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The seismic investigation of buildings is in accordance with two important Romanian Codes, P130/1999 and the seismic design code P100-2013. Criteria for selecting buildings proposed to be seismic investigated/monitored are numerous: seismic zoning of the territory; data on structural system and types of existing structural systems, depending on the material pre and post-1940; the effect of vibration other than from the seismic vibration; location-site; seismic stations and sensors, sensors position/location in a b...

The proper selection of the structural steel grade has to take into account a lot of factors and, for structural steels, a minimum ductility is required so that the material shall have sufficient fracture toughness to avoid brittle fracture of the tension elements at the lowest service temperature. In this paper we present the methodology for selecting the toughness of structural steel with respect to EN 1993-1-10: 2003 and SR EN 1993-1-10: 2005. Establishing the steel sub-grade for the steel main girders of a rai...

The two-dimensional profile curves created by Barton are often used in geotechnics for the determination of the rock joint coefficients. These two-dimensional profiles of solid surfaces show self-affine properties, i.e. they are scaled differently in x- and y- directions. Similarly, the three-dimensional reliefs (3D) of solid surfaces are scaled differently in z-direction in comparison to x- or y-directions. Therefore, the vertical sections of surface reliefs (two-dimensional profiles) are self-affine curve (self-...

Currently, the design and development of the user interface is important, but at the same time, an empirical process. Despite the attempts of many authors to give recommendations on the correct design of the interface appearance, there are no recommendations on how to relate the domain and interface, and build the latter without losing the sense of the user's activity. Unlike the existing approaches in this area, the proposed approach to the semantic design takes into account the activity of the user in the domain...

The air traffic in the European Union and operation of individual airports, including service provisions, belong among the most unregulated industries. Free market economies result in keen airport competition, and especially those airports are affected that compete for customers of the same catchment area. Passengers prioritize airports not only because of the quality of the services offered and provided but passengersпїЅ priorities also reflect presentation strategies of airports, as well as their communication a...

Usually the frost heave of soils causes damages to low-rise buildings, road paving, and pipelines. However, a few years ago unusual deformations of a building supported by 18 meter piles were found. It was a cooling house designed for fish storage at the temperature of -22пїЅ-24пїЅ?. The building was 8,4m high; its plan dimensions were 24?42m. To protect the ground against the frost penetration a 0,9 m layer of light gravel under the concrete floor was filled and an electrical heating system under it was set up. T...

There is an increased concern about the constantly mounting amounts of sewage sludge due to different factors, in particular population growth and urbanization. Therefore, besides common sewage sludge disposal, innovative solutions are required, such as by energy recovery. The present research aimed at evaluation of the energy potential of sewage sludge from a Romanian municipal wastewater treatment plant. A viable and sustainable solution for the removal of sludge is the "transfer" of this so-called waste, in pel...

The exploration of shale oil is still the actual problem in the Western Siberia. The Upper Jurassic Bazhenov bituminous strata are widespread here. The Bazhenov strata is perspective shale formation because it has the high quantity of organic carbon and considerable thickness. This region is the most interesting for exploration of shale oil. The object of research are located within the Koltogor-Urengoy paleorift and its fraiming structure. The reconstruction of the tectonic and thermal history of Bazhenov formati...

Today, we have to follow the principle of sustainable development in relation to the surrounding environment. Bearing in mind the mandatory requirements for energy efficient buildings, special attention should be paid to the strategy of conduct. In this respect, the key factor is the ability to visualize not only the building but also individual elements, including: cross-sections of walls, ceilings, roofs, presentation of potential materials before the necessary work is carried out. Such a state project is possib...

The paper explores the possibilities of defining geometry and its behaviors with using ESO digital tools in an integrated structural and architectural design. It is an response to the current needs geared towards sustainability, combining ecological and economic efficiency. The first part of the paper defines the Evolutionary Structural Optimization tools, which were developed specifically for engineering purposes using finite element analysis as a framework. The development of ESO has led to several variations wh...

Authors examined particularities in shelf oil and gas production. Social-economic aspects have been revealed of consequences during underwater production and pipeline transportation of hydrocarbon crude. Volumes of losses from emergencies at pipelines and platforms were analyzed with differentiation of principal world shelf oil and gas production regions. Loss volumes were estimated for the North-Eastern European region with reference to components of hydrocarbon production and transportation systems. Methodical a...

In paper the most important input variable revolutions (rpm) of drilling tool is analyzed by utilization of Shewhart control chart. The revolutions of drilling tools have a double meaning, in term of the performance and economics. Two measured variable namely pressure force F (N) and speed of rock drilling v (mm.s-1) closely related with revolutions. In general, control charts are used as a proven means to improve the qualitative parameters of production and in the prevention of errors, discrepancies in production...

In Poland, beavers have colonised all types of valley landscapes пїЅ from late glacial coastal lowlands and lake districts in the north of the country to upland and mountainous ones in the south. Studies of geomorphological effects of their presence in valleys of small rivers in the Oder and Vistula River basins have confirmed the results of earlier observations conducted in forest zones of North America and Europe. In Polish territory, effects of the changes related to the beaversпїЅ activities have been studied ...

In this study, the geomechanical properties of the heterogeneous limestone rocks in ??rnak coal mine roof cemented at cracks and the effect of the qualities of cementing paste fill on strengthening by the different silica fume paste were investigated. For this purpose, uniaxial compressive strength, point load strength, impact resistance, friction with Abrasion Loss, Impact Abrasion Loss (Los Angeles Assay) tests were managed following the cemented 50x50x50mm blocks. Even the physical properties; density, water ab...

Maozhou watershed is a highly urbanized watersheds in southern China that is a typical watershed in ChinaпїЅs rapid urbanization. Changed land use/cover(LUC) within the watershed changed the flood response, that requires the model parameter updating with the LUC changes induced by urbanization to have an accurate flood forecasting. Flooding in Maozhou watershed is serious, which was aggravated by increased urban land area within the watershed. Accurately forecasting the flood of Maozhou watershed is imperative, bu...

This paper is focused on the simulation using Matlab/Simulink software? of the Photovoltaic (PV) cell/module/array for a better understanding of the power generated under different atmospheric conditions (irradiance and temperature). One diode model and double diode model of a PV cell are also shown in this paper. The simulations could be performed considering both models, but here only the PV caracteristics for one diode model will be shown. The resulting model uses a friendly interface considering the Function B...

A starting point for roadheader robotisation (understood as a fully autonomous machine) is to automate the cutting process, which is the basic working process carried out by such machines. In case of boomпїЅtype roadheaders, it consists in automatic control of the movement of cutting heads to ensure that the face surface can be worked with optimum process parameters. This will guarantee high drilling efficiency (drilling advancement) and lower energy consumption, reduced dynamic loads and elimination of overloads....

In a large competitive environment in which today foundry exist are more important is production of castings with high quality and high economic efficiency. Therefore, the use of 3D software and simulation programs is necessary in the pre-production stages. In them it is possible to design, construct and simulate filling and solidification of castings in the foundry mould, design ingate system and feeder system. A properly designed and calculated ingate and feeder system is the first prerequisite for producing of ...

The ground serves as an ideal heat source for monovalent ground-coupled heat pump (GCHP) systems. This paper presents a working methodology and develops an analytical model for evaluation of the ground thermal conductivity and the borehole thermal resistance using a thermal response test (TRT). Additionally, this paper uses the Earth Energy Designer (EED) simulation program developed on the basis of the line-source model to calculate the fluid temperature for a case study of the ground heat exchanger according to ...

This article examines formation and simulation of interferences in new licensed frequency within communication in NGA 4G LTE networks, which are source of disturbing of radio and television broadcasting. This also use for increase of awareness about interference problematics in access network. This article is dealing with sources of interference within licensed zones, its creation and also provides theoretical and applied possibilities of its technical solution between licensed zones. Article provides experimental...

Many oil and gas low permeable reservoirs have been stimulated to enhance productivity. Acid fracturing is one of the commonly used well stimulation treatment in carbonate formations, such as limestone, dolomite, and chalk. Carbonate reservoirs are good candidates for acid fracturing since strong acids such as hydrochloric acid react easily with carbonate. The acid reacts within the fracture to create a differentially etched surface that will maintain a conductive pathway. Habitually, a pad fluid is injected ahead...

The aim of this study was to develop a rapid and relatively simple protocol for the simultaneous quantitative determination of the main volatile compounds acetoin and diacetyl found in yogurt. Both these substances are the common flavor components in cultured dairy products. Acetoin/diacetyl determination is important because its concentrations represent criteria for the quality appreciation of the lactic starter cultures. This proposed method employs the reactions of acetoin and diacetyl with 1-naphthol and creat...

Sulphate precipitation from mine water as ettringite, Ca6Al2(SO4)3(OH)12пїЅ26H2O, is generally indicated to be implemented as a second treatment step, following the heavy metal precipitation or as a third step, after gypsum seeded crystallization. The whole process may be seen as complicated by the operators, which always prefer simpler flow sheets, with fewer steps and with lower investment cost, but this treatment process sequence is justified by sludge management depending on type and by the economic reasons re...

The aim of the article is to evaluate the Six Sigma method as a tool changing the way energy industry has been managed. It has been based on facts, data and results of statistical analysis. The methodпїЅs task is streamline and continuous development of new, increasingly sophisticated solutions of all processes in a company, particularly concerning the protection of the environment. The philosophy was found to act by a clear identification of a value for a customer as part of a long-term strategy regarding variabi...

The presented paper deals with the design and examination of steel towers of electrical transmission lines with circular or polygonal cross section. Structures of this kind are a safe and reliable option when selecting the appropriate structural solution, but nevertheless often remain omitted due to difficulties with design methodology. The cross sections of conical towers are in majority of cases categorized as class 4 sections. Being classified as such, they are in certain loading situations considered as shell ...

The combination of wood-PVC was used for the first time at an outdoor fire test on a reduced scale. From a scientific point of view, there is a strong the need to repeat similar fire test with a combination of materials that occur in the interior of buildings. It opens the opportunity to confront theory with the results of similar tests carried out. The combination of traditional and modern materials in interiors of buildings occur very often. Both wooden and or wood-plastic composite materials are mainly used to ...

The article discusses the need to introduce energy management of municipally-owned buildings provided by the concept of Smart Cities. Cities use many buildings. These buildings also have a different nature of use, such as offices, schools, social care homes, etc. All these buildings consume energy that needs to be monitored and regulated. Energy management needs a large amount of relevant data on these buildings together in one comprehensive system. When planning building revitalization, it is necessary to have su...

In this work are highlighted a few basic features of the smart clothes. This concept is extremely useful, it represents the future and this time, technology will be used to monitor out body to not only make life easier for us. The smart clothes purpose is that to monitor the human body behavior throughout the day without discomforting the persons somehow. In case if it detects an abnormal reading of the data received from various sensors, using the fuzzy logic the system will issue a warning on a certain level dep...

The analysis of naturally fractured reservoirs is very comprehensive because of their structure, which includes the matrix of high porosity and low permeability as well as fractures of low porosity and high permeability. The situation is more complex in gas-condensate reservoirs in which the condensate accumulates in the fractures, what prevents them to maintain their base role as the most permeable conduit for the hydrocarbon flow. One of the most successful process to enhance recovery from dual porosity reservoi...

An accurate simulation of snowmelt infiltration rates for an area of Bucegi Mountains, during spring thaw, has been made using the snow routine of HYDRUS- 1D. The model is based on coupled flow and heat transport in the vadose zone. The snowmelt routine is based on degree day concept. As boundary conditions are used, surface water and heat fluxes can be calculated from the energy balance equation. The variables of the surface energy balance equation and melt rates can be calculated using meteorological data: air t...

Every infrastructure development project encroaches upon habitable space and the natural environment. Local communitiesпїЅ doubts concerning construction projects cannot be effectively dispersed without public debate and the dissemination of reliable information. This is a very important consideration because infrastructure development is a public service, and construction takes place on land that constitutes private property at the planning stage. Public opposition can halt construction, and developers who disreg...

The goal of this article is answering the question about what role can be played - as well as what role is actually being played - by thermal waste processing plants in Poland. The beginning of the XXI century is a time of new pro-environmental ideas. This is associated with an increase in the awareness of societies regarding the necessity of protecting the planet that we live on, as well as with the depletion of the natural resources that are at our disposal. In the face of such intense environmental changes, it ...

This paper reviews the main transborder issues on the territory of Commonwealth of Independent States (former USSR) of principally associated with natural and human induced hazards involving waste contamination from extractive industries. The Soviet Union included 15 states that had unified political and economic system. In 1991, after the collapse of the USSR, on the territory of the previously united country, were formed 15 independent states, respectively new boundaries were shaped, and existing environmental p...

Free geodetic networks are networks of points which absolute coordinates are not known, but only their relative position in relation to each other. This network is invariant to translation and rotation, and possibly a change in the scale. Degrees of freedom of this type of network cause singularity of the normal equations coefficient matrix N, therefore the use of general inverse is required, and the most commonly used is Moore-Penrose inverse or pseudoinverse. This paper presents available commercial software whi...

The work is devoted to the development of a domestic catalyst of ethylene acetoxylation for the synthesis of vinyl acetate is relevant. Non-stationary process of vinyl acetate synthesis from ethylene, oxygen and acetic acid is being implemented in a tubular reactor by passing the gas mixture of the initial reagents through the catalyst bed. It has been established that using hydrothermal treatment of silica gel in an autoclave at varying temperature and processing time it is possible to obtain the samples with dif...

The Lojane arsenic-antimony deposit with its former mine facilities, for a longer period, represents source of contamination with heavy and toxic metals into the air, water and soil. Remains of mine waste in Suvi Potok near the Vakcince village, open waste and concentrate storage pond from the Lojane Mine and storage of reagents and toxins near the Tabanovce village represent source of pollution with As, Sb, Hg, Tl, Pb, Mo, Mn etc., which directly threaten surface and ground water in the vicinity of Vaksince, Loja...

Along the whole history, the human civilizations were depended mainly on the soil fertility and further on the ecosystem well function and its appropriate characteristics. These functions (as natural processes occurring in ecosystems) depend on its structure (on biotic and abiotic constituents respectively) and provide ecosystem services. The paper emphasized the way that one of the ecosystem services, essential to our health and well being, as the пїЅregulation of the nutrients and their uptake? arises from the i...

The paper describes and analysis loess substrate collapsing under embankment as a result of flooding. The threat of huge settlements is wide spread on large loess deposits areas especially in south part of Asia. The popular in Russian Federation and common used method developed by authors is the compaction of substrate by soil columns. It is used in a variant covered with geosynthetic as barrier and reinforcement under an embankment. Authors present results of numerical calculations in direct numerical determinist...

The paper presents the physical and mechanical behaviour of an expansive clay, coming from a site in Cluj-Napoca, Romania enhanced by a polyethylene waste material. Given the current research directions of international projects, this paper fits the less studied theme of the usage of recyclable materials for soil stabilization. According to recent studies, in EU just 40% of waste materials are recycled and this low percentage opens a wide perspective for the re-usage of these materials as fillers in stabilized soi...

In the context of climate and land use changes, the dynamics of soil carbon content became an interesting topic taking into account the role of soil organic matter for both plant growth and soil quality. Various analytical methods are accessible to find out the organic carbon concentration in soil with distinctive accuracy, each of them having own constraints and gains. The aim of the present study was to compare the experimental results obtained for soil organic carbon through several methods (wet dichromate oxid...

The coal-fired power stations are particularly complex polluting agents, furnishing simultaneously, high and low environmental pollution sources, through the chimneys for burning gases evacuation and the ash dumps, respectively. The Deva-Mintia coal-fired power stations has an installed power of 1260 MW, six power units of 210 MW each group having two steam boilers of 330t/h, the energy being produced by the coal extracted from Jiu Valley mining area. Coal-fired power station Mintia is located in South East Transy...

Biochar is a porous, carbon-rich material produced by heating of organic matter to temperatures between 300 пїЅC and 1000 пїЅC in an environment with limited or no oxygen. During the past decade, numerous articles focusing on the use of biochar have been published, but have shown inconsistent results. Reactions in the soil after the addition of biochar depend on the characteristics of biochar, soil, climate and soil-inhabiting organisms. However, due to high variability in the quality of biochar, its effects on so...

The article deals with numerical analysis of vertical normal contact stress in subsoil of foundation slab of 16-storey monolithic reinforced concrete frame building situated in Kiev, Ukraine. The foundation gap is located 11.65 m below the level of surrounding terrain. Numerical calculations are verified with real measured values of contact stress (published in Lazebnik, 1998) in four different cross sections of foundation slab. The problem is solved as spatial (3D) with complex interaction of пїЅupper structure п...

In this paper, the authors discussed one of the Hume-Rothery conditions for occurring substitutional solid solutions in the context of binary relations. The analyzed condition says that substitutional solid solutions may form if the ionic radius of the solute and solvent ions differ by no more than 15%. Because the problem concerns a mathematical connection between two objects, the authors suggested describing this problem using the set-theoretic notion of binary relation. In this context, the possibility of formi...

A method of solving the selection problems with fuzzy parameters by means of a special algebraic structure is proposed. To construct such an algebraic structure, we propose a special transformation of existing fuzzy numbers to the simpler form (L or R number) while keeping the most of the initial expert information. This structure avoids deficiencies limiting applicability of the other known structures, such as unjustified extension of the uncertainty, violation of certain natural relations, openness of the carrie...

The article is devoted to solving the problems of the receving indicators of agricultural land, which is characterized not only by fertility, but other indicators, defining the status of agricultural land. Such indicators are indicators of the federal monitoring of lands that allow timely identification and application of methods of land management changes in economic activity, which enables you to optimize land use and sustainability of agricultural land. It is shown that one of the basic problems of land monitor...

The temperature of some surface and ground waters in Romania was measured during the 2015-2017 time interval at high temporal resolution in order to identify the main thermal properties and their oscillation. The water monitoring in B?ile Felix area was undertaken at Fp3 water well and Ochiul Mare Lake. The measuring sites in Geoagiu-B?i area are represented by water pumped from F3 water well and a thermal spring in Cibului Gorge. The outflowing groundwater from 2 water wells was measured in HпїЅr?ova area. In ord...

This paper presents a possible alternative solution to cold a retail center located in Brasov, Romaine. Absorption machines using thermal energy are excellent alternatives to mechanical refrigeration.The proposed solution uses a single stage absorption systems working with LiBr-water. This solution uses the water as a refrigerant which has a null direct impact on the environment (ODP=0 and GWP=1).The proposed scheme is the result of experimental research conducted by a team from the Thermodynamics, Heat Transfer a...

The present paper represents a first for Romania as it aims to empirically analyze the 26 collision cases between military aircrafts and birds registered during 1967 пїЅ 1991. The paper is based solely on the observations made in the above-mentioned period by the Chief of the Meteorological Division within the Romanian Air Force Headquarters between 1990 and 1993 (PhD meteorological engineer and retired commander). This article completes various scientific and statistical studies in the field, which were missing i...

The article observes the results of numerical simulation of the interaction of socketed shafts with rocks under the action of horizontal loads. The study revealed the following features of deformation and failure of the system "shaftпїЅ rock mass". Analysis of the obtained results confirmed the conclusion previously made by other researchers that the curve of deformation of the socketed shaft may be approximated by bi-linear dependence, in which the inflection point corresponds to the end of the linear section of ...