العقيدة الدينية وأثرها على منهج التفكير السياسي للولايات المتحدة الامريكية
Britain found itself at the end of the nineteenth century in front of many obstacles within Europe, it is to hold the coalition Russian Franco in 1894, and what form of threat to the interests of Britain in its colonies outside Europe, as well as the development of other European countries in military and economic aspects such as Germany and the United States and others. As she was defying the fleet of Britain, Germany, and the last has a naval fleet was able to protect all the way Britain and its colonies throughout the nineteenth century
In this work the effect of choosing tri-circular tube section had been addressed to minimize the end effector’s error, a comparison had been made between the tri-tube section and the traditional square cross section for a robot arm, the study shows that for the same weight of square section and tri-tube section the error may be reduced by about 33%.
A program had been built up by the use of MathCAD software to calculate the minimum weight of a square section robot arm that could with stand a given pay load and gives a minimum deflection. The second part of the program makes an optimization process for the dimension of the cross section and gives the dimensions of the tri-circular tube cross section that have the same weight of
... Show MoreElectrochemical Grinding (ECG) process is a mechanically assisted electrochemical process for material processing. The process is able to successfully machine electrically conducting harder materials at faster rate with improved surface finish and dimensional control. This research studies the effect of applied current, electrolyte concentration, spindle speed and the gap between workpiece and tool on hardness and material removal rate during electrochemical grinding for stainless steel 316. The characteristic features of the electrochemical grinding process are explored through Taguchi-design-based experimental studies. The better hardness can be obtained at 10 A of the current, 150 g/l of the electrolyte concentration, 0.3 mm of gap an
... Show MoreIn the present work experiments were conducted to study the effect of solid loading (1,5 and 9 vol.%) on the enhancement of carbon dioxide absorption in bubble column at various volumetric gas flow rate (0.75, 1 and 1.5 m3/h) and absorbent concentration (caustic soda)( 0.1,0.5 and 1 M ). Activated carbon and alumina oxide (Al2O3) are used as solid particles. The Danckwerts method was used to calculate interfacial area and individual mass transfer coefficients during absorption of carbon dioxide in a bubble column. The results show that the absorption rate was increased with increasing volumetric gas flow rate, caustic soda concentration and solid loading. Mass transfer coefficient and interfac
... Show MoreThe effect of solution heat treatment on the mechanical properties of Aluminum-Copper alloy. (2024-T3) by the rolling process is investigated. The solution heat treatment was implemented by heating the sheets to 480 C° and quenching them by water; then forming by rolling for many passes. And then natural aging is done for one month. Mechanical properties (tensile strength and hardness) are evaluated and the results are compared with the metal without treatment during the rolling process. ANSYS analysis is used to show the stresses distribution in the sheet during the rolling process. It has been seen that good mechanical properties are evident in the alloy without heat treatment due to the strain hardening and also the mechanical
... Show MoreCrocidolomia binotalis (Cb) (Zeller) is one of the main pests of cabbage which is difficult for farmers to control in the Ijen Crater in Indonesia. The demand for cabbage in Indonesia is increasing every year, so intensification efforts are continuously being made. Farmers intensively use synthetic pesticides as the primary control of Cb. The purpose of this study is to examine several control agents that can be used as an alternative to synthetic pesticides. Then, it provides recommendations to Ijen Crater farmers to adapt in reducing the use of synthetic pesticides. The biopesticide used was based on the Nuclear Polyhedrosis Virus strains of Spodoptera litura (SlNPV) and Helicoverpa armigera (HaNPV), botanical pesticides, and
... Show MoreMost studies indicated that the values of atmospheric variables have changed from their general rates due to pollution or global warming etc. Hence, the research indicates the changes of direct solar radiation values over a whole century i.e. from 1900 to 2000 depending on registered data for four cities, namely (Mosul - Baghdad - Rutba - Basra. Moreover, attemptsto correlate the direct solar radiation with the temperature values have been recorded over that period. The results showed that there is a decreasing pattern of radiation quantities over time throughout the study period, where the value of direct radiation over the city of Baghdad 5550 w/m2 was recorded in the year 1900, but this ratio decreased cle
... Show MoreIn this paper, a theoretical study to the effect of journal misalignment on the static characteristics of oil filled porous journal bearing when lubricated with couple stress fluid has been carried out.
The analytical model used through this work is for a bearing with isotropic permeability. Considering isotropic permeability the Reynolds' equation for the oil film is modified to include a so – called filter term and the effect of fluid coupled stress. The pressure equation for the porous medium is obtained from Darcy's law and continuity equation. The equation which was used to evaluate the oil film thickness was modified to include the effect of possible misalignment in longitudinal and transverse directions. The governing eq
... Show MoreObjective: The study aimed to identify the adolescents' fast foods and snacks, and find out the relationship between fast
food, snacks and adolescents' demographic data (gender and Body Mass Index). Methodology: A descriptive study
was conducted on impact of fast foods and snacks upon adolescents' Body Mass Index in secondary schools at Baghdad
city, starting from 20
th of April 2013 to the end of October 2014. Non- probability (purposive) sample of 1254
adolescents were chosen from secondary schools of both sides of Al-Karkh and Al-Russafa sectors. Data was collected
through a specially constructed questionnaire format include (12) items multiple choice questions. The validity of the
questionnaire was determined thr
Abstract
This study investigates the mechanical compression properties of tin-lead and lead-free alloy spherical balls, using more than 500 samples to identify statistical variability in the properties in each alloy. Isothermal aging was done to study and compare the aging effect on the microstructure and properties.
The results showed significant elastic and plastic anisotropy of tin phase in lead-free tin based solder and that was compared with simulation using a Crystal Plasticity Finite Element (CPEF) method that has the anisotropy of Sn installed. The results and experiments were in good agreement, indicating the range of values expected with anisotropic properties.
Keywords<
... Show More