155 research outputs found
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The current state of E-commerce in Jordan: Applicability and future prospects
This study aimed at determining the current state of e-commerce in Jordan, as well as its future prospects. The research population consisted of all Jordanian industrial, service and/or trade companies that have a registered website. The population size was 712 companies. A total of 118 questionnaires were distributed to randomly selected companies and 95 were returned. Cronbach alpha measure was used to test the reliability of the organizational questionnaire and was calculated to be 0.80 reflecting stability and
consistency of the scale and indicating the goodness of the measure. Other statistical tests
were used to test the research hypotheses such as One-Sample t-test, Independent-Samples t-test, One-Way ANOVA, Chi-Square and Bivariate Correlations (Pearson). The research indicated that Jordan has adequate and efficient e-commerce requirements in general, but there is no suitable and appropriate Community Culture in order to reach E-commerce Readiness Stage. Some recommendations are then made based on research findings
An interpretive approach to analysing the role and value of information systems in Jordanian financial organisations
Analysing investments in ISs in order to maximise benefits has become a prime concern, especially for private corporations. No formula of equilibrium exists that could link the injected amounts and accrued returns. The relationship is simply not straightforward. This thesis is based upon empirical work which involved sketching organisational ethnographies (four organographies and a sectography) into the role and value of information systems in Jordanian financial organisations. Besides deciphering the map of impacts, it explains the attributions of the variations in the impacts of ISs which were found to be related to the internal organisational processes: culturally and politically specific considerations, economically or technically rooted factors and environmental factors. The research serves as an empirical attempt to test out the applicability of adopting the interpretive paradigm to researching organisations in a developing country. The fieldwork comprised an exploratory stage, a detailed investigation of four case studies and a survey stage encompassing 16 organisations. Primary and secondary data were collected from multiple sources using a range of instruments. The evidence highlights the fact that little long term strategic planning was pursued; the emphasis was more focused on short term planning. There was no noticeable adoption of any strategic fit principle linking IS strategy to the corporate strategy. In addition, the benefits obtained were mostly intangible. Although ISs were central to the work of the organisations surveyed as the core technology, they were considered as tools or work enablers rather than weapons for competitive rivalry. The cultural specificity of IS impacts was evident and the cultural and political considerations were key factors in explaining the attributions of the variations in the impacts of ISs in JFOs. The thesis confirms that measuring the benefits of ISs is the problematic. However, in order to gain more insight, the phenomenon of "the use of ISs" has to be studied within its context
Non-vascularized fibular graft reconstruction after resection of giant aneurysmal bone cyst (ABC)
The aim of this study was to present the results of non-vascularized fibular graft for reconstruction of bone defects after en block resection of giant aneurysmal bone cyst (ABC) of the extremities. Between 1998 and 2006, three patients, aged 6, 8 and 23 years, with giant aneurysmal bone cysts were treated. The cysts were located in the humerus, proximal femur and metatarsal. All patients were given en bloc resection of the cyst followed by non-vascularized fibular bone graft, with the graft length ranging from 6 to 18 cm. All patients needed supplementary fixation with a single Kirschner wire or plate and screws. At the final follow-up, bony union was achieved in each case, and there was no recurrence, limitation of range of motion or disability. In addition, complete regeneration of the fibula at the donor site was seen in the two children. We propose a criterion for giant ABC, when the transverse diameter of the cyst is up to three times or more of the transverse diameter of the nearby bone, it is then called a giant ABC. Non-vascularized fibular graft is an optimal and valuable method for the reconstruction of bone defects after resection of giant ABC in the extremities
Modeling the Effects of Low Impact Development Practices on Streams at the Watershed Scale
Urban growth contributes to increasing storm water runoff which in turn causes an
increase in the frequency and severity of flooding. Moreover, increased storm water
runoff contributes to changing the character and volume of energy inputs to the stream.
Traditionally, storm water management controls such as detention pond had been
extensively studied and evaluated with respect to reducing and controlling peak flows.
Nonpoint source pollutants due to urbanization and expanding of agricultural fields have
become a big burden on municipalities and states.
Low Impact Development practices were developed to negate the negative impacts
of urbanization on water resources by reducing the runoff volume and peak flows as well
as improving outflow water quality. Though these practices have the capability of
reducing runoff volumes and enhancing outflow water quality, they can be costly.
Therefore, understanding the impact of installing LID practices on a watershed scale is
becoming increasingly important.
In this study, field experiment and model study were applied to evaluate the
effectiveness of LID practices on a watershed scale in the Blunn Creek Watershed
located in Austin, Texas. The three LID practices which were evaluated in this study are
permeable pavements, a bioretention area, and a detention pond. The main objective of
this study was to investigate the influences of these practices at a watershed scale on:
potential reduction on channel bank erosion, potential reduction on flood, and potential
impact on aquatic life.
This study was one of very few studies that take place in the Blackland clay soil in Texas. A combination of different levels of LID practices such as permeable pavement and bioretention area resulted with achieving the main goal of this study of reducing stream bank erosion, bankfull exceedance, and maintaining acceptable flows for the integrity of aquatic life habitat. All LID practices have shown significant difference with respect to a control treatment at 95% confidence ratio. Performance of the modeled LID practices was validated by showing acceptable agreement in the percentage of reductions in total runoff between field experiments and model data
Controlling secondary flows in Taylor-Couette flow using spanwise superhydrophobic surfaces
Turbulent shear flows are abundant in geophysical and astrophysical systems
and in engineering-technology applications. They are often riddled with
large-scale secondary flows that drastically modify the characteristics of the
primary stream, preventing or enhancing mixing, mass, and heat transfer. Using
experiments and numerical simulations, we study the possibility of modifying
these secondary flows by using superhydrophobic surface treatments that reduce
the local shear. We focus on the canonical problem of Taylor-Couette flow, the
flow between two coaxial and independently-rotating cylinders, which has robust
secondary structures called Taylor rolls that persist even at significant
levels of turbulence. We generate these structures by rotating only the inner
cylinder of the system, and show that a spanwise superhydrophobic treatment can
weaken the rolls through a mismatching surface heterogeneity, as long as the
roll size can be fixed. The minimum hydrophobicity of the treatment required
for this flow control is rationalized, and its effectiveness beyond the
Reynolds numbers studied here is also discussed
Comparison of Effectiveness of Germania Honey Compared to Manuka Honey in Methicillin-Resistant Staphylococcus aureus (MRSA) Killing
Purpose:
Manuka honey is currently used in medical-grade sterile wound treatment products and has been shown to be effective in methicillin-resistant Staphylococcus aureus (MRSA) killing in vitro and in wound healing in a number of case studies and series. Locally produced honey in Pakistan and Chile have been proposed to be as effective as Manuka honey in bacterial killing in vitro, presenting potentially more accessible and affordable alternatives. In this study, we compared the effectiveness of a local Germania honey from Saudi Arabia to Manuka honey MGO 550 for in vitro killing of MRSA.
Methodology:
Overnight Muller Hinton broth cultures of 50 wound culture isolates of MRSA from 50 patients were incubated with a series of dilutions of Manuka honey MGO 550 and corresponding Germania honey dilutions for 24 h. Turbidity was assessed to determine whether bacterial growth had occurred, and no growth was confirmed by a further 24 h sub-culture on blood agar.
Results/Key findings:
Manuka honey MGO 550 was significantly more effective than Germania honey at MRSA killing at 100% v/v, 50% v/v and 25% v/v (p=0.025, 0.000265, and 0.000112 respectively)
Conclusion:
Manuka honey MGO 550 is significantly more effective in killing MRSA in vitro than Germania honey. Germania honey does not appear to be a promising locally produced alternative to Manuka honey for the development of honey-based wound dressings. Further experiments could determine if Germania honey is effective against other bacterial species
Investigating Rainwater Harvesting as a Stormwater Best Management Practice and as a Function of Irrigation Water Use
Stormwater runoff has negative impacts on water resources, human health and environment. In this research the effectiveness of Rain Water Harvesting (RWH) systems is examined as a stormwater Best Management Practice (BMP). Time-based, evapotranspiration-based, and soil moisture-based irrigation scheduling methods in conjunction with RWH and a control site without RWH were simulated to determine the effect of RWH as a BMP on a single-family residence scale. The effects of each irrigation scheduling method on minimizing water runoff leaving the plots and potable water input for irrigation were compared. The scenario that reflects urban development was simulated and compared to other RWH-irrigation scheduling systems by a control treatment without a RWH component. Four soil types (sand, sandy loam, loamy sand, silty clay) and four cistern sizes (208L, 416L, 624L, 833L) were evaluated in the urban development scenario.
To achieve the purpose of this study; a model was developed to simulate daily water balance for the three treatments. Irrigation volumes and water runoff were compared for four soil types and four cistern sizes. Comparisons between total volumes of water runoff were estimated by utilizing different soil types, while comparisons between total potable water used for irrigation were estimated by utilizing different irrigation scheduling methods.
This research showed that both Curve Number method and Mass-Balance method resulted in the greatest volumes of water runoff predicted for Silty Clay soil and the least volumes of water runoff predicted for Sand soil. Moreover, increasing cistern sizes resulted in reducing total water runoff and potable water used for irrigation, although not at a statistically significant level. Control treatment that does not utilize a cistern had the greatest volumes of predicted supplemental water among all soil types utilized, while Soil Moisture-based treatment on average had the least volume of predicted supplemental water
Transient MHD Double-Diffusive Natural Convection over a Vertical Surface Embedded in a Non-Darcy Porous Medium
The problem of transient, laminar, MHD double-diffusive free convection over a permeable vertical plate embedded in Darcy and non-Darcy porous medium is numerically investigated. Nonsimilarity solutions are obtained for constant wall temperature and concentration with a specified power law of mass flux parameter. The effects of the magnetic parameter, the inertial coefficient, Lewis number, the buoyancy ratio, and the lateral mass flux on heat and mass transfer coefficients are presented and discussed
Interrogating the effect of an orifice on the upward two-phase gas–liquid flow behavior
Experiments are reported on an air–water mixture flowing through an orifice in a vertical pipe. Time series of cross-sectionally averaged void fractions have been measured at nine axial positions by using a conductance probe technique. A series of six orifices with different thicknesses and apertures were employed. The Probability Density Function, the Power Spectral Density of the time series of cross sectionally averaged void fractions and the cross-correlation of time series from adjacent probes have been obtained to determine the effect of the orifice on the flow characteristics. The diameter area ratio and the thickness of the orifice have a higher influence on bubbly than on slug and churn flows. The recovery length is about 20, 10 and 7 pipe diameter downstream the orifice for these three flow patterns respectively. Homogenization effect needs a minimum liquid superficial velocity. Its position occurs depends on the value of this velocity and on the orifice fractional open area.
Just downstream the orifice, the structure velocity increases for the bubbly and slug flows and decreases for churn flow. For bubble and slug flows, there is persistency of the frequency when passing through the orifice from the upstream to the downstream pipe
New perspectives on interdisciplinary earth science at the Dead Sea: The DESERVE project
The Dead Sea region has faced substantial environmental challenges in recent decades, including water resource scarcity, ~ 1 m annual decreases in the water level, sinkhole development, ascending-brine freshwater pollution, and seismic disturbance risks. Natural processes are significantly affected by human interference as well as by climate change and tectonic developments over the long term. To get a deep understanding of processes and their interactions, innovative scientific approaches that integrate disciplinary research and education are required. The research project DESERVE (Helmholtz Virtual Institute Dead Sea Research Venue) addresses these challenges in an interdisciplinary approach that includes geophysics, hydrology, and meteorology. The project is implemented by a consortium of scientific institutions in neighboring countries of the Dead Sea (Israel, Jordan, Palestine Territories) and participating German Helmholtz Centres (KIT, GFZ, UFZ). A new monitoring network of meteorological, hydrological, and seismic/geodynamic stations has been established, and extensive field research and numerical simulations have been undertaken. For the first time, innovative measurement and modeling techniques have been applied to the extreme conditions of the Dead Sea and its surroundings. The preliminary results show the potential of these methods. First time ever performed eddy covariance measurements give insight into the governing factors of Dead Sea evaporation. High-resolution bathymetric investigations reveal a strong correlation between submarine springs and neo-tectonic patterns. Based on detailed studies of stratigraphy and borehole information, the extension of the subsurface drainage basin of the Dead Sea is now reliably estimated. Originality has been achieved in monitoring flash floods in an arid basin at its outlet and simultaneously in tributaries, supplemented by spatio-temporal rainfall data. Low-altitude, high resolution photogrammetry, allied to satellite image analysis and to geophysical surveys (e.g. shear-wave reflections) has enabled a more detailed characterization of sinkhole morphology and temporal development and the possible subsurface controls thereon. All the above listed efforts and scientific results take place with the interdisciplinary education of young scientists. They are invited to attend joint thematic workshops and winter schools as well as to participate in field experiments
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