E-learning adoption in higher education in Jordan: vision, reality and change

This paper discusses the implementation of an e-learning program at a Jordanian University (Al-Ahliyya Amman University). The program originally aimed to establish a virtual university which offers totally online courses but due to a number of reasons there had to be some changes in the implementation process. The paper discusses such changes and challenges faced by AAU in implementing its e-learning program from an IS project management point of view. Findings suggest that implementing such projects needs careful consideration of a variety of issues to ensure that the objectives are achieved. The case provides rich insights to other educational institutions wishing to implement such projects

Fracture Toughness and Micro-Strain of Y-TZP Nanoceramics at Different Sintering Temperature

الهدف من هذا البحث هو دراسة تاثير درجة حرارة التلبيد على الخواص الميكانيكية و الانفعال المرن للزركونيا المثبتة باليتريا النانوية. حيث تم تلبيد العينات المكبوسة عند درجات (1500 – 1550 – 1600م⁰) في الهواء لمدة ساعتين , ثم بعد التلبيد تم صقلها لغرض اجراء فحص الصلادة المايكروية و لفحص متانة الكسر بواسطة جهاز فكرز (من 60 كغم الى 100غم). تم استخدام جهاز المجهر الذري  لايجاد التغير في حجم و شكل الحبيبات في العينات , و تم فحصها بواسطة الاشعة السينية لتحديد نوع الطور الناتج و لتحديد قيمة الانفعال المايكروي للعينات. لقد بينت النتائج انه عند زيادة درجة التلبيد سوف يزداد الحجم الحبيبي مع زيادة الانفعال المايكروي. ان الطور السائد الناتج بعد التلبيد هو الطورالرباعي , مع زيادة ابعاد المشبك نتيجة للانفعال المرن , و مع زيادة درجة التلبيد تزداد الصلادة المايكروية مع زيادة متانة الكسر.  The objective of this research is to study the effect of sintering temperature on the mechanical properties and micro-strain of yttria tetragonal zirconia polycrystalls (Y-TZP) nanostructure.   Where green disk formed by uniaxially press, sintered at (1500 – 1550 – 1600⁰C) in air for 2hr then polished to mirror shape for fracture toughness and micro-hardness measurement by Vickers indenter at (60 kg to 100gm) loads. Atomic force microscopy (AFM) technique was use to measure the change in grain size and shape of the samples, X-ray diffraction (XRD) evaluated to identify the phases and to measure the micro-strain of the samples.          The Results show that increasing sintering temperature will increase the grain size with increasing the average of micro-strain. Tetragonal  phase is the prevailing phase with small amount of cubic phase and the amount of monoclinic phase was under detection limite after sintering but there is increas in lattice dimension according to micro-strain calculation and grinding process produce micro-strain. With increasing the sintering temperature micro-hardness and fracture toughness will increas

Image Formation Free Rotation in Triple Pole-Piece Magnetic Lenses

Present work is mainly concern with the mathematical function, considered to represent the axial magnetic flux density distributions of proposed triple pole-pieces magnetic lenses which is used as rotation free lenses. This function has, in fact, three-optimization parameters. The only important parameter is the bore radius of the lens in the proposed model. This parameter can be affect on the projector properties of the lens, when the other two optimization parameters (maximum value of flux density and lens length) are constants, where the literature survey proved that unaffected on the lens properties. Results have clearly shown that the optimization parameter for current function, have a considerable effect on the lens distortion, lens magnification, and the reconstructed pole-pieces. Furthermore, the results obviously show the excellent ability for converting the form of the chosen mathematical function in order to represent the magnetic field of triple pole-pieces lenses. Keywords: Electron Optics, Projector Lens, Distortion, Magnificatio

A Shortest Data Window Algorithm for Detecting the Power Factor in presence of non-sinusoidal load current

During recent years, nonlinear power electronic equipments introduce harmonic pollution on electric power systems. It makes the traditional power factor meter can not act accurately when it monitors unbalanced and harmonic loads. In this paper, a new algorithm for detecting the power factor in presence of non-sinusoidal load current is proposed. The proposed algorithm detects the true power factor exactly. By uses only two successive sampled data points of the voltage and the current for each displacement power factor value calculation and two sampled data points for each distortion power factor value calculation, the total/true power factor becomes easy to measure using these values directly. The proposed detector implemented using microcontroller as a main part and has been tested for single phase power system. The test results show that it can measure the true power factor of the loads quickly and accurately

Comparison Mechanical Properties of Two Types of Light Weight Aggregate Concrete

This paper presents the behavior of concrete properties by replacing the conventional coarse aggregate used in the concrete mixture by two types of lightweight aggregate; Expanded Perlite Aggregate (EPA) and Volcanic Pumice (VP). To fulfill this aim; three laboratory tests were applied; density, compressive strength, and abrasion resistance, that conducted to extrapolate the range of the changes in the properties of concrete with existence those types of aggregate in the mixture. Also, the volumetric proportion adopted as a strategy for replacing the coarse aggregate by EPA or VP in the concrete mixture. Then, the volumetric proportion ranged from 10% to 50% with the variation step was 10%. Therefore, ten concrete mixtures are prepared and divided into two groups; each group contains five concrete mixes to represent the volumetric replacement (10-50)% of conventional coarse aggregate by EPA or VP. On the other hand, one extra mixture designed by using conventional aggregate (coarse and fine aggregate) without any inclusion of EPA or VP to be considered as a reference mixture. The obtained laboratory results of this study proved that the density, compressive strength, and abrasion resistance readings of concrete decreased at any volumetric proportion replacement of coarse aggregate by EPA or VP. The decrease in density and compressive strength of concrete readings amounted the peak level at 50% replacing of coarse aggregate by EPA, which were 38.19% and 77.37%, respectively than the reference mixture. Additionally, the compressive strength is an important factor affecting the abrasion resistance of concrete mixture, and loss of abrasion decreased as compressive strength increased

The brown seaweeds of Scotland, their importance and applications

More than 50% of the UK coastline is situated in Scotland under legislative jurisdiction; therefore, there is a great opportunity for regionally focused economic development by the rational use of sustainable marine bio-sources. We review the importance of seaweeds in general, and more specifically, wrack brown seaweeds which are washed from the sea and accumulated in the wrack zone and their economic impact. Rules and regulations governing the harvesting of seaweed, potential sites for harvesting, along with the status of industrial application are discussed. We describe extraction and separation methods of natural products from these seaweeds along with their phytochemical profiles. Many potential applications for these derivatives exist in agriculture, energy, nutrition, biomaterials, waste treatment (composting), pharmaceuticals, cosmetics and other applications. The chemical diversity of the natural compounds present in these seaweeds is an opportunity to further investigate a range of chemical scaffolds, evaluate their biological activities, and develop them for better pharmaceutical or biotechnological applications. The key message is the significant opportunity for the development of high value products from a seaweed processing industry in Scotland, based on a sustainable resource, and locally regulated

Lubrication at physiological pressures by polyzwitterionic brushes

The very low sliding friction at natural synovial joints, which have friction coefficients of mu < 0.002 at pressures up to 5 megapascals or more, has to date not been attained in any human-made joints or between model surfaces in aqueous environments. We found that surfaces in water bearing polyzwitterionic brushes that were polymerized directly from the surface can have m values as low as 0.0004 at pressures as high as 7.5 megapascals. This extreme lubrication is attributed primarily to the strong hydration of the phosphorylcholine-like monomers that make up the robustly attached brushes, and may have relevance to a wide range of human-made aqueous lubrication situations

Comparison Study of Axial Behavior of RPC-CFRP Short Columns

In this paper, the axial behaviors of reactive powder     concrete (RPC) short  columns confined with carbon fiber reinforced polymer (CFRP) were   investigated. All the specimens have square cross section of 100 mm × 100   mm and length of 400 mm with aspect ratio 4. The experimental work consists   of three groups. The first group consists of six specimens of RPC with 2% micro steel fiber, without ordinary reinforcing steel and confining by zero, one and two layer of CFRP respectively. The second group consists of six    specimens of RPC with 2% micro steel fiber and minimum ordinary reinforcing  steel and confining by zero, one and two layers of CFRP respectively. The third  group consists of four specimens of RPC without micro steel fiber and ordinary  reinforcing steel and confining by one and two layers of CFRP respectively.  Experimental data for strength, longitudinal and lateral displacement and  failure mode were obtained for each test. The toughness (area under the curve) for each test was obtained by using numerical integration. The RPC columns confined with CFRP showed stiffer behavior compared with RPC columns without CFRP. The ultimate load of the RPC columns with 2% micro steel  fiber + two layers of CFRP + minimum ordinary reinforcement were more than that of the RPC columns with 2% micro steel fiber + minimum ordinary   reinforcement and without CFRP by about 1.333.