Previous experimental studies have suggested that hot mixed asphalt (HMA) concrete using hydrated lime (HL) to partially replace the conventional limestone dust filler at 2.5% by the total weight of all aggregates showed an optimum improvement on several key mechanical properties, fatigue life span and moisture susceptibility. However, so far, the knowledge of the thermal response of the modified asphalt concrete and thermal influence on the durability of the pavement constructed are still relatively limited but important to inform pavement design. This paper, at first, reports an experimental study of the tensile fatigue life of HMA concrete mixes designed for wearing layer application. Tests were conducted under three different temperatures for five mixes of different HL contents and one with no use of HL. On the experimental data, temperature effect on material fatigue was characterized in terms of the S-N curve modelling parameters. At last, numerical modelling, set at a climatic scenario in the UK, was performed to analyse and compare the seasonal climatic thermal influence on the fatigue life of two pavement structures using and not using the HL modified HMA concrete. Both the experiment and modelling have demonstrated that the 2.5% HL HMA concrete largely enhances the fatigue life of the material and the constructed pavement.
The drones have become the focus of researchers’ attention because they enter into many details of life. The Tri-copter was chosen because it combines the advantages of the quadcopter in stability and manoeuvrability quickly. In this paper, the nonlinear Tri-copter model is entirely derived and applied three controllers; Proportional-Integral-Derivative (PID), Fractional Order PID (FOPID), and Nonlinear PID (NLPID). The tuning process for the controllers’ parameters had been tuned by using the Grey Wolf Optimization (GWO) algorithm. Then the results obtained had been compared. Where the improvement rate for the Tri-copter model of the nonlinear controller (NLPID) if compared with
Pain is a sensory and emotional experience that is influenced by physiologic, sensory, affective, cognitive, socio-cultural and behavioral factors. Postoperative pain is the commonest reason for delayed discharge and unanticipated hospital admission after ambulatory surgery. Our Objective is to test the hypothesis that administration of 2 ml/kg/hr preoperative IV fluids may attenuates postoperative pain.The study was carried out in the Baghdad Teaching Hospital, Al-Yarmok Teaching Hospital and Al-Karama Teaching Hospital from 12 May till 17 June 2009. The total number of patients was 120 (35 males and 85 females) with their age ranged between 10-90 years. The patients were divided into two groups according to administration of preop
... Show MorePain is a sensory and emotional experience that is influenced by physiologic, sensory, affective, cognitive, socio-cultural and behavioral factors. Postoperative pain is the commonest reason for delayed discharge and unanticipated hospital admission after ambulatory surgery. Our Objective is to test the hypothesis that administration of 2 ml/kg/hr preoperative IV fluids may attenuates postoperative pain.The study was carried out in the Baghdad Teaching Hospital, Al-Yarmok Teaching Hospital and Al-Karama Teaching Hospital from 12 May till 17 June 2009. The total number of patients was 120 (35 males and 85 females) with their age ranged between 10-90 years. The patients were divided into two groups according to administration of preoperati
... Show MoreVacuum evaporation technique was used to prepare pure and doped ZnS:Pb thin films at10% atomic weight of Pb element onto glass substrates at room temperature for 200 nm thickness. Effect of doping on a.c electrical properties such as, a.c conductivity, real, and imaginary parts of dielectric constant within frequency range (10 KHz - 10 MHz) are measured. The frequency dependence of a.c conductivity is matched with correlated barrier hoping especially at higher frequency. Effect of doping on behavior of a.c mechanism within temperature range 298-473 K was studied.
In the present research, the chemical washing method has been selected using three chelating agents: citric acid, acetic acid and Ethylene Diamine Tetraacetic Acid (EDTA) to remove 137Cs from two different contaminated soil samples were classified as fine and coarse grained. The factors that affecting removal efficiency such as type of soil, mixing ratio and molarity have been investigated. The results revealed that no correlation relation was found between removal efficiency and the studied factors. The results also showed that conventional chemical washing method was not effective in removing 137Cs and that there are further studies still need to achieve this objective.
Orthodontic tooth movement is characterized by tissue reactions, which consist of an inflammatory response in periodontal ligament and followed by bone remodeling in the periodontium depending on the forces applied. These processes trigger the secretion of various proteins and enzymes into the saliva. The purpose of this study was to evaluate the activity of the lactate dehydrogenase (LDH) in saliva during orthodontic tooth movement using different magnitude of continuous orthodontic forces. Thirty orthodontic patients (12 males and 18 females) with ages 17-23 years with class II division I malocclusion all requiring bilateral maxillary first premolar extractions. Those patients were randomly divided into 3 groups according to the magnitude
... Show MoreStudy the effect of additives polymer polyvinyl alcohol (PVA) after solving in water by concentration 10% since represent a standard of PVA solution with added to cement – silica composite of ratio (1:2) with 5%, 10%, 15%, 20%, and 25% respectively to the standard quantity of water which using as a mortar of building. The results are demonstrate increasing on compression resistance with increase of PVA solution until 20%, and decreasing of thermal conductivity which represent a composite are increasing in thermal insulating. The results were recommended decreasing of water absorption with increase of PVA solution ratio as illustrated in this study.
In this study, Epoxy Resin plates was prepared by mixing epoxy(A) and hardner(B)with ratio(A:B) (3:1) with different thickness (0.3-0.96)cm. The effect of thickness on optical properties have been studied (absorption ,transmission ,reflectance) also the optical constant were found like (absorption coefficient, extenuation coefficient and refraction index) for all of the prepared plates. The results have shown that by increasing the thickness of plates., the absorption intensity increase in which at plates thickness (0.3-0.96)cm the absorption intensity were(1.54-1.43) respectively, and since absorption peak for epoxy occur in ultraviolet region and exactly at wavelength(368)nm and energy gap(Eg=3.05 eV) thus their good transmittance in the
... Show More