A real method of predication brake pad wear ,could lead to substantiol economies of time and money. This paper describes how such a procedure has been used and gives the results to establish is reliability by comparing the predicted wear with that which actually occurs in an existing service. The experimental work was carried out on three different commercial samples ,tested under different operation conditions (speed,load,time...etc)using a test ring especially modified for this purpose. Abrasive wear is mainly studied , since it is the type of wear that takes place in such arrangements. Samples wear tested in presences of sand or mud between the mating surfaces under different operational conditions of speed, load and braking time .Mechanical properties of the pad material samples (hardness, young,s modulus and collapse load under pure bending condition )wear established . The thermal conductivity and surface roughness of the pad material wear also found in order to enable comparison between the surface condition before and after testing. Sliding velocity had a small effect on the wear rate but it had great effect on friction coefficient. Wear rate was affected mainly by the surface temperature which causing a reduction friction coefficient and increasing the wear rate. Surface roughness had almost no effect on the wear rate since it was proved experimentally ,that the surface becomes softer during operation .mechanical properties of the pad material had fluctuating effect on wear rate. The existence of solid particles between pad and disc increasing wear rate and friction coefficient while the mud caused a reduction in wear rate of the pad surface since it acts as a lubricant absorbing the surface heat generated during sliding the area of contact between pad and disc. wear rate obtained experimentally agreed fairly well that found from empirically obtained equations.
The architecture Greek first civilizations, which focused on the design and planning of cities taking into account the percentages aesthetic and artistic forms beautiful and characterized Greek civilization styles three league and Ionian and Corinthian, has launched these names on this models relative to the form of
واقع الدراسات الاورومتوستطية في الجامعات العراقية "دراسة حالة كلية العلوم السياسية - جامعة بغداد"
ان هدف من هذا البحث هو تحليل محتوى كتاب الفيزياء للصف الرابع العلمي و المقرر تدريسه للعام الدراسي (2018-2017). ولتحقيق هذا الهدف، و بعد مراجعة الادب السابق في ضوء مفاهيم التنمية المستدامة، تم تطوير اداة تتضمن مفاهيم التنمية المستدامة وابعادها، حيث تكونت في صورتها النهائية من 51قضية فرعية موزعة بين المفاهيم الثلاثة الساسية: الاجتماعية، والاقتصادية، والبيئية .وبعد التأكد من صدق الاداة وثباتها، تم تحليل محتوى كتاب
... Show MoreThis research submitted to be a clear form for a city has famous civilization extended many centuries , made its obvious stamps & prominent for eyesight through what left us of edifices stated witnesses of Islamic cities , that are distinguished from others by its model , engineering of buildings that are taken special characteristics display thought creativity features & Islamic Arabian art , and this research clarifies from thought & design of Al-Hajjaj in building Wasit City that appeared as a result from the political conditions that Iraq faced them in general , and Al-Hajjaj in particular , the increasing of revolutions from different governorates
The institutions of higher education and scientific research are the strategic institutions in the field of investing the human resources.
Expenditure on such institutions is considered a long – term investment. Thus, the financial balancing in such institutions is not a traditional one.
These institutions are not for profit organizations.
Accordingly, they need to have accounting data that are calculated on an agreed upon cost basis due to the continuous growth in the expenditure on the services rendered by these institutions. These calls for the availability of tools that help rationalize the expenditure.
Cost Accounting system is capable of providing the useful data for such purposes an
... Show Moreركزت الدراسة على بيان مؤشرات التنمية الحديثة في جمهورية تنزانيا المتحدة مع بيان التحديات الداخلية والخارجية التي تواجهها والتي تعرقل استدامة هذه المؤشرات وتطورها بالشكل الذي يسمح لهذا البلد المحافظة على استقراره ،ومن ثم استمرار برامجه التنموية الشاملة المستدامة، وهذا الامر لا شك يتطلب مواجهة مستمرة وفاعلة للمعرقلات الاقتصادية والسياسية ومنظومة الفساد في اجهزة الدولة . وتوصلت الدراسة في مجمل نتائجها بان
... Show MoreDiode lasers are becoming popular in periodontal surgery due to their highly absorption by pigments such as melanin and hemoglobin their weak absorption by water and hydroxyapatite makes them safe to be used around dental hard tissues. Objective: The aim of the present study was to evaluate the efficiency of diode laser in performing gingivectomy in comparison to conventional scalpel technique in patients with chronic inflammatory enlargement. Materials and methods: Thirty patients were selected for this study. All of them required surgical treatment of gingival enlargements and were randomly divided into two groups: Control group (treated by scalpel and include sixteen patients) and study group (treated with diode laser 940nm and includ
... Show MoreOur research deals with the role of theatrical decoration in creating visual thumbs and the effect achieved as a result in the theatrical presentation in terms of supporting the idea of centralization of the dramatic construction of the show, as the researcher emphasizes that this topic has begun with a new horizon removed many technical concepts and knowledge in the theater.
Horizon knowledge and discoveries based on the structures of light and sight to achieve an existing transformation from steel to ethereal. According to these new concepts, systems other than those based on old methods of presentation have been formed.
In light of this, the researcher divided his research into:
First: the problem of research and the need fo
اهتم في الربع الأول بالمفاهيم النظرية للمناهج التي تقع في النقاط الخمس ، النقطة الأولى تتعلق بمفهوم الخطاب والخطاب المادي ، وقلنا أن الرسالة كانت مبنية على الجسد من البداية ، حتى قبل ذلك هناك ستكون فلسفة أو معرفة المنظمة. أما النقطة الثانية فتتعلق بالمفهوم الفينومينولوجي للخطاب ، ونحن في هذه المرحلة أهم الركائز التي قام عليها (إدموند هوسرل) في بناء مفهوم وصفي ضعيف. في النقطة الثالثة نكشف عن الظواهر المتعلقة ب
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