Frictional heat is generated when the clutch starts to engag. As a result of this operation the surface temperature is increased rapidly due to the difference in speed between the driving and driven parts. The influence of the thickness of frictional facing on the distribution of the contact pressure of the multi-disc clutches has been investigated using a numerical approach (the finite element method). The analysis of contact problem has been carried out for a multiple disc dry clutch (piston, clutch discs, separators and pressure plate). The results present the distribution of the contact pressure on all tShe surfaces of friction discs that existed in the friction clutch system. Axisymmetric finite element models have been developed to accomplish the contact analysis in this work. Thickness of the frictional facing of a clutch disc is a significant parameter that affects the elastic and thermal behaviors of a dry friction clutch. The results proved that the magnitudes of the contact pressure are increased dramatically when the thickness of the friction facing decreases.
In the last decades, using mineral admixture in concrete became very necessary to improve concrete properties and reduce CO2 emissions associated with the cement production process. Subsequently, more sustainable concrete can be obtained. Ternary blended cement containing two different types of mineral admixture can achieve ambitious steps in this trend. In this research, the synergic effects of mineral admixtures in ternary blended cement and its effects on concrete fresh properties, strength, durability, and efficiency factors of mineral admixture in ternary blended cement, were reviewed. The main conclusion reached after reviewing many literature pieces is that the concrete with ternary blended cement
... Show MoreIn this work, a large part of Baghdad University campus has been selected. The determination of Geoidal height for the local area requires Ground Control Points which both Ellipsoidal and Orthometric heights are known to compute the difference between them. The first step of the leveling process began by selected the Ground Control Points (GCPs) around the area of the work, and then divided them into two groups of the network traverse stations. They were leveled and adjusted depend on the number of the Bench Marks (B.M.s). Total Station TS (Nikon Nivo 5C) and Global Positioning System (GPS-Garmin 78 map) are used to do this application. The aim of the proposed work was to determine the height of the Geoid surface in the study area. The Geoi
... Show MoreRisk identification and assessment can be analysed using many risk management tools. Fishbone diagram is one of these techniques which can be employed, for the identification of the causes behind the construction failure, which has become a phenomenon that often gets repeated in several projects. If these failures are not understood and handled scientifically, it may lead to disputes between the project parties. Additionally, the construction failure also leads to an increase in the project budget, which in turn causes a delay in the completion of the projects. Punching shear in reinforcement slab may be one of the reasons for construction failures. However, there are many doubts about other causes that lead to this failure as w
... Show MoreBanking institutions are considered one of development foundations,and they also performe active role in supporting national economey and itsinstitutions. Banks became diversed in their activities that specialized Banksbecame one of the constituents of developing work in any activity, especiallyin investiment sector .In view of the importance of insurance sector and thenecessity of developing its divices and its working instituments, studyinginsurance Banking reality became a necessity, because insurance Companies inIraq are suffering of weakness in the level of insurance service, in addition tothe existence of a problem in the relationship between Banks network andinsurance industry.So this research aims to define insurance reality; the
... Show MoreThe Catharanthus roseus plant was extracted and converted to nanoparticles in this work. The Soxhlet method was used to extract alkaloid compounds from the Catharanthus roseus plant and converted them to the nanoscale. Chitosan polymer was used as a linking material and converted to Chitosan nanoparticles (CSNPs). The extracted alkaloids were linked with Chitosan nanoparticles by maleic anhydride to get the final product (CSNPs-Linker-alkaloids). The pure Chitosan, Chitosan nanoparticles, and CSNPs-Linker-alkaloids were characterized by X-ray diffractometer, and Fourier Transform Infrared spectroscopy. X-ray results show that all samples have an orthorhombic structure with crystallite size in nanodimensions. FTIR spectra prove that
... Show MoreThis researchable paper aims to focus of the role & mechanism of market makers in Iraqi stock market through analyzing its role in other Arabian as well as global stock ones, especially in current period through activate the use of bonds, shares, and trying to create a continued price balance. Then decreasing the opportunity having gaps between highest and lowest level without reasonable causes. In addition trying to deactivate the common decision without supported information. Moreover, this paper aims to explain the rules of increasing liquidity and having balance to lead the market into positive direction. Thus, for achieving the above-mentioned requirements, such conditions should be underlined by market makers as well as t
... Show MoreIt is well known that the spread of cancer or tumor growth increases in polluted environments. In this paper, the dynamic behavior of the cancer model in the polluted environment is studied taking into consideration the delay in clearance of the environment from their contamination. The set of differential equations that simulates this epidemic model is formulated. The existence, uniqueness, and the bound of the solution are discussed. The local and global stability conditions of disease-free and endemic equilibrium points are investigated. The occurrence of the Hopf bifurcation around the endemic equilibrium point is proved. The stability and direction of the periodic dynamics are studied. Finally, the paper is ended with a numerical simul
... Show MoreThe problem of research is to identify the uses of Iraqi women for Facebook and the motives of these uses and the innovations that have been achieved from them, in view of the increasing role-played by social networking sites in the lives of individuals in general and women in particular.The research seeks to identify the following: Identify the extent to which Iraqi women use Facebook and the usage motives and innovations achieved by the interviewees When they using Facebook. This study belongs to the descriptive studies that are interested in monitoring the characteristics of a particular phenomenon to identify its characteristics and characteristics.This study adopted the survey methodology to test the hypotheses of the study and how
... Show MoreThe present study represent the histological and histochemical structure of the esophagus of laughing dove Streptopelia senegalensis, one of the wild birds, which feed on the seeds( grainvorous).The result showed that the esophagus long tubular quit wide and highly distensible organ situated at the right side of the nick , lie between pharynx and stomach it was divided into cervical and thoracic part , the cervical part longer than the thoracic part, and the crop was merely enlargement fusiform in shape which located at the entrance of the thorax. Esophagus parts showed that composed of four layer ;the mucosa, sub mucosa, muscular and adventitia or serosa, the mucosal layer was arranged in folds which was longer in the c
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