Corrosion behavior of aluminium in 0.6 mol. dm-3 NaCl solution in acidic medium 0.7 was investigated in the absence and presence of different concentrations of amino acid, methionine, as environmentally – friendly corrosion inhibitor over temperature range (293-308)K. The investigation involved electrochemical polarization method using potentiostatic technique and optical microscopy, the inhibition efficiency increased with an increase in inhibitor concentration but decreased with increase in temperature. Results showed that the inhibition occurs through adsorption of the inhibitor molecules on the metal surface and it was found to obey Langmuir adsorption isotherm. Some thermodynamic parameters ∆. and activation ener

ABSTRACT Background: One of the major problems of all ceramic restorations is their probable fracture against the occlusal forces. The objective of this in vitro study was to evaluate the effect of two gingival finishing lines (90°shoulder and deep chamfer) on the fracture resistance of full contour CAD/CAM and heat press all-ceramic crowns. Materials and Methods: Thirty two maxillary first premolars were prepared to receive full contour CAD/CAM (zolid) and heat press (Cergo Kiss) ceramic crowns using a special paralleling device (Parallel-A-Prep). The teeth were divided into four groups according to the type of finishing line prepared. Each crown was cemented to its corresponding tooth using self-etch, self-adhesive dual cure resin ceme

This  experiment  was carried  out to evaluate   the efficiency ·of growth regulator  (Match) and biotic pesticides  (Agerin) on the  pupa and adult stages of cotton  leaf worm Spodoptera littoral is {Boisd) that developed from  the  1 51 larval instar  fed on food treated with different concentration  of these pesticides for different' periods. Result  showed that their was a significant  decreases  in pupal period    pupal  weight, pupal   length,   abnonnal   growth   for   pupal   stage      .   A  significant decrease  in the em

First  instar  larvae    of  spiny  cottcn  boll  wonn   Earias insulana

(Bosid.)    were    Fed     on    different    concentrations    of    biological insecticides (Agerin) and growth  regulators (Match) for ( 5, 3 and one days) .The results showed  that Agerin at 1.5 giL caused   99.9 , 99.9. and  96.9  %  accumulative killing  percentages  while    0.5  g/L  of  this biological  insecticidt::s resulted  in  92.96 , 58.9 and 33.3% in the three periods  of  feeding  

Among many problems that reduced the performance of the network, especially Wide Area Network, congestion is one of these, which is caused when traffic request reaches or exceeds the available capacity of a route, resulting in blocking and less throughput per unit time. Congestion management attributes try to manage such cases. The work presented in this paper deals with an important issue that is the Quality of Service (QoS) techniques. QoS is the combination effect on service level, which locates the user's degree of contentment of the service. In this paper, packet schedulers (FIFO, WFQ, CQ and PQ) were implemented and evaluated under different applications with different priorities. The results show that WFQ scheduler gives acceptable r

In this paper, we proposed a hybrid control methodology using improved artificial potential field with modify cat swarm algorithm to path planning of decoupled multi-mobile robot in dynamic environment. The proposed method consists of two phase: in the first phase, Artificial Potential Field method (APF) is used to generate path for each one of robots and avoided static obstacles in environment, and improved this method to solve the local minimum problem by using A* algorithm with B-Spline curve while in the second phase, modify Cat Swarm Algorithm (CSA) is used to control collision that occurs among robots or between robot with movable obstacles by using two behaviour modes: seek mode and track mode. Experimental results show that the p

Abstract

            Rayleigh distribution is one of the important distributions used for analysis life time data, and has applications in reliability study and physical interpretations. This paper introduces four different methods to estimate the scale parameter, and also estimate reliability function; these methods are Maximum Likelihood, and Bayes and Modified Bayes, and Minimax estimator under squared error loss function, for the scale and reliability function of the generalized Rayleigh distribution are obtained. The comparison is done through simulation procedure, t

     The worldwide pandemic Coronavirus (Covid-19) is a new viral disease that spreads mostly through nasal discharge and saliva from the lips while coughing or sneezing. This highly infectious disease spreads quickly and can overwhelm healthcare systems if not controlled. However, the employment of machine learning algorithms to monitor analytical data has a substantial influence on the speed of decision-making in some government entities.        ML algorithms trained on labeled patients’ symptoms cannot discriminate between diverse types of diseases such as COVID-19. Cough, fever, headache, sore throat, and shortness of breath were common symptoms of many bacterial and viral diseases.

This research focused on the nu

This research has come out with that strategies made by Porter as generally strategies applicable to any size and type of economic units cannot be applied to many of the economic units in the world in generally and in Iraq especially not a lot of economic units have the resources and competencies that enable them to provide a unique product of its kind in the minds of customers and then adopt a differentiation strategy  and not a lot of economic units have the resources and competencies that make them the cost leader. Differentiators and cost leaders are minority in the world while not differentiators and not cost leaders are majority in the world.

The economic units are not differentiators and not c