The durability of asphalt pavement is associated with the properties and performance of the binder. This work-study intended to understand the impact of blending Styrene-Butadiene-Styrene (SBS) to conventional asphalt concrete mixtures and calculating the Optimum Asphalt Content (OAC) for conventional mixture also; compare the performance between SBS modified with the conventional mixture. Two different kinds of asphalt penetration grades, A.C. (40-50) and A.C. (60-70), were improved with 2.5 and 3.5% SBS polymer, respectively. Marshall properties were determined in this work. Optimum Asphalt Content (OAC) was 4.93 and 5.1% by weight of mixture for A.C. (40-50) and (60-70), respectively. Marshall properties results show an increasement in the stability value by 8.65 and 20.19% for A.C. (40-50) with 2.5 and 3.5% of SBS, respectively. And an increasement by 9.32 and 20.61% for AC (60-70) with 2.5 and 3.5% of SBS respectively. Furthermore, the results indicate a decrease in Marshall flow by 14.7 and 26.47% for A.C. (40-50) with 2.5 and 3.5% SBS respectively and a decrease by 10.46 and 21.21% for A.C. (60-70) with 2.5 and 3.5% SBS respectively. Other Marshall properties were also calculated. Moreover, Blending SBS polymers to conventional asphalt mixtures produces a better performance to asphalt binder and better Marshall properties, which provides a great solution to Iraqi road problems affected by temperature and high traffic load, including less maintenance. Doi: 10.28991/cej-2021-03091709 Full Text: PDF
This field experiment, was conducted to investigate a comparison of two methods for harvesting potatoes: mechanical and handy when using moldboard and chisel plow for primary tillage and three different distances for planting tubers in the rows 15, 25, and 35 cm in silt clay loam soil south of Baghdad. The factorial experiment followed a randomized complete block design with three replications using L.S.D. 5 % and 1 %. Mechanical harvest recorded the best valid potato tubers at 88.78 %, marketable yield of 31.74 ton. ha-1, efficiency lifted 95.68 %, tubers damage index 28.41, speeding up the harvesting process and reducing time and effort. Handy harvest gave the least damage to potato tubers, 6.02 %, and unlifted potato tubers, 4.32 %. Howe
... Show MoreMultimedia applications impose different QoS requirements (e.g., bounded end-to-end delay and jitter) and need an enhanced transport layer protocol that should handle packet loss, minimize errors, manage network congestion, and transmit efficiently. Across an IP network, the transport layer protocol provides data transmission and affects the QoS provided to the application on hand. The most common transport layer protocols used by Internet applications are TCP and UDP. There are also advanced transport layer protocols such as DCCP and TFRC. The authors evaluated the performance of UDP, DCCP, SCTP, and TFRC over wired networks for three traffic flows: data transmission, video streaming, and voice over IP. The evaluation criteria were thro
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Abstract
The aim of the research is to clarify the requirements of the qualification of the external auditor in Iraq and the extent of their impact on the quality of the professional performance of the audit process. The research was based on analyzing the results of the questionnaire prepared for the impact of qualifications on the quality of professional performance. The researcher has reached a number of conclusions, the most important of which is that a highly qualified and unethical auditor has a greater negative impact on the quality of professional performance than those with low qualifications. The most important recommendations of the research were the need to pay
... Show MoreIn the present study, pure Poly(viny1 alcohol) (PVA) and pyromellitic dianhydride (PMDA) cross linked PVA with (0,5,10,15 and 20)wt.% and doped with different molarity (5,9)M of sulfuric acid (H2SO4) were prepared by the solution casting method and were characterized as a function of frequency in the range (1-100) KHz.
The FT-IR results showed that the strong broad band observed at 3738.05 and 3857.63 cm-1 may be assigned to O-H stretching due to the strong hydrogen bond of intramolecular and intermolecular type in PVA film. When PVA is doped with 5M and 9M H2SO4, a new peak was noticed at 813 cm-1, this peak may be due to the fo
... Show MoreMishrif Formation is the main reservoir in Amara Oil Field. It is divided into three units (MA, TZ1, and MB12). Geological model is important to build reservoir model that was built by Petrel -2009. FZI method was used to determine relationship between porosity and permeability for core data and permeability values for the uncored interval for Mishrif formation. A reservoir simulation model was adopted in this study using Eclipse 100. In this model, production history matching executed by production data for (AM1, AM4) wells since 2001 to 2015. Four different prediction cases have been suggested in the future performance of Mishrif reservoir for ten years extending from June 2015 to June 2025. The comparison has been mad
... Show MoreThe body of the actor and its expressive significance is an essential topic in studying acting . it is not only confined to the study of soul and body from philosophical aesthetic perspective , but also to study the conception and mechanism of such a dichotomy followed by theatre directors and theorists , who are highly concerned with the creativity of actors . The researchers believe that such a study would be of benefit for actors as well as others working in theatre .
The study falls into two sections . the first deals with the phi
... Show MoreAddress the intellectual controversy nature of the gap of knowledge and the strategic performance gap. The researcher start off from this intellectual controversy to seek to test the nature of the relationship and impact between them across a sample of (61) academics in the colleges of business and economics at the universities in Baghdad ,as the more specialized in the fields of knowledge and the strategic performance, The researcher is attain to the existence of relationship and impact of knowledge gap in strategic performance gap, the research included four axes first went to the methodology and second to theoretical frame and the third to view and analyze the results and test hypotheses while the fourth was devoted to the con
... Show MoreThermal performance of closed wet cooling tower has been investigated experimentally and theoretically
in this work. The theoretical model based on heat and mass transfer equations and heat and mass transfer balance equations which are established for steady state case. A new small indirect cooling tower was used for conducting experiments. The cooling capacity of cooling tower is 1 kW for an inlet water temperature of 38oC, a water mass velocity 2.3 kg/m2.s and an air wet bulb temperature of 26oC. This study investigates the relationship between saturation efficiency, cooling capacity and coefficient of performance of closed wet cooling tower versus different operating parameters such wet-bulb temperature, variable air-spray water fl