Ti6Al4V alloy is widely used in aerospace and medical applications. It is classified as a difficult to machine material due to its low thermal conductivity and high chemical reactivity. In this study, hybrid intelligent models have been developed to predict surface roughness when end milling Ti6Al4V alloy with a Physical Vapor Deposition PVD coated tool under dry cutting conditions. Back propagation neural network (BPNN) has been hybridized with two heuristic optimization techniques, namely: gravitational search algorithm (GSA) and genetic algorithm (GA). Taguchi method was used with an L27 orthogonal array to generate 27 experiment runs. Design expert software was used to do analysis of variances (ANOVA). The experimental data were divided randomly into three subsets for training, validation, and testing the developed hybrid intelligent model. ANOVA results revealed that feed rate is highly affected by the surface roughness followed by the depth of cut. One-way ANOVA, including a Post-Hoc test, was used to evaluate the performance of three developed models. The hybrid model of Artificial Neural Network-Gravitational Search Algorithm (ANN-GSA) has outperformed Artificial Neural Network (ANN) and Artificial Neural Network-Genetic Algorithm (ANN-GA) models. ANN-GSA achieved minimum testing mean square error of 7.41 × 10−13 and a maximum R-value of 1. Further, its convergence speed was faster than ANN-GA. GSA proved its ability to improve the performance of BPNN, which suffers from local minima problems.
Laryngoscopy and tracheal intubation are considered the most invasive stimuli in anesthesia. They provoked cardiovascular responses that include hypertension, tachycardia and dysrhythmias. Various pharmacological approaches have been used to blunt or attenuate such pressor responses. The present study was designed to evaluate the effect of medazolom, lignocaine and propranolol as a valuable adjuvant to fentanyl in attenuating hemodynamic responses to endotracheal intubation in normotensive patients. Thirty two patient with physical status I or II according to the score of American Society of Anesthesiologist (ASA), scheduled for elective surgery under standard general anesthesia, were randomly allocated into four groups (8 patients in ea
... Show MoreBackground: This study aimed to find whether there is a relation between the mesio-distal crown diameters of the deciduous second molars and the permanent first molars in an Iraqi sample from Baghdad city. Material and methods: The sample consisted of 54 Iraqi children aged 8-9 years at the mixed dentition stage. The measurements included the mesio-distal crown width of the deciduous second molars and the permanent first molars on the study casts using digital sliding vernier. Results: The results revealed absence of the side difference of the widths of teeth measured. High significant gender difference was detected for the permanent first molars and the deciduous second molars except mandibular permanent first molar. On the other hand, hig
... Show MoreThe effect of compound machine on wheat "Tamuz cultivar" was studied based on some technical indicators which were tested under three practical speed (PS) of 2.015, 3.143, and 4.216 km.hr-1 and three tillage depth (TD) of 11, 13, and 15cm. The split-split plot arrangement in RCBD with three replications was used. The results showed that the PS of 2.015km.hr-1 was major best than other two speed in all studied conditions, physical properties (SBD and TSP), mechanical parameters (FD, (DP and LAS), and yield and growth parameters (PVI, BY and HI). The TD of 11cm was major effect to the other two levels TD of 13 and TD of 15cm in all studied conditions. All interactions were significant,
Language is a vehicle for social values and ideologies that a man intends or attempts to express. Dramatic texts are one of the discursive practices that embody values and ideologies. What is expressed in dramatic text is deliberate because it is meant to affect other’s values, trends and ideologies in one way or another. Such ideologies and values are not explicit. To bring them out requires putting language under scrutiny to unveil what is implied. The present study attempts to analyze a dramatic script entitled Advice to Iraqi Women by the British playwright Martin Crimp in an attempt to unveil the intended political ideologies underlying the text. The title reflects a political aspect embedded in the word “Iraqi” that
... Show MoreBackground: The longevity of any prosthesis depends on the materials from which it was fabricated, that is why, defects in the material properties may reduce the service life of prosthesis and necessitate its replacement. The aim of this study was to evaluate the effect of adding different concentrations of Polyamide-6 (Nylon-6) on the tear and tensile strength of A-2186 RTV silicone elastomer. Materials and Methods: 80 samples were fabricated by the addition of 0%, 1%, 3% and 5% by weight PA-6 micro-particles powder to A-2186 platinum RTV silicone elastomer. The study samples were divided into four (4) groups, each group containing 20 samples. One control group was prepared without PA-6 micro particles and three experimental groups were pr
... Show MoreResearch on the automated extraction of essential data from an electrocardiography (ECG) recording has been a significant topic for a long time. The main focus of digital processing processes is to measure fiducial points that determine the beginning and end of the P, QRS, and T waves based on their waveform properties. The presence of unavoidable noise during ECG data collection and inherent physiological differences among individuals make it challenging to accurately identify these reference points, resulting in suboptimal performance. This is done through several primary stages that rely on the idea of preliminary processing of the ECG electrical signal through a set of steps (preparing raw data and converting them into files tha
... Show MorePolymer metal complexes of poly ethylene glycol acetal and Ag (I), Cu (II), Ni (II), Mn (II), Co (III) and Hg (II) were prepared from the reaction of PEG with aldehyde derived from Erythro-ascorbic acid (pentulosono-ɣ-lactone-2, 3- enedianisoate). All these compounds were characterized by Thin Layer Chromatography (TLC) and FTIR spectra and aldehyde was also characterized by (U.V-Vis), 1HNMR,13CNMR, and mass spectra. It has been established that, the polymer and its metal complexes showed good activities against four pathogenic bacteria (Escherichia coli ,Klebsiellapneumonae, Staphylococcusaureus, Staphylococcus Albus) and two fungal (Aspergillus Niger,Yeast). The polymer metal complexes showed higher activity than the free polymer. The
... Show MoreThe study aimed to investigate the relationship between the multiple intelligence and the numerical sense. The chosen population of the study was the 4th secondary stage students. The sample consisted of 400 female and male student. The researcher utilized two test; multiple intelligence test which include three categories of intelligence (logical-mathematical, spatial, and linguistics) consisted of (36) item, and the numerical sense test that consisted of (44) item. The two tests were constructed by the researcher himself. The psychometric properties of the test were also verified. The results showed that there was a correlation between the multiple intelligence and the numerical sense as well as the students’ means scores
... Show MoreZusammenfassung: Das Drama " Minna von Barnhelm von Lessing ist ein weltbekannts Drama, das in verschiedene Sprachen übersetzt wurde. Es beschreibt die Schwierigkeiten eines Offiziers, der bestraft wurde. Er verlor seinen Job und auch seine Ehre. Minna ist seine Verlobte, die ihn suchte und auch neben ihm stehen wollte. Trotzdem sie ihm in einem Hotel zufällig begegnete, hatten die beide immer noch Probleme. Am Ende des Dramas könnten sie alle ihrer Probleme lösen und hatten schönes Ende.
Abstract:
Mina von Barnhelm is a German play written by the author ( Lessing ) , it's a well-known comedy play that was translated into many languages including Arabic language .
This play is about a