Preferred Language
Articles
/
joe-1478
Dynamic Behavior of Machine Foundations on layered sandy soil under Seismic Loadings
...Show More Authors

In this paper, a dynamic investigation is done for strip, rectangular and square machine foundation at the top surface of two-layer dry sand with various states (i.e., loose on medium sand and dense on medium sand). The dynamic investigation is performed numerically using finite element programming, PLAXIS 3D. The soil is expected as a versatile totally plastic material that complies with the Mohr-Coulomb yield criterion. A harmonic load is applied at the base with an amplitude of 6 kPa at a frequency of (2 and 6) Hz, and seismic is applied with acceleration – time input of earthquake hit Halabjah city north of Iraq. A parametric study is done to evaluate the influence of changing L/B ratio (Length=12,6,3 m and width=3 m), type of sand, and frequency of the machine for soil with two layers (dense and medium sand) and (loose and medium sand). It was noticed that the displacement decreases when the foundation is strip, and has the highest values when the foundation is square. At the same time, the maximum vertical stress of the foundation (L/B = 4 and L/B = 1) appears to be (1262) kPa and (1255) kPa, respectively, due to increasing the foundation mass as a result of increasing its dimensions. Then again, the displacement increases by 20% for vertical displacement when decreasing the relative density. In addition, it has been noticed that there is a decrease in displacement when the frequency value changes from (2 to 6) Hz.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon May 01 2023
Journal Name
Iop Conference Series: Earth And Environmental Science
Screening and optimization of a novel gallic acid and tannase production under semi quantitative and quantitative methods
...Show More Authors
Abstract<p>Tannin acyl hydrolase as the common name of tannase is an inducible extracellular enzyme that causes the hydrolysis of galloyl ester and depside bonds in tannins, yielding gallic acid and glucose. The main objective of this study is to find a novel gallic acid and tannase produced by <italic>Acinetobacter Baumannii</italic>. A number of optimization steps were followed in order to improve the highest production of gallic acid and tannase. In present study, <italic>A. baumannii</italic> were isolated from ICU burn. <italic>A. baumannii</italic> was examined by microscopic examination, morphological and biochemical assay including oxidase and catalase. The </p> ... Show More
View Publication
Scopus (4)
Scopus Crossref
Publication Date
Fri Dec 15 2023
Journal Name
Bionatura Journal. Ibero-american Journal Of Biotechnology And Life Sciences
Efficacy of the entomopathogenic fungus, Metarhizium anisoplae, against Khapra beetle Trogoderma granarium (Coleoptera: Dermestidae) under laboratory conditions
...Show More Authors

Publication Date
Sun Jun 07 2009
Journal Name
Baghdad Science Journal
Compatibility between Pseudomonas fluorescens and Trichoderma harzianum in disease control of Fusarium tomato wilt under greenhouse condition .
...Show More Authors

This study was conducted to evaluate the efficacy of 6 isolates of Pseudomonas fluorescens and Trichoderma harzianum and there combination against Fusarium tomato wilt disease caused by Fusarium oxysporum F.sp. Lycopersisi under green house condition .The isolates of bacteria (B3) and Trichoderma (T1) were found to be highly effective in reducing the disease incidence to 13.3% , 21% respectively , compared to control treatment (40%).Furthermore, disease severity was reduced to 28 and 30% respectively in comparison to control (90%) .Colonization of the roots (cfu /g fresh root weight )by the two isolates whether alon or together was extremely high . The combination treatment had a high ability in reducing disease incidenece and sev

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jun 26 2022
Journal Name
Electrical Engineering
Optimal insulation design of form-wound stator winding with stress grading system under fast rise-time excitation
...Show More Authors

The effective insulation design of the stress grading (SG) system in form-wound stator coils is essential for preventing partial discharges and excessive heat generation under pulse-width modulation excitation. This paper proposes a method to find the optimal insulation design of the SG system aimed at reducing the dielectric and thermal stresses in the machine coil. The non-uniform transmission line model is used to predict the voltage propagation along the overhang, SG, and slot regions considering the variation in the physical properties of the insulation layers. The machine coil parameters for different insulation materials are calculated by using the finite element method. Two optimization algorithms, fmincon and particle swarm optimiz

... Show More
Crossref (1)
Crossref
Publication Date
Mon Mar 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
The dialectical relationship between the organization's growth and its value under the framework of the diversification strategy
...Show More Authors

The research is conducted on target of investigating the role of growth strategy via diversification in value maximization of a firm in terms of controversies literatures had witnessed. Using a descriptive approach for analyzing and verifying the harmony of variables of research and their conceptualized logic , it could be reached to many conclusions agreed in their essence upon that the related diversification has the major role in value maximization of a firm and the wealth of its owners .                       

View Publication Preview PDF
Crossref
Publication Date
Mon Jun 19 2023
Journal Name
Journal Of Engineering
Experimental Studies and Finite Element Modeling of Piles and Pile Groups in Dry Sand under Harmonic Excitation
...Show More Authors

Foundations supporting reciprocating engines, radar towers, turbines, large electric motors, and generators, etc. are subject to vibrations caused by unbalanced machine forces as well as the static weight of the machine. If these vibrations are excessive, they may damage the machine or cause it not to function properly. In the case of block foundation, if changes in size and mass of the foundation do not lead to a satisfactory design, a pile foundation may be used. In this study, the dynamic response of piles and pile Groups in dry sand is investigated experimentally. The analysis involves the displacement response under harmonic excitation. In addition, a numerical modeling by using finite element method with a three-dimensional formula

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Sat Oct 01 2022
Journal Name
Advances In Structural Engineering
Experimental and FE analysis of composite RC beams with encased pultruded GFRP I-beam under static loads
...Show More Authors

Publication Date
Fri Sep 15 2023
Journal Name
Journal Of Water Resources And Geosciences
Evaluation of Water and Wheat Productivity under Center Pivot Sprinkler Irrigation in Desert Soils/Holly Karbala Governorate
...Show More Authors

Two field experimسents were conducted in one of the fields of the Agriculture Division of Ain Al-Tamr /Holy Karbala Governorate at two sites of different textures during the agricultural season 2020/2021. The first site has sandy loam texture (gypsum soils). The second site has loamy sand texture (calcareous soils). The factors of the study included: The first factor included two types of soil, gypsum and calcareous soil. The second factor is the tillage systems (no-tillage, spring spike harrows, disc harrows, and mold board plow). The experiment was designed in the two study sites according to the RCBD with three replications. The Valley type center pivot irrigation system was evaluated before planting, three speeds, 30, 50 and 100% of th

... Show More
View Publication Preview PDF
Publication Date
Sat Oct 01 2022
Journal Name
Advances In Structural Engineering
Experimental and FE analysis of composite RC beams with encased pultruded GFRP I-beam under static loads
...Show More Authors

Encasing glass fiber reinforced polymer (GFRP) beam with reinforced concrete (RC) improves stability, prevents buckling of the web, and enhances the fire resistance efficiency. This paper provides experimental and numerical investigations on the flexural performance of RC specimens composite with encased pultruded GFRP I-sections. The effect of using shear studs to improve the composite interaction between the GFRP beam and concrete was explored. Three specimens were tested under three-point loading. The deformations, strains in the GFRP beams, and slippages between the GFRP beams and concrete were recorded. The embedded GFRP beam enhanced the peak loads by 65% and 51% for the composite specimens with and without shear connectors,

... Show More
View Publication
Crossref (24)
Clarivate Crossref
Publication Date
Tue Jun 21 2022
Journal Name
Peerj Computer Science
Performance evaluation of frequency division duplex (FDD) massive multiple input multiple output (MIMO) under different correlation models
...Show More Authors

Massive multiple-input multiple-output (massive-MIMO) is considered as the key technology to meet the huge demands of data rates in the future wireless communications networks. However, for massive-MIMO systems to realize their maximum potential gain, sufficiently accurate downlink (DL) channel state information (CSI) with low overhead to meet the short coherence time (CT) is required. Therefore, this article aims to overcome the technical challenge of DL CSI estimation in a frequency-division-duplex (FDD) massive-MIMO with short CT considering five different physical correlation models. To this end, the statistical structure of the massive-MIMO channel, which is captured by the physical correlation is exploited to find sufficiently

... Show More
View Publication
Scopus (5)
Crossref (5)
Scopus Clarivate Crossref