A tungsten inert gas (TIG) welding is one of the most popular kinds of welding used to join metals mainly for aluminum alloys.  However, many challenges may be met with this kind of joining process; these challenges arise from decay of mechanical properties of welded materials. In the present study, an attempt was made to enhancing the mechanical properties of TIG weld joint of 6061-T6 aluminum alloy by hardening the surfaces using shoot peening technique. To optimize the shoot peening process three times of exposure (5, 10, and 15) min. was used. All peened and unpeened, and welded and unwelded samples were  characterized by metallographic test to indicate the phase transformation and modification in microstructure occurring during welding process. Tensile test and Vickers micro-hardness measurements were performed for all samples to investigate the effect of shoot peening on mechanical properties of welded aluminum.
The results indicated a significant improvement in properties for peened welded and unwelded samples compared with those unpeened one. Also, the results showed that the tensile and microhardness properties were increased with increasing the time of exposure to 15 min. due to generation of compressive residual stresses at surface.
  
The first section of this research discussed the manner of the research from many sides like the problem it faces, importance of it , its targets ,boundaries, the way to collect and get information's and its assumption.
When the second chapter discussed the press – manufacturing and the development ,importance and types of newspapers, also its merits and weaknesses.
The third chapter talked about the scientific side and how to choose an assumption for the research . as it talked also about the apparent honest and stability tests that help in analyzing the research until getting results and so the right assumption for the research will be chosen.
And finally, the fourth chapter put highlight on the be
... Show Morethe power of the federal supreme court to stop the implementation of the law
This research focuses on the field of theatrical production, and focuses on the semantic displacement of the sign in the visual formation of the theater show, so the research has been entitled: "The semantic displacement of the sign and the visual formation of the postmodern theater ". Its importance is to illustrate the aesthetics produced by the semantic displacement of the theatrical sign and it is specialized in postmodern theater. The purpose of the research can be delimited to revealing the aesthetic work of the semantic displacement of the sign and the visual formation in the postmodern theatre. The study temporal boundary is 2017 and the capital of Baghdad is its spatial boundaries. The research sample was "Striptease
... Show MoreThis paper discuses the mindset contribution of the organization Science in organizational effectiveness (OE), and the most valuable thoughts they introduced in this subject, starting from the pre- classical era, through classical era to present time. This paper has identified the main contribution in OE. The concept of OE didn’t arise until what had been introduced by Chester Barnard, although Max Weber mentioned this concept in his bureaucratic theory, but he didn’t explain it as Barnard does. After that no clear focus was pointed to this subject until Peter Drucker did so, which considered as the main participant in OE after Barnard. After that many researchers be interested in OE and they start studying this subject like
... Show Moreبناء على ما تقدم يتضح ان القطاع العام والقطاع الخاص ليسا موقفا ايدولوجيا انتقائيا، وانما هو انبثاق من العمود الفقري للصيرورة الرأسمالية القائمة على تقديس الملكية الخاصة، وان الادوار التي يمكن ان يلعباها ليسا منعزلين عن الحركة العامة للاقتصاد في كليته، وليس هما ابنا السياسات الاقتصادية، والبناء الفوقي بقدر ماهما نتاج الحركة الموضوعية وصيرورة التطور الاجتماعي معبرا عنها في تطور علاقات الانتاج وقوى الانتا
... Show MoreThe aim of this research is controlling the amount of the robotic hand catching force using the artificial muscle wire as an actuator to achieve the desired response of the robotic hand in order to catch different things without destroying or dropping them; where the process is to be similar to that of human hand catching way. The proper selection of the amount of the catching force is achieved through out simulation using the fuzzy control technique. The mechanism of the arrangement of the muscle wires is proposed to achieve good force selections. The results indicate the feasibility of using this proposed technique which mimics human reasoning where as the weight of the caught peace increases, the force increases also with approximatel
... Show MoreThe aim of this study is to identify the effect of enabling the effectiveness of the work of the audit committees in private commercial banks and to identify the extent of awareness of the importance of empowerment in the work of these committees, especially as it is known that these committees, especially the inspection committees that go to private banks and from various sources including committees of the Central Bank of Iraq Committees of the Securities Commission and finally committees of the external audit offices, through an analysis of the determinants of empowerment in the performance of the most important work of the audit committees, namely: supervising the process of preparing reports, supervising the system of intern
... Show MoreAbstract
This study aims to evaluated the user satisfaction of retrieval services
concerning to universities thesis and dissertations in university dissertation
unit of Baghdad Library for achieving the following objectives:
1- Evaluating the performance of this unit (thesis unit of Baghdad University
Library) regarding to users opinion.
2- Recognizing the reasons in this unit behind the case of non satisfaction of
its users and trying to find the suitable solutions.
To achieve those two objectives, the questionnaire tool was performed
and determined the user's satisfaction level by using a sample survey. 1118
graduated students were subjected to this experiment. The following main
results were appeared:<
The acceptance sampling plans for generalized exponential distribution, when life time experiment is truncated at a pre-determined time are provided in this article. The two parameters (α, λ), (Scale parameters and Shape parameters) are estimated by LSE, WLSE and the Best Estimator’s for various samples sizes are used to find the ratio of true mean time to a pre-determined, and are used to find the smallest possible sample size required to ensure the producer’s risks, with a pre-fixed probability (1 - P*). The result of estimations and of sampling plans is provided in tables.
Key words: Generalized Exponential Distribution, Acceptance Sampling Plan, and Consumer’s and Producer Risks
... Show More