In the present investigation two different types of fiber reinforced polymer composites were prepared by hand lay-up method using three different parameters (curing temperature, pressing load and fiber volume fraction). These composites were prepared from the polyester resin as the matrix material reinforced with glass fibers as first group of samples and mat Kevlar fibers as the second group, both with different volume fractions (4%, 8%, and 12%) of fibers. They were then tested by tensile strength and impact strength. The main objective in this study is to use Taguchi method for predicting the better parameters that give the better tensile and impact strength to the composites, and then preparing composites at these parameters and comparing them with the randomly used once. The experimental and analytical results showed that the Taguchi method was successful in optimizing the parameters that give the highest properties and it can find the most influential parameter regardless of the material used. Also it showed that the volume fraction was the most influential parameter on the tensile and impact strength. The difference between these composites was in the properties values and that the Kevlar composites have higher tensile and impact strength.
Abstract:
If we neglect the value of historical fashions as a source of inspiration for
contemporary fashion designers we will neglect a treasure of original designs.
In neglecting such a treasure how could we then know what is original. Today
the most famous fashion designers are often inspired, in the outwardly from
and internal lines of their fashions, by fashion designed during the ages of the
past.
Designers can find such fashions in books of history and museums. But
the historical ages are not equal in the fertility of the originality and novelty of
their fashions. Thus the contemporary designer may not find the old designs
inspiring so he invents them.
The researcher was keen in this paper to inclu
The research aims at identifying the importance of scientific research for researchers and in creating new knowledge، development and utilization of mental and cognitive energies and developed them with the ability to research، extrapolation، meditation and then conclusion. The information was collected by interviewing the Secretary-General of the Central Library and by distributing questionnaire forms to the (33) teaching staff of the College of Higher Education. The responses of the society were analyzed the result and the recommendations were the most important 1. Information specialist and all employees of the administrators and technicians in the centers of information sources (libraries) and in the field are considered scientific r
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Precision is one of the main elements that control the quality of a geodetic network, which defines as the measure of the network efficiency in propagation of random errors. This research aims to solve ZOD and FOD problems for a geodetic network using Rosenbrock Method to optimize the geodetic networks by using MATLAB programming language, to find the optimal design of geodetic network with high precision. ZOD problem was applied to a case study network consists of 19 points and 58 designed distances with a priori deviation equal to 5mm, to determine the best points in the network to consider as control points. The results showed that P55 and P73 having the minimum ellipse of error and considered as control points. FOD problem was applie
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Staphylococcus aureus and Pseudomonas aeruginosa are the major globally distributed pathogens, which causes chronic and recalcitrant infections due to their capacity to produce biofilms in large part. Biofilm production represents a survival strategy in these species, allowing them to endure environmental stress by altering their gene expression to match their own survival needs. In this study, we co-cultured different clinical isolates of S. aureus and P. aeruginosa as mono- and mixed-species biofilms in a full-strength Brain Heart Infusion Broth (BHI) and in a 1000-fold diluted Brain Heart Infusion Broth (BHI/1000) using Microtiter plate assay and determination of colony-forming units. Furthermore, the effect of starvation stress on the e
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The work concerned with studying the effect of (SiO2) addition as a
filler on the adhesive properties of (PVA). Samples were prepared as
sheets by using casting method. The mechanical properties showed
that increase in tensile strength from (34MPa) to (68MPa) when
(SiO2) added to (PVA). The adhesive strength showed that joint
properties depend upon specific adhesive characteristic of material
(PVA) and (SiO2\PVA)composites at different concentrations (1.5%,
2.5%, 3.5%, 4.5wt%), the cohesive strength of the adhesive material,
the joint design, and adherent type (Sponge Rubber(SR), Natural
leather (NL), Vulcanized Rubber(VR), and Cartoon). The results
proved the tensile strength increased with (SiO2) ratio, so
ي لا ماق ثحبلا فادهأ قيقحتلو ثحبلا ةنيعل نايبتسا ءارجاو فراصملل ةيلاملا مئاوقلا ليلحتب ثحاب اهمهأ ناك تاجاتنتسا ىلإ ثحابلا لصوت دقو لإ صاخ معد دوجو مدع نم ةيفرصملا رطاخملا ةراد ةروصب اهدوجو مدعو فراصملل ةماعلا تارادلاا يف اهدوجو رصتقي ثيح ،ايلعلا تاهجلا لبق نم ديزي امم ،عورفلا يف ةلاعف مدع ةجيتن عورفلا نم ةدلوتملاو فراصملا اههجاوت يتلا رطاخملا اهمهأ ناك تايصوت ىلإ ثحابلا لصوت دقو امك ،ةيفرصملا تلاماعم
... Show MoreIn today's world the role of leadership in the control factors of the organization different and advancement, and that the possession of the human ability to the development and creation and innovation varies from one individual to another depending on experience; and levels of performance and intellectual; and his mental and physical and other such factors can create a kind of differentiation between the built humans, and this distinction creates our leaders are able to influence others and have the wisdom and connect active individuals and organizations. as the need for organizations of all sizes and levels of leadership transformation is an urgent need to link the application of the various plans and strategies device which direction
... Show MoreCapital is a property bank is very important, because it is part of the liquidity in the bank, which is a line of defense in the bank and secured against any losses that may be exposed to the banks, and in the case of low value of any item of the assets and the lack of a dedicated absorb the decline, while play a key role to some extent in the financing of fixed assets and in particular the relative importance of fixed assets is relatively small compared to the size of bank assets. &n
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