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Abstract

Groundwater study through the operation of geoelectric, considered one of the best known way in the field. Consideration and accuracy in accurate extraction of water and using the proper equipment and interpret detailed data can reveal high potential of these methods in the best way for underground exploration. This study was conducted to investigate the separation of fresh and saline water, using the analysis and interpretation of geoelectric data collected by the array Schlumberger. Because human needs for fresh water for drinking water, agriculture, animal husbandry and industry, and difficulties in the initial identification layer of saline water in these important activities, find a way to solve these problem is very important. The purpose of case study conducted in southwestern of plains Eshtehard is recognition of border of saltwater and freshwater for wells to provide water for the construction of water wells to water supply for greenhouses exist in the region. In this study, by obtaining data geoelectric and their interpretation, was observed that by increasing the amount of EC (electrical conductivity) due to presence of the solute salts in certain depth of groundwater, sudden drop in specific resistivity be seen in specific range of Probing taken, and according to studies carried out in different regions of the world, these sudden change is known as the boundary separating fresh and saline water, that study and comparison of geophysical data with log obtained from drilled wells in these area, also is a confirmation of these fact.

Abstract

The urgency of the study is conditioned by the necessity of perfection of the methods of electro-aerosol disinfection and disinsection of the air and the surfaces of premises, medical and preventive treatment of animals, and plant protection. The objective of the paper is aimed at revealing the regularities of electro-physical processes when charging an aerosol in electro-aerosol generators, improvement of the methods of electro-aerosol generation. The leading approach to the research of this problem is mathematical modelling of electrotechnical, dynamic and kinetic processes in electro-aerosol generators, allowing revealing the basic regularities of electro-aerosol generation. Experimental studies are aimed at assessment of the main characteristic of the electro-aerosol generator – convection current. As a result of the studies, a mathematical model of electro-aerosol generation with the mechanical method of atomization was obtained. The regularities of charging a fluid thread, arising at the edge of the generator, when applying electric field. The configuration of the electric field of cylindrical electrodes, taking into account the influence of the bulk charge of the electro-aerosol cloud, was considered. Electrostatic pressure of the electric field of the generator on fluid streams was taken into consideration. An equation for determining the average radius of drops of the electro-aerosol during mechanical atomization by the perforated cage was obtained. The mathematical model of electro-aerosol generation is obtained in the form of the equation of convection current, being one of the basic characteristics of the process of electro-aerosol generation, allowing defining the efficiency of electrization of aerosol particles and the degree of their fragmentation. Theoretical calculations are verified experimentally. Materials of the paper can be useful for the researchers, post-graduate students, engineers, engaged in designing, manufacturing and exploiting electro-aerosol equipment.

Abstract

The relevancy of the study is due to low efficiency of using solar and geothermal energy in the existing process schemes. In this regard, this article is aimed at revealing the possibilities of using solar and geothermal energy for the integrated energy supply of separate facilities from renewable energy sources. The mathematical simulation method based on the theory of graphs of energy system operation, which makes it possible to analyze the efficiency of the integrated use of solar and geothermal energies for the heat-cold supply of separate facilities, is the main approach to studying this problem. Energy consumption throughout the year and the emergency energy source capacity in “peak” modes were determined based on the developed mathematical model of managing the system of integrated power supply of separate facilities from renewable energy sources plotted with the use of the theory of graphs. The article materials are of practical value for the designers of the systems of integrated heat-cold supply of separate facilities.

Abstract

Surface roughness has an important role in retarding the runoff velocity. The increase in paving blocks usage, particularly in urban areas, can change the surface roughness of the land. This study investigated the effects of four types of concrete block pavements (CBPs) in retarding the surface runoff velocity. Three design parameters based on CBP properties that considerably influenced the flow retardation were promoted. They were opening ratio (Or), void ratio (Vr) and straight channel ratio (Sr). A tilted plot equipped with a rainfall simulator was used to investigate the influence of surface slope and rainfall intensity to the flow on various CBPs. A modified dye tracing method in view was performed to monitor the surface flow velocity under various rainfall intensities. Flow retardation coefficient (Frd) were calculated based on velocity data on smooth pavement and on CBPs layer measured under the same slope and rainfall intensity. The results showed that flow retardation coefficient increased with an increase in openings ratio, rainfall intensity and surface slope. The relationship between flow retardation coefficient and all design parameters was expressed by a linear regression function. A further study is required to increase the accuracy of the model by modifying the regression function and increasing the variation of design parameters.

Abstract

In the context of the Algerian energy policy, and through the review of the Algiers’ residential building stock, this paper explores the correlation between the energy consumption of gas and electricity with urban density. Based on a holistic approach of the 57 Algiers’ municipalities, the analysis is organized in two ways. Firstly, the spatial approach is conducted within a GIS implementation, carried out based on the 2013 aggregated annual energy consumption data. The cross analysis of Electricity and Gas consumption and density of population within a GIS spatial distribution approach shows effectively a strong correlation between urban density and energy consumption with a Pearson correlation of −56% and −65% of the Electricity and Gas consumption in the urban municipalities, respectively. Also, the household located in the suburban municipalities consume clearly more energy than the urban centered ones. Based on the electricity and gas consumption, density and carbon footprint we have clustered, within a PCA, the Algiers’ municipalities into three profiles: the “thrifty”, the “intermediate” and the “wasteful” profile.

Abstract

Understanding space-time correlation in equilibrium matrix when force of collision involving earthquake stress strain interaction. The proposed study shows that non-linear dynamics of earthquake behaviour simulated with ant colony optimization in short timescale deformation by analysis of the stiffness matrix and the stress strain interaction process of the rock pattern. An improved ant colony optimization combined with local search is proposed for solving this complex optimization problem of finding trigger zones for earthquake occurrences. The disturbances at trigger basins for any system cause the collapse of a subsystem leading to stress evolution and slip due to strain nucleation. The stress strain network based on redistribution of stress accumulation are discretized into four states of low stress and strain and a finite element model is established to identify vertices for the stress-strain component and edges for global coupling effects have been constructed for dynamic monitoring of stress and strain behaviour at triggering zones. In this paper, an efficient algorithm is developed for the formation of null basis of triangular and rectangular plate bending finite element models, corresponding to highly sparse flexibility matrices. Triggering basins serve as harbingers of large earthquake where stress-strain interactions have been analyzed by the quasi-static mechanics of seismic precursory stress-strain propagation in the crustal lithosphere. The simulation framework shows that with time, spatial triggering points as stress varies from one point to another to identify the external influences for the body forces and the surface forces for geodynamic frameworks.

Abstract

Objective of the present study is to define the dynamic mechanical response of multi-story structures acted upon by wind. Structural response is associated to the dynamically applied wind and is approached by considering its three components: static, kinematic and energy states. Proposed objective is achieved by structural dynamic analyses performed on multi-story steel structures in elastic domain. The dynamic model is the multi-degree of freedom system associated to lateral story level displacements. Dynamic forces are computed from recorded velocities of wind through a simple velocity – pressure – force transform. The matriceal differential equation of wind induced vibratory state is dealt with by both, direct integration and modal decomposition. The three components of the mechanical state are expressed via base shear force – the static state, lateral story-level displacements – the kinematic state and wind induced energy – the energy state. Modal decomposition of the dynamic response allows for immediate computation of modal contribution to the total wind response. Computed values of the parameters are numerically and graphically presented and commented. Relevant conclusions are inferred.

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Abstract

This paper outlines for construction specialists the concept of "passive house", presenting the actual status of research and breakthroughs within this field within the country and abroad but also the directives of the European Council and European Parliament regarding this concept. Last, but certainly not least, it showcases some of the flaws of the European Directive regarding passive houses, because it fails to bring forth viable solutions for a number of dire issues.

Abstract

A new methodology based on Principle of Quasi Work is used for calculating the deflections in plates. The basis of this methodology is concept of topologically similar systems. Present method uses a priory known solution for deflection of a simply supported plate for arriving at the deflection of any other topologically similar plate with different loading and boundary conditions. This priory known solution is herein referred to as reference equation. Present methodology is easy as deflections are obtained mostly by elementary mathematics for point loads and for other loads by integration that’s integrant is reference equation multiplied by the equation of load. In the present methodology solution of fourth order partial differential equation in two independent variables as used in lengthy and not so easy conventional method is bypassed.

Abstract

The paper presents aspects regarding the component of the HVAC system and their monitoring system of a school building, which use both energy efficient concepts and renewable energy solutions