent factor that includes: power generation systems, power transport and distribution systems and consumer management. The power generation units in Romania are very complex and they include different sources like coal, gas, nuclear, ...

Reliability of a concrete pipe culvert was tested under rail and embankment loads. In the finite element model soil-structure interaction and nonlinear behavior of the materials were taken into account. After a preliminary study three influential variables as random were selected for presented approach to probabilistic model, i.e. concrete strength, soil density and its modulus of elasticity. Because various concrete parameters can be easily derived from the compressive strength only this parameter was selected fo...

Fodder yeasts are widely used in animal feeding as a source of protein with high amount of B vitamins. While plant protein is very poor in such amino acids like lysine, methionine, tryptophan, single cell protein contents all complex of essential amino acids. Studies have shown advantages and possibilities of using single cell protein in complex with plant base for animal feeding. Sunflower is being one of the most cultivated agriculture in Russian Federation. Deproteinized sunflower meal is a secondary product of...

The emergence and development of the internal combustion engine began in the 18-th century in England. But the first patent for a piston engine with compression ignition was achieved by Rudolf Diesel in year 1892 [1]. The engine use coal powder as fuel. The most used vegetable oil as a fuel and peanut oil. In the year 1859 in Pennsylvania was first released at the amount of crude oil that has been refined for kerosene and gasoline. Because a large quantity of by-products remained unused, Rudolf Diesel using a frac...

Countries that largely base their production of electricity and thermal on coal, are exposed to a significant burden of the environment, mainly through the emission of harmful substances into the environment, including the production of large quantities of solid waste: including fly ashes, slags, ash, slag mixes etc. However, the waste generated in combustion processes does not have to be a burden to the environment. Due to the changes in legal regulations they may become a by-product (i.e. Coal Combustion Product...

In this paper is developed a model for the wastewater treatment plant (WWTP) in Arad, Romania and are presents the results of the steady-state simulation. The model of the plant was based on the stateпїЅof-the-art Activated Sludge Model No.1 (ASM1). In this paper are describes all the steps required to model a waste water treatment plant. In addition, discuss the major challenges encountered in creating a model. It includes typical model simulations for assessment analysis facility. Modeling of wastewater treatmen...

Costs in mining and extractive enterprises is a critical factor for competitiveness. The reason is enormously expensive equipment and technology associated with this type of business. It is therefore necessary to identify the so-called critical cost type, not only in enterprise but also in the entire industry of the country. Slovak Republic, calculated on an area, belong to one of the world's mining superpowers and take leading positions in mining of selected types of raw materials [6]. Mineral resources are the b...

Lots of modern heat supply systems were designed and constructed many years ago, but used today with low efficiency. The task of optimization of heat supply systems to increase the efficiency of such systems is related with high capital expenses of such process, but also with high mutual integration of heat supply systems with other infrastructure objects. In this regard the heat supply organizations are faced with a task of optimization of the efficiency indicators of functioning heat supply systems with minimal ...

In this article questions of increase in effectiveness of the equipotential method (its adaptation) for a research and monitoring of karst processes are considered. Authors carried out the analysis of the principles of creation of systems of monitoring on the basis of the equipotential method. Mathematical justification of formation of compensation signals for sensitization of the applied equipotential method is given in work. Algorithms of the regression analysis for increase in reaction of system of monitoring t...

The article deals with optimizing CFD model of the gravitational heat pipe to the creation of substitute materials and the optimization of its properties, depending on the actually measured results of the experimental device. Gravitational heat pipe operates on the principle of phase change working fluid (heat transfer fluid). The very principle of heat transfer is based on the theory of evaporation and condensation of the working fluid (heat transfer fluid). Heat pipes are classified according to the method of op...

Renewable energy is playing an important role in the development of any modern country. Numerous renewable energy sources are now harvested on a large scale with the main purpose to reduce the greenhouse gas emissions and diminish the use of fossil fuels. European Union member states agreed to achieve important quotas of renewable energy in their consumption until 2020 in energy and in transportation. Romania has the legislation aligned with the EU directives, therefore the government has issued specific legislati...

The scientific paper deals with the multi-criterion optimization of the teeth that are used on the buckets of bucket wheel excavators. From past theory and practice, it is known that geometry of the tooth greatly influences the cutting parameters and the endurance and the strength of the tooth itself. The dependencies between the cutting forces, the penetrating forces, the specific energy on the rake angle and the relation between this last one and the robustness of the tooth are somewhat contradictory, so in the ...

The aim of the article was to present the possibilities of logistic solutions of management system of mixed waste and segregated waste that can be one coherent system or two parallel systems. The authors of the article attempted to optimize the transport of various waste fractions from their origins and collection to recycling and storage sites. The assumptions and limitations of adopted systems as well as conclusions are presented. Sustainable waste management should follow the hierarchy: waste prevention, reuse ...

The paper deals with optimization of point cloud data processing for surface representation of objects with complicated structure. The model object in our research is represented by a coniferous tree with difficult structure obtained by the method of terrestrial laser scanning. Its precise geometric expression and vector representation is essential and it provides the basis to study the impact of natural conditions to the state and development of the coniferous tree using geographical information systems in the fi...

Alkylphenols (APs) are toxic, xenobiotic substances classified as endocrine disruptors, which have a negative effect on the hormonal system of many organisms including humans. APs are among the ubiquitous environmental contaminants and are frequent contaminants in wastewater. Alkylphenols are starting materials for the production of many surfactants and antioxidant stabilizers used in commercial products like detergents, plastics and textiles. They are used in the synthesis of alkylphenol ethoxylates (APEs) and ar...

The present paper uses microsimulation softs to identify the main problems regarding the speed humps location and proposes some improved solutions, with effects on traffic, pollution and safety. This paper also defines the notion of "speed hump", its main advantages, disadvantages and some implementation requests. The most accessible measures to increase road safety, both in economic and design terms, are the traffic calming measures, such as speed humps in different shapes and sizes, low-price solutions with sati...

Terrestrial Laser Scanning (TLS) in LiDAR technology is a commonly used method in obtaining geometric information about objects. Individual scan stations can be combined into one project using the cloud-to-cloud method or based on targets (chessboards or spheres). Target-based registration with spheres is very convenient because in planar view always circle is visible, no matter of the angle of view. On the other hand, it is inconvenient to use the same size of spheres throughout the project. Large spheres are eas...

The aim of this article is to describe the possibility of increasing the service life of the rod eye on a tilting platform that is used to tilt heavy barrels between the two differences in heights in transport lines. This mode of transport was selected for the lack of space in a given area of a production line, which does not allow the implementation of an inclined plane, which would be structurally easier. Rotating those barrels by 90пїЅ that is achieved during this way of transport, is desired for subsequent tec...

Petroleum and petroleum products hydrocarbons are the most toxic environmental contaminants. Modern detailed analysis of crude oil is needed for assessment, trasological and forensic investigations. Method of gas chromatography with mass spectrometry (GC/MS) is one of the most effective method for the component composition determination in complex mixtures. This paper describes an express developed methodology for determination of fractional and component composition of crude oil and its derivative products пїЅ di...

Cereals and by-products of its processing are known to be applied for lactic acid bacteria fermentation. Wheat grains containing starch, protein and a lot of growth factors seem to be the rich nutrient media for some types of microbes. On the other hand, the niglible number of lactobacilli can produce amylases and proteinases (for native gluten decomposition), so at least the partial hydrolysis of substances mentioned is needed. The complex processing of wheat flour with amylases and proteases was shown to increas...

The annual extraction of aggregates in the Czech Republic is between 45 - 50 mega tones. [5]. Many studies for better results of quarries are undertaken. In this paper is solved the question of optimizing. It is solved the optimizing of cost on coal quarries also. The situation on stone and coal quarries is different. There are requirements for stone production, but the production of coal is in decrement. Comparison and solving both situations seems to be useful. The relationships between different production proc...

The annual extraction of aggregates in the Czech Republic is between 45 - 50 mega tones. [5]. Many studies for better results of quarries are undertaken. In this paper is solved the question of optimizing. The relationships between different production processes in quarries are very important matter. On the relationships between the manufacturing processes depends the economic effect of operation. The paper presents patterns in the organization of mining, which mutually related. Using computational methods and the...

Limestone deposits are primary raw material for cement manufacturing plants. However, mining engineers and geologists faces challenges in determining an appropriate, accurate and cost effective estimation method. The aim of this research is to evaluate and compare the applicability of two geostatistical methods, Ordinary Kriging (OrK) and Inverse Distance Weighting (IDW), for estimating quality of the Ta Thiet limestone, a lithological structure deposit at Binh Phuoc province (Vietnam). For this purpose, data coll...

In the article are given the results of the study of chemical and organic composition of natural waters (bog, river and underground). The samples were collected on territory of the largest bog system in the world пїЅ The Vasyugan bog at the mouth of the rivers Vasyugan and ParabelпїЅ (Tomsk region). It is shown, that for all types of waters are characteristic of increased concentrations of iron (from 1 to 12.5 mg/l) and organic matters (COD from 4 to 30 mg/l), at the same time contents them are directly proportion...

Organization of the Access database of the Kadiica copper deposit Eastern Macedonia represents the first attempt of this paper authors to synthesize geological exploration data of this ore bearing locality in one professional database available for the wider auditorium. Authors experience in organization of similar databases for other metal deposits such are Bucim, Borov Dol, Zletovo, Sasa etc., gave us an opportunity to construct quality Access database for the Kadiica deposit. This deposit is of porphyry type wi...

Research conducted on sterile dumps resulting from surface mining of lignite, have shown that in the waste dump restoration process, the main issues are raised by the non-uniformity of texture, extreme textures, lack of structure, low content of organic matter, the deficiency in macro (NPK) and micro (Cu, Zn, Fe, Mn) nutrients and low biological activity. Most experiments with fertilizers revealed that the maximum yield was achieved in variants fertilized with high doses of organic fertilizers, in addition with mi...

Coworking (also called as пїЅoffice for hours") is a relatively new tool on Polish real estate lease market. This is a solution primarily for people predominately working at home who want to develop their business. The service consists of providing office space equipped with office furniture with internet access and other facilities. The idea of an office for hours is primarily dedicated for freelancers. That kind of solution gives a number of advantages, nevertheless appearing on real estate lease market in many ...