• Title/Summary/Keyword: jordan effect

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Utilizing vacuum bagging process to enhance bond strength between FRP sheets and concrete

  • Abdelal, Nisrin R.;Irshidat, Mohammad R.
    • Structural Engineering and Mechanics
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    • v.72 no.3
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    • pp.305-312
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    • 2019
  • This paper investigates the effect of utilizing vacuum bagging process to enhance the bond behavior between fiber reinforced polymer (FRP) composites and concrete substrate. Sixty specimens were prepared and tested using double-shear bond test. The effect of various parameters such as vacuum, fiber type, and FRP sheet length and width on the bond strength were investigated. The experimental results revealed that utilizing vacuum leads to improve the bond behavior between FRP composites and concrete. Both the ultimate bond forces and the maximum displacements were enhanced when applying the vacuum which leads to reduction in the amount of FRP materials needed to achieve the required bond strength compared with the un-vacuumed specimens. The efficiency of the enhancement in bond behavior due to vacuum highly depends on the fiber type; using carbon fiber showed higher enhancement in the bond strength compared to the glass fiber when vacuum was applied. On the contrary, specimens with glass fiber showed higher enhancement in the maximum slippage compared to specimens with carbon fibers. Utilizing vacuum does not affect the debonding failure modes but lead to increase in the amount of attached concrete on the surface of the debonded FRP sheet.

Finite element parametric study of RC beams strengthened with carbon nanotubes modified composites

  • Irshidat, Mohammad R.;Alhusban, Rami S.
    • Computers and Concrete
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    • v.27 no.2
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    • pp.131-141
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    • 2021
  • This paper aims at investigating the capability of different FRP/concrete interface models to predict the effect of carbon nanotubes on the flexural behavior of RC beams strengthened with CFRP. Three different interfacial bond models are proposed to simulate the adhesion between CFRP composites and concrete, namely: full bond, nonlinear spring element, and cohesive zone model. 3D Nonlinear finite element model is developed then validated using experimental work conducted by the authors in a previous investigation. Cohesive zone model (CZM) has the best agreement with the experimental results in terms of load-deflection response. CZM is the only bond model that accurately predicted the cracks patterns and failure mode of the strengthened RC beams. The FE model is then expanded to predict the effect of bond strength on the flexural capacity of RC beams strengthened with externally bonded CNTs modified CFRP composites using CZM bond model. The results reveal that the flexural capacity of the strengthened beams increases with increasing the bond strength value. However, only 23% and 22% of the CFRP stress and strain capacity; in the case of full bond; can be utilized before failure.

Influence of Varying Levels of Dietary Undegraded Intake Protein Intake on Nutrient Intake, Body Weight Change and Reproductive Parameters in Postpartum Awassi Ewes

  • Haddad, S.G.;Kridli, R.T.;Al-Wadi, D.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.5
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    • pp.637-642
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    • 2005
  • The objective of this study was to evaluate the effect of dietary undegradable protein (UP) level on body weight change, nutrient intake, milk production and postpartum reproductive performance of Awassi ewes. Twenty-seven multiparous Awassi ewes (initial body weight = 53.3${\pm}$1.6 kg) were randomly assigned to three dietary treatments (9 ewes/treatment) for 62 days using a completely randomized design. Experimental diets were isonitrogenous (15.5% CP), isocaloric, and were formulated to contain 17.9 (LUP), 27.1 (MUP), and 34.0% (HUP) of the dietary CP as UP. On day 10${\pm}$3 (day 0 = parturition) ewes were housed in individual pens for 5 weeks. Feed offered and refused was recorded daily. At the end of this period, animals were removed from their pens and combined into 3 separate groups (LUP, MUP and HUP). One fertile, harnessed ram was allowed with each group for 34 days. Rams were rotated every 2 days among the three groups. Each group was offered the corresponding experimental diet. Organic matter, CP, UP and metabolizable energy intakes were higher (p<0.05) for ewes fed the HUP diet compared with ewes fed the LUP and MUP diets. Ewes fed the HUP diet gained more (p<0.05) weight compared with ewes fed the MUP diet (7.3 vs. 2.1 kg), while ewes fed the LUP diet lost an average of 2.1 kg. Pregnancy rate of ewes fed the HUP diet was 100%, compared with 66 and 33% for ewes fed the MUP and LUP diets, respectively. Lambing rate was greater (p<0.05) for ewes fed HUP (8/9) diet compared with ewes fed the MUP (4/9) and LUP (3/9) diets. These results indicate that Awassi ewes receiving adequate dietary UP level consume more feed and are capable of returning to estrus shortly after parturition and are capable of producing two lamb crops per year.

Seasonal Changes of Water Properties and Current in the Northernmost Gulf of Aqaba, Red Sea

  • Manasrah, Riyad;Zibdah, Mohammad;Al-Ougaily, Firas;Yusuf, Najim;Al-Najjar, Tariq
    • Ocean Science Journal
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    • v.42 no.2
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    • pp.103-116
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    • 2007
  • Seasonal changes of tide signal(s), temperature, salinity and current were studied during the years 2004-2005 in the northernmost Gulf of Aqaba, which is under developmental activities, to obtain scientific bases for best management and sustainability. Spectrum analysis revealed permanent signals of tide measurements during all seasons, which represented semidiurnal and diurnal barotropic tides. The other signal periods of 8.13, 6.10-6.32, 4.16 and 1.02-1.05 h were not detected in all seasons, which were related to shallow water compound and overtides of principle solar and lunar constituent and to seiches generated in the Red Sea and the Gulf of Aqaba. Spatial and temporal distribution of temperature, salinity and density showed significant differences between months in the coastal and offshore region and no significant differences among the coastal sites, between the surface and bottom waters and between coastal and offshore waters. Therefore, the temporal and spatial variation of water properties in the northernmost Gulf of Aqaba behave similarly compared to other parts. The coastal current below 12 m depth was weak $(3-6\;cms^{-1})$ and fluctuated from east-northeastward to west-southwestward (parallel to the shoreline), which may be related to the effect of bottom topography and/or current density due to differential cooling between eastern and western parts in the study area, and wind-induced upwelling and downwelling in the eastern and western side, respectively. The prevailing northerly winds and stratification conditions during summer were the main causes of the southward current at 6 and 12 m depths with average speed of 28 and $12cms^{-1}$ respectively.

The Impact of Audit Quality on Tobin's Q: Evidence from Jordan

  • SHUBITA, Mohammad Fawzi
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.7
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    • pp.517-523
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    • 2021
  • Audit quality encompasses the key elements that create an environment that maximizes the likelihood that quality audits are performed consistently. This study aimed to identify the impact of auditing quality on the market value of the manufacturing companies listed on the Amman Stock Exchange (ASE). The analytical method was adopted in this research to extract and collect the necessary data. This study hypothesizes that audit quality leads to an increase in the market value by the offering of high-quality services. The study used the panel data approach to analyze cross-sectional data for 41 industrial companies that included time series data for the period (2019-2019). To test its hypotheses, the study used the fixed-effect model. The study found that the audit quality factors (audit office size, client retention period, auditor's fees, and linking with international audit offices) did not have a significant impact on market value. It found also the positive impact of the audit office size on the market value of the listed companies on the ASE for the period from 2009 to 2019. The study recommended the management of the company realize the importance of contracting with audit offices of large size and good reputation because these offices are more capable of increasing their efficiency, qualifying their employees, and thus be fully prepared for the audit process efficiently and effectively.

The Effect of Corporate Social Responsibility Disclosure on Market Performance: Evidence from Jordan

  • ZRAQAT, Omar;ZUREIGAT, Qasim;AL-RAWASHDEH, Hani Ali;OKOUR, Samer Mohammed;HUSSIEN, Lina Fuad;AL-BAWAB, Atef Aqeel
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.8
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    • pp.453-463
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    • 2021
  • The current study aims to investigate the relationship between CSRD and firm performance, as an indicator for corporate socially responsible behavior, and corporate market performance of listed companies on the Amman stock exchange (ASE). The study adopts a quantitative methodology and utilizes pooled data sets that was collected following content analysis approach of the annual reports for the period 2014 to 2019. The study sample consists of 42 listed companies. The study ran a multiple regression model in order to capture the relationship between the independent variable CSRD and the dependent variable that is Firm performance which was measured using Tobin's Q. The study also utilized five control variables in order to control the hypothesized relationship between CSRD and Firm Performance. The results indicate a negative but significant relationship between CSRD and corporate market performance measured by Tobin's Q. The results stand against the notion of the business case for CSR, and indicate the opposite position, so, the higher CSRD, the lower will be Tobin's Q. Such results support the notion of the institutional theory, and provide an initial evidence for legitimacy seeking behavior in Jordanian companies. However, the results indicate a lower level of awareness of CSR across investors and market players, which support arguments of the difference in market perceptions towards CSR.

Flexural behavior of RC beams made with basalt and polypropylene fibers: Experimental and numerical study

  • Murad, Yasmin Z.;Abdel-Jabar, Haneen
    • Computers and Concrete
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    • v.30 no.3
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    • pp.165-173
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    • 2022
  • The effect of basalt and polypropylene fibers on the flexural behavior of reinforced concrete (RC) beams is investigated in this paper. The compressive and tensile behaviors of the basalt concrete and polypropylene concrete cylinders are also investigated. Eight beams and 28 cylinders were made with different percentages of basalt and polypropylene fibers. The dosages of fiber were selected as 0.6%, 1.3%, and 2.5% of the total cement weight. Each type of fiber was mixed solely with the concrete mix. Basalt and polypropylene fibers are modern and cheap materials that can be used to improve the structural behavior of RC members. This research is designed to find the optimum percentage of basalt and polypropylene fibers for enhancing the flexural behavior of RC beams. Test results showed that the addition of basalt and polypropylene fibers in any dosage (0.6%, 1.3%, and 2.5%) can increase the flexural strength and displacement ductility index of the beams where the maximum enhancement was measured with 1.3% fibers. The maximum increments in the flexural strength and the displacement ductility index were 30.39% and 260% for the basalt fiber case, while the maximum improvement for the polypropylene fibers case was 55.5% and 230% compared to the control specimen. Finite element (FE) models were then developed in ABAQUS to predict the numerical behaviour of the tested beams. The FE models were able to predict the experimental behaviour with reasonable accuracy. This research confirms the efficiency of basalt and polypropylene fibers in enhancing the flexural behavior of RC beams, and it also suggests the optimum dosage of fibers.

Using Varying Levels of Formic Acid to Limit Growth of Salmonella gallinarum in Contaminated Broiler Feed

  • Al-Natour, Mohammad Q.;Alshawabkeh, Khalil M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.3
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    • pp.390-395
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    • 2005
  • Reported here are the effects of added formic acid on inhibitory effect of Salmonella gallinarum in poultry feed. Two experiments were conducted to investigate the viability of S. gallinarum and pH of poultry feed using different dietary formic acid levels (0.0, 0.5, 1.0 and 1.5%) on inhibitory effect of S. gallinarum in broiler feed. Experiment one was conducted to investigate the viability of S. gallinarum and pH of artificially contaminated diet at 0, 1, 3, 5 and 7 days after treatment in vitro. Formic acid showed a significant (p<0.05) reduction in the viability for all treatments with time after treatment. Various formic acid levels in vitro showed a reduction in the pH of the diet depending upon the concentration of treated acid, and the diet remained acidic below the growth range of S. gallinarum. This meant that the bacterial cells were exposed to stressful conditions that made them unable to grow. Experiment two was conducted to find out the effect of dietary formic acid levels on S. gallinarum colonization and pH in the contents of crop, small intestine, large intestine and ceca and mortality rate of broiler chicks at 7, 14 and 21 days of age when fed artificially contaminated diet with S. gallinarum. The numbers of S. gallinarum re-isolated from all treated groups except in groups treated with 0.5% formic acid, decreased significantly (p<0.05) compared with the control group. The treatment significantly (p<0.05) lowered the pH of the crop, small intestine, large intestine and ceca contents in all groups except the groups treated with 0.5% formic acid compared with the control. All treated groups showed a significant (p<0.05) reduction in overall mortality rate during the experimental period (3 to 21 days) compared with the control. The results indicate that addition of formic acid in a total concentration of 1.5% to the diet of newly hatched broiler chicks significantly decreases the contamination of diet with S. gallinarum.

The Impact of Board of Directors' Characteristics on Firm Performance: A Case Study in Jordan

  • KANAKRIYAH, Raed
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.3
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    • pp.341-350
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    • 2021
  • This study tested the effect of the board of directors' (BOD) characteristics on the corporate performance of the Jordanian industrial and service companies listed on the Amman Stock Exchange (ASE) during the period 2015-2019. The characteristics of the BOD were measured through the following variables: MO = managerial ownership; CEODU = CEO duality; BI = board independence; GD = gender diversity; ND = nationality diversity; AE = advanced education; BM = board meetings; BSIZ = board size; CSIZ = corporate size; CA = corporate age. The corporate performance was measured by return on assets (ROA) and return on equity (ROE). The corporate size and corporate age were used as control variables. The study sample consisted of 85 industrial and service companies with 425 observations to identify the nature of the effect of the BOD characteristics on performance. This study applied time-series data (panel data), and the multiple linear regression method was used to achieve study objectives. Results showed a positive effect of the study variables on performance, while the corporate age and the education level (BOD members) have a negative effect on performance.

Effect of Post Insemination Progesterone Supplement on Pregnancy Rates of Repeat Breeder Friesian Cows

  • Ababneh, Mohammed M.;Alnimer, Mufeed A.;Husein, Mustafa Q.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.11
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    • pp.1670-1676
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    • 2007
  • Fifty repeat breeder (RB) Friesian cows were allocated to five groups of 10 cows each, to determine the effect of progesterone (P4) supplement on P4 concentrations and pregnancy rates during the periods of corpus luteum (CL) formation and development between days 2-7 and 7-12 following a spontaneous or $PGF_{2{\alpha}}$-induced estrus. Cows were artificially inseminated during $PGF_{2{\alpha}}$-induced (PGF-P4-d2 and PGF-P4-d7 groups) or spontaneous (S-P4-d2, S-P4-d7, and control groups) estrus. Progesterone-releasing intravaginal device (PRID) devoid of estrogen capsule were inserted either on d 2 (PGF-P4-d2 and S-P4-d2 groups) or d 7 (PGF-P4-d7 and S-P4-d7 groups) post-insemination and left in place for 5 days. Control cows did not receive any treatment. Blood samples were collected for progesterone analysis from all cows once daily for 4 days starting on the day of estrus (d 0) and once every 3 days thereafter until d 22. Progesterone treatment by day interaction accounted for higher plasma P4 in treated than non-treated control cows. Progesterone concentrations differed significantly (p<0.05) during metestrus (d 2 to d 7) but not during diestrus (d 7 to d 12). $PGF_{2{\alpha}}$ treatment, lactation number, service number or their interactions did not affect progesterone concentrations and pregnancy rates. Therefore, cows were grouped according to the day of P4 supplement irrespective of the $PGF_{2{\alpha}}$ treatment. Progesterone supplement on d 7 but not d 2 significantly increased (p<0.03) pregnancy rates in repeat breeding cows with four or more previous services but not in cows in their third service. In conclusion, post-insemination P4 supplement to repeat breeding cows with four or more previous services improved pregnancy rates and should be advocated when no specific reason for infertility is diagnosed. Further studies with larger numbers of repeat breeding cows under field conditions are needed to ascertain the findings of this study.