Burnishing improves fatigue strength, surface hardness and decrease surface roughness of metal because this process transforms tensile residual stresses into compressive residual stresses. Roller burnishing tool is used in the present work on low carbon steel (AISI 1008) specimens. In this work, different experiments were used to study the influence of feed parameter and speed parameter in burnishing process on fatigue strength, surface roughness and surface hardness of low carbon steel (AISI 1008) specimens. The first parameter used is feed values which were (0.6, 0.8, and 1) mm at constant speed (370) rpm, while the second parameter used is speed at values (540, 800 and 1200) rpm and at constant feed (1) mm. The results of the fatigue test showed that improvement in fatigue limit, where the highest fatigue limit was obtained at (1mm feed, 1200rpm speed) in burnishing process which was (169 Mpa). The hardness results, showed increasing feed and speed values lead to increasing the hardness. The burnishing process reduces surface roughness by producing accurate and better surface finish. The best surface fineness of metal at (1mm feed and 1200 rpm speed) was 0.11 μm.
Arab-Islamic architecture has undergone a change at multiple levels affected by modern technology, so the research sought to address the role of contemporary technologies on a fundamental and fundamental component of architecture, which is the architectural space, what is known as the essence of architecture and its ultimate destination, with a focus on the architectural space in the architecture of the contemporary Arab Islamic mosque, because the mosque’s architecture is so important in Islamic law and the belief of the Muslim person himself, where the mosque is the functional style produced by the Islamic faith and embodied in it, whereas, knowing the levels of influence of contemporary technologies in the architectural spac
... Show MoreThe researcher focused on the importance of the physical abilities of the tennis game, as this game is one of the games that are characterized by its specificity in performance as this game is characterized by continuous movement and dealing with different elements, so this game requires the development of muscle strength, which plays an important role in Performance skills in the game of tennis. There are several methods to develop strength, including flat hierarchical technique, which is one of the most common forms of training in the development of muscle strength. As for the research problem, the researcher found a method that has an effect on the development of force. Therefore, the researcher tried to diversify a
... Show MoreIn this research we been estimated the survival function for data suffer from the disturbances and confusion of Iraq Household Socio-Economic Survey: IHSES II 2012 , to data from a five-year age groups follow the distribution of the Generalized Gamma: GG. It had been used two methods for the purposes of estimating and fitting which is the way the Principle of Maximizing Entropy: POME, and method of booting to nonparametric smoothing function for Kernel, to overcome the mathematical problems plaguing integrals contained in this distribution in particular of the integration of the incomplete gamma function, along with the use of traditional way in which is the Maximum Likelihood: ML. Where the comparison on the basis of the method of the Cen
... Show MoreThe present paper addresses cultivation of Chlorella vulgaris microalgae using airlift photobioreactor that sparged with 5% CO2/air. The experimental data were compared with that obtained from bioreactor aerated with air and unsparged bioreactor. The results showed that the concentration of biomass is 0.36 g l-1 in sparged bioreactor with CO2/air, while, the concentration of biomass reached to 0.069 g l-1 in the unsparged bioreactor. They showed also that aerated bioreactor with CO2/air gives more biomass production even the bioreactor was aerated with air. This study proved that application of sparging system for cultivation of Chlorella vulgaris microalgae using either CO2/air mixture or air has a significant growth rate, since the biorea
... Show MoreThe study aims to reveal the degree of application of the alternative evaluation strategy in social studies in public education in the Kingdom of Saudi Arabia. It also aims to identify the opinions of experts on how to implement this. The study adopted the mixed methodology, which represented in the descriptive-analytical method, and qualitative methods through the grounded theory. The study used two tools namely: a questionnaire for assessments of social studies teachers and semi-structured interview questions. The results of the study showed a medium degree of appreciation for the application of alternative evaluation strategies by social studies teachers in general education with an average of (2.28). The results also showed that ther
... Show MoreZnS thin films were grown onto glass substrates by flash evaporation technique, the effects of ? – rays on the optical constants of ZnS these films were studied. It was found that ? – rays affected all the parameters under investigation.
The study investigated the behaviour of asphalt concrete mixes for aggregate gradations, according to the Iraqi specification using the Bailey method designed by an Excel spreadsheet. In mixing aggregates with varying gradations (coarse and fine aggregate), The Bailey method is a systematic methodology that offers aggregate interlocking as the backbone of the framework and a controlled gradation to complete the blends. Six types of gradation are used according to the bailey method considered in this study. Two-course prepared Asphalt Concrete Wearing and Asphalt Concrete binder, the Nominal Maximum Aggregate Sizes (NMAS) of the mixtures are 19 and 12.5 mm, respectively. The total number of specimens was 240 for both layers (15 samp
... Show MoreObjective(s): To evaluate primary health care services at primary health care centers in Baghdad City and to compare between these primary health care centers relative to such quality. Methodology: A descriptive design, using the evaluation approach, is study to Evaluation of quality of primary care services at primary health care centers in Baghdad City. A multistage probability sample of (36) health care centers was selected. The sample consists of (12) model centers, (12) urban centers, and (12) rural centers.A constructedquestionnaire is composed of (23) items. It consisted of (5) parts that include inta
Goal of research is to investigate the impact of the use of effective learning model in the collection of the fourth grade students/Department of physics in the material educational methods and the development of critical thinking .to teach this goal has been formulated hypothesis cefereeten zero subsidiary of the second hypothesis .To investigate the research hypothesis were selected sample of fourth-grade students of the department of physics at the univers
... Show MoreThe aim of the current study is to create special norms of the second edition of Minnesota multi faces personality inventory, and the fifth edition of the sixteen personality factor questionnaire of catel. To this end, the researcher applied the Minnesota multi faces personality inventory over a sample of (1646) secondary and university students as well as plenty of disorders. She also applied the sixteen personality factor questionnaire of catel on (4700) secondary and university students. SPSS tools were used to process data.