This paper develops a nonlinear transient three-dimensional heat transfer finite element model and a rate independent three-dimensional deformation model, developed for the CO2 laser welding simulations in Al-6061-T6 alloy. Simulations are performed using an indirect coupled thermal-structural method for the process of welding. Temperature-dependent thermal properties of Al-6061-T6, effect of latent heat of fusion, and the convective and radiative boundary conditions are included in the model. The heat input to the model is assumed to be a Gaussian heat source. The finite element code ANSYS12, along with a few FORTRAN subroutines, are employed to obtain the numerical results. The benefit of the proposed methodology is that it offers the capability of optimizing laser welding process, and also provides a reliable estimation of the developed temperatures, as well as the thermal stress (residual stress) and strain fields reducing the experimental effort.
To ascertain the stability or instability of time series, three versions of the model proposed by Dickie-Voller were used in this paper. The aim of this study is to explain the extent of the impact of some economic variables such as the supply of money, gross domestic product, national income, after reaching the stability of these variables. The results show that the variable money supply, the GDP variable, and the exchange rate variable were all stable at the level of the first difference in the time series. This means that the series is an integrated first-class series. Hence, the gross fixed capital formation variable, the variable national income, and the variable interest rate
... Show MoreNowadays, internet security is a critical concern; the One of the most difficult study issues in network security is "intrusion detection". Fight against external threats. Intrusion detection is a novel method of securing computers and data networks that are already in use. To boost the efficacy of intrusion detection systems, machine learning and deep learning are widely deployed. While work on intrusion detection systems is already underway, based on data mining and machine learning is effective, it requires to detect intrusions by training static batch classifiers regardless considering the time-varying features of a regular data stream. Real-world problems, on the other hand, rarely fit into models that have such constraints. Furthermor
... Show MoreNew series of metal ions complexes have been prepared from the new ligand 1,5- Dimethyl-4- (5-oxohexan-2- ylideneamino) -2-phenyl- 1H-pyrazol-3 (2H)-one derived from 2,5-hexandione and 4-aminophenazone. Then, its V(IV), Ni(II), Cu(II), Pd(II), Re(V) and Pt(IV) complexes prepared. The compounds have been characterized by FT-IR, UV-Vis, mass and 1H and 13C-NMR spectra, TGA curve, magnetic moment, elemental microanalyses (C.H.N.O.), chloride containing, Atomic absorption and molar conductance. Hyper Chem-8 program has been used to predict structural geometries of compounds in gas phase, the heat of formation, (binding, total and electronic energy) and dipole moment at 298 K.
This work represents the set of measurements of radon and thoron concentrations levels of soil-gas in Al-Kufa city in Iraq using electric Radon meter (RAD-7). Radon and thoron concentration were measured in soil-gas in 20 location for three depth of (50, 100 and 150) cm.
The results show that the emanation rate of radon and thoron gas varied from location to anther, depending on the geological formation. The Radon concentration in soil has been found to vary from (12775±400) Bq/m3 at 150 cm depth in location (sample K2) to (41.45±17) Bq/m3, for depth 150 cm in location (sample K20). The thoron concentration in soil has been found to vary from (198±8.5) Bq/m3 at 150 cm depth in location samples (K1 & K2) to undetected in the mos
Abstract Background: This study is aimed to assess the maxillary incisors’ root position, angulation, and buccal alveolar bone thickness in both genders and different classes of malocclusion using cone‑beam computed tomography (CBCT). Materials and Methods: Two hundred and six CBCT images were gathered and analyzed by three‑dimensional On‑Demand software to measure the variables of 803 maxillary central and lateral incisors. Genders and class difference was determined by unpaired t‑test, one‑way ANOVA, and Chi‑square tests. Results: Buccal root position of the maxillary incisors accounted for in the majority of the cases followed by the middle and palatal positions. The thickness of alveolar bone appears to have nearly the sam
... Show Moreيهدف هذا البحث إلى تحليل محتوى كتابي الحاسوب للمرحلة الإعدادية في جمهورية العراق وفقاً للتفكير المنطقي، واتبعت الباحثة منهج البحث الوصفي التحليلي، وتم توظيف أداة تحليل المحتوى، التي صُمِّمت وفقاً للعمليات العقلية المتضمنة في التفكير المنطقي بحسب العالم بياجيه ( Piaget )، واعتماد وحدة الفكرة (الصريحة) في عملية التحليل. تبين من نتائج هذا البحث أنَّ نسبة تضمين مهارات التفكير المنطقي في محتوى كتابي الحاسوب للمرحل
... Show Moreيهدف هذا البحث إلى تحليل محتوى كتابي الحاسوب للمرحلة المتوسطة في العراق وفقاً لعمليات العلم عن طريق الإجابة عن السؤال الآتي: ما نسبة توافر عمليات العلم في محتوى كتابي الحاسوب المقرران على طلبة المرحلة المتوسطة المعتمدان من وزارة التربية العراقية/ المديرية العامة للمناهج في العام الدراسي ( 2016-2017) م؟ اعتمد هذا البحث المنهج الوصفي التحليلي، وتضمن مجتمع البحث وعينته محتوى كتابي الحاسوب المقررين لطلبة الصفين
... Show MoreEnglish ابحث عن مقالات و مجلات ... تحليل علاقة ثقافة المنظمة بلازمة من منظور الفردبة - الجماعية أ.د زكـريا مطلك الدوري، أ.د سـعـد علي العـنزي، أ. يعرب عدنان السعيدي مجلة كلية بغداد للعلوم الاقتصادية الجامعة 2009, المجلد 2, العدد 20, الصفحات 107-122 الخلاصة تتعدد وجهات النظر بشأن الاسباب والمعالجات الممكنة للازمات، وان هذا الاختلاف يرجع بالاصل إلى تنوع المداخل التي يعتمد عليها الباحثين في تناول الظاهرة أو الموضوع. وضمن هذا
... Show MoreTurkman literature is regarded as a branch of the general Turkish literarure. The title Turman literature began to be used after 1918, and this remained under the influence of classical Turkishliterature till the beginning of the twentieth century. The best poets who repreesented this type are Hijri Dada, Khidir Lütfi, Mohammad Sadiq, Othman Mathloom and others…
In this study I followed the method of Professor Doctor Mohammad Kaplan (Ph.D) and Professor Doctor Nurullah Çetin(Ph.D) in analysing the poetical design. In this study I tried to analyse the poem entitled Taliim (My Fate) by the poet Khidir Lütfi and the poet Othman mathloom who wrote a poem wi
... Show More