884 research outputs found

    Grounded theory and action research as pillars for interpretive information systems research: A comparative study

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    AbstractIn the literature survey, there is evidence “why an interpretive paradigm is more suitable for evaluating e-government systems”. However, more than one method can be used when applying interpretive paradigm for evaluating information systems (as we do not consider e-government systems as exception) such as Action Research (AR) and Grounded Theory (GT). In this regard, two problems will arise: First, there is no explicit method that clarifies how AR and GT methods can be used for evaluating information systems. The second problem is to determine which method of them will be more appropriate for evaluating information systems.Accordingly, two frameworks for evaluating e-government systems have been proposed, namely ‘Grounded Evaluation Framework’ (GEF) and ‘Action Research Evaluation Framework’ (AREF), which are based on Grounded Theory (GT) and Action Research (AR) methods respectively, to give an example how GT and AR methods can be used in evaluating information systems. The suggested GEF and AREF have been applied to the “University Enrolment Service” in Egyptian e-government, and the findings have been analyzed to conclude that GEF is more appropriate for evaluating e-government systems

    Source characteristics of a moderate earthquake (M 4.9)using empirical Green ’s function technique

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    The rupture process of a moderate earthquake (M 4.9)on 28th January 1999 was analyzed using velocity records at local distances less than 80 km.The characterization of the rupture process was obtained from studying aftershocks distribution,azimuthal variations of Relative Source Time Functions (RSTFs),and a set of spatio-temporal slip models.RSTFs were retrieved by deconvolution of small aftershock records from those of the mainshock.In addition,velocity P -wave records of the respective event were inverted to recover slip distribution on the fault plane using the records of aftershocks as Empirical Green Functions (EGFs).The waveform inversion was adopted using three EGFs.In the inversion,the rupture propagation velocity was fixed and assumed to be eight-tenths of the local shear wave velocity.The total seismic moment was estimated to range from 0.011 E +18 Nm (Mw =4.6) to 0.017 E +18 Nm (Mw =4.8).The hypocentral distribution of the aftershocks,azimuthal variations of RSTFs, and the set of slip distribution models were exhibited bilateral rupture propagation along the strike and dip of the fault plane.The presence of two to three high slip patches on the fault plane suggested that a complex rupture pattern is detectable for a moderate size earthquake.However,the so-called nucleation phase was invisible in the present analysis

    Synthesis and efficiency of new pyridine, chromene and thiazole containing compounds as antimicrobial and antioxidant agents

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    ABSTRACT. The versatile scaffold, N'-(2-cyanoacetyl)-2-hydroxybenzohydrazide (3) was utilized in the production of new pyridine, chromene and thiazole derivatives as antimicrobial and antioxidant agents. The synthetic strategy involves the treatment of precursor 3 with various arylidene-malononitrile and 3-aryl-2-cyanoacrylate compounds to furnish substituted pyridines 5 and 7. The interaction of 3 with salicylaldehyde and/or phenyl isothiocyanate followed by cyclization with chloroacetone produced the corresponding 2-imino-2H-chromene-3-carbohydrazide and (thiazol-2-ylidene-acetyl)-salicylic acid hydrazide compounds 8 and 9, respectively. The structural features of the synthesized compounds were confirmed by using spectroscopic methods such as (IR, 1H NMR, 13C NMR and MS). The new pyridine, chromene and thiazole products showed potent antioxidants and antimicrobial activities. The thiazole derivative 9 exhibited the highest anti-bacterial and antifungal activities against S. aureus (75.0%) and B. subtilis (73.9%) and C. albicans (66.6%). The combination between salicylic acid hydrazide and thiazole moieties in the hybrid 9 indicated the best antioxidant activity (87.9%).                 KEY WORDS: Salicylic hydrazide, Arylidene-malononitrile, Pyridine, Thiazole, Antioxidant   Bull. Chem. Soc. Ethiop. 2022, 36(1), 137-148.                                                            DOI: https://dx.doi.org/10.4314/bcse.v36i1.12                                                      &nbsp

    INTELLIGENT CONTROLLER FOR TRACKING A 14-INCH CELESTRON TELESCOPE

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    The paper proposes a design of two fuzzy and Proportional-Integral-Derivative (PID) controllers for a position tracking of the 1400 Celestron telescope. The position responses; right ascension and declination in such a way that it minimizes the integral absolute error (ITAE) using a modified particle swarm optimization (MPSO). Based on the structure of the MPSO, the accelerated coefficients of the particle swarm optimization are adapted dynamically by minimizing the system error with the iteration index. The adaptive control tool combines the Fuzzy controller and MPSO to produce a powerful controller in the system (FLC-PSO). The parameters of membership functions and the PID gains are tuned simultaneously based on the MPSO, which is an efficient and simple tool for the multidimensional problem. The simulation results for both controllers are analyzed and compared on a basis of the time response specifications

    A Strategic Roadmap for Maximizing Big Data Return

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    Big Data has turned out to be one of the popular expressions in IT the last couple of years. In the current digital period, according to the huge improvement occurring in the web and online world innovations, we are facing a gigantic volume of information. The size of data has expanded significantly with the appearance of today's innovation in numerous segments, for example, assembling, business, and science. Types of information have been changed from structured data-driven databases to data including documents, images, audio, video, and social media contents referred to as unstructured data or Big Data. Consequently, most of the organizations try to invest in the big data technology aiming to get value from their investment. However, the organizations face a challenge to determine their requirements and then the technology that suits their businesses. Different technologies are provided by variety of vendors, each of them can be used, and there is no methodology helping them for choosing and making a right decision. Therefore, the objective of this paper is to construct a roadmap for helping the organizations determine their needs and selecting a suitable technology and applying this conducted proposed roadmap practically on two companies

    Nonuniformity in Lattice Contraction of Bismuth Nanoclusters Heated Near Its Melting Point

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    The structural properties of bismuth nanoclusters were investigated with transmission high-energy electron diffraction from room temperature up to 525 ± 6 K. The Bi nanoclusters were fabricated by thermal evaporation at room temperature on transmission electron microscope grids coated with an ultrathin carbon film, followed by thermal and femtosecond laser annealing. The annealed sample had an average cluster size of ∼14 nm along the minor axis and ∼16 nm along the major axis. The Debye temperature of the annealed nanoclusters was found to be 53 ± 6 K along the [012] direction and 86 ± 9 K along the [110] direction. At T = 464 ± 6 K, the diffraction intensity started to deviate from Debye-Waller behavior due to increased lattice anharmonicity. The onset of the melting of the Bi nanoclusters was T ∼ 500 ± 6 K, as measured by the reduction of the nanocluster size through the formation of a liquid shell detected by the width of the diffraction rings. The thermal expansion coefficient of the Bi (012) and (110) planes is positive up to ∼ 499 11 K. However, the expansion coefficient of the Bi (012) planes showed a transition from a positive to a negative value that occurs over the temperature range Tc ∼ 499 ± 11 K to 511 ± 8 K. For the Bi (110) planes, the thermal expansion coefficient is positive up to their melting point, which is 525 ± 6 K. © 2011 American Institute of Physics. [doi:10.1063/1.3565028

    EFFECT OF GRINDING AND PARTICLE SIZE ON SOME PHYSICAL AND RHEOLOGICAL PROPERTIES OF CHITOSAN

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    The present study was conducted to prepare nano-chitosan particles (CN) by ultrafine grinding  from crude chitosan powder (CC) using a ball mill with 130 numbers of zirconia beads in range from 0.5 to 1.5 mm diameter (75 beads 0.5 mm diameter, 30 beads 1.0 mm diameter and 25 beads 1.5 mm diameter). In addition, physical and rheological properties of chitosan solutions were determined. The results revealed that ultrafine grinding has effectively milled the chitosan particles to nanoscale. Prepared chitosan nanoparticles were characterized by  devices  X-Ray Diffraction (XRD), Zetasizer particle sizes and Zeta potential of chitosan particles (after milling for 30, 60 and 90 minutes). The particle size of nano-chitosan was distributed in a range of 250-600 nm. with a polydispersity index use as an anti-oxidant and antimicrobial with reducing the amount used to deliver the desired purpose. Additional research is required to further investigate the potential value-added utilization of these chitosan derivatives in improving the quality and safety of some food products

    NAKED EYE ESTIMATES OF MORNING PRAYER AT TUBRUQ OF LIBYA

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    Naked eye observations at Tubruq sky (φ = 32° 05´, λ = 23° 59´) in Libya at the Mediterranean coast (see-desert background) during the two years (2008 – 2009) of morning twilight have been recorded.  These observations led us to get some estimates about morning twilight, as it is necessary to determine the time of the True Dawn (Al-Fajr Prayer Time).  this research aims to determine the correct time of Al-Fajr Prayer by finding the accurate angle of the sun vertical depression below the horizon that is associated with legitimate mark. The Methode used in this research was field research while the observations have been recorded by monitoring the first white thread on the eastern horizon (True Dawn) that announces the time of the Morning Prayer (Al-Fajr Prayer).  The azimuthally range of observation about the solar vertical extends from 0° up to ±20°, while the phenomenon was followed from 0° up to 20° along the altitudinal range.  This research gives a result that a beginning of the morning twilight is estimated to be around 13.5° depression of the sun below the horizon.  This value can reach a minimum depression around 11.5° at low visibility and a maximum around 13.5° at a very god visibility

    Coherent Phonons in Bismuth Film Observed by Ultrafast Electron Diffraction

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    The generation of coherent phonons in polycrystalline bismuth film excited with femtosecond laser pulse is observed by ultrafast time-resolved electron diffraction. The dynamics of the diffracted intensities from the (110), (202), and (024) lattice planes show pronounced oscillations at 130-150 GHz. The origin of these coherent acoustic phonons is discussed in view of optical phonon decay into two acoustic phonons. Different drop times in the intensity of the diffraction orders are observed and interpreted as anisotropy in the energy transfer rate of coherent optical phonons
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