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 method binery logistic regression and linear discrimint function of the most important statistical methods used in the classification and prediction when the data of the kind of binery (0,1) you can not use the normal regression therefore resort to binary logistic regression and linear discriminant function in the case of two group in the case of a Multicollinearity problem between the data (the data containing high correlation) It became not possible to use binary logistic regression and linear discriminant function, to solve this problem, we resort to Partial least square regression.
In this, search the comparison between binary lo
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Abstract:
This research aims to the importance of oil in achieving economic
security in the Arab. Oil is not an ordinary subject and returns it significance to
the followings:
1. The importance of skipping a source of energy.
2. The importance of oil as raw material for petrochemical industry.
3. The importance of the oil sector as an area of foreign investment
4. The importance of oil in the marketing activities, transport, insurance
and various services
In addition to the importance of oil in general and the Arab oil has
additional strategic advantages such as geographic location, And the
magnitude of reserves and production of heavy investment costs are relatively
simple, And the ability to meet the
The aim of this investigation is to study and analysis the role of governance in the evaluation of the and social performance of the economic units to be addressed through the concept of corporate governance and then to the social performance and its relationship to corporate governance.
The most important obtained results from this research is that the corporate governance of extreme importance, and derive their importance from being an essential tool to contribute to the transparency and fair disclosure of the financial results of economic units in the fight against financial and administrative corruption in economic units, thus providing protection and confidence of all parties, and the evaluating soci
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Abstract
The goal of the research is to diagnose some of the negative phenomena which was discovered through the period from (2010 to 2014) as determined by the national strategy to eliminate the corruption which was set out by the joint council of the corruption elimination in Iraq. And to measure the gap in applying the legal rules by the administration, concerning the misconducts and felonies upon the state employments made by the state employee and how far they are applied in the studied sample and to show the nature of the rules and their importance and their role when they are applied in scientific and expertise manner. And to encourage the offices of the general supervisors to adhere to them which will lead t
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Abstract This research deals with the definition of the concept of nodal purposes, And what is related to it, from its aim and importance, And for the purposes of the importance of Streptococcus In trying to understand the nodal truths For different minds, Especially with those who object to the introduction of belief in purposes studies, This research has two requirements: The first requirement: the concept and the aim of contractual purposes,It consists of two branches, The first is in the concept of nodal purposes, And it dealt with the definitions in terms of language and terminology And what we see is proportional to what aim |
The objective of this study was to develop neural network algorithm, (Multilayer Perceptron), based correlations for the prediction overall volumetric mass-transfer coefficient (kLa), in slurry bubble column for gas-liquid-solid systems. The Multilayer Perceptron is a novel technique based on the feature generation approach using back propagation neural network. Measurements of overall volumetric mass transfer coefficient were made with the air - Water, air - Glycerin and air - Alcohol systems as the liquid phase in bubble column of 0.15 m diameter. For operation with gas velocity in the range 0-20 cm/sec, the overall volumetric mass transfer coefficient was found to decrease w
... Show MoreSince 1990 internal combustion engines and variable systems has been considered as emission. Noise can be defined as undesirable sound, and in high levels it can be considered ahealth hazard. Large internal combustion engines produce high levels of noise. In many countries there are laws restricting the noise levels in large engine rooms and fixed applications. Locomotives engines have the minimum emission influence because of noise control techniques capability.
In this paper study on a single cylinder internal combustion engine was conducted. The engine works by adding ethanol to gasoline, at variable speeds, without adding ethanol, and with adding 10 and 20% ethanol in volumetric ratio. Using one sound insulator or two or with
... Show MoreThe role of the climate in the development of the performance of the administrative bodies of sports clubs
Human witnessed over the centuries many of the important issues faced by the international community was centered on human rights in general and the persecution of refugees, especially according to many forms may be directly or indirectly leaves behind economic crises, social and humanitarian push world countries to rethink the mechanisms and the feasibility of developing agreements and laws and the role of international and regional organizations to protect peoplerefugeestatus.
The investment environment is the incubator for all types of domestic and foreign investments, so if their determinants are encouraging, they increase the levels of investment flows and vice versa, as there is a relationship between the nature of the investment environment and the level of investment flows, and the determinants of the investment environment are numerous and the most important of which are security and political stability, and economic and financial factors that include relative stability In the exchange rate and inflation rates, the availability of banks and their development, transparency and integrity in administrative dealings and the lack of prevalence of administrative and financial corruption, and the clari
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