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.
يتناول البحث جزئية من جزئيات موضوع الفسخ المبتسر للعقد
السياسة الخارجية الاسرائيلية تجاه افريقيا بعد انتهاء الحرب الباردة (دراسة حالة اثيوبيا)
جمعت 50 حية مائية Natrix tessellata على وجبتين الأولى 25 حية عند فصل الربيع تحديدا من منتصف آذار الى منتصف نيسان، اما المجموعة الثانية ، 25 حية لفصل الصيف من منتصف حزيران الى منتصف تموز. اذ عزلت الذكور عن الإناث و حللت قطع من لحم الذكر و قطع من
لم يعد تقييم شركات الاعمال يعتمد على ربحيتها فحسب، ولم تعد تلك الشركات تعتمد في بناء سمعتها على مراكزها المالية فقط، فقد ظهرت مفاهيم حديثة تساعد على خلق بيئة عمل قادرة على التعامل مع التطورات المتسارعة في الجوانب الاقتصادية والتكنولوجية والإدارية عبر أنحاء العالم. وكان من أبرز هذه المفاهيم مفهوم "المسؤولية الاجتماعية للشركات" والتسويق الاخضر او المواطنة التسويقية او التسويق البيئي . وقد أصبح دور مؤسسات ال
... Show Moreتعرض الاقتصاد العراقي إلى صدمات نقدية شديدة بسبب الظروف السياسية والاقتصادية غير المستقرة والمتمثلة بشكل أساسي لخوض العراق حرب طويلة الأمد مع إيران في الثمانينات وحربين مدمرتين مع الولايات المتحدة الأمريكية فضلاً عن فرض الحصار الاقتصادي طيلة ثلاثة عشر عاما ً .
وتهدف هذه الدراسة إلى قياس وتحليل الصدمات النقدية التي تعرض لها الاقتصاد العراقي في فترة الثمانينات والتسعينات وبداية هذا القر
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Resumen
La literatura española tiene muchísimos de los grandes personajes y las figuras literarias que casi todos desempeñaron de una forma u otra un eficaz e importante papel en el desarrollo de la literatura española en particular y la literatura universal en general, entre otros podemos mencionar el gran escritor de origen argentino Jorge Luis Borges sobre el mismo gira este trabajo de investigación.
Sinceramente, podemos decir que el objetivo principal de ese trabajo de investigación es hacer conocer de una forma tan sencilla, tan simple y tan clara al lector público quién es Jorge Luis Borges quien procedía de una familia de próceres
... Show MoreSimulation Study
Abstract :
Robust statistics Known as, Resistance to mistakes resulting of the deviation of Check hypotheses of statistical properties ( Adjacent Unbiased , The Efficiency of data taken from a wide range of probability distributions follow a normal distribution or a mixture of other distributions with different standard deviations.
power spectrum function lead to, President role in the analysis of Stationary random processes, organized according to time, may be discrete random variables or continuous. Measuring its total capacity as frequency function.
Estimation methods Share with
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Since the early ages, scientists have been keen on the second source of Islamic law, namely the hadith of the Prophet. They also took from the less disciplined narrators, but they chose from their conversations a selection, and for this some prominent narrators who can be considered that Ibn Habban has been hardened to weaken them. Narrators who avoided Ibn Habban novel They are not true because Ibn Habban neglected her and left her to hurt some narrators who are confident in themselves
There is no doubt that the project control function is very important for administration, so the project Management depends on to monitor and control the project. The project control integrated to the planning which is the base of the administration functions; planning, organizing, directing, and controlling. Without project control cannot be insure to fulfill the plan of the project by the budget and specified time. The project management apply many methods of control to achieve the goals of project which are cost, time, and required specifications. Earned Value Management one of control methods that used in the project by international companies.
Earned Value Method is used in the project o
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