Introduces an integrated approach for information system evaluation. The approach utilizes a model which consists of four parts: system environment; methodologies; documentation;…
Abstract
Introduces an integrated approach for information system evaluation. The approach utilizes a model which consists of four parts: system environment; methodologies; documentation; and performance indices. The model was implemented in a selected sample of organizations in Kuwait. Presents an in‐depth, data‐based profile of the organizations studied. A classification of the organizations according to the evaluation results indicated that 48.6 per cent are above average rating. The model used could be modified to cater for any information system environment.
Details
Keywords
Proposes a quality assurance model for the development of a computer‐based information system covering the different system life cycle stages. A field investigation for the…
Abstract
Proposes a quality assurance model for the development of a computer‐based information system covering the different system life cycle stages. A field investigation for the information systems in a selected number of organizations in Kuwait revealed that a limited number of organizations have a quality assurance department, and limited evaluation procedures were implemented. Emphasizes the need for applying the concept of quality assurance to obtain a high quality of software product.
Details
Keywords
Constructs a knowledge‐based simulation model for job shopscheduling simulation techniques to build the initial status of theknowledge base. Uses the simulation experiments to…
Abstract
Constructs a knowledge‐based simulation model for job shop scheduling simulation techniques to build the initial status of the knowledge base. Uses the simulation experiments to study the effect of technological factors, such as machine loading conditions and criteria of scheduling performance requirements, on the selection of scheduling priority rules. Implements the model with real workshop data to test its validity to cater for real‐world situations such as machine group centres, more than one machine and the availability of operators. The proposed model yields satisfactory results.
Details
Keywords
Turgul Oktay, Mehmet Konar, Murat Onay, Murat Aydin and Mohamed Abdallah Mohamed
The purpose of this paper is to increase flight performance of small unmanned aerial vehicle (UAV) using simultaneous UAV and autopilot system design.
Abstract
Purpose
The purpose of this paper is to increase flight performance of small unmanned aerial vehicle (UAV) using simultaneous UAV and autopilot system design.
Design/methodology/approach
A small UAV is manufactured in Erciyes University, College of Aviation, Model Aircraft Laboratory. Its wing and tail is able to move forward and backward in the nose-to-tail direction in prescribed interval. Autopilot parameters and assembly position of wing and tail to fuselage are simultaneously designed to maximize flight performance using a stochastic optimization method. Results are obtained are used for simulations.
Findings
Using simultaneous UAV and autopilot system design idea, flight performance is maximized.
Research limitations/implications
Permission of Directorate General of Civil Aviation in Turkey is required for testing UAVs in long range.
Practical implications
Simultaneous design idea is very beneficial for improving UAV flight performance.
Originality/value
Creating a novel method to improve flight performance of UAV and developing an algorithm performing simultaneous design idea.
Details
Keywords
Mohamed Ali Zdiri, Badii Bouzidi and Hsan Hadj Abdallah
This paper aims to analyze and investigate the performance of an improved fault detection and identification (FDI) method based on multiple criteria, applied to six-switch…
Abstract
Purpose
This paper aims to analyze and investigate the performance of an improved fault detection and identification (FDI) method based on multiple criteria, applied to six-switch three-phase inverter (SSTPI)-fed induction motor (IM) drives under both single and multiple open insulated-gate bipolar transistors(IGBT) faults.
Design/methodology/approach
This paper proposes an advanced diagnostic method for both single and multiple open IGBT faults dedicated to SSTPI-fed IM drives considering five distinct faulty operating conditions as follows: a single IGBT open-circuit fault, a single-phase open-circuit fault, a non-crossed double fault in two different legs, a crossed double fault in two different legs and a three-IGBT open-circuit fault. This is achieved because of the introduction of a new diagnosis variable provided using the information of the slope of the current vector in (α-β) frame. The proposed FDI method is based on the synthesis and the analysis, under both healthy and faulty operations, of the behaviors of the introduced diagnosis variable, the three motor phase currents and their normalized average values. Doing so, the developed FDI method allows a best compromise of fast detection and precision localization of IGBT open-circuit fault of the inverter.
Findings
Simulation works, carried out considering the implementation of the direct rotor flux oriented control in an IM fed by the conventional SSTPI, have proved the high performance of the advanced FDI method in terms of fast fault detection associated with a high robustness against false alarms, against speed and load torque fast variations and against the oscillations of the DC-bus voltage in the case of both healthy and faulty operations.
Research limitations/implications
This work should be extended considering the validation of the obtained simulation results through experiments.
Originality/value
Different from other FDI methods, which suffer from a low diagnostic effectiveness for low load levels and false alarms during transient operation, this method offers the potentialities to overcome these drawbacks because of the introduction of the new diagnosis variable. This latter, combined with the information provided from the three motor phase currents and their normalized average values allow a more efficient detection and identification of IGBT open-circuit fault.
Details
Keywords
Bassam Abdallah, Mahmoud Kakhia and Walaa Zetoune
This study aims to carry out the deposition of zinc sulfide (ZnS) thick films on glass and silicon (100) substrates using radio frequency (RF) magnetron sputtering method at…
Abstract
Purpose
This study aims to carry out the deposition of zinc sulfide (ZnS) thick films on glass and silicon (100) substrates using radio frequency (RF) magnetron sputtering method at different powers. Film structure has been analyzed by X-ray diffraction (XRD); the patterns showed that the films possesses a cubic structure with (111) preferred orientation. Photoluminance (PL) intensity of the films has been related to the crystallinity, which is varied with the power.
Design/methodology/approach
Scanning electron microscope (SEM) images have been used to discover the films’ morphology. The stoichiometry has been confirmed by energy dispersive X-ray spectroscopy (EDX) analysis. MicroRaman spectroscopy has been used to validate the film structure. Gas-sensing studies were carried out by means of a static gas chamber to sense acetone, ethanol, methanol, H2O and NH3 vapor in air ambient.
Findings
ZnS has a stoichiometric and cubic structure. The band gaps and photoluminance intensity of the films are correlated with the crystallinity, which is varied with the power. The EDX analysis approved the stoichiometry of the prepared films. Acetone, ethanol, humidity (H2O), methanol and NH3 vapor gases were used to justify the sensing properties at 25°C of the thickest ZnS film.
Originality/value
High-quality ZnS films have been obtained at different powers without annealing. Gases sensing properties at 25°C are justified for deposited ZnS films using acetone, ethanol, humidity (H2O), methanol and NH3 vapor gases. It reveals good response for NH3 and humidity vapors at room temperature; the sensing functioning at this temperature was attractive in recent research.
Details
Keywords
Adel Abdallah, Mohamed M. Fouad and Hesham N. Ahmed
The purpose of this paper is to introduce a novel intensity-modulated fiber optic sensor for real-time intrusion detection using a fiber-optic microbend sensor and an optical…
Abstract
Purpose
The purpose of this paper is to introduce a novel intensity-modulated fiber optic sensor for real-time intrusion detection using a fiber-optic microbend sensor and an optical time-domain reflectometer (OTDR).
Design/methodology/approach
The proposed system is tested using different scenarios using person/car as intruders. Experiments are conducted in the lab and in the field. In the beginning, the OTDR trace is obtained and recorded as a reference signal without intrusion events. The second step is to capture the OTDR trace with intrusion events in one or multiple sectors. This measured signal is then compared to the reference signal and processed by matrix laboratory to determine the intruded sector. Information of the intrusion is displayed on an interactive screen implemented by Visual basic. The deformer is designed and implemented using SOLIDWORKS three-dimensional computer aided design Software.
Findings
The system is tested for intrusions by performing two experiments. The first experiment is performed for both persons (>50 kg) in the lab and cars in an open field with a car moving at 60 km/h using two optical fiber sectors of lengths 200 and 500 m. For test purposes, the deformer length used in the experiment is 2 m. The used signal processing technique in the first experiment has some limitations and its accuracy is 70% after measuring and recording 100 observations. To overcome these limitations, a second experiment with another technique of signal processing is performed.
Research limitations/implications
The system can perfectly display consecutive intrusions of the sectors, but in case of simultaneous intrusions of different sectors, which is difficult to take place in real situations, there will be the ambiguity of the number of intruders and the intruded sector. This will be addressed in future work. Suitable and stable laser power is required to get a suitable level of backscattered power. Optimization of the deformer is required to enhance the sensitivity and reliability of the sensor.
Practical implications
The proposed work enables us to benefit from the ease of implementation and the reduced cost of the intensity-modulated fiber optic sensors because it overcomes the constraints that prevent using the intensity-modulated fiber optic sensors for intrusion detection.
Originality/value
The proposed system is the first time long-range intensity-modulated fiber optic sensor for intrusion detection.
Details
Keywords
Abou-Elhagag A. Hermas, Abobakr Mohamed Elnady and Reham M. Ali
Although stainless steel (SS) has good corrosion resistance in most aqueous solutions, it suffers corrosion in some solutions which contain aggressive ions such as sulfide ions…
Abstract
Purpose
Although stainless steel (SS) has good corrosion resistance in most aqueous solutions, it suffers corrosion in some solutions which contain aggressive ions such as sulfide ions. This study aims to use some cephalosporins (cefotaxime, cephapirin and cefazolin) as corrosion inhibitors of commercial SS in 0.5 M H2SO4 solution containing sulfide ions at 30°C.
Design/methodology/approach
The study was carried out using weight loss method, potential-time, linear polarization, potentiodynamic polarization, electrochemical impedance measurements, scanning electron microscopy, Fourier transform infrared and energy dispersive X-ray analysis.
Findings
The presence of the cephalosporin compound in the corrosive medium shifted the corrosion potential of SS to much positive side, which enhances self-passivation of SS, and the shifting increased with increasing inhibitor concentration. The cephalosporin compounds worked as effective inhibitors with mainly anodic and the efficiency increase as cefotaxime < cephapirin < cefazolin. The inhibitors form a protective adsorbed layer, which enriches the surface content of Ni and Cr and thus assists the SS to be passive.
Originality/value
The antibiotics cephalosporins could be used as effective corrosion inhibitors for SS in acidic solutions containing sulfide ions. The inhibitors enhances the the passive oxide film of SS even in presence of aggressive ions such as sulfide ions.
Details
Keywords
Hala M.G. Amin, Rasha S. Hassan, Hebatallah Ghoneim and Amr S. Abdallah
This study aims to identify and discuss influential aspects of accounting education literature in the digital era, such as key streams, themes, authors, keywords, journals…
Abstract
Purpose
This study aims to identify and discuss influential aspects of accounting education literature in the digital era, such as key streams, themes, authors, keywords, journals, affiliations and countries. It also constructs agendas for future research.
Design/methodology/approach
The current study uses a bibliometric approach to analyze 287 studies indexed by the Scopus Database from 1982 to 2023.
Findings
The analysis reveals three themes: “the impact of emerging technologies on the accounting profession,” “the essential skills for modern accountants” and “the integration of technology into the accounting curricula.” Beyond this, the analysis points out that Macquarie University and the Queensland University of Technology were the most productive institutions. Furthermore, the leading journal was the Accounting Education Journal. The USA and Australia were leading in total citations and publications, while 2023 was the peak publishing year.
Research limitations/implications
The study acknowledges that alternative search keywords, databases and research categories may reveal unexplored relationships. The present study’s findings have crucial theoretical and practical implications for researchers in the accounting domain, higher education institutions and policymakers.
Originality/value
The study contributes to the extant accounting literature by presenting a holistic view of the impact of emerging technologies on accountants’ skills, profession and accounting curriculum, identifying gaps in the literature and proposing a research agenda.
Details
Keywords
Ahmed Ayadi, Haythem Nasraoui, Zied Driss, Abdallah Bouabidi and Mohamed Salah Abid
The purpose of this paper is to study a solar thermal system. Solar chimney power plants (SCPPs) produce electrical energy and thermal heat from solar radiation. The thermal study…
Abstract
Purpose
The purpose of this paper is to study a solar thermal system. Solar chimney power plants (SCPPs) produce electrical energy and thermal heat from solar radiation. The thermal study of SCPPs is required, as these solar systems are characterized by high costs.
Design/methodology/approach
This study presents a numerical study of unsteady airflow characteristics inside an SCPP. In fact, the generated power of the SCPP depends on environmental conditions. To validate this study, a solar prototype is built in the National School of Engineers of Sfax, University of Sfax, Tunisia, North Africa. The system is mainly composed by a collector, an absorber, a chimney and a turbine. The collector diameter is 2750 mm, the collector roof height is 50 mm, the chimney height is 3,000 mm and the turbine diameter is 150 mm.
Findings
The local characteristics of the air flow are presented and analyzed, such as the distribution of the temperature, the magnitude velocity and the total pressure. Analysis confirms that ambient air temperature and solar radiation are important environmental variables for the improvement of solar chimney efficiency.
Originality/value
Although much work has been done to date, it has been noted that the most published works have presented the profiles of air velocity and air temperature in a specific position within the solar setup. However, these profiles could sometimes be misinterpreted. In fact, some researchers did not focus on the distribution of air temperature, air velocity and pressure. These parameters are important to optimize the solar system. Indeed, the most published works deal with a larger prototype, such as the Manzanares prototype. However, it has not found connections between larger and small prototypes of SCPP.