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.
The aim for this research is to investigate the effect of inclusion of crack incidence into the 2D numerical model of the masonry units and bonding mortar on the behavior of unreinforced masonry walls supporting a loaded reinforced concrete slab. The finite element method was implemented for the modeling and analysis of unreinforced masonry walls. In this paper, ABAQUS, FE software with implicit solver was used to model and analyze unreinforced masonry walls which are subjected to a vertical load. Detailed Micro Modeling technique was used to model the masonry units, mortar and unit-mortar interface separately. It was found that considering potential pure tensional cracks located vertically in the middle of the mortar and units show
... Show More
(1)
(27)
(23)
(10)
(11)
The current paper aims to investigate the stress distribution developed in Kennedy Class II mandibular distal extension removable partial dentures due to applying a unilateral load condition in both vertical and lateral oblique directions. 3D models of mandible bone and RPD framework were first built based on actual patient data and later exported to ANSYS software to implement the numerical analysis. For realistic analysis, the model considered the frictional contact between the RPD retainers with the teeth and mucosa with the resin denture base by applying the feature of small sliding. To ensure maximum longevity and suitability of restoration, two different metallic RPDs constructed from commercially pure titanium (CP Ti) and cob
... Show More
(6)
(5)
Companies seek to enhance investor confidence by achieving the highest level of transparency in disclosure of financial and non-financial information (SASB standards) for Iraqi insurance companies listed on the financial market. The aim of the research is to identify the extent of the ability of financial and non-financial information to enhance transparency in reporting, which is reflected in Investor confidence. And the standards of sustainability development accounting issued by (SASB) through the electronic questionnaire that was distributed. Companies seek to achieve a set of goals, the most important of which is to enhance investor confidence by improving transparency in disclosure. Concerning the employment of financial an
... Show MoreOrganophosphorus insecticide and growth regulator namely Ethephon (2-chloroethylphosphonic acid) are widely used as a ripening process accelerator and a cultivation duration inhibitor. Pomegranate extract (PPE) has recently been taken into consideration due to its pharmacological effects especially those associated with renal diseases. Thus, this study aims to investigate the possible protective effect of PPE against ethephon-induced nephrotoxicity in rats. In this study four groups of adult male rats were divided into control group, PPE 400 mg/kg group, Ethephon 250 mg/kg group, and finally, PPE + Ethephon group (treated with the same dose of PPE group and Ethephon group). In the current study, kidney function parameters (KIM-1, creatin
... Show More
(3)
(2)
Airlift reactors are widely used in the chemical and biochemical applications as effective contactors for mass and heat transfer. The main advantages of airlift contactor compared with simple bubble column are ease of construction, low shear rate, high capacity, good mixing and liquid circulation without mechanical agitators and circulating pumps.
In this work, growth characteristics of Chlorella vulgaris microalgae were studied in an internal loop airlift photobioreactor for biomass production. The bioreactor operated under batch and semi-continuous culture mode using commercially available 20:20:20+TE NPK fertilizer as nutrients. The experiments were conducted to evaluate the growth rate and biomass productivity of
... Show Moreيهدف هذا البحث الى تصميم قائمة بمؤشرات القيم العلمية والاخلاقية التي ينبغي توافرها في محتوى كتاب الحاسوب للصف الثاني المتوسط، وتحليل محتوى الكتاب المذكور آنفاً وفقاً لها، وذلك عن طريق الإجابة عن السؤال الآتي: ما نسبة توافر القيم العلمية والأخلاقية في محتوى كتاب الحاسوب المُعد لطلبة الصف الثاني المتوسط الصادر من وزارة التربية العراقية/ المديرية العامة للمناهج في العام الدراسي ( 2017-2018) م؟ ولتحقيق هدفا البحث أ
... Show More
يهدف البحث الحالي إلى تحليل محتوى كتاب الحاسوب للصف الثاني متوسط وفق مهارات التفكير المنطقي للعام الدراسي(2015- 2016)م, ولتحقيق ذلك تم استخدام المنهج الوصفي التحليلي (تحليل محتوى) لملاءمته لطبيعة هدف البحث, وتم اعداد أداة البحث بالأعتماد على قائمة مهارات التفكير المنطقي بعد مراجعة الأدبيات والدراسات السابقة, وتم عرضها على مجموعة من المحكمين المتخصصين في المناهج وطرائق التدريس وعلم النفس وعلم الحاسبات والقياس
... Show Moreهدفت الدراسة الى تحليل محتوى كتاب الرياضيات للصف الاول متوسط على وفق مكونات المعرفة الرياضية (المفاهيم الرياضية , التعميمات الرياضية, المهارات الرياضية والمسائل الرياضية )
وتفرعت منه الاسئلة الاتية :
مانسبة المفاهيم الرياضية المتضمنة في كل فصل من فصول كتاب الرياضيات للصف الاول متوسط وللكتاب ككل ؟
مانسبة المهارات الرياضية المتضمنة في كل فص
... Show More