A series of laboratory model tests has been carried out to investigate the using of pomegranate sticks mat as reinforcement to increase the bearing capacity of footing on loose sand. The influence of depth and length of pomegranate sticks layer was examined. In the present research single layer of pomegranate sticks reinforcement was used to strengthen the loose sand stratum beneath the strip footing. The dimensions of the used foundation were 4*20 cm. The reinforcement layer has been embedded at depth 2, 4 and 8 cm under surcharge stresses . Reinforcing layer with length of 8 and 16 cm were used. The final model test results indicated that the inclusion of pomegranate sticks reinforcement is very effective in improvement the loading capacity of loose sand. The optimal
benefit in bearing capacity value was realized as the (D/B) ratio (embedded depth to footing width) equal to 0.5.The bearing capacity of a reinforced soil with single layer of pomegranate sticks at (D/B) ratio of o.5 increased by about 4 times (corresponding to S/B =10%) than that for the unreinforced case and continuous in increasing beyond that with no failure. The improvement in bearing capacity decreased with increasing depth of embedment of reinforcement layer until reach to a specified point in which the bearing capacity of a reinforced soil approximately identical with the case of no reinforcement. Also it was found that increase the length of pomegranate sticks layer has no beneficial effect on the improved the bearing capacity of loose sand.
The aim of this work is to explore the thermal performance of a tracked tubular solar still (TSS) with a parabolic trough concentrator in Baghdad (33.27° N, 44.37° E) in September 2022. The present tubular still is distinguished by its hexagonal glass cover. The effect of integrating the TSS with a heat pipe, the still tilt angle (10°, 15°), and the depth of saline water inside the still partitions on the productivity of freshwater are investigated. The results showed that using heat pipe enhances the freshwater productivity by 25%–40% and the efficiency by 25%. For the still integrated with heat pipe, as the water depth is increased from 5.5 to 6.5 cm the productivity of freshwater is incre
In the geotechnical and terramechanical engineering applications, precise understandings are yet to be established on the off-road structures interacting with complex soil profiles. Several theoretical and experimental approaches have been used to measure the ultimate bearing capacity of the layered soil, but with a significant level of differences depending on the failure mechanisms assumed. Furthermore, local displacement fields in layered soils are not yet studied well. Here, the bearing capacity of a dense sand layer overlying loose sand beneath a rigid beam is studied under the plain-strain condition. The study employs using digital particle image velocimetry (DPIV) and finite element method (FEM) simulations. In the FEM, an experiment
... Show MoreA condense study was done to compare between the ordinary estimators. In particular the maximum likelihood estimator and the robust estimator, to estimate the parameters of the mixed model of order one, namely ARMA(1,1) model.
Simulation study was done for a varieties the model. using: small, moderate and large sample sizes, were some new results were obtained. MAPE was used as a statistical criterion for comparison.
In this paper we estimate the coefficients and scale parameter in linear regression model depending on the residuals are of type 1 of extreme value distribution for the largest values . This can be regard as an improvement for the studies with the smallest values . We study two estimation methods ( OLS & MLE ) where we resort to Newton – Raphson (NR) and Fisher Scoring methods to get MLE estimate because the difficulty of using the usual approach with MLE . The relative efficiency criterion is considered beside to the statistical inference procedures for the extreme value regression model of type 1 for largest values . Confidence interval , hypothesis testing for both scale parameter and regression coefficients
... Show MoreIn this paper new methods were presented based on technique of differences which is the difference- based modified jackknifed generalized ridge regression estimator(DMJGR) and difference-based generalized jackknifed ridge regression estimator(DGJR), in estimating the parameters of linear part of the partially linear model. As for the nonlinear part represented by the nonparametric function, it was estimated using Nadaraya Watson smoother. The partially linear model was compared using these proposed methods with other estimators based on differencing technique through the MSE comparison criterion in simulation study.
Purpose: clarify the integrative relationship of strategic leadership skills and effective management and the role of those skills combined or individually in achieving effective management.
Research design: The researchers used the quantitative method by surveying a class sample from the heads of the executive departments in a group of Iraqi private banks, consisting of (106) individuals according to the (VUCA Prime) methodology for effective management and the ten skills model for Johansen. The questionnaire was analyzed using a model of the structural equation.
Findings: The most prominent results of the research were the presence of a weak ro
... Show MoreNowadays, most of the on-chip plasmonic single-photon sources emit an unpolarized stream of single photons that demand a subsequent polarizer stage in a practical quantum cryptography system. In this paper, we numerically demonstrated the coupling of the light emitted from a quantum emitter (QE) at 700 nm wavelength to the propagation mode supported by an on-chip hybrid plasmonic waveguide (HPW) polarization rotator. Our results proved that the light emitted is linearly polarized at 0º, 45º/−45º, and 90º with propagation lengths of 5 μm, 3.3 μm, and 3.9 μm, respectively. Moreover, high power-conversion efficiency was obtained from an applied transverse magnetic (TM) mode (0º-polarization) to a transverse electric (TE) (90º-polari
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Typological analysis about the negation marker in different languages is one of the fields of research that has attracted much attention. In Persian language, this constituent has been analysed from different aspects. This study aimed to analyse different aspects of negation marker in the adjectives, the noun phrases and the verb phrases based on typological analysis. Many studies have been revealed that the negation in adjectives has shown lexically and morphologically. In the noun phrases, /hich/ has used as a negative marker necessarily marking the verb phrase as negative too. In the verb phrases, negation occurs morphologically by the addition of the prefix /n
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