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EN
Purpose: Water is vital for the sustenance of every life form. Urbanization, growing population and industrial development has led to exploitation of water resources globally. This study assesses quality of water resources of Mohammedia prefecture. Design/methodology/approach: The water quality analysis was carried out based on physio-chemical and heavy metal concentrations. The physio-chemical analysis comprised of status of concentration, overall quality and water pollution index evaluation. The heavy metal evaluation consisted of Ecological Risk Index, non-carcinogenic risk and carcinogenic risk assessment. Findings: The landfill near Ben Nfifikh River reported insignificant (WPI<1) – low level of pollution (>1≤1.5) for surface and groundwater points. However, the groundwater for Zenata region was found to pose both carcinogenic (CRt > 0.0001, range 0.4-35.31) and non-carcinogenic risks (HQ>1, range 6 -34) of higher degree rendering it unfit for human consumption. Hence, this study concludes that groundwater resources should not as water supply; instead, Oud El Maleh River can serve as surface water source for meeting requirements of Zenata region. Research limitations/implications: The data obtained can be categorized as landfill area near river Nfifikh and landfill area near river El Maleh. Both areas have been investigated for groundwater and surface water quality assessment. Practical implications: This study demonstrates the need to study the characteristics of groundwater (depth, flow rate, water renewal, etc.) before arranging a waste dump. This problem is especially relevant for arid countries, since residents experience a shortage of water, as well as a lack of rainfall provides a weak renewal of groundwater, which can contribute to the accumulation of a higher concentration of carcinogens in groundwater and provide a high risk to public health. If policymakers in arid countries and decision-makers have effective water quality maps, then the country can be more efficiently managed water resources without risking the population. Originality/value: The current study is planned as a multi-stage, each of which is supposed to conduct field studies of groundwater and surface water quality with appropriate parameters, analysis of institutional reports and related scientific studies in order to create an effective water quality map for rational water use.
EN
Purpose: To evaluate the superpave design performance using Epolene (EE-2) as modifier, since SUPERPAVE design is a modified and sophisticated aspect as compared to previous mix design for asphalt mixtures. This is primarily due to the fact that superpave design mix also takes into consideration properties of materials beside asphalt. Design/methodology/approach: This study was conducted using Epolene (EE-2) as modifier in order to evaluate the performance of SUPERPAVE suitability for construction of roads in Alfaraa campus (King Khalid University) Abha, in Asir Province of Saudi Arabia. Glow number test, dynamic modulus test and indirect tensile strength test were conducted to evaluate the performance of EE-2 modifier against the control mixture. Findings: The mixture modified with EE-2 gave better performance in terms of temperature-based performance and resistance to moisture damage. Also, larger values of E*/sinφ were obtained for EE-2 modified mixture at various loading frequencies and temperature in comparison to control mixture. Research limitations/implications: The Epolene modifier successfully enhances and improves the SUPERPAVE mixture performance. Further studies are required to evaluate the performance of EE-2 modifier at much lower temperature ranges. Practical implications: The results of the study allow us to recommend the investigated asphalt mixture for applied for the construction of roads in the Alfaraa (new campus of King Khalid University), Abha, Asir province, Saudi Arabia. Originality/value: A modified asphalt mixture has been proposed that has better performance at higher and lower temperatures. The developed asphalt mixture is more resistant to moisture damage than the compared to control mixture.
EN
Purpose: Experimentally substantiate the possibility of using the developed jet-centrifugal spraying device in plants spraying technologies. Design/methodology/approach: Many years of experience in creating spraying devices for solving practical problems in various industries made it possible to propose a design diagram of a single-phase jet-centrifugal spraying device. The tests were aimed at achieving device characteristics that are acceptable for use in plants spraying technologies such as jet coverage distance, droplet size and droplet deposition area (spray diameter). For this a several tests series with different design parameters was done. Before testing, the tightness of the device body was checked (the holding time under a pressure of 1 MPa is not less than 2 minutes). Findings: Based on the obtained jet coverage distance, droplet size and droplet deposition area, the developed spray device of some modifications can be used in plants spraying technologies. However, it is necessary to determine the quality of the spray device according to the BCPC classification; the device should be tested with some insecticides, fungicides and in plants spraying technologies to develop recommendations for their use. Research limitations/implications: The influence of design features of developed jetcentrifugal spray device on the jet coverage distance, droplet size and droplet deposition area was studied. Practical implications: The results obtained are useful in the field of improving national plants spraying technologies in order to improve the quality of the plant protection agent application and reduce the loss of the drug into the environment. Originality/value: To ensure maximum efficiency the proposed design of the jetcentrifugal spray device can be upgraded directly by the farmer by installing interchangeable nozzles that are attached with a union nut. Replaceable nozzles have different diameters and modifications and can be selected depending on the required jet coverage distance and spraying dispersion according to the current environmental conditions.
EN
Purpose: To develop and implementation in practice an algorithm for smart monitoring of workplace environmental physical factors for occupational health and safety (OSH) management. Design/methodology/approach: A brief conceptual analysis of existing approaches to workplace environmental physical factors monitoring was conducted and reasonably suggest a decision-making algorithm to reduce the negative impact of this factors as an element of the OSH management system. Findings: An algorithm has been developed that provides continual improvement of the OSH management system to improve overall labour productivity and which has 3 key positive features: (1) improved data collection, (2) improved data transfer and (3) operational determination of the working conditions class. Research limitations/implications: The implementation of the proposed algorithm for substantiating managerial decisions to reduce the negative impact of workplace physical factors is shown by the example of four workplace environmental physical factors in the products manufacture from glass. Practical implications: If management decisions on the implementation of protective measures are taken in accordance with the proposed monitoring algorithm, these decisions will be timely and justified. This makes it possible to reduce the time of the dangerous effects of physical factors on the health of workers and reduce the level of these factors to improve working conditions. That is, an algorithm is proposed that provides continuous improvement of the OSH management system to increase overall labour productivity. Originality/value: Current monitoring of workplace environmental physical factors values are carried out in accordance with the justified monitoring intervals for each factor that provides the necessary and sufficient amount of data and eliminates the transfer of useless data.
EN
Purpose: This investigation aims to study the various approaches currently used to reduce the load on computer servers in order to better manage data on hospital wastewater treatment and solid waste generation. Design/methodology/approach: This manuscript investigates the taxonomies of deduplication procedures based on literature and other data sources, thereby presenting its classification and its challenges in detection. Findings: Based on the literature survey of deduplication techniques, the method of deduplication dispensed on cloud gadget devices has been found to be a promising research challenge. The gaps discussed include a reduction in storage space, bandwidth, type of disks used, and expenditure on energy usage and heat emissions when implementing these strategies. The art work on a scalable, robust, green and allocated approach to deduplication for a cloud gadget will remain of interest in destiny. Research limitations/implications: Considerable attention is focused on the deduplication due to efficient, extensive storage system. Practical implications: This research paper will be useful to identify deduplication techniques which are nowadays used in different hospital wastewater data collection systems and put significant proposals for further improvements in deduplication. Originality/value: This manuscript portrays a broader assessment of the available literature for data duplication along with the classification of different methods for the data storage used in the different level of storage of hospital wastewater data collection.
EN
The actual motivation of this paper is to develop a functional link between artificial neural network (ANN) with Legendre polynomials and simulated annealing termed as Legendre simulated annealing neural network (LSANN). To demonstrate the applicability, it is employed to study the nonlinear Lane-Emden singular initial value problem that governs the polytropic and isothermal gas spheres. In LSANN, minimization of error is performed by simulated annealing method while Legendre polynomials are used in hidden layer to control the singularity problem. Many illustrative examples of Lane-Emden type are discussed and results are compared with the formerly used algorithms. As well as with accuracy of results and tranquil implementation it provides the numerical solution over the entire finite domain.
EN
An investigation is performed for an alyzing the effect of entropy generation on the steady, laminar, axisymmetric flow of an incompressible Powell-Eyring fluid. The flow is considered in the presence of vertically applied magnetic field between radially stretching rotating disks. The Energy and concentration equation is taking into account to investigate the heat dissipation, Soret, Dufour and Joule heating effects. To describe the considered flow non-dimensionalized equations, an exact similarity function is used to reduce a set of the partial differential equation into a system of non-linear coupled ordinary differential equation with the associated boundary conditions. Using homotopy analysis method (HAM), an analytic solution for velocity, temperature and concentration profiles are obtained over the entire range of the imperative parameters. The velocity components, concentration and temperature field are used to determine the entropy generation. Plots illustrate important results on the effect of physical flow parameters. Results obtained by means of HAM are then compared with the results obtained by using optimized homotopy analysis method (OHAM). They are in very good agreement.
EN
Time-Frequency (t-f) distributions are frequently employed for analysis of new-born EEG signals because of their non-stationary characteristics. Most of the existing time-frequency distributions fail to concentrate energy for a multicomponent signal having multiple directions of energy distribution in the t-f domain. In order to analyse such signals, we propose an Adaptive Directional Time-Frequency Distribution (ADTFD). The ADTFD outperforms other adaptive kernel and fixed kernel TFDs in terms of its ability to achieve high resolution for EEG seizure signals. It is also shown that the ADTFD can be used to define new time-frequency features that can lead to better classification of EEG signals, e.g. the use of the ADTFD leads to 97.5% total accuracy, which is by 2% more than the results achieved by the other methods.
EN
This investigation analyses a three dimensional flow and mass transfer of a second grade fluid over a porous stretching wall in the presence of suction or injection. The equations governing the flow are attained in terms of partial differential equations. A similarity transformation has been utilized for the transformation of partial differential equations into the ordinary differential equations. The solutions of the nonlinear systems are given by the homotopy analysis method (HAM). A comparative study with the previous results of a viscous fluid has been made. The convergence of the series solution has also been considered explicitly. The influence of admissible parameters on the flows is delineated through graphs and appropriate results are presented. In addition, it is found that instantaneous suction and injection reduce viscous drag on the stretching sheet. It is also shown that suction or injection of a fluid through the surface is an example of mass transfer and it can change the flow field.
EN
In this paper, an extension is introduced into Max-Min Improved Euler methods for solving initial value problems of fuzzy fractional differential equations (FFDEs). Two modified fractional Euler type methods have been proposed and investigated to obtain numerical solutions of linear and nonlinear FFDEs. The proposed algorithms are tested on various illustrative examples. Exact values are also simulated to compare and discuss the closeness and accuracy of approximations so obtained. Comparatively, tables and graphs results reveal the complete reliability, efficiency and accuracy of the proposed methods.
EN
Gabor Wigner Transform (GWT) is a composition of two time-frequency planes (Gabor Transform (GT) and Wigner Distribution (WD)), and hence GWT takes the advantages of both transforms (high resolution of WD and cross-terms free GT). In multi-component signal analysis where GWT fails to extract auto-components, the marriage of signal processing and image processing techniques proved their potential to extract autocomponents. The proposed algorithm maintained the resolution of auto-components. This work also shows that the Fractional Fourier Transform (FRFT) domain is a powerful tool for signal analysis. Performance analysis of modified fractional GWT reveals that it provides a solution of cross-terms of WD and blurring of GT.
12
Content available remote Exact solutions for unsteady incompressible viscous fluid flows
EN
Two-dimensional, unsteady, laminar equations of motions of an incompressible fluid with variable viscosity are considered. The problem investigated is the flow for which the vorticity distribution is proportional to the stream function perturbed by a generalized uniform stream making an angle with the positive x-axis. Employing transformation variables, the goveming Navier-Stocks Equations (NSE) are transformed into steady state equations and then simple ordinary differential equations and a class of exact solutions are obtained. Several graphs of physical interest of streamline are also displayed and discussed.
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