Micro metal forming has an application potential in different industrial fields. Flexible tool-assisted sheet metal forming at micro scale is among the forming techniques that have increasingly attracted wide attention of researchers. This forming process is a suitable technique for producing micro components because of its inexpensive process, high quality products and relatively high production rate. This study presents a novel micro deep drawing technique through using floating ring as an assistant die with flexible pad as a main die. The floating ring designed with specified geometry is located between the process workpiece and the rubber pad. The function of the floating ring in this work is to produce SS304 micro cups with profile radius precision as required as possible. The finite element simulations are accomplished using the commercial code Abaqus/Standard. In order to verify the simulation models, micro deep drawing experiments are carried out using a special set up developed specifically to meet the requirements of the simulations. The results revealed that the proposed technique is feasible to be adopted for producing micro cups with remarkable application capability in miniaturization technology.
Experimental study has been conducted for laminar natural convection heat transfer of air flow through a rectangular enclosure fitted with vertical partition. The partition was oriented parallel to the two vertical isothermal walls with different temperatures, while all the other surfaces of the enclosure were insulated. In this study a test rig has been designed and constructed to allow studying the effect of Rayleigh number, aperture height ratio, partition thickness, the position of aperture according to the side walls and according to the height, the position of the partition according to the hot wall, and partition inclination. The experiments were carried out with air as the working fluid for Rayleigh number range (5*107 – 1.3*10
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Irak’ın osmanlıcada yazılan sayısız elyazmalar çeşitli illerinde bulunur. Bunlardan Irak’ın başkenti olan Bağdat’tır. Irak Ulusal Müzesi Bağdad’ın uygarlık yerlerindendir. Elyazması Evi müzenin en önemli bölümleri sayılır. Orada osmanlıcada yazılan çok değerli elyazmalar bulunur. Bu elyazmalarından birisini ( fotokopi ) elde edip üzerinde çalışılmaktadır. Eser Antoloji şeklinde yazılmış. Bu eserden Sadullah Pâşâ’nın On Dokuzuncu Asır Manzumesini seçip ele alınmaktadır.
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... Show Moreلقد نشا علم التحقيق على ايدي المحدثين المسلمين الذين وضعوا قواعد هذا العلم وظهرت مؤلفات عدة في هذا المجال ، لكن ما قام به الاقدمون لم يشكل قواعد علم مستقل بذاته ومنذ ظهور الطباعة بدأت حركة تحقيق المخطوطات ، وتعددت مناهج التحقيق فكان للمستشرقين منهجهم الخاص وظهر منهج التحقيق والاخراج الفني والعلمي للمخطوط .
The deficit of the federal budget and the structural imbalances suffered by the Iraqi economy has affected the direction of research towards suggesting steps and mechanisms can be relied upon in the near term to form a broader base of non-oil revenues aimed at achieving a balanced budget, and to proceed to reform the financial situation, In reducing their financial dictates, whether capital or operational, which lead to significant financial and economic consequences. This also requires that the Iraqi political elite have the real will, strategic vision and full awareness that the implementation of these reforms has potential social and economic effects, with long-term measures to be taken. The aim is not only to reform the finan
... Show MoreIn this work, pure and copper mixed oxide PAni nanofiber thin films are successfully synthesized on silicon substrates by hydrothermal method and spin coating technique at room temperature with thickness of about 325 nm. The structural, surface morphological, optical and photoconductivity properties have been investigated. The XRD results showed that PAni films have crystalline nature, CuO and PAni/CuO nanostructure composites are monoclinic polycrystalline structure. The FESEM images of PAni clearly indicate that it has nanofiber-like structure, whereas the CuO film has spongelike shape. The surface morphology analysis of PAni/CuO composite shows that nanofiber caped with inorganic material which is CuO is a core-shell structure. Op
... Show MoreThin films of cadmium sulphoselenide (CdSSe) have been prepared by a thermal evaporation method on glass substrate, and with pressure of 4x10-5 mbar. The optical constants such as (refractive index n, dielectric constant ?i,r and Extinction coefficient ?) of the deposition films were obtained from the analysis of the experimental recorded transmittance spectral data. The optical band gap of (CdSSe) films is calculate from (?h?)2 vs. photon energy curve. CdSSe films have a direct energy gap, and the values of the energy gap were found to increase when increasing annealing temperature. The band gap of the films varies from 1.68 – 2.39 eV.
The objective of the research is to shed light on the nature of the impact of the activities of the national strategy for poverty alleviation in achieving the goals of sustainable development, and the research problem was represented by Is there an effect of the activities of the national strategy for poverty reduction in achieving the goals of sustainable development? and represents the field of research in the Ministry of Labor and Social Affairs For the years (2012-2016) and the results of the sustainable development goals indicators for the years (2012-2016), the ready-made statistical program (SPSS ver.10) was used to calculate the percentages, multiple linear regression equation, the F test and the R2 coefficient, and the research
... Show Morelarization modulation plays an important role in polarization encoding in quantum key distribution. By using polarization modulation, quantum key distribution systems become more compact and more vulnerable as one laser source is used instead of using multiple laser sources that may cause side-channel attacks. Metasurfaces with their exceptional optical properties have led to the development of versatile ultrathin optical devices. They are made up of planar arrays of resonant or nearly resonant subwavelength pieces and provide complete control over reflected and transmitted electromagnetic waves opening several possibilities for the development of innovative optical components. In this work, the Si nanowire metasurface
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The simulation of groundwater movement has been carried out by using MODFLOW model
in order to show the impact of change of water surface elevation of the Tigris river on layers of
the aquifer system for Nuclear Research Center at Al-Tuwaitha area, in addition to evaluate the
ability of the proposed pumping well to collect groundwater and change the direction of flow at
steady-state. The results of the study indicated that there is a good match between the values of
groundwater levels that calculated in the model and measured in the field, where mean error is
0.09 m.
The study also showed that the increasing of water surface elevation of the